import "server-only";

import { S3Client, PutObjectCommand } from "@aws-sdk/client-s3";
import { put } from "@vercel/blob";
import { getDefaultStorageConfig } from "@/lib/db/queries";

// 获取文件的 Content-Type
function getContentType(filename: string): string {
  const ext = filename.toLowerCase().split(".").pop();
  const types: Record<string, string> = {
    jpg: "image/jpeg",
    jpeg: "image/jpeg",
    png: "image/png",
    gif: "image/gif",
    webp: "image/webp",
    svg: "image/svg+xml",
    pdf: "application/pdf",
    json: "application/json",
    txt: "text/plain",
    html: "text/html",
    css: "text/css",
    js: "application/javascript",
  };
  return types[ext ?? ""] ?? "application/octet-stream";
}

// S3/MinIO 上传函数（使用 AWS SDK）
async function uploadToS3(
  filename: string,
  buffer: ArrayBuffer,
  config: {
    endpoint: string;
    region: string;
    bucket: string;
    accessKeyId: string;
    secretAccessKey: string;
    publicUrl?: string;
  }
) {
  const { endpoint, region, bucket, accessKeyId, secretAccessKey, publicUrl } = config;

  // 生成唯一的文件名
  const timestamp = Date.now();
  const randomString = Math.random().toString(36).slice(2, 8);
  const ext = filename.split(".").pop();
  const key = `uploads/${timestamp}-${randomString}.${ext}`;

  const contentType = getContentType(filename);

  try {
    // 创建 S3 客户端（支持 MinIO）
    const s3Client = new S3Client({
      endpoint: endpoint,
      region: region || "auto",
      credentials: {
        accessKeyId: accessKeyId,
        secretAccessKey: secretAccessKey,
      },
      // 关键：MinIO 需要使用 path-style URL
      forcePathStyle: true,
    });

    console.log(`[S3 Upload] Uploading to: ${endpoint}/${bucket}/${key}`);

    // 上传文件
    const command = new PutObjectCommand({
      Bucket: bucket,
      Key: key,
      Body: Buffer.from(buffer),
      ContentType: contentType,
      // 设置为公开可读（如果您的 MinIO 桶支持）
      ACL: "public-read",
    });

    await s3Client.send(command);

    console.log(`[S3 Upload] Upload successful: ${key}`);

    // 返回文件的公开 URL
    // MinIO 的公开 URL 格式通常是: http://endpoint:port/bucket/key
    let fileUrl: string;
    if (publicUrl) {
      // 如果用户配置了自定义公开 URL，使用它
      fileUrl = `${publicUrl}/${key}`;
    } else {
      // 否则使用 endpoint + bucket + key
      const cleanEndpoint = endpoint.replace(/\/$/, ""); // 移除末尾的斜杠
      fileUrl = `${cleanEndpoint}/${bucket}/${key}`;
    }

    console.log(`[S3 Upload] File URL: ${fileUrl}`);

    return {
      url: fileUrl,
      pathname: key,
      contentType,
    };
  } catch (error) {
    console.error("[S3 Upload] Error:", error);
    throw error;
  }
}

// 上传文件到存储服务
export async function uploadFile(
  filename: string,
  buffer: ArrayBuffer
): Promise<{ url: string; pathname: string; contentType: string }> {
  console.log(`[Upload] Starting upload for file: ${filename}`);

  try {
    // 尝试从数据库获取存储配置
    const storageConfig = await getDefaultStorageConfig();

    if (
      storageConfig &&
      storageConfig.type === "s3" &&
      storageConfig.endpoint &&
      storageConfig.bucket &&
      storageConfig.accessKeyId &&
      storageConfig.secretAccessKey &&
      storageConfig.isEnabled
    ) {
      console.log(`[Upload] Using database S3 config: ${storageConfig.name}`);
      console.log(`[Upload] Endpoint: ${storageConfig.endpoint}`);
      console.log(`[Upload] Bucket: ${storageConfig.bucket}`);

      // 使用数据库配置的 S3/MinIO 存储
      return await uploadToS3(filename, buffer, {
        endpoint: storageConfig.endpoint,
        region: storageConfig.region ?? "auto",
        bucket: storageConfig.bucket,
        accessKeyId: storageConfig.accessKeyId,
        secretAccessKey: storageConfig.secretAccessKey,
        publicUrl: storageConfig.publicUrl ?? undefined,
      });
    } else {
      console.warn("[Upload] No valid S3 config in database");
    }
  } catch (error) {
    console.error("[Upload] Failed to get storage config from database:", error);
  }

  // 回退到环境变量配置的 S3
  if (
    process.env.S3_ENDPOINT &&
    process.env.S3_BUCKET &&
    process.env.S3_ACCESS_KEY_ID &&
    process.env.S3_SECRET_ACCESS_KEY
  ) {
    console.log("[Upload] Using environment variable S3 config");
    return await uploadToS3(filename, buffer, {
      endpoint: process.env.S3_ENDPOINT,
      region: process.env.S3_REGION ?? "auto",
      bucket: process.env.S3_BUCKET,
      accessKeyId: process.env.S3_ACCESS_KEY_ID,
      secretAccessKey: process.env.S3_SECRET_ACCESS_KEY,
      publicUrl: process.env.S3_PUBLIC_URL,
    });
  }

  // 最终回退到 Vercel Blob
  console.log("[Upload] Falling back to Vercel Blob");
  const data = await put(filename, buffer, {
    access: "public",
  });

  return {
    url: data.url,
    pathname: data.pathname,
    contentType: getContentType(filename),
  };
}

// 获取当前使用的存储类型
export async function getStorageType(): Promise<
  "database-s3" | "env-s3" | "vercel-blob"
> {
  try {
    const storageConfig = await getDefaultStorageConfig();
    if (
      storageConfig &&
      storageConfig.type === "s3" &&
      storageConfig.endpoint &&
      storageConfig.bucket
    ) {
      return "database-s3";
    }
  } catch (error) {
    // ignore
  }

  if (process.env.S3_ENDPOINT && process.env.S3_BUCKET) {
    return "env-s3";
  }

  return "vercel-blob";
}