import { NextRequest, NextResponse } from "next/server";
import { getSystemSetting } from "@/lib/db/queries";
import { auth } from "@/app/(auth)/auth";
import { uploadFile } from "@/lib/storage/service";
import { db } from "@/lib/db";
import { generatedImage } from "@/lib/db/schema";

/**
 * 压缩图片生成缩略图（使用 sharp）
 */
async function createThumbnail(buffer: Buffer, mimeType: string): Promise<Buffer> {
  try {
    const sharp = await import("sharp");
    
    // 创建缩略图（宽度 500px，高度按比例，质量 80%）
    const thumbnailBuffer = await sharp.default(buffer)
      .resize(500, null, {
        fit: "inside",
        withoutEnlargement: true,
      })
      .jpeg({ quality: 80 }) // JPEG格式
      .toBuffer();
    
    console.log(`[Enhance] Thumbnail created, size: ${thumbnailBuffer.length} bytes (original: ${buffer.length} bytes)`);
    return thumbnailBuffer;
  } catch (error) {
    console.error("[Enhance] Failed to create thumbnail:", error);
    // 如果失败，返回原图
    return buffer;
  }
}

/**
 * 将 base64 图片上传到 S3，返回缩略图和原图的 URL
 */
async function uploadBase64ToS3(base64Data: string, mimeType: string = "image/jpeg"): Promise<{ thumbnail: string; original: string }> {
  try {
    // 解析 base64 数据
    const buffer = Buffer.from(base64Data, "base64");
    
    // 生成文件名
    const ext = mimeType.split("/")[1] || "jpg";
    const timestamp = Date.now();
    const randomStr = Math.random().toString(36).slice(2, 8);
    const thumbnailFilename = `enhance-thumb-${timestamp}-${randomStr}.${ext}`;
    const originalFilename = `enhance-orig-${timestamp}-${randomStr}.${ext}`;
    
    console.log(`[Enhance] Original size: ${buffer.length} bytes`);
    
    // 生成缩略图
    const thumbnailBuffer = await createThumbnail(buffer, mimeType);
    
    // 转换为 ArrayBuffer
    const thumbnailArrayBuffer = thumbnailBuffer.buffer.slice(
      thumbnailBuffer.byteOffset, 
      thumbnailBuffer.byteOffset + thumbnailBuffer.byteLength
    ) as ArrayBuffer;
    const originalArrayBuffer = buffer.buffer.slice(
      buffer.byteOffset, 
      buffer.byteOffset + buffer.byteLength
    ) as ArrayBuffer;
    
    // 并行上传缩略图和原图到 S3
    console.log(`[Enhance] Uploading thumbnail and original to S3...`);
    const [thumbnailResult, originalResult] = await Promise.all([
      uploadFile(thumbnailFilename, thumbnailArrayBuffer),
      uploadFile(originalFilename, originalArrayBuffer),
    ]);
    
    console.log(`[Enhance] Uploaded to S3:`);
    console.log(`  - Thumbnail: ${thumbnailResult.url}`);
    console.log(`  - Original: ${originalResult.url}`);
    
    return {
      thumbnail: thumbnailResult.url,
      original: originalResult.url,
    };
  } catch (error) {
    console.error("[Enhance] Failed to upload to S3:", error);
    throw new Error(`图片上传到存储桶失败: ${error instanceof Error ? error.message : "未知错误"}。请检查系统设置中的存储配置。`);
  }
}

// 设置API路由最大执行时间为3分钟（180秒）
export const maxDuration = 180;

/**
 * 轮询获取任务结果（根据官方示例）
 */
async function pollTaskResult(
  apiUrl: string, 
  apiKey: string, 
  taskId: string, 
  delay: number = 1000, 
  timeout: number = 120000 // 增加到120秒（2分钟）
): Promise<any> {
  const pollUrl = `${apiUrl}/api/tasks/visual/scale/${taskId}`;
  
  const getTaskResult = async (): Promise<any> => {
    const response = await fetch(pollUrl, {
      method: "GET",
      headers: {
        "X-API-KEY": apiKey,
      },
    });

    if (!response.ok) {
      throw new Error(`轮询请求失败: ${response.status} ${response.statusText}`);
    }

    const result = await response.json();
    
    if (!result.data) {
      throw result;
    }
    
    const { progress, state } = result.data;
    
