#
#  Copyright 2025 The InfiniFlow Authors. All Rights Reserved.
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#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
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#      http://www.apache.org/licenses/LICENSE-2.0
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#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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"""
OCR HTTP 客户端
用于调用独立的 OCR 服务的 HTTP API
"""

import os
import logging
import requests
from typing import Optional, Union, Dict, Any

logger = logging.getLogger(__name__)


class OCRHttpClient:
    """OCR HTTP 客户端，用于调用独立的 OCR 服务"""
    
    def __init__(self, base_url: Optional[str] = None, timeout: int = 300):
        """
        初始化 OCR HTTP 客户端
        
        Args:
            base_url: OCR 服务的基础 URL，如果不提供则从环境变量 OCR_SERVICE_URL 读取
                     默认值为 http://localhost:8000
            timeout: 请求超时时间（秒），默认 300 秒
        """
        if base_url is None:
            base_url = os.getenv("OCR_SERVICE_URL", "http://localhost:8000")
        
        # 确保 URL 不包含尾随斜杠
        self.base_url = base_url.rstrip("/")
        self.timeout = timeout
        self.api_prefix = "/api/v1/ocr"
        
        logger.info(f"Initialized OCR HTTP client with base_url: {self.base_url}")
    
    def parse_pdf_by_path(self, file_path: str, page_from: int = 1, page_to: int = 0, zoomin: int = 3) -> Dict[str, Any]:
        """
        通过文件路径解析 PDF
        
        Args:
            file_path: PDF 文件的本地路径
            page_from: 起始页码（从1开始）
            page_to: 结束页码（0表示最后一页）
            zoomin: 图像放大倍数（1-5）
            
        Returns:
            dict: 解析结果，格式：
                {
                    "success": bool,
                    "message": str,
                    "data": {
                        "pages": [
                            {
                                "page_number": int,
                                "boxes": [
                                    {
                                        "text": str,
                                        "bbox": [[x0, y0], [x1, y0], [x1, y1], [x0, y1]],
                                        "confidence": float
                                    },
                                    ...
                                ]
                            },
                            ...
                        ]
                    }
                }
            
        Raises:
            requests.RequestException: HTTP 请求失败
            ValueError: 响应格式不正确
        """
        url = f"{self.base_url}{self.api_prefix}/parse/path"
        
        data = {
            "file_path": file_path,
            "page_from": page_from,
            "page_to": page_to,
            "zoomin": zoomin
        }
        
        try:
            logger.info(f"Calling OCR service: {url} for file: {file_path}")
            response = requests.post(url, data=data, timeout=self.timeout)
            response.raise_for_status()
            
            result = response.json()
            if not result.get("success", False):
                raise ValueError(f"OCR service returned error: {result.get('message', 'Unknown error')}")
            
            return result
            
        except requests.RequestException as e:
            logger.error(f"Failed to call OCR service: {e}")
            raise
    
    def parse_pdf_by_bytes(self, pdf_bytes: bytes, filename: str = "document.pdf", 
                          page_from: int = 1, page_to: int = 0, zoomin: int = 3) -> Dict[str, Any]:
        """
        通过二进制数据解析 PDF
        
        Args:
            pdf_bytes: PDF 文件的二进制数据
            filename: 文件名（仅用于日志）
            page_from: 起始页码（从1开始）
            page_to: 结束页码（0表示最后一页）
            zoomin: 图像放大倍数（1-5）
            
        Returns:
            dict: 解析结果，格式同 parse_pdf_by_path
            
        Raises:
            requests.RequestException: HTTP 请求失败
            ValueError: 响应格式不正确
        """
        url = f"{self.base_url}{self.api_prefix}/parse/bytes"
        
        files = {
            "pdf_bytes": (filename, pdf_bytes, "application/pdf")
        }
        
        data = {
            "filename": filename,
            "page_from": page_from,
            "page_to": page_to,
            "zoomin": zoomin
        }
        
        try:
            logger.info(f"Calling OCR service: {url} with {len(pdf_bytes)} bytes")
            response = requests.post(url, files=files, data=data, timeout=self.timeout)
            response.raise_for_status()
            
            result = response.json()
            if not result.get("success", False):
                raise ValueError(f"OCR service returned error: {result.get('message', 'Unknown error')}")
            
            return result
            
        except requests.RequestException as e:
            logger.error(f"Failed to call OCR service: {e}")
            raise
    
    def health_check(self) -> Dict[str, Any]:
        """
        检查 OCR 服务健康状态
        
        Returns:
            dict: 健康状态信息
        """
        url = f"{self.base_url}{self.api_prefix}/health"
        
        try:
            response = requests.get(url, timeout=10)
            response.raise_for_status()
            return response.json()
        except requests.RequestException as e:
            logger.error(f"Failed to check OCR service health: {e}")
            raise