重构代码

adapters/cc_anthropic_adapter.py

@@ -18,13 +18,21 @@ from __future__ import annotations
 import json
 from typing import Any
 
+from adapters.helpers import (
+    build_cc_message,
+    build_cc_response,
+    build_cc_tool_call,
+    build_cc_usage,
+    extract_text,
+    make_cc_chunk,
+    parse_json_safe,
+    stringify_content,
+)
 from utils.http import gen_id
 from utils.tool_fixer import fix_anthropic_tool_use, normalize_args, repair_str_replace_args
 
 JsonDict = dict[str, Any]
 
-
-# Anthropic stop_reason → OpenAI finish_reason
 _STOP_REASON_MAP = {
     'end_turn': 'stop',
     'max_tokens': 'length',
@@ -78,23 +86,18 @@ def messages_to_cc_response(data: JsonDict, request_id: str | None = None) -> Js
     data = fix_anthropic_tool_use(data)
 
     content_text, reasoning_text, tool_calls = _collect_response_parts(data.get('content', []))
-    message = _build_cc_message(content_text, reasoning_text, tool_calls)
     usage = data.get('usage', {})
 
-    return {
+    return build_cc_response(
-        'id': request_id,
+        response_id=request_id,
-        'object': 'chat.completion',
+        message=build_cc_message(content_text, reasoning_text, tool_calls),
-        'model': data.get('model', 'claude'),
+        finish_reason=_STOP_REASON_MAP.get(data.get('stop_reason', 'end_turn'), 'stop'),
-        'choices': [{
+        usage=build_cc_usage(
-            'index': 0,
-            'message': message,
-            'finish_reason': _STOP_REASON_MAP.get(data.get('stop_reason', 'end_turn'), 'stop'),
-        }],
-        'usage': _build_cc_usage(
             input_tokens=usage.get('input_tokens', 0),
             output_tokens=usage.get('output_tokens', 0),
         ),
-    }
+        model=data.get('model', 'claude'),
+    )
 
 
 # ═══════════════════════════════════════════════════════════
@@ -124,12 +127,8 @@ class AnthropicStreamConverter:
         self._input_tokens = 0
         self._output_tokens = 0
 
-    def process_event(self, event_type: str, event_data: JsonDict) -> list[str]:
+    def process_event(self, event_type: str, event_data: JsonDict) -> list[JsonDict]:
-        """处理单个 Anthropic SSE 事件。
+        """处理单个 Anthropic SSE 事件，返回 CC chunk dict 列表。"""
-
-        调用方会按事件顺序不断喂入 event/data，这里根据事件类型拆成一个或多个 CC chunk
-        字符串，交给上层直接作为 SSE data 发送给 Cursor。
-        """
         if event_type == 'message_start':
             return self._handle_message_start(event_data)
         if event_type == 'content_block_start':
@@ -140,104 +139,64 @@ class AnthropicStreamConverter:
             return self._handle_message_delta(event_data)
         return []
 
-    def _handle_message_start(self, event_data: JsonDict) -> list[str]:
+    def _handle_message_start(self, event_data: JsonDict) -> list[JsonDict]:
-        """处理消息开始事件，产出 assistant 角色起始 chunk。
-
-        这个起始 chunk 很重要，因为 Cursor 侧通常会依赖首个带 role 的 chunk 来初始化
-        当前 assistant 消息。
-        """
         message = event_data.get('message', {})
         self._input_tokens = message.get('usage', {}).get('input_tokens', 0)
-
         chunk = self._make_chunk(delta={'role': 'assistant', 'content': ''})
         if message.get('model'):
             chunk['model'] = message['model']
-        return [self._dump_chunk(chunk)]
+        return [chunk]
 
-    def _handle_content_block_start(self, event_data: JsonDict) -> list[str]:
+    def _handle_content_block_start(self, event_data: JsonDict) -> list[JsonDict]:
-        """处理内容块开始事件。
-
-        目前这里只需要显式处理 `tool_use`，因为文本和 thinking 的真正内容都在后续 delta
-        事件里；而 tool_use 需要先开一个空 arguments 的 tool_call 槽位。
-        """
         block = event_data.get('content_block', {})
         if block.get('type') != 'tool_use':
             return []
-
         self._tool_index += 1
-        return [self._dump_chunk(self._make_chunk(delta={
+        return [self._make_chunk(delta={
             'tool_calls': [{
                 'index': self._tool_index,
                 'id': block.get('id', gen_id('toolu_')),
                 'type': 'function',
-                'function': {
+                'function': {'name': block.get('name', ''), 'arguments': ''},
-                    'name': block.get('name', ''),
-                    'arguments': '',
-                },
             }]
-        }))]
+        })]
 
-    def _handle_content_block_delta(self, event_data: JsonDict) -> list[str]:
+    def _handle_content_block_delta(self, event_data: JsonDict) -> list[JsonDict]:
-        """处理内容块增量事件。
-
-        Anthropic 会把文本、思考内容、工具参数拆成不同 delta 类型，这里要分别映射成
-        OpenAI chunk 里的 `content`、`reasoning_content` 和 `tool_calls.function.arguments`。
-        """
         delta = event_data.get('delta', {})
         delta_type = delta.get('type', '')
 
         if delta_type == 'text_delta' and delta.get('text'):
-            return [self._dump_chunk(self._make_chunk(delta={'content': delta['text']}))]
+            return [self._make_chunk(delta={'content': delta['text']})]
-
         if delta_type == 'thinking_delta' and delta.get('thinking'):
-            return [self._dump_chunk(self._make_chunk(delta={'reasoning_content': delta['thinking']}))]
+            return [self._make_chunk(delta={'reasoning_content': delta['thinking']})]
-
         if delta_type == 'input_json_delta' and delta.get('partial_json'):
-            return [self._dump_chunk(self._make_chunk(delta={
+            return [self._make_chunk(delta={
                 'tool_calls': [{
                     'index': self._tool_index,
                     'function': {'arguments': delta['partial_json']},
                 }]
-            }))]
+            })]
-
         return []
 
-    def _handle_message_delta(self, event_data: JsonDict) -> list[str]:
+    def _handle_message_delta(self, event_data: JsonDict) -> list[JsonDict]:
-        """处理消息收尾事件，补出 finish_reason 和 usage。
-
-        当 Anthropic 发出 `message_delta` 时，说明这一轮 assistant 输出已经收束，
-        这里会统一生成最后一个带 usage 的收尾 chunk。
-        """
         delta = event_data.get('delta', {})
         usage = event_data.get('usage', {})
         self._output_tokens = usage.get('output_tokens', 0)
-
+        chunk = make_cc_chunk(
-        chunk = self._make_chunk(
+            self._id,
             delta={},
             finish_reason=_STOP_REASON_MAP.get(delta.get('stop_reason', ''), 'stop'),
+            model='claude',
         )
-        chunk['usage'] = _build_cc_usage(
+        chunk['usage'] = build_cc_usage(
             input_tokens=self._input_tokens,
             output_tokens=self._output_tokens,
         )
-        return [self._dump_chunk(chunk)]
+        return [chunk]
 
     def _make_chunk(self, delta: JsonDict, finish_reason: str | None = None) -> JsonDict:
         """构造标准 OpenAI Chat Completions chunk 对象。"""
-        choice: JsonDict = {'index': 0, 'delta': delta}
+        return make_cc_chunk(self._id, delta, finish_reason, model='claude')
-        if finish_reason:
-            choice['finish_reason'] = finish_reason
-        return {
-            'id': self._id,
-            'object': 'chat.completion.chunk',
-            'model': 'claude',
-            'choices': [choice],
-        }
-
-    @staticmethod
-    def _dump_chunk(chunk: JsonDict) -> str:
-        """统一序列化 chunk，方便上层直接写入 SSE data。"""
-        return json.dumps(chunk)
 
 
 # ═══════════════════════════════════════════════════════════
@@ -254,7 +213,7 @@ def _convert_request_message(message: Any) -> tuple[JsonDict | None, str | None]
     content = message.get('content', '')
 
     if role == 'system':
-        return None, _flatten_text(content)
+        return None, extract_text(content)
     if role == 'tool':
         return _convert_tool_role_message(message), None
 
@@ -301,7 +260,7 @@ def _append_tool_use_blocks(content: Any, tool_calls: list[Any]) -> list[JsonDic
             'type': 'tool_use',
             'id': tool_call.get('id', gen_id('toolu_')),
             'name': function_data.get('name', ''),
-            'input': _parse_tool_arguments(function_data.get('arguments', '{}')),
+            'input': parse_json_safe(function_data.get('arguments', '{}')),
         })
     return blocks
 
@@ -372,37 +331,12 @@ def _convert_tool_use_block(block: JsonDict, *, index: int) -> JsonDict:
     else:
         arguments_text = str(input_data)
 
-    return {
+    return build_cc_tool_call(
-        'index': index,
+        call_id=block.get('id', gen_id('toolu_')),
-        'id': block.get('id', gen_id('toolu_')),
+        name=tool_name,
-        'type': 'function',
+        arguments=arguments_text,
-        'function': {
+        index=index,
-            'name': tool_name,
+    )
-            'arguments': arguments_text,
-        },
-    }
-
-
-def _build_cc_message(content_text: str, reasoning_text: str, tool_calls: list[JsonDict]) -> JsonDict:
-    """构造 OpenAI CC 响应中的 assistant message。"""
-    message: JsonDict = {
-        'role': 'assistant',
-        'content': content_text or None,
-    }
-    if reasoning_text:
-        message['reasoning_content'] = reasoning_text
-    if tool_calls:
-        message['tool_calls'] = tool_calls
-    return message
-
-
-def _build_cc_usage(*, input_tokens: int, output_tokens: int) -> JsonDict:
-    """将 Anthropic usage 字段映射为 OpenAI usage。"""
-    return {
-        'prompt_tokens': input_tokens,
-        'completion_tokens': output_tokens,
-        'total_tokens': input_tokens + output_tokens,
-    }
 
 
 # ═══════════════════════════════════════════════════════════
@@ -410,35 +344,6 @@ def _build_cc_usage(*, input_tokens: int, output_tokens: int) -> JsonDict:
 # ═══════════════════════════════════════════════════════════
 
 
-def _parse_tool_arguments(arguments: Any) -> Any:
-    """将 tool_call.arguments 尽量解析为对象，供 Anthropic tool_use.input 使用。
-
-    Anthropic 的 `tool_use.input` 天然期望对象结构；如果这里直接保留原始字符串，
-    后续上游会把它当普通文本而不是工具参数对象。
-    """
-    if not isinstance(arguments, str):
-        return arguments if arguments is not None else {}
-    try:
-        return json.loads(arguments)
-    except json.JSONDecodeError:
-        return {}
-
-
-def _flatten_text(content: Any) -> str:
-    """将 content 扁平化为纯文本，主要用于 system 消息上提。"""
-    if isinstance(content, str):
-        return content
-    if isinstance(content, list):
-        parts: list[str] = []
-        for part in content:
-            if isinstance(part, str):
-                parts.append(part)
-            elif isinstance(part, dict) and part.get('type') == 'text':
-                parts.append(part.get('text', ''))
-        return '\n'.join(parts)
-    return str(content)
-
-
 def _convert_content(message: JsonDict) -> Any:
     """将 OpenAI 消息的 content 字段转换为 Anthropic 内容格式。"""
     content = message.get('content', '')
@@ -708,3 +613,78 @@ def _pick_window_anchor(refs: list[JsonDict], target: int) -> int | None:
         if 'cache_control' not in refs[i]:
             return i
     return None
+
+
+# ═══════════════════════════════════════════════════════════
+#  OutboundTransformer 实现: Anthropic Messages
+# ═══════════════════════════════════════════════════════════
+
+
+class AnthropicOutbound:
+    """Anthropic Messages 后端的出站转换器。
+
+    将 CC 格式转换为 Anthropic Messages 格式并处理响应。
+    """
+
+    def build_request(self, payload: JsonDict) -> JsonDict:
+        return cc_to_messages_request(payload)
+
+    def build_url(self, ctx) -> str:
+        return f'{ctx.target_url.rstrip("/")}/v1/messages'
+
+    def build_headers(self, ctx) -> dict[str, str]:
+        from utils.http import build_anthropic_headers
+        return build_anthropic_headers(ctx.api_key)
+
+    def parse_response(self, raw: JsonDict) -> JsonDict:
+        return messages_to_cc_response(raw)
+
+    def create_stream_processor(self) -> AnthropicStreamProcessor:
+        return AnthropicStreamProcessor()
+
+
+class AnthropicStreamProcessor:
+    """Anthropic SSE 流式处理器。
+
+    包装 iter_anthropic_sse + AnthropicStreamConverter，
+    将 Anthropic 事件流转换为 CC chunk。
+    """
+
+    def __init__(self):
+        self._converter = AnthropicStreamConverter()
+        self._input_tokens = 0
+        self._output_tokens = 0
+
+    def iter_events(self, response) -> Iterator:
+        from utils.http import iter_anthropic_sse
+        yield from iter_anthropic_sse(response)
+
+    def process_event(self, event: tuple) -> list[JsonDict]:
+        event_type, event_data = event
+        return self._converter.process_event(event_type, event_data)
+
+    def extract_usage(self, event: tuple) -> JsonDict | None:
+        event_type, event_data = event
+        if event_type == 'message_start':
+            message_usage = event_data.get('message', {}).get('usage', {})
+            if isinstance(message_usage, dict):
+                self._input_tokens = message_usage.get('input_tokens', 0)
+                return {
+                    'prompt_tokens': self._input_tokens,
+                    'completion_tokens': 0,
+                    'total_tokens': self._input_tokens,
+                }
+        elif event_type == 'message_delta':
+            delta_usage = event_data.get('usage', {})
+            if isinstance(delta_usage, dict):
+                completion = delta_usage.get('output_tokens', 0)
+                self._output_tokens = completion
+                return {
+                    'prompt_tokens': self._input_tokens,
+                    'completion_tokens': completion,
+                    'total_tokens': self._input_tokens + completion,
+                }
+        return None
+
+    def finalize(self) -> list[JsonDict]:
+        return []

adapters/cc_gemini_adapter.py

@@ -8,8 +8,17 @@ from __future__ import annotations
 
 import json
 import logging
-from typing import Any
+from typing import Any, Iterator
 
