#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Amazon商品数据爬虫 V2
使用万邦API按关键字搜索商品并保存结果
支持配置文件和命令行参数
"""

import requests
import json
import time
import os
import sys
import argparse
from pathlib import Path
from typing import Optional, Dict, Any
from datetime import datetime
import logging

# 配置日志
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(levelname)s - %(message)s',
    handlers=[
        logging.FileHandler('amazon_crawler.log'),
        logging.StreamHandler()
    ]
)
logger = logging.getLogger(__name__)


class AmazonCrawler:
    """亚马逊商品爬虫类"""
    
    def __init__(self, api_key: str, api_secret: str, results_dir: str = "amazon_results"):
        """
        初始化爬虫
        
        Args:
            api_key: API调用key
            api_secret: API调用密钥
            results_dir: 结果保存目录
        """
        self.api_key = api_key
        self.api_secret = api_secret
        self.base_url = "https://api-gw.onebound.cn/amazon/item_search"
        self.api_name = "item_search"
        
        # 创建结果保存目录
        self.results_dir = Path(results_dir)
        self.results_dir.mkdir(parents=True, exist_ok=True)
        
        # 请求统计
        self.total_requests = 0
        self.successful_requests = 0
        self.failed_requests = 0
        self.start_time = None
    
    def search_items(self, query: str, **kwargs) -> Optional[Dict[str, Any]]:
        """
        按关键字搜索商品
        
        Args:
            query: 搜索关键字
            **kwargs: 其他可选参数
            
        Returns:
            API响应的JSON数据，失败返回None
        """
        params = {
            'key': self.api_key,
            'secret': self.api_secret,
            'q': query,
            'cache': kwargs.get('cache', 'yes'),
            'result_type': kwargs.get('result_type', 'json'),
            'lang': kwargs.get('lang', 'cn'),
        }
        
        # 添加其他可选参数
        optional_params = ['start_price', 'end_price', 'page', 'cat', 
                          'discount_only', 'sort', 'page_size', 'seller_info', 
                          'nick', 'ppath']
        for param in optional_params:
            if param in kwargs and kwargs[param]:
                params[param] = kwargs[param]
        
        try:
            logger.info(f"正在请求: {query}")
            self.total_requests += 1
            
            response = requests.get(
                self.base_url,
                params=params,
                timeout=30
            )
            response.raise_for_status()
            
            data = response.json()
            
            if data.get('error_code') == '0000':
                logger.info(f"✓ 成功: {query} - 获得 {data.get('items', {}).get('real_total_results', 0)} 个结果")
                self.successful_requests += 1
                return data
            else:
                logger.error(f"✗ API错误: {query} - {data.get('reason', 'Unknown error')}")
                self.failed_requests += 1
                return data
                
        except requests.exceptions.RequestException as e:
            logger.error(f"✗ 请求失败: {query} - {str(e)}")
            self.failed_requests += 1
            return None
        except json.JSONDecodeError as e:
            logger.error(f"✗ JSON解析失败: {query} - {str(e)}")
            self.failed_requests += 1
            return None
    
    def save_result(self, query: str, data: Dict[str, Any], index: int):
        """保存搜索结果到JSON文件"""
        safe_query = "".join(c if c.isalnum() or c in (' ', '_', '-') else '_' 
                           for c in query)
        safe_query = safe_query.replace(' ', '_')[:50]
        
        filename = f"{index:04d}_{safe_query}.json"
        filepath = self.results_dir / filename
        
        try:
            with open(filepath, 'w', encoding='utf-8') as f:
                json.dump(data, f, ensure_ascii=False, indent=2)
            logger.debug(f"已保存: {filename}")
        except Exception as e:
            logger.error(f"保存失败: {filename} - {str(e)}")
    
    def crawl_from_file(self, queries_file: str, delay: float = 1.0, 
                       start_index: int = 0, max_queries: Optional[int] = None):
        """从文件读取查询列表并批量爬取"""
        self.start_time = datetime.now()
        logger.info("=" * 70)
        logger.info(f"Amazon爬虫启动 - {self.start_time.strftime('%Y-%m-%d %H:%M:%S')}")
        logger.info("=" * 70)
        logger.info(f"查询文件: {queries_file}")
        logger.info(f"结果目录: {self.results_dir}")
        
        try:
            with open(queries_file, 'r', encoding='utf-8') as f:
                queries = [line.strip() for line in f if line.strip()]
            
            total_queries = len(queries)
            logger.info(f"共读取 {total_queries} 个查询")
            
            if start_index > 0:
                queries = queries[start_index:]
                logger.info(f"从索引 {start_index} 开始")
            
            if max_queries:
                queries = queries[:max_queries]
                logger.info(f"限制爬取数量: {max_queries}")
            
            logger.info(f"请求间隔: {delay} 秒")
            logger.info("=" * 70)
            
