package com.rongyichuang.judge.service;

import com.qcloud.cos.COSClient;
import com.qcloud.cos.ClientConfig;
import com.qcloud.cos.auth.BasicCOSCredentials;
import com.qcloud.cos.auth.COSCredentials;
import com.qcloud.cos.auth.COSSigner;
import com.qcloud.cos.http.HttpMethodName;
import com.qcloud.cos.region.Region;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

import java.time.Instant;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

@Service
public class CosService {

    @Value("${cos.secret-id}")
    private String secretId;

    @Value("${cos.secret-key}")
    private String secretKey;

    @Value("${cos.bucket}")
    private String bucket;

    @Value("${cos.region}")
    private String region;

    /**
     * 生成腾讯云 COS 临时上传凭证
     */
    public Map<String, String> generateUploadCredentials(String fileName) {
        // 生成文件路径：按日期分目录
        String dateDir = new java.text.SimpleDateFormat("yyyyMMdd").format(new Date());
        String key = dateDir + "/" + fileName;

        // 设置临时密钥有效期（5分钟，减少时间以避免时间同步问题）
        long currentTime = System.currentTimeMillis();
        Date expiration = new Date(currentTime + 5 * 60 * 1000);
        
        System.out.println("=== COS预签名URL生成调试信息 ===");
        System.out.println("当前系统时间: " + new Date(currentTime));
        System.out.println("过期时间: " + expiration);
        System.out.println("当前Unix时间戳: " + (currentTime / 1000));
        System.out.println("过期Unix时间戳: " + ((currentTime + 5 * 60 * 1000) / 1000));
        System.out.println("文件Key: " + key);
        System.out.println("存储桶: " + bucket);
        System.out.println("地域: " + region);

        // 创建COS客户端
        COSCredentials cred = new BasicCOSCredentials(secretId, secretKey);
        ClientConfig clientConfig = new ClientConfig(new Region(region));
        COSClient cosClient = new COSClient(cred, clientConfig);
        
        try {
            // 生成预签名URL
            java.net.URL url = cosClient.generatePresignedUrl(bucket, key, expiration, HttpMethodName.PUT);
            String presignedUrl = url.toString();
            
            // 格式化过期时间
            String expirationStr = Instant.ofEpochMilli(expiration.getTime())
                    .atZone(ZoneId.of("Asia/Shanghai"))
                    .format(DateTimeFormatter.ISO_LOCAL_DATE_TIME);
            
            Map<String, String> credentials = new HashMap<>();
            credentials.put("bucket", bucket);
            credentials.put("region", region);
            credentials.put("key", key);
            credentials.put("presignedUrl", presignedUrl);
            credentials.put("expiration", expirationStr);

            return credentials;
        } finally {
            cosClient.shutdown();
        }
    }

    /**
     * 直接上传文件到COS
     */
    public String uploadFile(org.springframework.web.multipart.MultipartFile file, String fileName) throws Exception {
        // 生成文件路径：按日期分目录
        String dateDir = new java.text.SimpleDateFormat("yyyyMMdd").format(new Date());
        String key = dateDir + "/" + fileName;
        
        System.out.println("=== COS文件上传调试信息 ===");
        System.out.println("文件Key: " + key);
        System.out.println("文件大小: " + file.getSize());
        System.out.println("文件类型: " + file.getContentType());
        
        // 创建COS客户端
        COSCredentials cred = new BasicCOSCredentials(secretId, secretKey);
        ClientConfig clientConfig = new ClientConfig(new Region(region));
        COSClient cosClient = new COSClient(cred, clientConfig);
        
        try {
            // 创建上传请求
            com.qcloud.cos.model.PutObjectRequest putObjectRequest = 
                new com.qcloud.cos.model.PutObjectRequest(bucket, key, file.getInputStream(), null);
            
            // 设置文件元数据
            com.qcloud.cos.model.ObjectMetadata metadata = new com.qcloud.cos.model.ObjectMetadata();
            metadata.setContentLength(file.getSize());
            if (file.getContentType() != null) {
                metadata.setContentType(file.getContentType());
            }
            putObjectRequest.setMetadata(metadata);
            
            // 执行上传
            com.qcloud.cos.model.PutObjectResult result = cosClient.putObject(putObjectRequest);
            System.out.println("上传成功，ETag: " + result.getETag());
            
            return key; // 返回相对路径
        } finally {
            cosClient.shutdown();
        }
    }

    /**
     * 获取文件访问 URL
     */
    public String getFileUrl(String key) {
        COSCredentials cred = new BasicCOSCredentials(secretId, secretKey);
        ClientConfig clientConfig = new ClientConfig(new Region(region));
        COSClient cosClient = new COSClient(cred, clientConfig);
        
        try {
            return cosClient.getObjectUrl(bucket, key).toString();
        } finally {
            cosClient.shutdown();
        }
    }
}