import { NextRequest, NextResponse } from "next/server";
import { auth } from "@/app/(auth)/auth";
import { saveMessages, getMessagesByChatId } from "@/lib/db/queries";
import type { DBMessage } from "@/lib/db/schema";

export const dynamic = "force-dynamic";
export const revalidate = 0;

/**
 * 获取聊天消息
 * 用于从数据库重新加载消息
 */
export async function GET(request: NextRequest) {
  try {
    const session = await auth();
    
    if (!session?.user?.id) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const chatId = request.nextUrl.searchParams.get("chatId");
    
    if (!chatId) {
      return NextResponse.json(
        { error: "Missing required parameter: chatId" },
        { status: 400 }
      );
    }

    // 从数据库获取消息
    const messages = await getMessagesByChatId({ id: chatId });
    
    // 转换为前端格式
    const formattedMessages = messages.map((msg: DBMessage) => {
      const parts = msg.parts as any[] || [];
      const firstPart = parts[0] as any;
      return {
        id: msg.id,
        role: msg.role,
        content: firstPart?.text || "",
        createdAt: msg.createdAt,
        parts: parts,
        attachments: msg.attachments || [],
      };
    });

    return NextResponse.json(
      { messages: formattedMessages },
      {
        headers: {
          "Cache-Control": "no-store, max-age=0",
        },
      }
    );
  } catch (error) {
    console.error("[Messages API] GET Error:", error);
    return NextResponse.json(
      { error: "Failed to get messages" },
      { status: 500 }
    );
  }
}

/**
 * 保存消息到数据库的API
 * 用于图片处理等场景中保存助手回复消息
 */
export async function POST(request: NextRequest) {
  try {
    const session = await auth();
    
    if (!session?.user?.id) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const body = await request.json();
    const { chatId, message } = body;

    if (!chatId || !message) {
      return NextResponse.json(
        { error: "Missing required fields: chatId and message" },
        { status: 400 }
      );
    }

    // 构造DBMessage对象
    const dbMessage: DBMessage = {
      id: message.id,
      chatId,
      role: message.role || "assistant",
      parts: message.parts || [],
      attachments: message.attachments || [],
      createdAt: message.createdAt ? new Date(message.createdAt) : new Date(),
      videoStorageStatus: null,
      temporaryVideoUrl: null,
      permanentVideoUrl: null,
      archivedAt: null,
      videoMetadata: null,
    };

    // 保存消息到数据库
    await saveMessages({ messages: [dbMessage] });

    return NextResponse.json({ success: true });
  } catch (error) {
    console.error("[Messages API] Error:", error);
    return NextResponse.json(
      { error: "Failed to save message" },
      { status: 500 }
    );
  }
}