+from adapters.helpers import (
+    build_cc_message,
+    build_cc_response,
+    build_cc_tool_call,
+    build_cc_usage,
+    extract_text,
+    make_cc_chunk,
+    parse_json_safe,
+)
 from utils.http import gen_id
 
 JsonDict = dict[str, Any]
@@ -38,7 +47,7 @@ def cc_to_gemini_request(payload: JsonDict) -> JsonDict:
     for msg in messages:
         role = msg.get('role', '')
         if role in ('system', 'developer'):
-            system_parts.append(_flatten_text(msg.get('content', '')))
+            system_parts.append(extract_text(msg.get('content', '')))
             continue
         converted = _convert_message(msg)
         if converted:
@@ -84,21 +93,13 @@ def gemini_to_cc_response(data: JsonDict, request_id: str | None = None) -> Json
     else:
         finish_reason = _FINISH_REASON_MAP.get(finish, 'stop')
 
-    message: JsonDict = {'role': 'assistant', 'content': content_text or None}
+    return build_cc_response(
-    if reasoning_text:
+        response_id=request_id,
-        message['reasoning_content'] = reasoning_text
+        message=build_cc_message(content_text, reasoning_text, tool_calls),
-    if tool_calls:
+        finish_reason=finish_reason,
-        message['tool_calls'] = tool_calls
+        usage=_convert_usage(data.get('usageMetadata', {})),
-
+        model=data.get('modelVersion', 'gemini'),
-    usage = _convert_usage(data.get('usageMetadata', {}))
+    )
-
-    return {
-        'id': request_id,
-        'object': 'chat.completion',
-        'model': data.get('modelVersion', 'gemini'),
-        'choices': [{'index': 0, 'message': message, 'finish_reason': finish_reason}],
-        'usage': usage,
-    }
 
 
 # ═══════════════════════════════════════════════════════════
@@ -166,15 +167,7 @@ class GeminiStreamConverter:
         return results
 
     def _make_chunk(self, delta: JsonDict, finish_reason: str | None = None) -> JsonDict:
-        choice: JsonDict = {'index': 0, 'delta': delta}
+        return make_cc_chunk(self._id, delta, finish_reason, model='gemini')
-        if finish_reason:
-            choice['finish_reason'] = finish_reason
-        return {
-            'id': self._id,
-            'object': 'chat.completion.chunk',
-            'model': 'gemini',
-            'choices': [choice],
-        }
 
 
 # ═══════════════════════════════════════════════════════════
@@ -194,7 +187,7 @@ def _convert_message(msg: JsonDict) -> JsonDict | None:
             'parts': [{
                 'functionResponse': {
                     'name': msg.get('name', msg.get('tool_call_id', '')),
-                    'response': _parse_json_safe(msg.get('content', '')),
+                    'response': parse_json_safe(msg.get('content', ''), fallback={'result': msg.get('content', '')} if msg.get('content', '') else {}),
                 },
             }],
         }
@@ -221,7 +214,7 @@ def _convert_message(msg: JsonDict) -> JsonDict | None:
         parts.append({
             'functionCall': {
                 'name': func.get('name', ''),
-                'args': _parse_json_safe(func.get('arguments', '{}')),
+                'args': parse_json_safe(func.get('arguments', '{}'), fallback={}),
             },
         })
 
@@ -304,15 +297,12 @@ def _extract_parts(parts: list[Any]) -> tuple[str, str, list[JsonDict]]:
             text += part['text']
         elif 'functionCall' in part:
             fc = part['functionCall']
-            tool_calls.append({
+            tool_calls.append(build_cc_tool_call(
-                'index': len(tool_calls),
+                call_id=fc.get('id') or gen_id('call_'),
-                'id': fc.get('id') or gen_id('call_'),
+                name=fc.get('name', ''),
-                'type': 'function',
+                arguments=json.dumps(fc.get('args', {}), ensure_ascii=False),
-                'function': {
+                index=len(tool_calls),
-                    'name': fc.get('name', ''),
+            ))
-                    'arguments': json.dumps(fc.get('args', {}), ensure_ascii=False),
-                },
-            })
 
     return text, reasoning, tool_calls
 
@@ -322,12 +312,7 @@ def _convert_usage(meta: JsonDict) -> JsonDict:
     prompt = meta.get('promptTokenCount', 0)
     candidates = meta.get('candidatesTokenCount', 0)
     thoughts = meta.get('thoughtsTokenCount', 0)
-    completion = candidates + thoughts
+    return build_cc_usage(prompt, candidates + thoughts)
-    return {
-        'prompt_tokens': prompt,
-        'completion_tokens': completion,
-        'total_tokens': prompt + completion,
-    }
 
 
 def _merge_same_role(contents: list[JsonDict]) -> list[JsonDict]:
@@ -343,21 +328,65 @@ def _merge_same_role(contents: list[JsonDict]) -> list[JsonDict]:
     return merged
 
 
-def _flatten_text(content: Any) -> str:
-    if isinstance(content, str):
-        return content
-    if isinstance(content, list):
-        return '\n'.join(
-            p.get('text', '') if isinstance(p, dict) else str(p)
-            for p in content
-        )
-    return str(content)
 
 
-def _parse_json_safe(text: Any) -> Any:
+# ═══════════════════════════════════════════════════════════
-    if not isinstance(text, str):
+#  OutboundTransformer 实现: Gemini Contents
-        return text if text is not None else {}
+# ═══════════════════════════════════════════════════════════
-    try:
+
-        return json.loads(text)
+
-    except (json.JSONDecodeError, ValueError):
+class GeminiOutbound:
-        return {'result': text} if text else {}
+    """Gemini Contents 后端的出站转换器。
+
+    将 CC 格式转换为 Gemini generateContent 格式并处理响应。
+    """
+
+    def build_request(self, payload: JsonDict) -> JsonDict:
+        return cc_to_gemini_request(payload)
+
+    def build_url(self, ctx) -> str:
+        base = ctx.target_url.rstrip('/')
+        model = ctx.upstream_model
+        if ctx.is_stream:
+            return f'{base}/v1/models/{model}:streamGenerateContent?alt=sse'
+        return f'{base}/v1/models/{model}:generateContent'
+
+    def build_headers(self, ctx) -> dict[str, str]:
+        from utils.http import build_gemini_headers
+        return build_gemini_headers(ctx.api_key)
+
+    def parse_response(self, raw: JsonDict) -> JsonDict:
+        return gemini_to_cc_response(raw)
+
+    def create_stream_processor(self) -> GeminiStreamProcessor:
+        return GeminiStreamProcessor()
+
+
+class GeminiStreamProcessor:
+    """Gemini SSE 流式处理器。
+
+    包装 iter_gemini_sse + GeminiStreamConverter。
+    """
+
+    def __init__(self):
+        self._converter = GeminiStreamConverter()
+
+    def iter_events(self, response) -> Iterator:
+        from utils.http import iter_gemini_sse
+        yield from iter_gemini_sse(response)
+
+    def process_event(self, event: JsonDict) -> list[JsonDict]:
+        return self._converter.process_chunk(event)
+
+    def extract_usage(self, event: JsonDict) -> JsonDict | None:
+        usage_meta = event.get('usageMetadata') if isinstance(event, dict) else None
+        if isinstance(usage_meta, dict):
+            return {
+                'prompt_tokens': usage_meta.get('promptTokenCount', 0),
+                'completion_tokens': usage_meta.get('candidatesTokenCount', 0),
+                'total_tokens': usage_meta.get('totalTokenCount', 0),
+            }
+        return None
+
+    def finalize(self) -> list[JsonDict]:
+        return []

adapters/helpers.py

@@ -0,0 +1,155 @@
+"""适配器公共辅助函数
+
+收敛多个适配器都在重复实现的 CC 格式构建逻辑：
+- CC 消息/Usage/Tool Call/Stream Chunk 的标准构造
+- 内容扁平化、JSON 安全解析、工具输出序列化
+"""
+
+from __future__ import annotations
+
+import json
+from typing import Any
+
+from utils.http import gen_id
+
+JsonDict = dict[str, Any]
+
+
+# ═══════════════════════════════════════════════════════════
+#  CC 格式标准构造
+# ═══════════════════════════════════════════════════════════
+
+
+def build_cc_message(
+    content_text: str,
+    reasoning_text: str = '',
+    tool_calls: list[JsonDict] | None = None,
+) -> JsonDict:
+    """构造标准的 CC assistant 消息。"""
+    message: JsonDict = {
+        'role': 'assistant',
+        'content': content_text or None,
+    }
+    if reasoning_text:
+        message['reasoning_content'] = reasoning_text
+    if tool_calls:
+        message['tool_calls'] = tool_calls
+    return message
+
+
+def build_cc_usage(input_tokens: int, output_tokens: int) -> JsonDict:
+    """构造标准的 CC usage 字典。"""
+    return {
+        'prompt_tokens': input_tokens,
+        'completion_tokens': output_tokens,
+        'total_tokens': input_tokens + output_tokens,
+    }
+
+
+def build_cc_tool_call(
+    call_id: str,
+    name: str,
+    arguments: str,
+    *,
+    index: int | None = None,
+) -> JsonDict:
+    """构造标准的 CC tool_call 结构。"""
+    tc: JsonDict = {
+        'id': call_id or gen_id('call_'),
+        'type': 'function',
+        'function': {
+            'name': name,
+            'arguments': arguments,
+        },
+    }
+    if index is not None:
+        tc['index'] = index
+    return tc
+
+
+def make_cc_chunk(
+    chunk_id: str,
+    delta: JsonDict,
+    finish_reason: str | None = None,
+    model: str = '',
+) -> JsonDict:
+    """构造标准的 CC 流式 chunk。"""
+    choice: JsonDict = {'index': 0, 'delta': delta}
+    if finish_reason:
+        choice['finish_reason'] = finish_reason
+    return {
+        'id': chunk_id,
+        'object': 'chat.completion.chunk',
+        'model': model,
+        'choices': [choice],
+    }
+
+
+def build_cc_response(
+    response_id: str,
+    message: JsonDict,
+    finish_reason: str,
+    usage: JsonDict,
+    model: str = '',
+) -> JsonDict:
+    """构造标准的 CC 非流式响应。"""
+    return {
+        'id': response_id,
+        'object': 'chat.completion',
+        'model': model,
+        'choices': [{
+            'index': 0,
+            'message': message,
+            'finish_reason': finish_reason,
+        }],
+        'usage': usage,
+    }
+
+
+# ═══════════════════════════════════════════════════════════
+#  通用文本/JSON 处理
+# ═══════════════════════════════════════════════════════════
+
+
+def extract_text(content: Any) -> str:
+    """从多种内容格式中提取并拼接纯文本。
+
+    支持字符串、内容块列表（OpenAI/Anthropic/Responses 风格）。
+    """
+    if isinstance(content, str):
+        return content
+    if not isinstance(content, list):
+        return str(content) if content is not None else ''
+
+    parts: list[str] = []
+    for part in content:
+        if isinstance(part, str):
+            parts.append(part)
+        elif isinstance(part, dict):
+            part_type = part.get('type', '')
+            if part_type in ('text', 'output_text', 'input_text'):
+                parts.append(part.get('text', ''))
+            elif part_type == 'refusal':
+                parts.append(part.get('refusal', ''))
+            elif 'text' in part and not part_type:
+                parts.append(part['text'])
+    return '\n'.join(parts) if parts else ''
+
+
+def parse_json_safe(text: Any, fallback: Any = None) -> Any:
+    """安全解析 JSON，失败时返回 fallback。"""
+    if not isinstance(text, str):
+        return text if text is not None else (fallback if fallback is not None else {})
+    try:
+        return json.loads(text)
+    except (json.JSONDecodeError, ValueError):
+        return fallback if fallback is not None else {}
+
+
+def stringify_content(content: Any) -> str:
+    """将任意内容序列化为字符串。"""
+    if isinstance(content, str):
+        return content
+    if content is None:
+        return ''
+    return json.dumps(content, ensure_ascii=False)

adapters/openai_compat_fixer.py

@@ -13,7 +13,7 @@ from __future__ import annotations
 
 import json
 import logging
-from typing import Any
+from typing import Any, Iterator
 
 from utils.http import gen_id
 from utils.think_tag import extract_from_text
@@ -423,3 +423,60 @@ def _rewrite_function_call_finish_reason(choice: JsonDict) -> None:
     """将旧版 finish_reason=function_call 升级为 tool_calls。"""
     if choice.get('finish_reason') == 'function_call':
         choice['finish_reason'] = 'tool_calls'
+
+
+# ═══════════════════════════════════════════════════════════
+#  OutboundTransformer 实现: OpenAI Chat
+# ═══════════════════════════════════════════════════════════
+
+
+class OpenAIChatOutbound:
+    """OpenAI Chat Completions 后端的出站转换器。
+
+    由于 CC 本身就是 OpenAI Chat 格式，请求/响应转换主要做兼容性修复。
+    """
+
+    def build_request(self, payload: JsonDict) -> JsonDict:
+        return normalize_request(payload)
+
+    def build_url(self, ctx) -> str:
+        return f'{ctx.target_url.rstrip("/")}/v1/chat/completions'
+
+    def build_headers(self, ctx) -> dict[str, str]:
+        from utils.http import build_openai_headers
+        return build_openai_headers(ctx.api_key)
+
+    def parse_response(self, raw: JsonDict) -> JsonDict:
+        return fix_response(raw)
+
+    def create_stream_processor(self) -> OpenAIChatStreamProcessor:
+        return OpenAIChatStreamProcessor()
+
+
+class OpenAIChatStreamProcessor:
+    """OpenAI Chat SSE 流式处理器。
+
+    包装 iter_openai_sse + fix_stream_chunk + ThinkTagExtractor。
+    """
+
+    def __init__(self):
+        from utils.think_tag import ThinkTagExtractor
+        self._think_extractor = ThinkTagExtractor()
+
+    def iter_events(self, response) -> Iterator:
+        from utils.http import iter_openai_sse
+        for chunk in iter_openai_sse(response):
+            if chunk is None:
+                return
+            yield chunk
+
+    def process_event(self, event: JsonDict) -> list[JsonDict]:
+        chunk = fix_stream_chunk(event)
+        return list(self._think_extractor.process_chunk(chunk))
+
+    def extract_usage(self, event: JsonDict) -> JsonDict | None:
+        return event.get('usage')
+
+    def finalize(self) -> list[JsonDict]:
+        close_chunk = self._think_extractor.finalize()
+        return [close_chunk] if close_chunk else []

adapters/responses_cc_adapter.py

@@ -15,8 +15,18 @@ from __future__ import annotations
 
 import json
 from dataclasses import dataclass
-from typing import Any
+from typing import Any, Iterator
 