    // state < 0 表示失败
    if (state < 0) {
      throw result;
    }
    
    // progress >= 100 表示完成
    if (progress >= 100) {
      return result;
    }
    
    // 否则继续轮询
    throw null;
  };
  
  try {
    const result = await getTaskResult();
    return result;
  } catch (error) {
    if (error && typeof error === 'object' && 'data' in error) {
      throw new Error(JSON.stringify(error, null, 2));
    }
    if (timeout <= 0) {
      throw new Error('轮询超时');
    }
    await new Promise((resolve) => {
      setTimeout(() => {
        resolve(undefined);
      }, delay);
    });
    return pollTaskResult(apiUrl, apiKey, taskId, delay, timeout - delay);
  }
}

/**
 * 图片变清晰API路由
 * 从数据库读取变清晰API配置，调用外部API进行图片增强处理
 * 将处理后的图片上传到S3并保存到数据库
 */
export async function POST(request: NextRequest) {
  console.log("[Enhance API] ===== 收到请求 =====");
  try {
    // 0. 获取用户会话
    console.log("[Enhance API] 开始获取用户会话...");
    const session = await auth();
    console.log("[Enhance API] 用户会话获取完成:", session?.user?.id ? "已登录" : "未登录");
    if (!session?.user?.id) {
      return NextResponse.json(
        { error: "未授权，请先登录" },
        { status: 401 }
      );
    }

    const userId = session.user.id;
    console.log("[Enhance API] 用户ID:", userId);
    // 1. 从数据库获取变清晰API配置
    console.log("[Enhance API] 开始获取配置...");
    const enhanceConfig = await getSystemSetting({ key: "enhance_api_config" });
    console.log("[Enhance API] 配置获取完成:", enhanceConfig ? "已找到" : "未找到");
    
    if (!enhanceConfig || !enhanceConfig.value) {
      return NextResponse.json(
        { error: "变清晰API配置未设置，请在系统设置中配置" },
        { status: 400 }
      );
    }

    const config = enhanceConfig.value as {
      apiUrl?: string;
      apiKey?: string;
      type?: string; // "clean" | "face"
      scaleFactor?: number | string; // 1 | 2 | 4 | "auto"
    };

    if (!config.apiUrl || !config.apiKey) {
      return NextResponse.json(
        { error: "变清晰API地址或密钥未配置" },
        { status: 400 }
      );
    }

    // 2. 获取请求体（Base64图片或FormData）
    console.log("[Enhance API] 开始获取请求体...");
    const contentType = request.headers.get("content-type") || "";
    console.log("[Enhance API] Content-Type:", contentType);
    
    let imageBase64: string;
    let prompt = ""; // 用户提示词（可选）
    let chatId: string | null = null; // 聊天ID（可选）
    let messageId: string | null = null; // 消息ID（可选）
    
    if (contentType.includes("application/json")) {
      // JSON格式：Base64图片
      console.log("[Enhance API] 解析JSON请求体...");
      const body = await request.json();
      console.log("[Enhance API] JSON请求体解析完成，image_base64长度:", body.image_base64?.length || 0);
      imageBase64 = body.image_base64;
      prompt = body.prompt || "图片变清晰处理";
      chatId = body.chatId || null;
      messageId = body.messageId || null;
      
      if (!imageBase64) {
        return NextResponse.json(
          { error: "缺少image_base64参数" },
          { status: 400 }
        );
      }
    } else if (contentType.includes("multipart/form-data")) {
      // FormData格式：文件上传
      const formData = await request.formData();
      const file = formData.get("file") as File;
      
      if (!file) {
        return NextResponse.json(
          { error: "缺少file参数" },
          { status: 400 }
        );
      }

      // 将文件转换为Base64
      const arrayBuffer = await file.arrayBuffer();
      const buffer = Buffer.from(arrayBuffer);
      imageBase64 = buffer.toString("base64");
      prompt = (formData.get("prompt") as string) || "图片变清晰处理";
      chatId = (formData.get("chatId") as string) || null;
      messageId = (formData.get("messageId") as string) || null;
    } else {
      return NextResponse.json(
        { error: "不支持的Content-Type，请使用application/json或multipart/form-data" },
        { status: 400 }
      );
    }