            # 逐个爬取
            for i, query in enumerate(queries, start=start_index):
                progress = i - start_index + 1
                total = len(queries)
                percentage = (progress / total) * 100
                
                logger.info(f"[{progress}/{total}] ({percentage:.1f}%) - {query}")
                
                data = self.search_items(query)
                
                if data:
                    self.save_result(query, data, i)
                else:
                    error_data = {
                        'error': 'Request failed',
                        'query': query,
                        'index': i,
                        'timestamp': datetime.now().isoformat()
                    }
                    self.save_result(query, error_data, i)
                
                # 延迟
                if progress < total:
                    time.sleep(delay)
            
            # 统计信息
            end_time = datetime.now()
            duration = end_time - self.start_time
            
            logger.info("=" * 70)
            logger.info("爬取完成！")
            logger.info("=" * 70)
            logger.info(f"开始时间: {self.start_time.strftime('%Y-%m-%d %H:%M:%S')}")
            logger.info(f"结束时间: {end_time.strftime('%Y-%m-%d %H:%M:%S')}")
            logger.info(f"总耗时: {duration}")
            logger.info(f"总请求数: {self.total_requests}")
            logger.info(f"成功: {self.successful_requests} ({self.successful_requests/self.total_requests*100:.1f}%)")
            logger.info(f"失败: {self.failed_requests} ({self.failed_requests/self.total_requests*100:.1f}%)")
            logger.info(f"结果保存在: {self.results_dir.absolute()}")
            logger.info("=" * 70)
            
        except FileNotFoundError:
            logger.error(f"文件不存在: {queries_file}")
        except KeyboardInterrupt:
            logger.warning("\n用户中断爬取")
            logger.info(f"已完成: {self.successful_requests}/{self.total_requests}")
        except Exception as e:
            logger.error(f"爬取过程出错: {str(e)}", exc_info=True)


def load_config():
    """加载配置文件"""
    try:
        # 尝试导入config.py
        import config
        return config
    except ImportError:
        logger.warning("未找到配置文件 config.py，使用默认配置")
        return None


def main():
    """主函数"""
    parser = argparse.ArgumentParser(description='Amazon商品数据爬虫')
    parser.add_argument('--key', type=str, help='API Key')
    parser.add_argument('--secret', type=str, help='API Secret')
    parser.add_argument('--queries', type=str, default='queries.txt',
                       help='查询文件路径')
    parser.add_argument('--delay', type=float, default=2.0,
                       help='请求间隔（秒）')
    parser.add_argument('--start', type=int, default=0,
                       help='起始索引')
    parser.add_argument('--max', type=int, default=None,
                       help='最大爬取数量')
    parser.add_argument('--output', type=str, default='amazon_results',
                       help='结果保存目录')
    
    args = parser.parse_args()
    
    # 获取API密钥
    api_key = args.key
    api_secret = args.secret
    
    # 如果命令行没有提供，尝试从配置文件加载
    if not api_key or not api_secret:
        config = load_config()
        if config:
            api_key = api_key or getattr(config, 'API_KEY', None)
            api_secret = api_secret or getattr(config, 'API_SECRET', None)
    
    # 如果仍然没有，尝试从环境变量读取
    if not api_key or not api_secret:
        api_key = api_key or os.getenv('ONEBOUND_API_KEY')
        api_secret = api_secret or os.getenv('ONEBOUND_API_SECRET')
    
    # 检查API密钥
    if not api_key or not api_secret or \
       api_key == "your_api_key_here" or api_secret == "your_api_secret_here":
        logger.error("=" * 70)
        logger.error("错误: 未配置API密钥！")
        logger.error("")
        logger.error("请使用以下任一方式配置API密钥：")
        logger.error("1. 命令行参数: --key YOUR_KEY --secret YOUR_SECRET")
        logger.error("2. 配置文件: 复制 config.example.py 为 config.py 并填入密钥")
        logger.error("3. 环境变量: ONEBOUND_API_KEY 和 ONEBOUND_API_SECRET")
        logger.error("=" * 70)
        return
    
    # 创建爬虫实例
    crawler = AmazonCrawler(api_key, api_secret, args.output)
    
    # 开始爬取
    crawler.crawl_from_file(
        queries_file=args.queries,
        delay=args.delay,
        start_index=args.start,
        max_queries=args.max
    )


if __name__ == "__main__":
    main()