+from adapters.helpers import (
+    build_cc_message,
+    build_cc_response,
+    build_cc_tool_call,
+    build_cc_usage,
+    extract_text,
+    make_cc_chunk,
+    stringify_content,
+)
+from adapters.unified import UnifiedUsage
 from utils.http import gen_id
 
 JsonDict = dict[str, Any]
@@ -85,7 +95,7 @@ def cc_to_responses(cc_resp: JsonDict, model: str = '') -> JsonDict:
         'status': _response_status_from_finish_reason(finish_reason),
         'model': model or cc_resp.get('model', ''),
         'output': _build_responses_output(message),
-        'usage': _build_responses_usage(cc_resp.get('usage', {})),
+        'usage': UnifiedUsage.from_cc_dict(cc_resp.get('usage', {})).to_responses_dict(),
     }
 
 
@@ -94,31 +104,18 @@ def responses_to_cc_response(response_data: JsonDict, model: str = '') -> JsonDi
     output_items = response_data.get('output', [])
     content_text, reasoning_text, tool_calls = _collect_cc_parts_from_responses_output(output_items)
     finish_reason = _cc_finish_reason_from_responses(response_data, tool_calls)
-    message = {
-        'role': 'assistant',
-        'content': content_text or None,
-    }
-    if reasoning_text:
-        message['reasoning_content'] = reasoning_text
-    if tool_calls:
-        message['tool_calls'] = tool_calls
-
     usage = response_data.get('usage', {})
-    return {
+
-        'id': response_data.get('id', gen_id('chatcmpl-')),
+    return build_cc_response(
-        'object': 'chat.completion',
+        response_id=response_data.get('id', gen_id('chatcmpl-')),
-        'model': model or response_data.get('model', ''),
+        message=build_cc_message(content_text, reasoning_text, tool_calls),
-        'choices': [{
+        finish_reason=finish_reason,
-            'index': 0,
+        usage=build_cc_usage(
-            'message': message,
+            input_tokens=usage.get('input_tokens', 0),
-            'finish_reason': finish_reason,
+            output_tokens=usage.get('output_tokens', 0),
-        }],
+        ),
-        'usage': {
+        model=model or response_data.get('model', ''),
-            'prompt_tokens': usage.get('input_tokens', 0),
+    )
-            'completion_tokens': usage.get('output_tokens', 0),
-            'total_tokens': usage.get('total_tokens', 0),
-        },
-    }
 
 
 # ═══════════════════════════════════════════════════════════
@@ -658,15 +655,7 @@ class ResponsesToCCStreamConverter:
 
     def _make_chunk(self, delta: JsonDict, finish_reason: str | None = None) -> JsonDict:
         """构造标准 Chat Completions chunk。"""
-        choice: JsonDict = {'index': 0, 'delta': delta}
+        return make_cc_chunk(self._id, delta, finish_reason, model=self._model)
-        if finish_reason:
-            choice['finish_reason'] = finish_reason
-        return {
-            'id': self._id,
-            'object': 'chat.completion.chunk',
-            'model': self._model,
-            'choices': [choice],
-        }
 
 
 # ═══════════════════════════════════════════════════════════
@@ -715,7 +704,7 @@ def _append_responses_input_item(
     content = message.get('content')
 
     if role == 'system':
-        text = _content_to_text(content)
+        text = extract_text(content)
         if text:
             instructions.append(text)
         return
@@ -724,11 +713,11 @@ def _append_responses_input_item(
         input_items.append({
             'type': 'function_call_output',
             'call_id': message.get('tool_call_id', ''),
-            'output': _stringify_output(content),
+            'output': stringify_content(content),
         })
         return
 
-    text = _content_to_text(content)
+    text = extract_text(content)
     has_tool_calls = bool(message.get('tool_calls'))
 
     if role == 'assistant' and has_tool_calls:
@@ -771,7 +760,7 @@ def _convert_input_items(items: list[Any], messages: list[JsonDict]) -> None:
         if role and not item_type:
             msg: JsonDict = {
                 'role': role,
-                'content': _normalize_simple_content(item.get('content', '')),
+                'content': extract_text(item.get('content', '')),
             }
             if role == 'assistant' and pending_reasoning:
                 msg['reasoning_content'] = pending_reasoning
@@ -810,7 +799,7 @@ def _append_message_item(items: list[Any], *, start: int, messages: list[JsonDic
     """将一个 message 项及其后续连续 function_call 项合并成一条消息。"""
     item = items[start]
     role = item.get('role', 'assistant')
-    content = _extract_text(item.get('content', []))
+    content = extract_text(item.get('content', []))
     message: JsonDict = {'role': role, 'content': content or ''}
 
     if role == 'assistant':
@@ -828,7 +817,11 @@ def _append_message_item(items: list[Any], *, start: int, messages: list[JsonDic
 
 def _append_function_call_item(item: JsonDict, messages: list[JsonDict]) -> None:
     """将独立的 Responses `function_call` 项挂接到最近的 assistant 消息上。"""
-    tool_call = _build_cc_tool_call(item)
+    tool_call = build_cc_tool_call(
+        call_id=item.get('call_id') or gen_id('call_'),
+        name=item.get('name', ''),
+        arguments=item.get('arguments', '{}'),
+    )
 
     if messages and messages[-1]['role'] == 'assistant':
         messages[-1].setdefault('tool_calls', []).append(tool_call)
@@ -851,12 +844,6 @@ def _convert_function_call_output_item(item: JsonDict) -> JsonDict:
     }
 
 
-def _normalize_simple_content(content: Any) -> str:
-    """将简单 content 载荷规范化为纯文本字符串。"""
-    if isinstance(content, list):
-        return _extract_text(content) or ''
-    return str(content) if content is not None else ''
-
 
 def _collect_function_calls(items: list[Any], start: int) -> tuple[list[JsonDict], int]:
     """收集从指定位置开始连续出现的 `function_call` 项。"""
@@ -865,24 +852,17 @@ def _collect_function_calls(items: list[Any], start: int) -> tuple[list[JsonDict
     while index < len(items):
         next_item = items[index]
         if isinstance(next_item, dict) and next_item.get('type') == 'function_call':
-            tool_calls.append(_build_cc_tool_call(next_item))
+            tool_calls.append(build_cc_tool_call(
+                call_id=next_item.get('call_id') or gen_id('call_'),
+                name=next_item.get('name', ''),
+                arguments=next_item.get('arguments', '{}'),
+            ))
             index += 1
         else:
             break
     return tool_calls, index - start
 
 
-def _build_cc_tool_call(item: JsonDict) -> JsonDict:
-    """将单个 Responses `function_call` 项转换为 CC `tool_call` 结构。"""
-    return {
-        'id': item.get('call_id') or gen_id('call_'),
-        'type': 'function',
-        'function': {
-            'name': item.get('name', ''),
-            'arguments': item.get('arguments', '{}'),
-        },
-    }
-
 
 # ═══════════════════════════════════════════════════════════
 #  非流式响应转换辅助
@@ -936,14 +916,6 @@ def _make_function_call_output_item(tool_call: JsonDict) -> JsonDict:
     }
 
 
-def _build_responses_usage(usage: JsonDict) -> JsonDict:
-    """将 Chat Completions 的 usage 字段映射为 Responses usage 结构。"""
-    return {
-        'input_tokens': usage.get('prompt_tokens', 0),
-        'output_tokens': usage.get('completion_tokens', 0),
-        'total_tokens': usage.get('total_tokens', 0),
-    }
-
 
 def _collect_cc_parts_from_responses_output(output_items: Any) -> tuple[str, str, list[JsonDict]]:
     """从 Responses `output` 中提取文本、思考摘要和工具调用。"""
@@ -959,11 +931,16 @@ def _collect_cc_parts_from_responses_output(output_items: Any) -> tuple[str, str
             continue
         item_type = item.get('type', '')
         if item_type == 'message':
-            content_text += _extract_text(item.get('content', []))
+            content_text += extract_text(item.get('content', []))
         elif item_type == 'reasoning':
             reasoning_text += _extract_reasoning_text(item)
         elif item_type == 'function_call':
-            tool_calls.append(_build_cc_tool_call_from_responses_output(item, index=len(tool_calls)))
+            tool_calls.append(build_cc_tool_call(
+                call_id=item.get('call_id') or gen_id('call_'),
+                name=item.get('name', ''),
+                arguments=item.get('arguments', '{}'),
+                index=len(tool_calls),
+            ))
 
     return content_text, reasoning_text, tool_calls
 
@@ -980,18 +957,6 @@ def _extract_reasoning_text(item: JsonDict) -> str:
     return ''.join(texts)
 
 
-def _build_cc_tool_call_from_responses_output(item: JsonDict, *, index: int) -> JsonDict:
-    """将 Responses `function_call` 输出项转换为 CC `tool_call`。"""
-    return {
-        'index': index,
-        'id': item.get('call_id') or gen_id('call_'),
-        'type': 'function',
-        'function': {
-            'name': item.get('name', ''),
-            'arguments': item.get('arguments', '{}'),
-        },
-    }
-
 
 def _cc_finish_reason_from_responses(response_data: JsonDict, tool_calls: list[JsonDict]) -> str:
     """根据 Responses 完成状态推断聊天补全的 finish_reason。"""
@@ -1017,57 +982,7 @@ def _map_anthropic_stop_reason(stop_reason: str) -> str:
 # ═══════════════════════════════════════════════════════════
 
 
-def _extract_text(content: Any) -> str:
-    """从多种内容块结构中提取并拼接纯文本。"""
-    if isinstance(content, str):
-        return content
-    if not isinstance(content, list):
-        return str(content) if content else ''
 
-    texts: list[str] = []
-    for part in content:
-        if isinstance(part, str):
-            texts.append(part)
-        elif isinstance(part, dict):
-            part_type = part.get('type', '')
-            if part_type in ('output_text', 'input_text', 'text'):
-                texts.append(part.get('text', ''))
-            elif part_type == 'refusal':
-                texts.append(part.get('refusal', ''))
-    return '\n'.join(texts) if texts else ''
-
-
-def _content_to_text(content: Any) -> str:
-    """将任意 content 载荷转换为单个字符串。"""
-    if isinstance(content, str):
-        return content
-    if isinstance(content, list):
-        return _extract_text(content)
-    return str(content) if content is not None else ''
-
-
-def _content_to_responses_parts(content: Any, role: str = 'user') -> list[JsonDict]:
-    """将普通消息内容转换为 Responses 内容块数组。
-
-    assistant 消息使用 output_text，其他角色使用 input_text。
-    """
-    if isinstance(content, list):
-        text = _extract_text(content)
-    else:
-        text = _content_to_text(content)
-    if not text:
-        return []
-    part_type = 'output_text' if role == 'assistant' else 'input_text'
-    return [{'type': part_type, 'text': text}]
-
-
-def _stringify_output(content: Any) -> str:
-    """将工具输出统一序列化为字符串，便于放入 `function_call_output`。"""
-    if isinstance(content, str):
-        return content
-    if content is None:
-        return ''
-    return json.dumps(content, ensure_ascii=False) if not isinstance(content, str) else content
 
 
 def _build_responses_function_call_item(tool_call: JsonDict) -> JsonDict:
@@ -1081,6 +996,165 @@ def _build_responses_function_call_item(tool_call: JsonDict) -> JsonDict:
     }
 
