main.py

import asyncio
import json
from datetime import datetime, timezone
import os
import base64
import tempfile

from fastapi import FastAPI, HTTPException, Request, Depends, Header
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from fastapi.responses import StreamingResponse
from pydantic import BaseModel
from typing import List, Optional, Dict, Any, Union
import time
import uuid
import logging

from gemini_webapi import GeminiClient, set_log_level
from gemini_webapi.constants import Model

# Configure logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)
set_log_level("INFO")

app = FastAPI(title="Gemini API FastAPI Server")

# Add CORS middleware
app.add_middleware(
	CORSMiddleware,
	allow_origins=["*"],
	allow_credentials=True,
	allow_methods=["*"],
	allow_headers=["*"],
)

# Global client
gemini_client = None

# Authentication credentials
SECURE_1PSID = os.environ.get("SECURE_1PSID", "")
SECURE_1PSIDTS = os.environ.get("SECURE_1PSIDTS", "")
API_KEY = os.environ.get("API_KEY", "")

# Print debug info at startup
if not SECURE_1PSID or not SECURE_1PSIDTS:
	logger.warning("⚠️ Gemini API credentials are not set or empty! Please check your environment variables.")
	logger.warning("Make sure SECURE_1PSID and SECURE_1PSIDTS are correctly set in your .env file or environment.")
	logger.warning("If using Docker, ensure the .env file is correctly mounted and formatted.")
	logger.warning("Example format in .env file (no quotes):")
	logger.warning("SECURE_1PSID=your_secure_1psid_value_here")
	logger.warning("SECURE_1PSIDTS=your_secure_1psidts_value_here")
else:
	# Only log the first few characters for security
	logger.info(f"Credentials found. SECURE_1PSID starts with: {SECURE_1PSID[:5]}...")
	logger.info(f"Credentials found. SECURE_1PSIDTS starts with: {SECURE_1PSIDTS[:5]}...")

if not API_KEY:
	logger.warning("⚠️ API_KEY is not set or empty! API authentication will not work.")
	logger.warning("Make sure API_KEY is correctly set in your .env file or environment.")
else:
	logger.info(f"API_KEY found. API_KEY starts with: {API_KEY[:5]}...")


# Pydantic models for API requests and responses
class ContentItem(BaseModel):
	type: str
	text: Optional[str] = None
	image_url: Optional[Dict[str, str]] = None


class Message(BaseModel):
	role: str
	content: Union[str, List[ContentItem]]
	name: Optional[str] = None


class ChatCompletionRequest(BaseModel):
	model: str
	messages: List[Message]
	temperature: Optional[float] = 0.7
	top_p: Optional[float] = 1.0
	n: Optional[int] = 1
	stream: Optional[bool] = False
	max_tokens: Optional[int] = None
	presence_penalty: Optional[float] = 0
	frequency_penalty: Optional[float] = 0
	user: Optional[str] = None


class Choice(BaseModel):
	index: int
	message: Message
	finish_reason: str


class Usage(BaseModel):
	prompt_tokens: int
	completion_tokens: int
	total_tokens: int


class ChatCompletionResponse(BaseModel):
	id: str
	object: str = "chat.completion"
	created: int
	model: str
	choices: List[Choice]
	usage: Usage


class ModelData(BaseModel):
	id: str
	object: str = "model"
	created: int
	owned_by: str = "google"


class ModelList(BaseModel):
	object: str = "list"
	data: List[ModelData]


# Authentication dependency
async def verify_api_key(authorization: str = Header(None)):
	if not API_KEY:
		# If API_KEY is not set in environment, skip validation (for development)
		logger.warning("API key validation skipped - no API_KEY set in environment")
		return

	if not authorization:
		raise HTTPException(status_code=401, detail="Missing Authorization header")
	
	try:
		scheme, token = authorization.split()
		if scheme.lower() != "bearer":
			raise HTTPException(status_code=401, detail="Invalid authentication scheme. Use Bearer token")
		
		if token != API_KEY:
			raise HTTPException(status_code=401, detail="Invalid API key")
	except ValueError:
		raise HTTPException(status_code=401, detail="Invalid authorization format. Use 'Bearer YOUR_API_KEY'")
	
	return token


# Simple error handler middleware
@app.middleware("http")
async def error_handling(request: Request, call_next):
	try:
		return await call_next(request)
	except Exception as e:
		logger.error(f"Request failed: {str(e)}")
		return JSONResponse(status_code=500, content={"error": {"message": str(e), "type": "internal_server_error"}})


