#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
缓存管理工具
用于管理视频识别过程中的临时缓存文件
"""

import os
import time
import argparse
from pathlib import Path

# 缓存目录配置
CACHE_DIR = os.path.join(os.path.dirname(__file__), 'cache')
CACHE_MAX_AGE = 3600  # 1小时

def get_cache_info():
    """获取缓存信息"""
    if not os.path.exists(CACHE_DIR):
        return {
            'exists': False,
            'total_files': 0,
            'total_size_mb': 0,
            'oldest_file': None,
            'newest_file': None
        }
    
    files = []
    total_size = 0
    
    for filename in os.listdir(CACHE_DIR):
        file_path = os.path.join(CACHE_DIR, filename)
        if os.path.isfile(file_path):
            stat = os.stat(file_path)
            files.append({
                'name': filename,
                'size': stat.st_size,
                'mtime': stat.st_mtime,
                'age': time.time() - stat.st_mtime
            })
            total_size += stat.st_size
    
    if not files:
        return {
            'exists': True,
            'total_files': 0,
            'total_size_mb': 0,
            'oldest_file': None,
            'newest_file': None
        }
    
    # 按修改时间排序
    files.sort(key=lambda x: x['mtime'])
    
    return {
        'exists': True,
        'total_files': len(files),
        'total_size_mb': total_size / (1024 * 1024),
        'oldest_file': {
            'name': files[0]['name'],
            'age_hours': files[0]['age'] / 3600
        },
        'newest_file': {
            'name': files[-1]['name'],
            'age_hours': files[-1]['age'] / 3600
        }
    }

def cleanup_cache(force=False, dry_run=False):
    """清理缓存文件"""
    if not os.path.exists(CACHE_DIR):
        print("缓存目录不存在")
        return 0
    
    current_time = time.time()
    cleaned_count = 0
    cleaned_size = 0
    
    for filename in os.listdir(CACHE_DIR):
        file_path = os.path.join(CACHE_DIR, filename)
        if os.path.isfile(file_path):
            file_age = current_time - os.path.getmtime(file_path)
            should_clean = force or file_age > CACHE_MAX_AGE
            
            if should_clean:
                file_size = os.path.getsize(file_path)
                if dry_run:
                    print(f"将要清理: {filename} (大小: {file_size/1024:.1f}KB, 年龄: {file_age/3600:.1f}小时)")
                else:
                    try:
                        os.remove(file_path)
                        cleaned_count += 1
                        cleaned_size += file_size
                        print(f"已清理: {filename}")
                    except Exception as e:
                        print(f"清理失败: {filename}, 错误: {e}")
    
    if not dry_run:
        print(f"清理完成: {cleaned_count} 个文件, 释放空间: {cleaned_size/(1024*1024):.2f}MB")
    
    return cleaned_count

def show_cache_status():
    """显示缓存状态"""
    info = get_cache_info()
    
    print("=" * 50)
    print("缓存状态信息")
    print("=" * 50)
    
    if not info['exists']:
        print("缓存目录不存在")
        return
    
    print(f"缓存目录: {CACHE_DIR}")
    print(f"文件数量: {info['total_files']}")
    print(f"总大小: {info['total_size_mb']:.2f} MB")
    
    if info['oldest_file']:
        print(f"最旧文件: {info['oldest_file']['name']} ({info['oldest_file']['age_hours']:.1f}小时前)")
    
    if info['newest_file']:
        print(f"最新文件: {info['newest_file']['name']} ({info['newest_file']['age_hours']:.1f}小时前)")
    
    # 显示文件列表
    if info['total_files'] > 0:
        print("\n文件列表:")
        print("-" * 50)
        if os.path.exists(CACHE_DIR):
            for filename in sorted(os.listdir(CACHE_DIR)):
                file_path = os.path.join(CACHE_DIR, filename)
                if os.path.isfile(file_path):
                    stat = os.stat(file_path)
                    age = time.time() - stat.st_mtime
                    size = stat.st_size
                    print(f"{filename:<30} {size/1024:>8.1f}KB {age/3600:>6.1f}小时前")

def main():
    """主函数"""
    parser = argparse.ArgumentParser(description='缓存管理工具')
    parser.add_argument('action', choices=['status', 'clean', 'cleanup'], 
                       help='操作类型: status(查看状态), clean(清理), cleanup(清理)')
    parser.add_argument('--force', '-f', action='store_true', 
                       help='强制清理所有文件（不检查年龄）')
    parser.add_argument('--dry-run', '-n', action='store_true', 
                       help='试运行模式，不实际删除文件')
    
    args = parser.parse_args()
    
    if args.action == 'status':
        show_cache_status()
    elif args.action in ['clean', 'cleanup']:
        if args.dry_run:
            print("试运行模式 - 不会实际删除文件")
            cleanup_cache(force=args.force, dry_run=True)
        else:
            print("开始清理缓存...")
            cleaned = cleanup_cache(force=args.force, dry_run=False)
            if cleaned > 0:
                print(f"清理完成，共清理 {cleaned} 个文件")
            else:
                print("没有需要清理的文件")

if __name__ == '__main__':
    main()