 
+# ═══════════════════════════════════════════════════════════
+#  OutboundTransformer 实现: Responses
+# ═══════════════════════════════════════════════════════════
+
+
+class ResponsesOutbound:
+    """OpenAI Responses 后端的出站转换器。
+
+    将 CC 格式转换为 Responses 格式并处理响应。
+    """
+
+    def build_request(self, payload: JsonDict) -> JsonDict:
+        return cc_to_responses_request(payload)
+
+    def build_url(self, ctx) -> str:
+        return f'{ctx.target_url.rstrip("/")}/v1/responses'
+
+    def build_headers(self, ctx) -> dict[str, str]:
+        from utils.http import build_openai_headers
+        return build_openai_headers(ctx.api_key)
+
+    def parse_response(self, raw: JsonDict) -> JsonDict:
+        return responses_to_cc_response(raw)
+
+    def create_stream_processor(self) -> ResponsesStreamProcessorForCC:
+        return ResponsesStreamProcessorForCC()
+
+
+class ResponsesStreamProcessorForCC:
+    """Responses SSE → CC chunk 流式处理器。
+
+    用于 /v1/chat/completions -> /v1/responses 的桥接路径。
+    """
+
+    def __init__(self):
+        self._converter = ResponsesToCCStreamConverter()
+
+    def iter_events(self, response) -> Iterator:
+        from utils.http import iter_responses_sse
+        yield from iter_responses_sse(response)
+
+    def process_event(self, event: tuple) -> list[JsonDict]:
+        event_type, event_data = event
+        return self._converter.process_event(event_type, event_data)
+
+    def extract_usage(self, event: tuple) -> JsonDict | None:
+        from adapters.unified import extract_responses_usage
+        event_type, event_data = event
+        extracted = extract_responses_usage(event_data)
+        if extracted:
+            return {
+                'prompt_tokens': extracted.get('input_tokens', 0),
+                'completion_tokens': extracted.get('output_tokens', 0),
+                'total_tokens': extracted.get('total_tokens', 0),
+            }
+        return None
+
+    def finalize(self) -> list[JsonDict]:
+        return []
+
+
+class ResponsesNativeOutbound:
+    """Responses 后端原生透传的出站转换器。
+
+    当 /v1/responses → /v1/responses 时直接透传，不经过 CC 中间格式。
+    """
+
+    def build_request(self, payload: JsonDict) -> JsonDict:
+        return payload
+
+    def build_url(self, ctx) -> str:
+        return f'{ctx.target_url.rstrip("/")}/v1/responses'
+
+    def build_headers(self, ctx) -> dict[str, str]:
+        from utils.http import build_openai_headers
+        return build_openai_headers(ctx.api_key)
+
+    def parse_response(self, raw: JsonDict) -> JsonDict:
+        return raw
+
+    def create_stream_processor(self) -> ResponsesNativeStreamProcessor:
+        return ResponsesNativeStreamProcessor()
+
+
+class ResponsesNativeStreamProcessor:
+    """Responses 原生 SSE 透传流式处理器。
+
+    上游就是 Responses 格式，只需透传事件并做轻量模型名改写。
+    每个事件作为 SSE 字符串直接返回。
+    """
+
+    def iter_events(self, response) -> Iterator:
+        from utils.http import iter_responses_sse
+        yield from iter_responses_sse(response)
+
+    def process_event(self, event: tuple) -> list[JsonDict]:
+        event_type, event_data = event
+        return [{'_sse_event_type': event_type, **event_data}]
+
+    def extract_usage(self, event: tuple) -> JsonDict | None:
+        from adapters.unified import extract_responses_usage
+        _, event_data = event
+        return extract_responses_usage(event_data)
+
+    def finalize(self) -> list[JsonDict]:
+        return []
+
+
+class AnthropicOutboundForResponses:
+    """Anthropic 后端的出站转换器（用于 /v1/responses 路由）。
+
+    流式处理直接将 Anthropic SSE → Responses SSE，
+    跳过 CC 中间态以保留原始时序。
+    """
+
+    def build_request(self, payload: JsonDict) -> JsonDict:
+        from adapters.cc_anthropic_adapter import cc_to_messages_request
+        return cc_to_messages_request(payload)
+
+    def build_url(self, ctx) -> str:
+        return f'{ctx.target_url.rstrip("/")}/v1/messages'
+
+    def build_headers(self, ctx) -> dict[str, str]:
+        from utils.http import build_anthropic_headers
+        return build_anthropic_headers(ctx.api_key)
+
+    def parse_response(self, raw: JsonDict) -> JsonDict:
+        from adapters.cc_anthropic_adapter import messages_to_cc_response
+        return messages_to_cc_response(raw)
+
+    def create_stream_processor(self) -> AnthropicToResponsesStreamProcessor:
+        return AnthropicToResponsesStreamProcessor()
+
+
+class AnthropicToResponsesStreamProcessor:
+    """Anthropic SSE → Responses SSE 直接转换的流式处理器。
+
+    跳过 CC 中间态，直接将 Anthropic 事件映射为 Responses 事件。
+    返回的 chunk 是 SSE 字符串。
+    """
+
+    def __init__(self):
+        self._converter = ResponsesStreamConverter()
+
+    def iter_events(self, response) -> Iterator:
+        from utils.http import iter_anthropic_sse
+        yield from iter_anthropic_sse(response)
+
+    def process_event(self, event: tuple) -> list[str]:
+        event_type, event_data = event
+        return self._converter.process_anthropic_event(event_type, event_data)
+
+    def extract_usage(self, event: tuple) -> JsonDict | None:
+        return None
+
+    def finalize(self) -> list[str]:
+        return self._converter.finalize()
+
+
 def _convert_cc_tools_to_responses(tools: Any) -> list[JsonDict]:
     """将聊天补全风格的工具定义转换为 Responses `tools` 列表。"""
     if not isinstance(tools, list):

adapters/unified.py

@@ -0,0 +1,354 @@
+"""统一中间格式与转换器接口
+
+定义项目中所有 API 格式共用的中间表示和转换器协议：
+- UnifiedRequest / UnifiedResponse: 统一的请求/响应数据结构
+- InboundTransformer / OutboundTransformer: 入站/出站转换器接口
+- StreamProcessor: 流式事件处理器接口
+- ClientFormatter: 客户端响应格式化接口
+"""
+
+from __future__ import annotations
+
+import json
+import logging
+from dataclasses import dataclass, field
+from typing import Any, Iterator, Protocol
+
+from flask import Response, jsonify
+
+import settings
+from utils.http import forward_request, gen_id, sse_response
+from utils.request_logger import (
+    append_client_event,
+    append_upstream_event,
+    attach_client_response,
+    attach_error,
+    attach_upstream_request,
+    attach_upstream_response,
+    finalize_turn,
+    set_stream_summary,
+)
+from utils.usage_tracker import usage_tracker
+
+logger = logging.getLogger(__name__)
+
+JsonDict = dict[str, Any]
+
+
+# ═══════════════════════════════════════════════════════════
+#  统一数据模型
+# ═══════════════════════════════════════════════════════════
+
+
+@dataclass
+class UnifiedUsage:
+    """标准化的令牌用量统计。"""
+
+    input_tokens: int = 0
+    output_tokens: int = 0
+    total_tokens: int = 0
+
+    def to_cc_dict(self) -> JsonDict:
+        return {
+            'prompt_tokens': self.input_tokens,
+            'completion_tokens': self.output_tokens,
+            'total_tokens': self.total_tokens,
+        }
+
+    def to_responses_dict(self) -> JsonDict:
+        return {
+            'input_tokens': self.input_tokens,
+            'output_tokens': self.output_tokens,
+            'total_tokens': self.total_tokens,
+        }
+
+    @classmethod
+    def from_cc_dict(cls, d: JsonDict) -> UnifiedUsage:
+        return cls(
+            input_tokens=d.get('prompt_tokens', 0),
+            output_tokens=d.get('completion_tokens', 0),
+            total_tokens=d.get('total_tokens', 0),
+        )
+
+    @classmethod
+    def from_responses_dict(cls, d: JsonDict) -> UnifiedUsage:
+        return cls(
+            input_tokens=d.get('input_tokens', 0),
+            output_tokens=d.get('output_tokens', 0),
+            total_tokens=d.get('total_tokens', 0),
+        )
+
+
+# ═══════════════════════════════════════════════════════════
+#  转换器接口
+# ═══════════════════════════════════════════════════════════
+
+
+class OutboundTransformer(Protocol):
+    """出站转换器：将 CC 中间格式转换为上游后端格式。
+
+    所有后端（OpenAI Chat / Responses / Anthropic / Gemini）各实现一套，
+    内部复用各自现有的适配器函数。
+    """
+
+    def build_request(self, payload: JsonDict) -> JsonDict:
+        """将 CC 格式请求体转换为上游格式请求体。"""
+        ...
+
+    def build_url(self, ctx: Any) -> str:
+        """根据路由上下文构建上游请求 URL。"""
+        ...
+
+    def build_headers(self, ctx: Any) -> JsonDict:
+        """根据路由上下文构建上游请求头。"""
+        ...
+
+    def parse_response(self, raw: JsonDict) -> JsonDict:
+        """将上游非流式响应转换回 CC 格式。"""
+        ...
+
+    def create_stream_processor(self) -> StreamProcessor:
+        """创建该后端对应的流式事件处理器。"""
+        ...
+
+
+class StreamProcessor(Protocol):
+    """流式事件处理器接口。
+
+    每个后端的 SSE 格式不同，StreamProcessor 封装了具体的迭代与转换逻辑，
+    让通用流式处理器不必关心后端差异。
+    """
+
+    def iter_events(self, response: Any) -> Iterator:
+        """从上游 HTTP 响应中迭代原始事件。"""
+        ...
+
+    def process_event(self, event: Any) -> list:
+        """将单个上游事件转换为输出项列表。
+
+        返回值通常是 list[JsonDict]（CC chunk），
+        但 Anthropic→Responses 路径返回 list[str]（SSE 字符串）。
+        """
+        ...
+
+    def extract_usage(self, event: Any) -> JsonDict | None:
+        """从上游事件中提取用量信息（如果有的话）。"""
+        ...
+
+    def finalize(self) -> list:
+        """流结束时产出的收尾项。"""
+        ...
+
+
+class ClientFormatter(Protocol):
+    """客户端响应格式化器。
+
+    根据客户端期望的 API 格式（CC 或 Responses），将通用的处理结果
+    格式化为最终返回给客户端的形态。
+    """
+
+    def format_response(self, cc_response: JsonDict, model: str) -> JsonDict:
+        """格式化非流式响应。"""
+        ...
+
+    def wrap_stream_item(self, item: Any) -> str:
+        """将单个流式输出项包装为 SSE 字符串。"""
+        ...
+
+    def format_error(self, message: str) -> str:
+        """构造流式错误消息。"""
+        ...
+
+    def format_done(self) -> str | None:
+        """构造流结束标记（CC 返回 [DONE]，Responses 返回 None）。"""
+        ...
+
+    def start_events(self) -> list[str]:
+        """流开始前的初始事件（Responses 返回 response.created）。"""
+        ...
+
+    @property
+    def usage_input_key(self) -> str:
+        """usage 中输入令牌的字段名。"""
+        ...
+
+    @property
+    def usage_output_key(self) -> str:
+        """usage 中输出令牌的字段名。"""
+        ...
+
+
+# ═══════════════════════════════════════════════════════════
+#  通用请求/响应处理器
+# ═══════════════════════════════════════════════════════════
+
+
+def _dbg(message: str) -> None:
+    if settings.get_debug_mode() in ('simple', 'verbose'):
+        logger.info('[通用调试] %s', message)
+
+
+def extract_responses_usage(event_data: JsonDict) -> JsonDict | None:
+    """从原生 Responses 事件中提取 usage（公共辅助）。"""
+    if not isinstance(event_data, dict):
+        return None
+    usage = event_data.get('usage')
+    if isinstance(usage, dict):
+        return usage
+    response_obj = event_data.get('response')
+    if isinstance(response_obj, dict):
+        nested_usage = response_obj.get('usage')
+        if isinstance(nested_usage, dict):
+            return nested_usage
+    return None
+
+
+def handle_non_stream(
+    ctx: Any,
+    outbound: OutboundTransformer,
+    client_fmt: ClientFormatter,
+    payload: JsonDict,
+    turn: JsonDict | None,
+) -> Response:
+    """通用非流式处理器。
+
+    替代 chat.py 和 responses.py 中的 8 个 _handle_xxx_non_stream 函数。
+    """
+    from routes.common import apply_body_modifications, apply_header_modifications, log_usage
+
+    upstream_payload = outbound.build_request(payload)
+    url = outbound.build_url(ctx)
+    headers = outbound.build_headers(ctx)
+    upstream_payload = apply_body_modifications(upstream_payload, ctx.body_modifications)
+    headers = apply_header_modifications(headers, ctx.header_modifications)
+
+    upstream_payload['stream'] = False
+    attach_upstream_request(turn, upstream_payload, headers)
+    resp, err = forward_request(url, headers, upstream_payload)
+    if err:
+        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
+        finalize_turn(turn)
+        return err
+
+    raw = resp.json()
+    attach_upstream_response(turn, raw)
+    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
+
+    cc_response = outbound.parse_response(raw)
+    result = client_fmt.format_response(cc_response, ctx.client_model)
+
+    _dbg('格式化后响应=' + json.dumps(result, ensure_ascii=False, default=str)[:1000])
+    usage_data = result.get('usage', {})
+    log_usage('通用', usage_data, input_key=client_fmt.usage_input_key, output_key=client_fmt.usage_output_key)
+    usage_tracker.record(
+        ctx.client_model,
+        usage_data,
+        input_key=client_fmt.usage_input_key,
+        output_key=client_fmt.usage_output_key,
+    )
+    attach_client_response(turn, result)
+    finalize_turn(turn, usage=usage_data)
+    return jsonify(result)
+
+
+def handle_stream(
+    ctx: Any,
+    outbound: OutboundTransformer,
+    client_fmt: ClientFormatter,
+    payload: JsonDict,
+    turn: JsonDict | None,
+) -> Response:
+    """通用流式处理器。
+
+    替代 chat.py 和 responses.py 中的 8 个 _handle_xxx_stream 函数。
+    """
+    from routes.common import apply_body_modifications, apply_header_modifications
+
+    upstream_payload = outbound.build_request(payload)
+    url = outbound.build_url(ctx)
+    headers = outbound.build_headers(ctx)
+    upstream_payload = apply_body_modifications(upstream_payload, ctx.body_modifications)
+    headers = apply_header_modifications(headers, ctx.header_modifications)
+
+    upstream_payload['stream'] = True
+    processor = outbound.create_stream_processor()
+
+    def generate():
+        for start_evt in client_fmt.start_events():
+            yield start_evt
+
+        attach_upstream_request(turn, upstream_payload, headers)
+        resp, err = forward_request(url, headers, upstream_payload, stream=True)
+        if err:
+            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
+            set_stream_summary(turn, {'status': 'error'})
+            finalize_turn(turn)
+            yield client_fmt.format_error(str(err))
+            return
+
+        event_count = 0
+        client_items: list[str] = []
+        last_usage: JsonDict | None = None
+
+        for event in processor.iter_events(resp):
+            append_upstream_event(turn, {'type': 'upstream_event', 'data': event})
+
+            extracted = processor.extract_usage(event)
+            if extracted is not None:
+                last_usage = extracted
+
+            if event_count < 10:
+                _dbg(
+                    f'上游事件#{event_count}='
+                    + json.dumps(event, ensure_ascii=False, default=str)[:500]
+                )
+
+            for chunk in processor.process_event(event):
+                if isinstance(chunk, dict):
+                    chunk['model'] = ctx.client_model
+                wrapped = client_fmt.wrap_stream_item(chunk)
+                client_items.append(wrapped)
+                append_client_event(turn, {'type': 'stream_item', 'data': chunk})
+                if event_count < 10:
+                    _dbg(
+                        f'返回片段#{event_count}='
+                        + json.dumps(chunk, ensure_ascii=False, default=str)[:500]
+                    )
+                yield wrapped
+
+            event_count += 1
+
+        for chunk in processor.finalize():
+            if isinstance(chunk, dict):
+                chunk['model'] = ctx.client_model
+            wrapped = client_fmt.wrap_stream_item(chunk)
+            client_items.append(wrapped)
+            append_client_event(turn, {'type': 'stream_item', 'data': chunk})
+            yield wrapped
+
+        done = client_fmt.format_done()
+        if done:
+            append_client_event(turn, {'type': 'done'})
+            yield done
+
+        _dbg(f'流式响应结束，共 {event_count} 个事件')
+        usage_tracker.record(
+            ctx.client_model,
+            last_usage,
+            input_key=client_fmt.usage_input_key,
+            output_key=client_fmt.usage_output_key,
+        )
+        set_stream_summary(turn, {
+            'event_count': event_count,
+            'client_item_count': len(client_items),
+            'usage': last_usage,
+        })
+        attach_client_response(turn, {
+            'type': 'stream.summary',
+            'model': ctx.client_model,
+            'event_count': len(client_items),
+            'usage': last_usage,
+        })
+        finalize_turn(turn, usage=last_usage)
+
+    return sse_response(generate())

routes/chat.py

@@ -1,8 +1,7 @@
 """路由: /v1/chat/completions
 
 处理 Cursor 发来的 OpenAI Chat Completions 格式请求。
-根据模型映射的后端类型，转发到 OpenAI 兼容接口、Anthropic Messages 接口，
+根据模型映射的后端类型，通过统一的出站转换器转发到不同后端。
-或原生 OpenAI Responses 接口。
 """
 
 from __future__ import annotations
@@ -11,103 +10,33 @@ import json
 import logging
 from typing import Any
 