# Get list of available models
@app.get("/v1/models")
async def list_models():
	"""返回 gemini_webapi 中声明的模型列表"""
	now = int(datetime.now(tz=timezone.utc).timestamp())
	data = [
		{
			"id": m.model_name,  # 如 "gemini-2.0-flash"
			"object": "model",
			"created": now,
			"owned_by": "google-gemini-web",
		}
		for m in Model
	]
	print(data)
	return {"object": "list", "data": data}


# Helper to convert between Gemini and OpenAI model names
def map_model_name(openai_model_name: str) -> Model:
	"""根据模型名称字符串查找匹配的 Model 枚举值"""
	# 打印所有可用模型以便调试
	all_models = [m.model_name if hasattr(m, "model_name") else str(m) for m in Model]
	logger.info(f"Available models: {all_models}")

	# 首先尝试直接查找匹配的模型名称
	for m in Model:
		model_name = m.model_name if hasattr(m, "model_name") else str(m)
		if openai_model_name.lower() in model_name.lower():
			return m

	# 如果找不到匹配项，使用默认映射
	model_keywords = {
		"gemini-pro": ["pro", "2.0"],
		"gemini-pro-vision": ["vision", "pro"],
		"gemini-flash": ["flash", "2.0"],
		"gemini-1.5-pro": ["1.5", "pro"],
		"gemini-1.5-flash": ["1.5", "flash"],
	}

	# 根据关键词匹配
	keywords = model_keywords.get(openai_model_name, ["pro"])  # 默认使用pro模型

	for m in Model:
		model_name = m.model_name if hasattr(m, "model_name") else str(m)
		if all(kw.lower() in model_name.lower() for kw in keywords):
			return m

	# 如果还是找不到，返回第一个模型
	return next(iter(Model))


# Prepare conversation history from OpenAI messages format
def prepare_conversation(messages: List[Message]) -> tuple:
	conversation = ""
	temp_files = []

	for msg in messages:
		if isinstance(msg.content, str):
			# String content handling
			if msg.role == "system":
				conversation += f"System: {msg.content}\n\n"
			elif msg.role == "user":
				conversation += f"Human: {msg.content}\n\n"
			elif msg.role == "assistant":
				conversation += f"Assistant: {msg.content}\n\n"
		else:
			# Mixed content handling
			if msg.role == "user":
				conversation += "Human: "
			elif msg.role == "system":
				conversation += "System: "
			elif msg.role == "assistant":
				conversation += "Assistant: "

			for item in msg.content:
				if item.type == "text":
					conversation += item.text or ""
				elif item.type == "image_url" and item.image_url:
					# Handle image
					image_url = item.image_url.get("url", "")
					if image_url.startswith("data:image/"):
						# Process base64 encoded image
						try:
							# Extract the base64 part
							base64_data = image_url.split(",")[1]
							image_data = base64.b64decode(base64_data)

							# Create temporary file to hold the image
							with tempfile.NamedTemporaryFile(delete=False, suffix=".png") as tmp:
								tmp.write(image_data)
								temp_files.append(tmp.name)
						except Exception as e:
							logger.error(f"Error processing base64 image: {str(e)}")

			conversation += "\n\n"

	# Add a final prompt for the assistant to respond to
	conversation += "Assistant: "

	return conversation, temp_files


# Dependency to get the initialized Gemini client
async def get_gemini_client():
	global gemini_client
	if gemini_client is None:
		try:
			gemini_client = GeminiClient(SECURE_1PSID, SECURE_1PSIDTS)
			await gemini_client.init(timeout=300)
		except Exception as e:
			logger.error(f"Failed to initialize Gemini client: {str(e)}")
			raise HTTPException(status_code=500, detail=f"Failed to initialize Gemini client: {str(e)}")
	return gemini_client


