363 lines
13 KiB
Python
363 lines
13 KiB
Python
"""OpenAI Chat Completions ↔ Gemini Contents 格式转换
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将 CC 格式请求转换为 Gemini generateContent 格式,
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并将 Gemini 响应转换回 CC 格式。仅支持出站方向(CC → Gemini → CC)。
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"""
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from __future__ import annotations
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import json
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import logging
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from typing import Any
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from utils.http import gen_id
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JsonDict = dict[str, Any]
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logger = logging.getLogger(__name__)
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_FINISH_REASON_MAP = {
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'STOP': 'stop',
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'MAX_TOKENS': 'length',
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'SAFETY': 'content_filter',
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'RECITATION': 'content_filter',
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}
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# ═══════════════════════════════════════════════════════════
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# 请求转换: CC → Gemini generateContent
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# ═══════════════════════════════════════════════════════════
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def cc_to_gemini_request(payload: JsonDict) -> JsonDict:
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"""将 CC 请求转换为 Gemini generateContent 请求。"""
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messages = payload.get('messages', [])
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system_parts: list[str] = []
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contents: list[JsonDict] = []
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for msg in messages:
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role = msg.get('role', '')
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if role in ('system', 'developer'):
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system_parts.append(_flatten_text(msg.get('content', '')))
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continue
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converted = _convert_message(msg)
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if converted:
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contents.append(converted)
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contents = _merge_same_role(contents)
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result: JsonDict = {
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'contents': contents,
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'generationConfig': _build_generation_config(payload),
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}
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if system_parts:
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result['systemInstruction'] = {
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'parts': [{'text': '\n\n'.join(system_parts)}],
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}
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tools = _convert_tools(payload.get('tools'))
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if tools:
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result['tools'] = tools
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return result
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# ═══════════════════════════════════════════════════════════
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# 非流式响应转换: Gemini → CC
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# ═══════════════════════════════════════════════════════════
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def gemini_to_cc_response(data: JsonDict, request_id: str | None = None) -> JsonDict:
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"""将 Gemini generateContent 响应转换为 CC 响应。"""
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request_id = request_id or gen_id('chatcmpl-')
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candidates = data.get('candidates', [])
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candidate = candidates[0] if candidates else {}
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content_text, reasoning_text, tool_calls = _extract_parts(
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candidate.get('content', {}).get('parts', [])
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)
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finish = candidate.get('finishReason', 'STOP')
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if tool_calls and finish == 'STOP':
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finish_reason = 'tool_calls'
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else:
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finish_reason = _FINISH_REASON_MAP.get(finish, 'stop')
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message: JsonDict = {'role': 'assistant', 'content': content_text or None}
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if reasoning_text:
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message['reasoning_content'] = reasoning_text
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if tool_calls:
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message['tool_calls'] = tool_calls
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usage = _convert_usage(data.get('usageMetadata', {}))
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return {
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'id': request_id,
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'object': 'chat.completion',
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'model': data.get('modelVersion', 'gemini'),
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'choices': [{'index': 0, 'message': message, 'finish_reason': finish_reason}],
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'usage': usage,
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}
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# ═══════════════════════════════════════════════════════════
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# 流式转换: Gemini SSE → CC chunks
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# ═══════════════════════════════════════════════════════════
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class GeminiStreamConverter:
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"""将 Gemini SSE chunk 逐个转换为 CC chunk。
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Gemini 流式每个 SSE data 是一个完整的 GenerateContentResponse,
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包含 candidates[0].content.parts。
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"""
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def __init__(self, request_id: str | None = None):
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self._id = request_id or gen_id('chatcmpl-')
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self._tool_call_index = 0
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self._started = False
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def process_chunk(self, data: JsonDict) -> list[JsonDict]:
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"""处理一个 Gemini SSE chunk,返回 CC chunk 列表。"""
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results: list[JsonDict] = []
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candidates = data.get('candidates', [])
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if not candidates:
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return results
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candidate = candidates[0]
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parts = candidate.get('content', {}).get('parts', [])
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if not self._started:
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self._started = True
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results.append(self._make_chunk({'role': 'assistant', 'content': ''}))
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for part in parts:
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if part.get('thought') and part.get('text'):
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results.append(self._make_chunk({'reasoning_content': part['text']}))
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elif 'text' in part and not part.get('thought'):
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results.append(self._make_chunk({'content': part['text']}))
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elif 'functionCall' in part:
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fc = part['functionCall']
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results.append(self._make_chunk({'tool_calls': [{
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'index': self._tool_call_index,
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'id': fc.get('id') or gen_id('call_'),
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'type': 'function',
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'function': {
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'name': fc.get('name', ''),
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'arguments': json.dumps(fc.get('args', {}), ensure_ascii=False),
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},
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}]}))
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self._tool_call_index += 1
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finish = candidate.get('finishReason')
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if finish:
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has_tools = self._tool_call_index > 0
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if has_tools and finish == 'STOP':
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fr = 'tool_calls'
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else:
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fr = _FINISH_REASON_MAP.get(finish, 'stop')
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chunk = self._make_chunk({}, finish_reason=fr)
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usage_meta = data.get('usageMetadata')
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if usage_meta:
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chunk['usage'] = _convert_usage(usage_meta)
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results.append(chunk)
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return results
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def _make_chunk(self, delta: JsonDict, finish_reason: str | None = None) -> JsonDict:
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choice: JsonDict = {'index': 0, 'delta': delta}
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if finish_reason:
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choice['finish_reason'] = finish_reason
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return {
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'id': self._id,
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'object': 'chat.completion.chunk',
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'model': 'gemini',
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'choices': [choice],
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}
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# ═══════════════════════════════════════════════════════════
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# 请求转换辅助
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# ═══════════════════════════════════════════════════════════
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def _convert_message(msg: JsonDict) -> JsonDict | None:
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"""将单条 CC 消息转为 Gemini Content。"""
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role = msg.get('role', '')