-import settings
 from flask import Blueprint, jsonify, request
 
-from adapters.cc_anthropic_adapter import (
+from adapters.openai_compat_fixer import normalize_request
-    AnthropicStreamConverter,
+from adapters.responses_cc_adapter import responses_to_cc
-    cc_to_messages_request,
+from adapters.unified import handle_non_stream, handle_stream
-    messages_to_cc_response,
-)
-from adapters.cc_gemini_adapter import (
-    GeminiStreamConverter,
-    cc_to_gemini_request,
-    gemini_to_cc_response,
-)
-from adapters.openai_compat_fixer import fix_response, fix_stream_chunk, normalize_request
-from adapters.responses_cc_adapter import (
-    ResponsesToCCStreamConverter,
-    cc_to_responses_request,
-    responses_to_cc,
-    responses_to_cc_response,
-)
-from config import Config
 from routes.common import (
-    RouteContext,
+    CCClientFormatter,
-    apply_body_modifications,
-    apply_header_modifications,
-    build_anthropic_target,
-    build_gemini_target,
-    build_openai_target,
-    build_responses_target,
     build_route_context,
-    chat_error_chunk,
+    get_outbound,
-    inject_instructions_anthropic,
     inject_instructions_cc,
-    inject_instructions_responses,
     log_route_context,
-    log_usage,
-    sse_data_message,
 )
-from utils.http import (
+from utils.request_logger import start_turn
-    forward_request,
-    gen_id,
-    iter_anthropic_sse,
-    iter_gemini_sse,
-    iter_openai_sse,
-    iter_responses_sse,
-    sse_response,
-)
-from utils.request_logger import (
-    append_client_event,
-    append_upstream_event,
-    attach_client_response,
-    attach_error,
-    attach_upstream_request,
-    attach_upstream_response,
-    finalize_turn,
-    set_stream_summary,
-    start_turn,
-)
-from utils.think_tag import ThinkTagExtractor
 from utils.thinking_cache import thinking_cache
-from utils.usage_tracker import usage_tracker
 
 logger = logging.getLogger(__name__)
 
 bp = Blueprint('chat', __name__)
 
 
-def _dbg(message: str) -> None:
-    """仅在调试模式下输出详细日志。"""
-    if settings.get_debug_mode() in ('simple', 'verbose'):
-        logger.info('[聊天补全调试] %s', message)
-
-
-def _extract_responses_usage(event_data: dict[str, Any]) -> dict[str, Any] | None:
-    """从原生 Responses 事件中提取 usage。
-
-    `/v1/chat/completions -> /v1/responses` 的桥接流式路径也需要读取 usage，
-    因此在本文件保留一个本地辅助函数，避免依赖其他路由模块的私有实现。
-    """
-    if not isinstance(event_data, dict):
-        return None
-    usage = event_data.get('usage')
-    if isinstance(usage, dict):
-        return usage
-    response_obj = event_data.get('response')
-    if isinstance(response_obj, dict):
-        nested_usage = response_obj.get('usage')
-        if isinstance(nested_usage, dict):
-            return nested_usage
-    return None
-
-
 @bp.route('/v1/chat/completions', methods=['POST'])
 def chat_completions():
     """处理聊天补全请求并按模型映射分发到不同后端。"""
     original_payload = request.get_json(force=True)
-    payload, message_count = _normalize_chat_payload(json.loads(json.dumps(original_payload, ensure_ascii=False, default=str)))
+    payload, message_count = _normalize_chat_payload(
+        json.loads(json.dumps(original_payload, ensure_ascii=False, default=str))
+    )
 
     client_model = payload.get('model', 'unknown')
     is_stream = payload.get('stream', False)
@@ -127,23 +56,38 @@ def chat_completions():
     log_route_context('聊天补全', ctx, extra=f'消息数={message_count}')
     _log_messages(payload)
 
-    if ctx.backend != 'responses':
+    payload['model'] = ctx.upstream_model
-        payload['messages'] = thinking_cache.inject(payload.get('messages', []))
+    payload = normalize_request(payload)
+    payload['messages'] = thinking_cache.inject(payload.get('messages', []))
+    payload = inject_instructions_cc(payload, ctx.custom_instructions, ctx.instructions_position)
 
-    if ctx.backend == 'openai':
+    outbound = get_outbound(ctx.backend)
-        return _handle_openai_backend(ctx, payload, turn)
+    client_fmt = CCClientFormatter()
-    if ctx.backend == 'responses':
+
-        return _handle_responses_backend(ctx, payload, turn)
+    if ctx.is_stream:
-    if ctx.backend == 'gemini':
+        result = handle_stream(ctx, outbound, client_fmt, payload, turn)
-        return _handle_gemini_backend(ctx, payload, turn)
+    else:
-    return _handle_anthropic_backend(ctx, payload, turn)
+        result = handle_non_stream(ctx, outbound, client_fmt, payload, turn)
+
+    if not ctx.is_stream and isinstance(result, tuple):
+        response_data = result
+    elif hasattr(result, 'json'):
+        try:
+            response_data = result.get_json(silent=True) or {}
+        except Exception:
+            response_data = {}
+    else:
+        response_data = {}
+
+    _try_cache_thinking(response_data)
+    return result
 
 
 def _normalize_chat_payload(payload: dict[str, Any]) -> tuple[dict[str, Any], int]:
     """整理聊天补全入口的请求体。
 
-    这里保留了一层兼容逻辑：当 Cursor 或调用方把 Responses 格式误发到
+    当 Cursor 或调用方把 Responses 格式误发到 `/v1/chat/completions` 时，
-    `/v1/chat/completions` 时，先降级转换成 Chat Completions，再进入统一主流程。
+    先降级转换成 Chat Completions，再进入统一主流程。
     """
     message_count = len(payload.get('messages', []))
 
@@ -157,548 +101,11 @@ def _normalize_chat_payload(payload: dict[str, Any]) -> tuple[dict[str, Any], in
     return payload, message_count
 
