#
#  Copyright 2025 The InfiniFlow Authors. All Rights Reserved.
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
#
"""
OCR PDF处理服务的主程序入口
独立运行，不依赖RAGFlow的其他部分
"""

import argparse
import logging
import os
import sys
import signal
from pathlib import Path

# 确保项目根目录在 sys.path 中
_current_file = Path(__file__).resolve()
_project_root = _current_file.parent.parent
if str(_project_root) not in sys.path:
    sys.path.insert(0, str(_project_root))

import uvicorn
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

from ocr.api import ocr_router
from ocr.config import MODEL_DIR

# 配置日志
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
    handlers=[
        logging.StreamHandler(sys.stdout)
    ]
)

logger = logging.getLogger(__name__)


def create_app() -> FastAPI:
    """创建FastAPI应用实例"""
    app = FastAPI(
        title="OCR PDF Parser API",
        description="独立的OCR PDF处理服务，提供PDF文档的OCR识别功能",
        version="1.0.0",
        docs_url="/apidocs",  # Swagger UI 文档地址
        redoc_url="/redoc",   # ReDoc 文档地址（备用）
        openapi_url="/openapi.json"  # OpenAPI JSON schema 地址
    )
    
    # 添加CORS中间件
    app.add_middleware(
        CORSMiddleware,
        allow_origins=["*"],  # 生产环境中应该设置具体的域名
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )
    
    # 注册OCR路由
    app.include_router(ocr_router)
    
    # 根路径
    @app.get("/")
    async def root():
        return {
            "service": "OCR PDF Parser",
            "version": "1.0.0",
            "docs": "/apidocs",
            "health": "/api/v1/ocr/health"
        }
    
    return app


def signal_handler(sig, frame):
    """信号处理器，用于优雅关闭"""
    logger.info("Received shutdown signal, exiting...")
    sys.exit(0)


def main():
    """主函数"""
    parser = argparse.ArgumentParser(description="OCR PDF处理服务")
    parser.add_argument(
        "--host",
        type=str,
        default="0.0.0.0",
        help="服务器监听地址 (default: 0.0.0.0)"
    )
    parser.add_argument(
        "--port",
        type=int,
        default=8000,
        help="服务器端口 (default: 8000)"
    )
    parser.add_argument(
        "--reload",
        action="store_true",
        help="开发模式：自动重载代码"
    )
    parser.add_argument(
        "--workers",
        type=int,
        default=1,
        help="工作进程数 (default: 1)"
    )
    parser.add_argument(
        "--log-level",
        type=str,
        default="info",
        choices=["critical", "error", "warning", "info", "debug", "trace"],
        help="日志级别 (default: info)"
    )
    parser.add_argument(
        "--model-dir",
        type=str,
        default=None,
        help=f"OCR模型目录路径 (default: {MODEL_DIR})"
    )
    
    args = parser.parse_args()
    
    # 设置模型目录（如果提供）
    if args.model_dir:
        os.environ["OCR_MODEL_DIR"] = args.model_dir
        logger.info(f"Using custom model directory: {args.model_dir}")
    
    # 检查模型目录
    model_dir = os.environ.get("OCR_MODEL_DIR", MODEL_DIR)
    if model_dir and not os.path.exists(model_dir):
        logger.warning(f"Model directory does not exist: {model_dir}")
        logger.info("Models will be downloaded on first use")
    
    # 注册信号处理器
    signal.signal(signal.SIGINT, signal_handler)
    signal.signal(signal.SIGTERM, signal_handler)
    
    # 显示启动信息
    logger.info("=" * 60)
    logger.info("OCR PDF Parser Service")
    logger.info("=" * 60)
    logger.info(f"Host: {args.host}")
    logger.info(f"Port: {args.port}")
    logger.info(f"Model Directory: {model_dir}")
    logger.info(f"Workers: {args.workers}")
    logger.info(f"Reload: {args.reload}")
    logger.info(f"Log Level: {args.log_level}")
    logger.info("=" * 60)
    logger.info(f"API Documentation (Swagger): http://{args.host}:{args.port}/apidocs")
    logger.info(f"API Documentation (ReDoc): http://{args.host}:{args.port}/redoc")
    logger.info(f"Health Check: http://{args.host}:{args.port}/api/v1/ocr/health")
    logger.info("=" * 60)
    
    # 创建应用
    app = create_app()
    
    # 启动服务器
    try:
        uvicorn.run(
            app,
            host=args.host,
            port=args.port,
            log_level=args.log_level,
            reload=args.reload,
            workers=args.workers if not args.reload else 1,  # reload模式不支持多进程
            access_log=True
        )
    except KeyboardInterrupt:
        logger.info("Server stopped by user")
    except Exception as e:
        logger.error(f"Server error: {e}", exc_info=True)
        sys.exit(1)


if __name__ == "__main__":
    main()