@app.post("/v1/chat/completions")
async def create_chat_completion(request: ChatCompletionRequest, api_key: str = Depends(verify_api_key)):
	try:
		# 确保客户端已初始化
		global gemini_client
		if gemini_client is None:
			gemini_client = GeminiClient(SECURE_1PSID, SECURE_1PSIDTS)
			await gemini_client.init(timeout=300)
			logger.info("Gemini client initialized successfully")

		# 转换消息为对话格式
		conversation, temp_files = prepare_conversation(request.messages)
		logger.info(f"Prepared conversation: {conversation}")
		logger.info(f"Temp files: {temp_files}")

		# 获取适当的模型
		model = map_model_name(request.model)
		logger.info(f"Using model: {model}")

		# 生成响应
		logger.info("Sending request to Gemini...")
		if temp_files:
			# With files
			response = await gemini_client.generate_content(conversation, files=temp_files, model=model)
		else:
			# Text only
			response = await gemini_client.generate_content(conversation, model=model)

		# 清理临时文件
		for temp_file in temp_files:
			try:
				os.unlink(temp_file)
			except Exception as e:
				logger.warning(f"Failed to delete temp file {temp_file}: {str(e)}")

		# 提取文本响应
		reply_text = ""
		if hasattr(response, "text"):
			reply_text = response.text
		else:
			reply_text = str(response)

		logger.info(f"Response: {reply_text}")

		if not reply_text or reply_text.strip() == "":
			logger.warning("Empty response received from Gemini")
			reply_text = "服务器返回了空响应。请检查 Gemini API 凭据是否有效。"

		# 创建响应对象
		completion_id = f"chatcmpl-{uuid.uuid4()}"
		created_time = int(time.time())

		# 检查客户端是否请求流式响应
		if request.stream:
			# 实现流式响应
			async def generate_stream():
				# 创建 SSE 格式的流式响应
				# 先发送开始事件
				data = {
					"id": completion_id,
					"object": "chat.completion.chunk",
					"created": created_time,
					"model": request.model,
					"choices": [{"index": 0, "delta": {"role": "assistant"}, "finish_reason": None}],
				}
				yield f"data: {json.dumps(data)}\n\n"

				# 模拟流式输出 - 将文本按字符分割发送
				for char in reply_text:
					data = {
						"id": completion_id,
						"object": "chat.completion.chunk",
						"created": created_time,
						"model": request.model,
						"choices": [{"index": 0, "delta": {"content": char}, "finish_reason": None}],
					}
					yield f"data: {json.dumps(data)}\n\n"
					# 可选：添加短暂延迟以模拟真实的流式输出
					await asyncio.sleep(0.01)

				# 发送结束事件
				data = {
					"id": completion_id,
					"object": "chat.completion.chunk",
					"created": created_time,
					"model": request.model,
					"choices": [{"index": 0, "delta": {}, "finish_reason": "stop"}],
				}
				yield f"data: {json.dumps(data)}\n\n"
				yield "data: [DONE]\n\n"

			return StreamingResponse(generate_stream(), media_type="text/event-stream")
		else:
			# 非流式响应（原来的逻辑）
			result = {
				"id": completion_id,
				"object": "chat.completion",
				"created": created_time,
				"model": request.model,
				"choices": [{"index": 0, "message": {"role": "assistant", "content": reply_text}, "finish_reason": "stop"}],
				"usage": {
					"prompt_tokens": len(conversation.split()),
					"completion_tokens": len(reply_text.split()),
					"total_tokens": len(conversation.split()) + len(reply_text.split()),
				},
			}

			logger.info(f"Returning response: {result}")
			return result

	except Exception as e:
		logger.error(f"Error generating completion: {str(e)}", exc_info=True)
		raise HTTPException(status_code=500, detail=f"Error generating completion: {str(e)}")


@app.get("/")
async def root():
	return {"status": "online", "message": "Gemini API FastAPI Server is running"}


if __name__ == "__main__":
	import uvicorn

	uvicorn.run("main:app", host="0.0.0.0", port=8000, log_level="info")