 
-def _handle_openai_backend(ctx: RouteContext, payload: dict[str, Any], turn: dict[str, Any]):
+def _try_cache_thinking(response_data: dict[str, Any]) -> None:
-    """处理走 OpenAI 兼容后端的聊天补全请求。"""
+    """尝试从非流式响应中缓存思维链内容。"""
-    _dbg(
+    if not isinstance(response_data, dict):
-        '原始请求字段=' + str(list(payload.keys())) + ' '
+        return
-        + '附加字段='
+    for choice in response_data.get('choices', []):
-        + json.dumps(
-            {k: v for k, v in payload.items() if k != 'messages'},
-            ensure_ascii=False,
-            default=str,
-        )[:500]
-    )
-
-    payload = normalize_request(payload, ctx.upstream_model)
-    payload = inject_instructions_cc(payload, ctx.custom_instructions, ctx.instructions_position)
-    _dbg(
-        f'标准化完成：模型={payload.get("model")} '
-        f'工具数={len(payload.get("tools", []))}'
-    )
-
-    url, headers = build_openai_target(ctx)
-    payload = apply_body_modifications(payload, ctx.body_modifications)
-    headers = apply_header_modifications(headers, ctx.header_modifications)
-
-    if ctx.is_stream:
-        return _handle_openai_stream(ctx, payload, url, headers, turn)
-    return _handle_openai_non_stream(ctx, payload, url, headers, turn)
-
-
-def _handle_openai_non_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any],
-):
-    """处理 OpenAI 兼容后端的非流式返回。"""
-    payload['stream'] = False
-    attach_upstream_request(turn, payload, headers)
-    resp, err = forward_request(url, headers, payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    raw = resp.json()
-    attach_upstream_response(turn, raw)
-    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
-
-    data = fix_response(raw)
-    return _finalize_chat_response(ctx, data, turn=turn, debug_label='修复后响应')
-
-
-def _handle_openai_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any],
-):
-    """处理 OpenAI 兼容后端的流式返回。"""
-    payload['stream'] = True
-
-    def generate():
-        """消费上游 OpenAI SSE，并逐段产出给 Cursor 的聊天补全流。"""
-        attach_upstream_request(turn, payload, headers)
-        resp, err = forward_request(url, headers, payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield chat_error_chunk(str(err))
-            return
-
-        think_extractor = ThinkTagExtractor()
-        chunk_count = 0
-        last_usage = None
-        client_chunks: list[dict[str, Any]] = []
-
-        for chunk in iter_openai_sse(resp):
-            if chunk is None:
-                _dbg(f'流式响应结束，共 {chunk_count} 个数据片段')
-                close_chunk = think_extractor.finalize()
-                if close_chunk:
-                    client_chunks.append(close_chunk)
-                    append_client_event(turn, {'type': 'chat_chunk', 'data': close_chunk})
-                    yield sse_data_message(close_chunk)
-                append_client_event(turn, {'type': 'done'})
-                yield sse_data_message('[DONE]')
-                usage_tracker.record(ctx.client_model, last_usage)
-                set_stream_summary(turn, {
-                    'chunk_count': chunk_count,
-                    'client_chunk_count': len(client_chunks),
-                    'usage': last_usage,
-                })
-                attach_client_response(turn, {
-                    'type': 'chat.completion.stream.summary',
-                    'model': ctx.client_model,
-                    'chunk_count': len(client_chunks),
-                    'usage': last_usage,
-                })
-                finalize_turn(turn, usage=last_usage)
-                return
-
-            append_upstream_event(turn, {'type': 'openai_chunk', 'data': chunk})
-            if chunk.get('usage'):
-                last_usage = chunk['usage']
-
-            if chunk_count < 10:
-                _dbg(
-                    f'上游原始片段#{chunk_count}='
-                    + json.dumps(chunk, ensure_ascii=False, default=str)[:500]
-                )
-
-            chunk = fix_stream_chunk(chunk)
-            chunk['model'] = ctx.client_model
-
-            for out in think_extractor.process_chunk(chunk):
-                client_chunks.append(out)
-                append_client_event(turn, {'type': 'chat_chunk', 'data': out})
-                if chunk_count < 10:
-                    _dbg(
-                        f'返回片段#{chunk_count}='
-                        + json.dumps(out, ensure_ascii=False, default=str)[:500]
-                    )
-                yield sse_data_message(out)
-
-            chunk_count += 1
-
-        usage_tracker.record(ctx.client_model, last_usage)
-        set_stream_summary(turn, {
-            'chunk_count': chunk_count,
-            'client_chunk_count': len(client_chunks),
-            'usage': last_usage,
-            'ended_without_done': True,
-        })
-        attach_client_response(turn, {
-            'type': 'chat.completion.stream.summary',
-            'model': ctx.client_model,
-            'chunk_count': len(client_chunks),
-            'usage': last_usage,
-        })
-        finalize_turn(turn, usage=last_usage)
-
-    return sse_response(generate())
-
-
-def _handle_responses_backend(ctx: RouteContext, payload: dict[str, Any], turn: dict[str, Any] | None):
-    """处理走原生 Responses 后端的聊天补全请求。
-
-    当上游只支持 `/v1/responses` 时，需要先把聊天补全请求转换为 Responses 请求，
-    返回时再转换回聊天补全协议。
-    """
-    responses_payload = cc_to_responses_request(payload)
-    responses_payload['model'] = ctx.upstream_model
-    responses_payload = inject_instructions_responses(responses_payload, ctx.custom_instructions, ctx.instructions_position)
-    _dbg(
-        '已转换为 Responses 请求：字段=' + str(list(responses_payload.keys()))
-        + f' 输入项数={len(responses_payload.get("input", []))}'
-    )
-
-    url, headers = build_responses_target(ctx)
-    responses_payload = apply_body_modifications(responses_payload, ctx.body_modifications)
-    headers = apply_header_modifications(headers, ctx.header_modifications)
-
-    if ctx.is_stream:
-        return _handle_responses_stream(ctx, responses_payload, url, headers, turn)
-    return _handle_responses_non_stream(ctx, responses_payload, url, headers, turn)
-
-
-def _handle_responses_non_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理原生 Responses 后端的非流式返回。"""
-    payload['stream'] = False
-    attach_upstream_request(turn, payload, headers)
-    resp, err = forward_request(url, headers, payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    raw = resp.json()
-    attach_upstream_response(turn, raw)
-    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
-
-    data = responses_to_cc_response(raw, ctx.client_model)
-    return _finalize_chat_response(ctx, data, turn=turn, debug_label='Responses 转回聊天补全后')
-
-
-def _handle_responses_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理原生 Responses 后端的流式返回。"""
-    payload['stream'] = True
-    converter = ResponsesToCCStreamConverter(model=ctx.client_model)
-
-    def generate():
-        """消费上游 Responses 事件，并实时转换成聊天补全 chunk。"""
-        attach_upstream_request(turn, payload, headers)
-        resp, err = forward_request(url, headers, payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield chat_error_chunk(str(err))
-            return
-
-        event_count = 0
-        client_chunks: list[Any] = []
-        last_usage: dict[str, Any] | None = None
-        for event_type, event_data in iter_responses_sse(resp):
-            append_upstream_event(turn, {'type': event_type, 'data': event_data})
-            extracted_usage = _extract_responses_usage(event_data)
-            if extracted_usage:
-                last_usage = {
-                    'prompt_tokens': extracted_usage.get('input_tokens', 0),
-                    'completion_tokens': extracted_usage.get('output_tokens', 0),
-                    'total_tokens': extracted_usage.get('total_tokens', 0),
-                }
-            if event_count < 10:
-                _dbg(
-                    f'上游事件#{event_count} 类型={event_type} 数据='
-                    + json.dumps(event_data, ensure_ascii=False, default=str)[:500]
-                )
-
-            for chunk in converter.process_event(event_type, event_data):
-                client_chunks.append(chunk)
-                append_client_event(turn, {'type': 'chat_chunk', 'data': chunk})
-                if isinstance(chunk, dict) and isinstance(chunk.get('usage'), dict):
-                    last_usage = chunk['usage']
-                if event_count < 10:
-                    _dbg(
-                        f'返回片段#{event_count}='
-                        + json.dumps(chunk, ensure_ascii=False, default=str)[:500]
-                    )
-                yield sse_data_message(chunk)
-
-            event_count += 1
-
-        _dbg(f'流式响应结束，共 {event_count} 个事件')
-        append_client_event(turn, {'type': 'done'})
-        yield sse_data_message('[DONE]')
-        usage_tracker.record(ctx.client_model, last_usage)
-        set_stream_summary(turn, {
-            'event_count': event_count,
-            'client_chunk_count': len(client_chunks),
-            'usage': last_usage,
-        })
-        attach_client_response(turn, {
-            'type': 'chat.completion.stream.summary',
-            'model': ctx.client_model,
-            'chunk_count': len(client_chunks),
-            'usage': last_usage,
-        })
-        finalize_turn(turn, usage=last_usage)
-
-    return sse_response(generate())
-
-
-def _handle_gemini_backend(ctx: RouteContext, payload: dict[str, Any], turn: dict[str, Any] | None):
-    """处理走 Gemini Contents 后端的聊天补全请求。"""
-    payload = inject_instructions_cc(payload, ctx.custom_instructions, ctx.instructions_position)
-    gemini_payload = cc_to_gemini_request(payload)
-    _dbg(
-        '已转换为 Gemini 请求：字段=' + str(list(gemini_payload.keys()))
-        + f' 内容数={len(gemini_payload.get("contents", []))}'
-    )
-
-    url, headers = build_gemini_target(ctx, stream=ctx.is_stream)
-    gemini_payload = apply_body_modifications(gemini_payload, ctx.body_modifications)
-    headers = apply_header_modifications(headers, ctx.header_modifications)
-
-    if ctx.is_stream:
-        return _handle_gemini_stream(ctx, gemini_payload, url, headers, turn)
-    return _handle_gemini_non_stream(ctx, gemini_payload, url, headers, turn)
-
-
-def _handle_gemini_non_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Gemini 后端的非流式返回。"""
-    attach_upstream_request(turn, payload, headers)
-    resp, err = forward_request(url, headers, payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    raw = resp.json()
-    attach_upstream_response(turn, raw)
-    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
-
-    data = gemini_to_cc_response(raw)
-    return _finalize_chat_response(ctx, data, turn=turn, debug_label='Gemini 转回聊天补全后')
-
-
-def _handle_gemini_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Gemini 后端的流式返回。"""
-    converter = GeminiStreamConverter()
-
-    def generate():
-        attach_upstream_request(turn, payload, headers)
-        resp, err = forward_request(url, headers, payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield chat_error_chunk(str(err))
-            return
-
-        chunk_count = 0
-        client_chunks: list[Any] = []
-        last_usage: dict[str, Any] | None = None
-        for gemini_chunk in iter_gemini_sse(resp):
-            append_upstream_event(turn, {'type': 'gemini_chunk', 'data': gemini_chunk})
-            usage_meta = gemini_chunk.get('usageMetadata') if isinstance(gemini_chunk, dict) else None
-            if isinstance(usage_meta, dict):
-                last_usage = {
-                    'prompt_tokens': usage_meta.get('promptTokenCount', 0),
-                    'completion_tokens': usage_meta.get('candidatesTokenCount', 0),
-                    'total_tokens': usage_meta.get('totalTokenCount', 0),
-                }
-            if chunk_count < 10:
-                _dbg(
-                    f'上游 Gemini 片段#{chunk_count}='
-                    + json.dumps(gemini_chunk, ensure_ascii=False, default=str)[:500]
-                )
-
-            for cc_chunk in converter.process_chunk(gemini_chunk):
-                cc_chunk['model'] = ctx.client_model
-                client_chunks.append(cc_chunk)
-                append_client_event(turn, {'type': 'chat_chunk', 'data': cc_chunk})
-                if isinstance(cc_chunk, dict) and isinstance(cc_chunk.get('usage'), dict):
-                    last_usage = cc_chunk['usage']
-                if chunk_count < 10:
-                    _dbg(
-                        f'返回片段#{chunk_count}='
-                        + json.dumps(cc_chunk, ensure_ascii=False, default=str)[:500]
-                    )
-                yield sse_data_message(cc_chunk)
-
-            chunk_count += 1
-
-        _dbg(f'流式响应结束，共 {chunk_count} 个数据片段')
-        append_client_event(turn, {'type': 'done'})
-        yield sse_data_message('[DONE]')
-        usage_tracker.record(ctx.client_model, last_usage)
-        set_stream_summary(turn, {
-            'chunk_count': chunk_count,
-            'client_chunk_count': len(client_chunks),
-            'usage': last_usage,
-        })
-        attach_client_response(turn, {
-            'type': 'chat.completion.stream.summary',
-            'model': ctx.client_model,
-            'chunk_count': len(client_chunks),
-            'usage': last_usage,
-        })
-        finalize_turn(turn, usage=last_usage)
-
-    return sse_response(generate())
-
-
-def _handle_anthropic_backend(ctx: RouteContext, payload: dict[str, Any], turn: dict[str, Any] | None):
-    """处理走 Anthropic Messages 后端的聊天补全请求。"""
-    payload['model'] = ctx.upstream_model
-    anthropic_payload = cc_to_messages_request(payload)
-    anthropic_payload = inject_instructions_anthropic(anthropic_payload, ctx.custom_instructions, ctx.instructions_position)
-    _dbg(
-        '已转换为 Messages 请求：字段=' + str(list(anthropic_payload.keys()))
-        + f' 消息数={len(anthropic_payload.get("messages", []))}'
-    )
-
-    url, headers = build_anthropic_target(ctx)
-    anthropic_payload = apply_body_modifications(anthropic_payload, ctx.body_modifications)
-    headers = apply_header_modifications(headers, ctx.header_modifications)
-
-    if ctx.is_stream:
-        return _handle_anthropic_stream(ctx, anthropic_payload, url, headers, turn)
-    return _handle_anthropic_non_stream(ctx, anthropic_payload, url, headers, turn)
-
-
-def _handle_anthropic_non_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Anthropic 后端的非流式返回。"""
-    payload['stream'] = False
-    attach_upstream_request(turn, payload, headers)
-    resp, err = forward_request(url, headers, payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    raw = resp.json()
-    attach_upstream_response(turn, raw)
-    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
-
-    data = messages_to_cc_response(raw)
-    return _finalize_chat_response(ctx, data, turn=turn, debug_label='Messages 转回聊天补全后')
-
-
-def _handle_anthropic_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Anthropic 后端的流式返回。
-
-    这里仍然保留独立的事件级转换器，而不是先落成完整响应再回放，
-    是为了尽量保持 Cursor 端的流式体验和工具调用时序。
-    """
-    payload['stream'] = True
-    converter = AnthropicStreamConverter()
-
-    def generate():
-        """消费上游 Anthropic 事件流，并逐步映射为聊天补全 SSE。"""
-        attach_upstream_request(turn, payload, headers)
-        resp, err = forward_request(url, headers, payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield chat_error_chunk(str(err))
-            return
-
-        event_count = 0
-        client_chunks: list[Any] = []
-        last_usage: dict[str, Any] | None = None
-        for event_type, event_data in iter_anthropic_sse(resp):
-            append_upstream_event(turn, {'type': event_type, 'data': event_data})
-            if event_type == 'message_start':
-                message_usage = event_data.get('message', {}).get('usage', {})
-                if isinstance(message_usage, dict):
-                    last_usage = {
-                        'prompt_tokens': message_usage.get('input_tokens', 0),
-                        'completion_tokens': 0,
-                        'total_tokens': message_usage.get('input_tokens', 0),
-                    }
-            elif event_type == 'message_delta':
-                delta_usage = event_data.get('usage', {})
-                if isinstance(delta_usage, dict):
-                    prompt_tokens = 0
-                    if isinstance(last_usage, dict):
-                        prompt_tokens = last_usage.get('prompt_tokens', 0)
-                    completion_tokens = delta_usage.get('output_tokens', 0)
-                    last_usage = {
-                        'prompt_tokens': prompt_tokens,
-                        'completion_tokens': completion_tokens,
-                        'total_tokens': prompt_tokens + completion_tokens,
-                    }
-            if event_count < 10:
-                _dbg(
-                    f'上游事件#{event_count} 类型={event_type} 数据='
-                    + json.dumps(event_data, ensure_ascii=False, default=str)[:500]
-                )
-
-            for chunk_str in converter.process_event(event_type, event_data):
-                try:
-                    chunk_obj = json.loads(chunk_str)
-                    chunk_obj['model'] = ctx.client_model
-                    if isinstance(chunk_obj.get('usage'), dict):
-                        last_usage = chunk_obj['usage']
-                    chunk_str = json.dumps(chunk_obj, ensure_ascii=False)
-                except (json.JSONDecodeError, TypeError):
-                    pass
-
-                client_chunks.append(chunk_str)
-                append_client_event(turn, {'type': 'chat_chunk', 'data': chunk_str})
-                if event_count < 10:
-                    _dbg(f'返回片段#{event_count}={chunk_str[:500]}')
-                yield sse_data_message(chunk_str)
-
-            event_count += 1
-
-        _dbg(f'流式响应结束，共 {event_count} 个事件')
-        append_client_event(turn, {'type': 'done'})
-        yield sse_data_message('[DONE]')
-        usage_tracker.record(ctx.client_model, last_usage)
-        set_stream_summary(turn, {
-            'event_count': event_count,
-            'client_chunk_count': len(client_chunks),
-            'usage': last_usage,
-        })
-        attach_client_response(turn, {
-            'type': 'chat.completion.stream.summary',
-            'model': ctx.client_model,
-            'chunk_count': len(client_chunks),
-            'usage': last_usage,
-        })
-        finalize_turn(turn, usage=last_usage)
-
-    return sse_response(generate())
-
-
-def _finalize_chat_response(
-    ctx: RouteContext,
-    data: dict[str, Any],
-    *,
-    turn: dict[str, Any] | None,
-    debug_label: str,
-):
-    """统一收尾非流式聊天补全响应。
-
-    三条后端链路最终都会回到 Chat Completions 格式，因此这里集中做：
-    - 回填给 Cursor 展示的模型名
-    - 输出统一调试日志
-    - 输出统一令牌统计日志
-    """
-    data['model'] = ctx.client_model
-    _dbg(debug_label + '=' + json.dumps(data, ensure_ascii=False, default=str)[:1000])
-    log_usage('聊天补全', data.get('usage', {}), input_key='prompt_tokens', output_key='completion_tokens')
-
-    usage_tracker.record(ctx.client_model, data.get('usage'))
-    attach_client_response(turn, data)
-    finalize_turn(turn, usage=data.get('usage'))
-
-    for choice in data.get('choices', []):
         msg = choice.get('message', {})
         if msg.get('reasoning_content'):
             thinking_cache.store_from_response(
@@ -707,8 +114,6 @@ def _finalize_chat_response(
             )
             break
 
-    return jsonify(data)
-
 
 def _log_messages(payload: dict[str, Any]) -> None:
     """记录消息摘要，方便排查请求形态是否符合预期。"""

routes/common.py

@@ -12,7 +12,6 @@ import logging
 from typing import Any
 
 import settings
-from utils.http import build_anthropic_headers, build_gemini_headers, build_openai_headers
 
 logger = logging.getLogger(__name__)
 
@@ -55,42 +54,6 @@ def build_route_context(client_model: str, is_stream: bool) -> RouteContext:
     )
 
 
-def build_openai_target(ctx: RouteContext) -> tuple[str, dict[str, str]]:
-    """根据路由上下文生成 OpenAI 兼容后端的地址和请求头。"""
-    url = f'{ctx.target_url.rstrip("/")}/v1/chat/completions'
-    headers = build_openai_headers(ctx.api_key)
-    return url, headers
-
-
-def build_responses_target(ctx: RouteContext) -> tuple[str, dict[str, str]]:
-    """根据路由上下文生成 OpenAI Responses 后端的地址和请求头。"""
-    url = f'{ctx.target_url.rstrip("/")}/v1/responses'
-    headers = build_openai_headers(ctx.api_key)
-    return url, headers
-
-
-def build_anthropic_target(ctx: RouteContext) -> tuple[str, dict[str, str]]:
-    """根据路由上下文生成 Anthropic 后端的地址和请求头。"""
-    url = f'{ctx.target_url.rstrip("/")}/v1/messages'
-    headers = build_anthropic_headers(ctx.api_key)
-    return url, headers
-
-
-def build_gemini_target(ctx: RouteContext, stream: bool = False) -> tuple[str, dict[str, str]]:
-    """根据路由上下文生成 Gemini 后端的地址和请求头。
-
-    Gemini URL 格式: {base}/v1/models/{model}:generateContent
-    流式: {base}/v1/models/{model}:streamGenerateContent?alt=sse
-    """
-    base = ctx.target_url.rstrip('/')
-    model = ctx.upstream_model
-    if stream:
-        url = f'{base}/v1/models/{model}:streamGenerateContent?alt=sse'
-    else:
-        url = f'{base}/v1/models/{model}:generateContent'
-    headers = build_gemini_headers(ctx.api_key)
-    return url, headers
-
 
 def log_route_context(route_name: str, ctx: RouteContext, *, extra: str = '') -> None:
     """统一输出路由级日志，避免不同入口的日志格式逐渐漂移。"""
@@ -137,11 +100,6 @@ def sse_event_message(event_type: str, data: Any) -> str:
     return f'event: {event_type}\ndata: {payload}\n\n'
 