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gemini_role = 'model' if role == 'assistant' else 'user'
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parts: list[JsonDict] = []
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if role == 'tool':
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return {
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'role': 'user',
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'parts': [{
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'functionResponse': {
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'name': msg.get('name', msg.get('tool_call_id', '')),
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'response': _parse_json_safe(msg.get('content', '')),
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},
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}],
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}
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if msg.get('reasoning_content'):
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parts.append({'text': msg['reasoning_content'], 'thought': True})
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content = msg.get('content')
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if isinstance(content, str) and content:
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parts.append({'text': content})
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elif isinstance(content, list):
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for block in content:
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if not isinstance(block, dict):
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continue
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if block.get('type') == 'text':
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parts.append({'text': block.get('text', '')})
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elif block.get('type') == 'image_url':
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img = _convert_image_part(block)
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if img:
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parts.append(img)
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for tc in msg.get('tool_calls', []):
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func = tc.get('function', {})
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parts.append({
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'functionCall': {
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'name': func.get('name', ''),
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'args': _parse_json_safe(func.get('arguments', '{}')),
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},
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})
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if not parts:
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return None
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return {'role': gemini_role, 'parts': parts}
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def _convert_image_part(block: JsonDict) -> JsonDict | None:
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"""将 OpenAI image_url 转为 Gemini inlineData。"""
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url_data = block.get('image_url', {})
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url = url_data.get('url', '') if isinstance(url_data, dict) else str(url_data)
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if url.startswith('data:'):
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media_type, _, b64 = url.partition(';base64,')
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return {'inlineData': {
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'mimeType': media_type.replace('data:', '') or 'image/png',
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'data': b64,
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}}
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return None
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def _build_generation_config(payload: JsonDict) -> JsonDict:
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"""从 CC payload 构建 Gemini generationConfig。"""
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config: JsonDict = {}
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if 'max_tokens' in payload:
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config['maxOutputTokens'] = payload['max_tokens']
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elif 'max_completion_tokens' in payload:
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config['maxOutputTokens'] = payload['max_completion_tokens']
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if 'temperature' in payload:
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config['temperature'] = payload['temperature']
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if 'top_p' in payload:
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config['topP'] = payload['top_p']
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stop = payload.get('stop')
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if stop:
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config['stopSequences'] = stop if isinstance(stop, list) else [stop]
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return config
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def _convert_tools(tools: Any) -> list[JsonDict] | None:
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"""将 CC tools 转为 Gemini functionDeclarations。"""
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if not isinstance(tools, list) or not tools:
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return None
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declarations: list[JsonDict] = []
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for tool in tools:
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if not isinstance(tool, dict):
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continue
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func = tool.get('function', tool) if tool.get('type') == 'function' else tool
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if 'name' not in func:
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continue
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decl: JsonDict = {
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'name': func.get('name', ''),
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'description': func.get('description', ''),
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}
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params = func.get('parameters')
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if params:
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decl['parameters'] = params
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declarations.append(decl)
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if not declarations:
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return None
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return [{'functionDeclarations': declarations}]
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# ═══════════════════════════════════════════════════════════
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# 响应转换辅助
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# ═══════════════════════════════════════════════════════════
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def _extract_parts(parts: list[Any]) -> tuple[str, str, list[JsonDict]]:
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"""从 Gemini parts 中提取文本、思考内容和工具调用。"""
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text = ''
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reasoning = ''
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tool_calls: list[JsonDict] = []
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for part in parts:
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if not isinstance(part, dict):
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continue
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if part.get('thought') and 'text' in part:
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reasoning += part['text']
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elif 'text' in part:
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text += part['text']
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elif 'functionCall' in part:
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fc = part['functionCall']
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tool_calls.append({
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'index': len(tool_calls),
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'id': fc.get('id') or gen_id('call_'),
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'type': 'function',
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'function': {
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'name': fc.get('name', ''),
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'arguments': json.dumps(fc.get('args', {}), ensure_ascii=False),
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},
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})
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return text, reasoning, tool_calls
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def _convert_usage(meta: JsonDict) -> JsonDict:
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"""将 Gemini usageMetadata 转为 CC usage。"""
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prompt = meta.get('promptTokenCount', 0)
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candidates = meta.get('candidatesTokenCount', 0)
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thoughts = meta.get('thoughtsTokenCount', 0)
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completion = candidates + thoughts
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return {
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'prompt_tokens': prompt,
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'completion_tokens': completion,
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'total_tokens': prompt + completion,
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}
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def _merge_same_role(contents: list[JsonDict]) -> list[JsonDict]:
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"""合并相邻同角色的 Gemini contents。"""
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if not contents:
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return contents
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merged = [contents[0]]
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for c in contents[1:]:
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if c['role'] == merged[-1]['role']:
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merged[-1]['parts'].extend(c['parts'])
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else:
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merged.append(c)
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return merged
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def _flatten_text(content: Any) -> str:
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if isinstance(content, str):
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return content
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if isinstance(content, list):
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return '\n'.join(
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p.get('text', '') if isinstance(p, dict) else str(p)
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for p in content
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)
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return str(content)
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def _parse_json_safe(text: Any) -> Any:
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if not isinstance(text, str):
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return text if text is not None else {}
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try:
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return json.loads(text)
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except (json.JSONDecodeError, ValueError):
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return {'result': text} if text else {}
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