    // 3. 调用变清晰API（使用异步模式，根据官方示例）
    const apiUrl = config.apiUrl.endsWith("/") 
      ? config.apiUrl.slice(0, -1) 
      : config.apiUrl;
    
    const enhanceUrl = `${apiUrl}/api/tasks/visual/scale`;
    
    // 将Base64转换为Buffer
    const imageBuffer = Buffer.from(imageBase64, "base64");
    
    // 创建FormData（使用form-data包，Node.js环境）
    const FormDataLib = await import("form-data");
    const formData = new FormDataLib.default();
    formData.append("image_file", imageBuffer, {
      filename: "image.jpg",
      contentType: "image/jpeg",
    });
    // 使用异步模式（sync=0），根据官方示例
    formData.append("sync", "0");
    formData.append("type", config.type || "clean"); // 默认通用清晰化
    const scaleFactorValue = typeof config.scaleFactor === "number" ? config.scaleFactor : (config.scaleFactor === "auto" ? undefined : Number.parseInt(String(config.scaleFactor)));
    if (scaleFactorValue) {
      formData.append("scale_factor", String(scaleFactorValue));
    }
    formData.append("return_type", "2"); // 返回base64

    const headers: Record<string, string> = {
      "X-API-KEY": config.apiKey,
      ...formData.getHeaders(), // 包含Content-Type和boundary
    };

    const startTime = Date.now();
    let taskId: string;
    
    try {
      // 添加超时控制（60秒）
      const controller = new AbortController();
      const timeoutId = setTimeout(() => controller.abort(), 60000);
      
      // 将FormData转换为Buffer（form-data包是stream）
      const formDataBuffer = await new Promise<Buffer>((resolve, reject) => {
        const chunks: Buffer[] = [];
        formData.on("data", (chunk: Buffer) => chunks.push(chunk));
        formData.on("end", () => resolve(Buffer.concat(chunks)));
        formData.on("error", reject);
      });
      
      // 将Buffer转换为Uint8Array用于fetch（更兼容）
      const uint8Array = new Uint8Array(formDataBuffer);
      
      const createResponse = await fetch(enhanceUrl, {
        method: "POST",
        headers,
        body: uint8Array,
        signal: controller.signal,
      });
      
      clearTimeout(timeoutId);
      
      if (!createResponse.ok) {
        const errorText = await createResponse.text();
        throw new Error(`创建任务失败: ${errorText || createResponse.statusText}`);
      }
      
      const createResult = await createResponse.json();
      
      if (!createResult.data || !createResult.data.task_id) {
        throw new Error(`API未返回task_id: ${JSON.stringify(createResult)}`);
      }
      
      taskId = createResult.data.task_id;
      console.log(`[Enhance] 任务已创建，task_id: ${taskId}`);
    } catch (fetchError) {
      const processingTime = (Date.now() - startTime) / 1000;
      console.error("[Enhance API] 网络请求失败:", {
        error: fetchError,
        enhanceUrl,
        processingTime,
      });
      
      // 检查是否是网络连接错误
      if (fetchError instanceof Error) {
        if (fetchError.name === 'AbortError') {
          return NextResponse.json(
            { 
              error: "变清晰API请求超时",
              detail: "创建任务请求超过60秒未响应，请检查API服务器状态或网络连接",
            },
            { status: 504 }
          );
        }
        
        // 检查错误消息和cause中的网络错误
        const errorMessage = fetchError.message || '';
        const errorCause = (fetchError as any).cause;
        const causeMessage = errorCause?.message || '';
        const causeCode = errorCause?.code || '';
        