 
-def chat_error_chunk(message: str, error_type: str = 'upstream_error') -> str:
-    """构造聊天补全流式接口使用的错误消息。"""
-    return sse_data_message({'error': {'message': message, 'type': error_type}})
-
-
 def responses_error_event(message: str) -> str:
     """构造 Responses 流式接口使用的错误事件。"""
     return sse_event_message('error', {'error': message})
@@ -248,3 +206,140 @@ def apply_header_modifications(headers: dict[str, str], modifications: dict[str,
             headers[key] = str(value)
     logger.info('已应用 header_modifications: %s', list(modifications.keys()))
     return headers
+
+
+# ═══════════════════════════════════════════════════════════
+#  后端注册表 + ClientFormatter 实现
+# ═══════════════════════════════════════════════════════════
+
+
+def get_outbound(backend: str):
+    """根据后端类型获取对应的 OutboundTransformer 实例。"""
+    from adapters.cc_anthropic_adapter import AnthropicOutbound
+    from adapters.cc_gemini_adapter import GeminiOutbound
+    from adapters.openai_compat_fixer import OpenAIChatOutbound
+    from adapters.responses_cc_adapter import ResponsesOutbound
+
+    registry = {
+        'openai': OpenAIChatOutbound,
+        'anthropic': AnthropicOutbound,
+        'gemini': GeminiOutbound,
+        'responses': ResponsesOutbound,
+    }
+    cls = registry.get(backend, OpenAIChatOutbound)
+    return cls()
+
+
+class CCClientFormatter:
+    """Chat Completions 客户端格式化器。
+
+    将通用处理结果格式化为 OpenAI Chat Completions 格式，
+    供 /v1/chat/completions 端点使用。
+    """
+
+    def format_response(self, cc_response: dict[str, Any], model: str) -> dict[str, Any]:
+        cc_response['model'] = model
+        return cc_response
+
+    def wrap_stream_item(self, item: Any) -> str:
+        payload = item if isinstance(item, str) else json.dumps(item, ensure_ascii=False)
+        return f'data: {payload}\n\n'
+
+    def format_error(self, message: str) -> str:
+        return sse_data_message({'error': {'message': message, 'type': 'upstream_error'}})
+
+    def format_done(self) -> str | None:
+        return sse_data_message('[DONE]')
+
+    def start_events(self) -> list[str]:
+        return []
+
+    @property
+    def usage_input_key(self) -> str:
+        return 'prompt_tokens'
+
+    @property
+    def usage_output_key(self) -> str:
+        return 'completion_tokens'
+
+
+class ResponsesClientFormatter:
+    """Responses API 客户端格式化器。
+
+    将通用处理结果格式化为 OpenAI Responses 格式，
+    供 /v1/responses 端点使用。
+
+    流式场景使用 ResponsesStreamConverter 做 CC chunk → Responses SSE 转换。
+    """
+
+    def __init__(self, model: str = ''):
+        from adapters.responses_cc_adapter import ResponsesStreamConverter, cc_to_responses
+        self._model = model
+        self._converter = ResponsesStreamConverter(model=model)
+        self._cc_to_responses = cc_to_responses
+
+    def format_response(self, cc_response: dict[str, Any], model: str) -> dict[str, Any]:
+        return self._cc_to_responses(cc_response, model)
+
+    def wrap_stream_item(self, item: Any) -> str:
+        if isinstance(item, str):
+            return item
+        events = self._converter.process_cc_chunk(item)
+        return ''.join(events)
+
+    def format_error(self, message: str) -> str:
+        return responses_error_event(message)
+
+    def format_done(self) -> str | None:
+        events = self._converter.finalize()
+        return ''.join(events) if events else None
+
+    def start_events(self) -> list[str]:
+        return self._converter.start_events()
+
+    @property
+    def usage_input_key(self) -> str:
+        return 'input_tokens'
+
+    @property
+    def usage_output_key(self) -> str:
+        return 'output_tokens'
+
+
+class ResponsesPassthroughFormatter:
+    """Responses 透传格式化器。
+
+    当后端本身就是 Responses 格式时使用，做轻量模型名改写。
+    """
+
+    def __init__(self, model: str = ''):
+        self._model = model
+
+    def format_response(self, response_data: dict[str, Any], model: str) -> dict[str, Any]:
+        response_data['model'] = model
+        return response_data
+
+    def wrap_stream_item(self, item: Any) -> str:
+        if isinstance(item, str):
+            return item
+        event_type = item.pop('_sse_event_type', None)
+        if event_type:
+            return f'event: {event_type}\ndata: {json.dumps(item, ensure_ascii=False)}\n\n'
+        return f'data: {json.dumps(item, ensure_ascii=False)}\n\n'
+
+    def format_error(self, message: str) -> str:
+        return responses_error_event(message)
+
+    def format_done(self) -> str | None:
+        return None
+
+    def start_events(self) -> list[str]:
+        return []
+
+    @property
+    def usage_input_key(self) -> str:
+        return 'input_tokens'
+
+    @property
+    def usage_output_key(self) -> str:
+        return 'output_tokens'

routes/responses.py

@@ -1,7 +1,7 @@
 """路由: /v1/responses
 
 处理 Cursor 对 GPT、Claude-Opus 等模型发出的 Responses API 请求。
-请求会先转换为 Chat Completions 中间表示，再按后端类型分发，最后转换回 Responses 格式。
+请求先转换为 Chat Completions 中间表示，再通过统一出站转换器分发。
 """
 
 from __future__ import annotations
@@ -13,62 +13,30 @@ from typing import Any
 import settings
 from flask import Blueprint, jsonify, request
 
-from adapters.cc_anthropic_adapter import cc_to_messages_request, messages_to_cc_response
+from adapters.openai_compat_fixer import normalize_request
-from adapters.cc_gemini_adapter import GeminiStreamConverter, cc_to_gemini_request, gemini_to_cc_response
+from adapters.responses_cc_adapter import (
-from adapters.openai_compat_fixer import fix_response, fix_stream_chunk, normalize_request
+    AnthropicOutboundForResponses,
-from adapters.responses_cc_adapter import ResponsesStreamConverter, cc_to_responses, responses_to_cc
+    ResponsesNativeOutbound,
-from config import Config
+    responses_to_cc,
+)
+from adapters.unified import handle_non_stream, handle_stream
 from routes.common import (
-    RouteContext,
+    ResponsesClientFormatter,
-    apply_body_modifications,
+    ResponsesPassthroughFormatter,
-    apply_header_modifications,
-    build_anthropic_target,
-    build_gemini_target,
-    build_openai_target,
-    build_responses_target,
     build_route_context,
-    inject_instructions_anthropic,
+    get_outbound,
     inject_instructions_cc,
     inject_instructions_responses,
     log_route_context,
-    log_usage,
-    responses_error_event,
 )
-from utils.http import (
+from utils.request_logger import start_turn
-    forward_request,
-    gen_id,
-    iter_anthropic_sse,
-    iter_gemini_sse,
-    iter_openai_sse,
-    iter_responses_sse,
-    sse_response,
-)
-from utils.request_logger import (
-    append_client_event,
-    append_upstream_event,
-    attach_client_response,
-    attach_error,
-    attach_upstream_request,
-    attach_upstream_response,
-    finalize_turn,
-    set_stream_summary,
-    start_turn,
-)
-from utils.think_tag import ThinkTagExtractor
 from utils.thinking_cache import thinking_cache
-from utils.usage_tracker import usage_tracker
 
 logger = logging.getLogger(__name__)
 
 bp = Blueprint('responses', __name__)
 
 
-def _dbg(message: str) -> None:
-    """仅在调试模式下输出详细日志。"""
-    if settings.get_debug_mode() in ('simple', 'verbose'):
-        logger.info('[响应生成调试] %s', message)
-
-
 @bp.route('/v1/responses', methods=['POST'])
 def responses_endpoint():
     """处理 Responses 请求并按模型映射分发。"""
@@ -90,543 +58,42 @@ def responses_endpoint():
     )
     log_route_context('响应生成', ctx)
 
+    if ctx.backend == 'responses':
+        return _handle_native_responses(ctx, payload, turn)
+
     cc_payload = _build_cc_payload(payload, ctx)
 
-    if ctx.backend == 'openai':
+    if ctx.backend == 'anthropic':
-        return _handle_openai_backend(ctx, cc_payload, turn)
+        outbound = AnthropicOutboundForResponses()
-    if ctx.backend == 'responses':
+    else:
-        return _handle_responses_backend(ctx, payload, turn)
+        outbound = get_outbound(ctx.backend)
-    if ctx.backend == 'gemini':
-        return _handle_gemini_backend(ctx, cc_payload, turn)
-    return _handle_anthropic_backend(ctx, cc_payload, turn)
 
-
+    client_fmt = ResponsesClientFormatter(model=ctx.client_model)
-def _build_cc_payload(payload: dict[str, Any], ctx: RouteContext) -> dict[str, Any]:
-    """将 Responses 请求统一降级为 Chat Completions 中间表示。
-
-    这样后续无论走 OpenAI 兼容后端还是 Anthropic 后端，都能复用一套
-    中间协议，避免在路由层同时维护两套完全不同的请求编排逻辑。
-    """
-    cc_payload = responses_to_cc(payload)
-    cc_payload['model'] = ctx.upstream_model
-    cc_payload['messages'] = thinking_cache.inject(cc_payload.get('messages', []))
-    cc_payload = inject_instructions_cc(cc_payload, ctx.custom_instructions, ctx.instructions_position)
-    _dbg(
-        '已转换为聊天补全中间表示：字段=' + str(list(cc_payload.keys()))
-        + f' 消息数={len(cc_payload.get("messages", []))}'
-    )
-    return cc_payload
-
-
-def _handle_openai_backend(ctx: RouteContext, cc_payload: dict[str, Any], turn: dict[str, Any]):
-    """处理走 OpenAI 兼容后端的 Responses 请求。"""
-    cc_payload = normalize_request(cc_payload)
-    _dbg(
-        f'标准化完成：模型={cc_payload.get("model")} '
-        f'工具数={len(cc_payload.get("tools", []))}'
-    )
-
-    url, headers = build_openai_target(ctx)
-    cc_payload = apply_body_modifications(cc_payload, ctx.body_modifications)
-    headers = apply_header_modifications(headers, ctx.header_modifications)
 
     if ctx.is_stream:
-        return _handle_openai_stream(ctx, cc_payload, url, headers, turn)
+        return handle_stream(ctx, outbound, client_fmt, cc_payload, turn)
-    return _handle_openai_non_stream(ctx, cc_payload, url, headers, turn)
+    return handle_non_stream(ctx, outbound, client_fmt, cc_payload, turn)
 
 
-def _handle_openai_non_stream(
+def _handle_native_responses(ctx, payload: dict[str, Any], turn: dict[str, Any]):
-    ctx: RouteContext,
+    """处理走原生 Responses 后端的请求（直接透传）。"""
-    cc_payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any],
-):
-    """处理 OpenAI 兼容后端的非流式 Responses 返回。"""
-    cc_payload['stream'] = False
-    attach_upstream_request(turn, cc_payload, headers)
-    resp, err = forward_request(url, headers, cc_payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    raw = resp.json()
-    attach_upstream_response(turn, raw)
-    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
-
-    fixed = fix_response(raw)
-    response_data = cc_to_responses(fixed, ctx.client_model)
-    return _finalize_responses_response(
-        response_data,
-        client_model=ctx.client_model,
-        turn=turn,
-        debug_label='转换为 Responses 后',
-    )
-
-
-def _handle_openai_stream(
-    ctx: RouteContext,
-    cc_payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 OpenAI 兼容后端的流式 Responses 返回。"""
-    cc_payload['stream'] = True
-    converter = ResponsesStreamConverter(model=ctx.client_model)
-
-    def generate():
-        """消费 OpenAI 聊天补全流，并实时改写为 Responses SSE。"""
-        yield from converter.start_events()
-
-        attach_upstream_request(turn, cc_payload, headers)
-        resp, err = forward_request(url, headers, cc_payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield responses_error_event(str(err))
-            return
-
-        think_extractor = ThinkTagExtractor()
-        chunk_count = 0
-        client_events: list[str] = []
-
-        for chunk in iter_openai_sse(resp):
-            if chunk is None:
-                _dbg(f'流式响应结束，共 {chunk_count} 个数据片段')
-                finalized_events = converter.finalize()
-                for item in finalized_events:
-                    client_events.append(item)
-                    append_client_event(turn, {'type': 'responses_event', 'data': item})
-                    yield item
-                usage_tracker.record(ctx.client_model)
-                set_stream_summary(turn, {
-                    'chunk_count': chunk_count,
-                    'client_event_count': len(client_events),
-                })
-                attach_client_response(turn, {
-                    'type': 'responses.stream.summary',
-                    'model': ctx.client_model,
-                    'event_count': len(client_events),
-                })
-                finalize_turn(turn)
-                return
-
-            append_upstream_event(turn, {'type': 'openai_chunk', 'data': chunk})
-            if chunk_count < 10:
-                _dbg(
-                    f'上游原始片段#{chunk_count}='
-                    + json.dumps(chunk, ensure_ascii=False, default=str)[:500]
-                )
-
-            chunk = fix_stream_chunk(chunk)
-            for out in think_extractor.process_chunk(chunk):
-                for evt in converter.process_cc_chunk(out):
-                    client_events.append(evt)
-                    append_client_event(turn, {'type': 'responses_event', 'data': evt})
-                    if chunk_count < 10:
-                        _dbg(
-                            f'转换后片段#{chunk_count}='
-                            + json.dumps(out, ensure_ascii=False, default=str)[:500]
-                        )
-                    yield evt
-
-            chunk_count += 1
-
-    return sse_response(generate())
-
-
-def _handle_responses_backend(ctx: RouteContext, payload: dict[str, Any], turn: dict[str, Any] | None):
-    """处理走原生 Responses 后端的请求。
-
-    当中转站本身就只支持 `/v1/responses` 时，不需要再绕到聊天补全中间协议，
-    直接转发原生 Responses 请求即可。
-    """
     payload = dict(payload)
     payload['model'] = ctx.upstream_model
     payload = inject_instructions_responses(payload, ctx.custom_instructions, ctx.instructions_position)
-    url, headers = build_responses_target(ctx)
+
-    payload = apply_body_modifications(payload, ctx.body_modifications)
+    outbound = ResponsesNativeOutbound()
-    headers = apply_header_modifications(headers, ctx.header_modifications)
+    client_fmt = ResponsesPassthroughFormatter(model=ctx.client_model)
 
     if ctx.is_stream:
-        return _handle_responses_stream(ctx, payload, url, headers, turn)
+        return handle_stream(ctx, outbound, client_fmt, payload, turn)
-    return _handle_responses_non_stream(ctx, payload, url, headers, turn)
+    return handle_non_stream(ctx, outbound, client_fmt, payload, turn)
 