        // 检查各种网络连接错误
        if (errorMessage.includes('EHOSTUNREACH') || 
            errorMessage.includes('ENOTFOUND') ||
            errorMessage.includes('ECONNREFUSED') ||
            errorMessage.includes('No route to host') ||
            causeMessage.includes('EHOSTUNREACH') ||
            causeMessage.includes('ENOTFOUND') ||
            causeMessage.includes('ECONNREFUSED') ||
            causeMessage.includes('No route to host') ||
            causeCode === 'EHOSTUNREACH' ||
            causeCode === 'ENOTFOUND' ||
            causeCode === 'ECONNREFUSED') {
          return NextResponse.json(
            { 
              error: "无法连接到变清晰API服务器",
              detail: `服务器无法访问 ${enhanceUrl}，请检查：\n1. API服务器是否在线\n2. 网络连接是否正常\n3. 防火墙设置是否正确\n4. API地址和密钥是否正确`,
            },
            { status: 503 }
          );
        }
      }
      
      return NextResponse.json(
        { 
          error: "变清晰API请求失败",
          detail: fetchError instanceof Error ? fetchError.message : "未知网络错误",
        },
        { status: 500 }
      );
    }

      // 4. 轮询获取任务结果（根据官方示例）
      console.log(`[Enhance] 开始轮询任务结果，task_id: ${taskId}`);
      const taskResult = await pollTaskResult(apiUrl, config.apiKey, taskId);
      
      const finalProcessingTime = (Date.now() - startTime) / 1000;
      
      // 5. 处理返回结果
      if (taskResult.status !== 200 || !taskResult.data) {
        return NextResponse.json(
          { error: "变清晰处理失败", detail: taskResult.message || "未知错误" },
          { status: 500 }
        );
      }
      
      let enhancedImageBase64: string;
      
      if (taskResult.data.image_base64) {
        // 返回的是base64
        enhancedImageBase64 = taskResult.data.image_base64;
      } else if (taskResult.data.image) {
        // 返回的是URL，需要下载
        const imageResponse = await fetch(taskResult.data.image);
        if (!imageResponse.ok) {
          return NextResponse.json(
            { error: "变清晰处理失败", detail: "无法下载处理后的图片" },
            { status: 500 }
          );
        }
        const imageBuffer = await imageResponse.arrayBuffer();
        enhancedImageBase64 = Buffer.from(imageBuffer).toString("base64");
      } else {
        return NextResponse.json(
          { error: "变清晰处理失败", detail: "轮询结果未包含图片数据" },
          { status: 500 }
        );
      }

      if (!enhancedImageBase64) {
        return NextResponse.json(
          { error: "变清晰处理失败", detail: "无法获取处理后的图片" },
          { status: 500 }
        );
      }

    // 5. 上传处理后的图片到S3存储桶
    let thumbnailUrl: string;
    let originalUrl: string;
    
    try {
      const uploadResult = await uploadBase64ToS3(enhancedImageBase64, "image/jpeg");
      thumbnailUrl = uploadResult.thumbnail;
      originalUrl = uploadResult.original;
      console.log(`[Enhance] ✅ Images uploaded to S3 successfully`);
    } catch (uploadError) {
      console.error("[Enhance] ❌ Failed to upload to S3:", uploadError);
      return NextResponse.json(
        { 
          error: "图片上传到存储桶失败", 
          detail: uploadError instanceof Error ? uploadError.message : "未知错误" 
        },
        { status: 500 }
      );
    }

    // 6. 保存图片记录到数据库
    try {
      await db.insert(generatedImage).values({
        userId,
        chatId: chatId || null,
        messageId: messageId || null,
        thumbnailUrl,
        originalUrl,
        imageSize: "2K", // 默认尺寸
        prompt: prompt || "图片变清晰处理",
        modelId: "enhance-1.0", // 标记为变清晰处理
      });
      console.log(`[Enhance] ✅ Image record saved to database`);
    } catch (dbError) {
      console.error("[Enhance] ❌ Failed to save image record to database:", dbError);
      // 即使数据库保存失败，也返回成功（因为图片已上传到S3）
    }

    // 7. 返回结果（包含S3 URL和Base64，前端可以选择使用）
    return NextResponse.json({
      success: true,
      image_base64: enhancedImageBase64, // 保留Base64用于前端立即显示
      thumbnail_url: thumbnailUrl, // S3缩略图URL
      original_url: originalUrl, // S3原图URL
      processing_time: finalProcessingTime,
    });
  } catch (error) {
    console.error("[Enhance API] 处理错误:", error);
    return NextResponse.json(
      { error: "服务器内部错误", detail: error instanceof Error ? error.message : "未知错误" },
      { status: 500 }
    );
  }
}