 
-def _handle_responses_non_stream(
+def _build_cc_payload(payload: dict[str, Any], ctx) -> dict[str, Any]:
-    ctx: RouteContext,
+    """将 Responses 请求统一降级为 Chat Completions 中间表示。"""
-    payload: dict[str, Any],
+    cc_payload = responses_to_cc(payload)
-    url: str,
+    cc_payload['model'] = ctx.upstream_model
-    headers: dict[str, str],
+    cc_payload = normalize_request(cc_payload)
-    turn: dict[str, Any] | None,
+    cc_payload['messages'] = thinking_cache.inject(cc_payload.get('messages', []))
-):
+    cc_payload = inject_instructions_cc(cc_payload, ctx.custom_instructions, ctx.instructions_position)
-    """处理原生 Responses 后端的非流式返回。"""
+    return cc_payload
-    payload['stream'] = False
-    attach_upstream_request(turn, payload, headers)
-    resp, err = forward_request(url, headers, payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    response_data = resp.json()
-    attach_upstream_response(turn, response_data)
-    response_data['model'] = ctx.client_model
-    return _finalize_responses_response(
-        response_data,
-        client_model=ctx.client_model,
-        turn=turn,
-        debug_label='原生 Responses 返回后',
-    )
-
-
-def _handle_responses_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理原生 Responses 后端的流式返回。"""
-    payload['stream'] = True
-    converter = ResponsesStreamConverter(model=ctx.client_model)
-
-    def generate():
-        """透传上游原生 Responses 流，并做轻量模型名改写。"""
-        attach_upstream_request(turn, payload, headers)
-        resp, err = forward_request(url, headers, payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield responses_error_event(str(err))
-            return
-
-        event_count = 0
-        client_events: list[str] = []
-        last_usage: dict[str, Any] | None = None
-        for event_type, event_data in iter_responses_sse(resp):
-            append_upstream_event(turn, {'type': event_type, 'data': event_data})
-            extracted_usage = _extract_responses_usage(event_data)
-            if extracted_usage:
-                last_usage = extracted_usage
-            if event_count < 10:
-                _dbg(
-                    f'上游事件#{event_count} 类型={event_type} 数据='
-                    + json.dumps(event_data, ensure_ascii=False, default=str)[:500]
-                )
-            produced = converter.process_responses_event(event_type, event_data)
-            for evt in produced:
-                client_events.append(evt)
-                append_client_event(turn, {'type': 'responses_event', 'data': evt})
-                yield evt
-            event_count += 1
-
-        _dbg(f'流式响应结束，共 {event_count} 个事件')
-        usage_tracker.record(
-            ctx.client_model,
-            last_usage,
-            input_key='input_tokens',
-            output_key='output_tokens',
-        )
-        set_stream_summary(turn, {
-            'event_count': event_count,
-            'client_event_count': len(client_events),
-            'usage': last_usage,
-        })
-        attach_client_response(turn, {
-            'type': 'responses.stream.summary',
-            'model': ctx.client_model,
-            'event_count': len(client_events),
-            'usage': last_usage,
-        })
-        finalize_turn(turn, usage=last_usage)
-
-    return sse_response(generate())
-
-
-def _extract_responses_usage(event_data: dict[str, Any]) -> dict[str, Any] | None:
-    """从原生 Responses 事件中提取 usage。
-
-    原生 `/v1/responses` 流式通常会在 `response.completed` 事件里携带 usage，
-    也可能直接挂在顶层 `usage` 字段。这里统一做兼容提取，供统计与日志复用。
-    """
-    if not isinstance(event_data, dict):
-        return None
-    usage = event_data.get('usage')
-    if isinstance(usage, dict):
-        return usage
-    response_obj = event_data.get('response')
-    if isinstance(response_obj, dict):
-        nested_usage = response_obj.get('usage')
-        if isinstance(nested_usage, dict):
-            return nested_usage
-    return None
-
-
-def _handle_gemini_backend(ctx: RouteContext, cc_payload: dict[str, Any], turn: dict[str, Any] | None):
-    """处理走 Gemini Contents 后端的 Responses 请求。"""
-    gemini_payload = cc_to_gemini_request(cc_payload)
-    _dbg(
-        '已转换为 Gemini 请求：字段=' + str(list(gemini_payload.keys()))
-        + f' 内容数={len(gemini_payload.get("contents", []))}'
-    )
-
-    url, headers = build_gemini_target(ctx, stream=ctx.is_stream)
-    gemini_payload = apply_body_modifications(gemini_payload, ctx.body_modifications)
-    headers = apply_header_modifications(headers, ctx.header_modifications)
-
-    if ctx.is_stream:
-        return _handle_gemini_stream(ctx, gemini_payload, url, headers, turn)
-    return _handle_gemini_non_stream(ctx, gemini_payload, url, headers, turn)
-
-
-def _handle_gemini_non_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Gemini 后端的非流式 Responses 返回。"""
-    attach_upstream_request(turn, payload, headers)
-    resp, err = forward_request(url, headers, payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    raw = resp.json()
-    attach_upstream_response(turn, raw)
-    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
-
-    cc_data = gemini_to_cc_response(raw)
-    response_data = cc_to_responses(cc_data, ctx.client_model)
-    return _finalize_responses_response(
-        response_data,
-        client_model=ctx.client_model,
-        turn=turn,
-        debug_label='Gemini 转回 Responses 后',
-    )
-
-
-def _handle_gemini_stream(
-    ctx: RouteContext,
-    payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Gemini 后端的流式 Responses 返回。"""
-    converter = ResponsesStreamConverter(model=ctx.client_model)
-    gemini_converter = GeminiStreamConverter()
-
-    def generate():
-        yield from converter.start_events()
-
-        attach_upstream_request(turn, payload, headers)
-        resp, err = forward_request(url, headers, payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield responses_error_event(str(err))
-            return
-
-        chunk_count = 0
-        client_events: list[str] = []
-        last_usage: dict[str, Any] | None = None
-        for gemini_chunk in iter_gemini_sse(resp):
-            append_upstream_event(turn, {'type': 'gemini_chunk', 'data': gemini_chunk})
-            usage_meta = gemini_chunk.get('usageMetadata') if isinstance(gemini_chunk, dict) else None
-            if isinstance(usage_meta, dict):
-                last_usage = {
-                    'input_tokens': usage_meta.get('promptTokenCount', 0),
-                    'output_tokens': usage_meta.get('candidatesTokenCount', 0),
-                    'total_tokens': usage_meta.get('totalTokenCount', 0),
-                }
-            if chunk_count < 10:
-                _dbg(
-                    f'上游 Gemini 片段#{chunk_count}='
-                    + json.dumps(gemini_chunk, ensure_ascii=False, default=str)[:500]
-                )
-
-            for cc_chunk in gemini_converter.process_chunk(gemini_chunk):
-                for evt in converter.process_cc_chunk(cc_chunk):
-                    client_events.append(evt)
-                    append_client_event(turn, {'type': 'responses_event', 'data': evt})
-                    yield evt
-
-            chunk_count += 1
-
-        _dbg(f'流式响应结束，共 {chunk_count} 个数据片段')
-        finalized_events = converter.finalize()
-        for evt in finalized_events:
-            client_events.append(evt)
-            append_client_event(turn, {'type': 'responses_event', 'data': evt})
-            yield evt
-        usage_tracker.record(
-            ctx.client_model,
-            last_usage,
-            input_key='input_tokens',
-            output_key='output_tokens',
-        )
-        set_stream_summary(turn, {
-            'chunk_count': chunk_count,
-            'client_event_count': len(client_events),
-            'usage': last_usage,
-        })
-        attach_client_response(turn, {
-            'type': 'responses.stream.summary',
-            'model': ctx.client_model,
-            'event_count': len(client_events),
-            'usage': last_usage,
-        })
-        finalize_turn(turn, usage=last_usage)
-
-    return sse_response(generate())
-
-
-def _handle_anthropic_backend(ctx: RouteContext, cc_payload: dict[str, Any], turn: dict[str, Any] | None):
-    """处理走 Anthropic 后端的 Responses 请求。"""
-    anthropic_payload = cc_to_messages_request(cc_payload)
-    _dbg(
-        '已转换为 Messages 请求：字段=' + str(list(anthropic_payload.keys()))
-        + f' 消息数={len(anthropic_payload.get("messages", []))}'
-    )
-
-    url, headers = build_anthropic_target(ctx)
-    anthropic_payload = apply_body_modifications(anthropic_payload, ctx.body_modifications)
-    headers = apply_header_modifications(headers, ctx.header_modifications)
-
-    if ctx.is_stream:
-        return _handle_anthropic_stream(ctx, anthropic_payload, url, headers, turn)
-    return _handle_anthropic_non_stream(ctx, anthropic_payload, url, headers, turn)
-
-
-def _handle_anthropic_non_stream(
-    ctx: RouteContext,
-    anthropic_payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Anthropic 后端的非流式 Responses 返回。"""
-    anthropic_payload['stream'] = False
-    attach_upstream_request(turn, anthropic_payload, headers)
-    resp, err = forward_request(url, headers, anthropic_payload)
-    if err:
-        attach_error(turn, {'stage': 'forward_request', 'message': 'upstream request failed'})
-        finalize_turn(turn)
-        return err
-
-    raw = resp.json()
-    attach_upstream_response(turn, raw)
-    _dbg('上游原始响应=' + json.dumps(raw, ensure_ascii=False, default=str)[:1000])
-
-    cc_data = messages_to_cc_response(raw)
-    response_data = cc_to_responses(cc_data, ctx.client_model)
-    return _finalize_responses_response(
-        response_data,
-        client_model=ctx.client_model,
-        turn=turn,
-        debug_label='Messages 转回 Responses 后',
-    )
-
-
-def _handle_anthropic_stream(
-    ctx: RouteContext,
-    anthropic_payload: dict[str, Any],
-    url: str,
-    headers: dict[str, str],
-    turn: dict[str, Any] | None,
-):
-    """处理 Anthropic 后端的流式 Responses 返回。
-
-    这里直接将 Anthropic SSE 事件映射到 Responses SSE，故意跳过 CC 流式中间态，
-    这样可以减少一次事件重组，降低流式转换复杂度，也更容易保留原始时序。
-    """
-    anthropic_payload['stream'] = True
-    converter = ResponsesStreamConverter(model=ctx.client_model)
-
-    def generate():
-        """消费 Anthropic SSE，并直接映射为 Responses 事件序列。"""
-        yield from converter.start_events()
-
-        attach_upstream_request(turn, anthropic_payload, headers)
-        resp, err = forward_request(url, headers, anthropic_payload, stream=True)
-        if err:
-            attach_error(turn, {'stage': 'forward_request', 'message': str(err)})
-            set_stream_summary(turn, {'status': 'error'})
-            finalize_turn(turn)
-            yield responses_error_event(str(err))
-            return
-
-        event_count = 0
-        client_events: list[str] = []
-        for event_type, event_data in iter_anthropic_sse(resp):
-            append_upstream_event(turn, {'type': event_type, 'data': event_data})
-            if event_count < 10:
-                _dbg(
-                    f'上游事件#{event_count} 类型={event_type} 数据='
-                    + json.dumps(event_data, ensure_ascii=False, default=str)[:500]
-                )
-
-            produced = converter.process_anthropic_event(event_type, event_data)
-            for evt in produced:
-                client_events.append(evt)
-                append_client_event(turn, {'type': 'responses_event', 'data': evt})
-                yield evt
-            event_count += 1
-
-        _dbg(f'流式响应结束，共 {event_count} 个事件')
-        finalized_events = converter.finalize()
-        for evt in finalized_events:
-            client_events.append(evt)
-            append_client_event(turn, {'type': 'responses_event', 'data': evt})
-            yield evt
-        usage_tracker.record(ctx.client_model)
-        set_stream_summary(turn, {
-            'event_count': event_count,
-            'client_event_count': len(client_events),
-        })
-        attach_client_response(turn, {
-            'type': 'responses.stream.summary',
-            'model': ctx.client_model,
-            'event_count': len(client_events),
-        })
-        finalize_turn(turn)
-
-    return sse_response(generate())
-
-
-def _finalize_responses_response(
-    response_data: dict[str, Any],
-    *,
-    client_model: str,
-    turn: dict[str, Any],
-    debug_label: str,
-):
-    """统一收尾非流式 Responses 响应。
-
-    两条转换链路和一条原生 Responses 链路最终都会回到 Responses 对象，因此这里集中
-    处理调试日志、回填展示模型名以及 usage 日志。
-    """
-    response_data['model'] = response_data.get('model') or ''
-    _dbg(debug_label + '=' + json.dumps(response_data, ensure_ascii=False, default=str)[:1000])
-    log_usage('响应生成', response_data.get('usage', {}), input_key='input_tokens', output_key='output_tokens')
-
-    usage_tracker.record(
-        client_model,
-        response_data.get('usage'),
-        input_key='input_tokens',
-        output_key='output_tokens',
-    )
-
-    attach_client_response(turn, response_data)
-    finalize_turn(turn, usage=response_data.get('usage'))
-
-    return jsonify(response_data)