/**
 * GET /api/chats - Lista chats do usuário
 * POST /api/chats - Cria novo chat
 */

import { type NextRequest, NextResponse } from "next/server";
import { requireAuth } from "@/lib/auth/middleware";
import { connectMongoDB } from "@/lib/mongodb/connection";
import { Chat } from "@/lib/mongodb/models/Chat";
import { getMainCharacter } from "@/lib/prisma/queries/characters";
import { getListingById } from "@/lib/prisma/queries/listings";
import { getUserById } from "@/lib/prisma/queries/users";
import { secureLogger } from "@/lib/secure-logger";
import { createChatSchema } from "@/lib/validation/chat-schemas";

/**
 * GET /api/chats
 * Lista todos os chats do usuário autenticado
 */
export async function GET(request: NextRequest) {
  try {
    const authResult = await requireAuth(request);
    if (authResult instanceof NextResponse) return authResult;
    const auth = authResult;

    await connectMongoDB();

    // Buscar todos os chats do usuário (como comprador ou vendedor)
    const chats = await Chat.find({
      $or: [{ buyer_id: auth.userId }, { seller_id: auth.userId }],
      is_active: true,
    })
      .sort({ updated_at: -1 })
      .limit(100);

    // Serializar datas
    const serializedChats = chats.map((chat) => ({
      chat_id: chat.chat_id,
      listing_id: chat.listing_id,
      buyer_id: chat.buyer_id,
      seller_id: chat.seller_id,
      created_at: chat.created_at.toISOString(),
      updated_at: chat.updated_at.toISOString(),
      last_message_at: chat.last_message_at?.toISOString() || null,
      last_message_preview: chat.last_message_preview,
      buyer_unread_count: chat.buyer_unread_count,
      seller_unread_count: chat.seller_unread_count,
      is_active: chat.is_active,
      listing_cache: chat.listing_cache,
      buyer_cache: chat.buyer_cache,
      seller_cache: chat.seller_cache,
    }));

    return NextResponse.json(
      {
        success: true,
        chats: serializedChats,
        count: serializedChats.length,
      },
      { status: 200 },
    );
  } catch (error) {
    secureLogger.error("❌ Erro ao buscar chats", {
      error: error instanceof Error ? error.message : "Erro desconhecido",
      stack: error instanceof Error ? error.stack : undefined,
    });

    return NextResponse.json(
      { success: false, error: "Erro ao buscar chats" },
      { status: 500 },
    );
  }
}

/**
 * POST /api/chats
 * Cria um novo chat entre comprador e vendedor
 */
export async function POST(request: NextRequest) {
  try {
    const authResult = await requireAuth(request);
    if (authResult instanceof NextResponse) return authResult;
    const auth = authResult;

    const body = await request.json();
    const validationResult = createChatSchema.safeParse(body);

    if (!validationResult.success) {
      return NextResponse.json(
        {
          success: false,
          error: "Dados inválidos",
          details: validationResult.error.issues,
        },
        { status: 400 },
      );
    }

    const { listing_id, buyer_message } = validationResult.data;

    await connectMongoDB();

    // Buscar anúncio
    const listing = await getListingById(listing_id);
    if (!listing) {
      return NextResponse.json(
        { success: false, error: "Anúncio não encontrado" },
        { status: 404 },
      );
    }

    // Verificar se não é o próprio vendedor
    if (listing.seller_id === auth.userId) {
      return NextResponse.json(
        { success: false, error: "Você não pode criar um chat com você mesmo" },
        { status: 400 },
      );
    }

    // Verificar se anúncio está ativo
    if (listing.listing_status !== "active") {
      return NextResponse.json(
        { success: false, error: "Anúncio não está disponível para chat" },
        { status: 400 },
      );
    }

    // Gerar chat_id único
    const chat_id = `${listing_id}_${auth.userId}_${listing.seller_id}`;

    // Verificar se chat já existe
    let chat = await Chat.findOne({ chat_id });

    if (chat) {
      // Chat já existe, retornar
      return NextResponse.json(
        {
          success: true,
          chat: {
            chat_id: chat.chat_id,
            listing_id: chat.listing_id,
            buyer_id: chat.buyer_id,
            seller_id: chat.seller_id,
            created_at: chat.created_at.toISOString(),
            updated_at: chat.updated_at.toISOString(),
            last_message_at: chat.last_message_at?.toISOString() || null,
            last_message_preview: chat.last_message_preview,
            buyer_unread_count: chat.buyer_unread_count,
            seller_unread_count: chat.seller_unread_count,
            is_active: chat.is_active,
            listing_cache: chat.listing_cache,
            buyer_cache: chat.buyer_cache,
            seller_cache: chat.seller_cache,
          },
          already_exists: true,
        },
        { status: 200 },
      );
    }

    // Buscar dados do comprador
    const buyer = await getUserById(auth.userId);
    if (!buyer) {
      return NextResponse.json(
        { success: false, error: "Usuário não encontrado" },
        { status: 404 },
      );
    }

    const buyerCharacter = await getMainCharacter(auth.userId);

    // Buscar dados do vendedor
    const seller = await getUserById(listing.seller_id);
    if (!seller) {
      return NextResponse.json(
        { success: false, error: "Vendedor não encontrado" },
        { status: 404 },
      );
    }

    const sellerCharacter = await getMainCharacter(listing.seller_id);

    // Criar chat
    chat = new Chat({
      chat_id,
      listing_id,
      buyer_id: auth.userId,
      seller_id: listing.seller_id,
      listing_cache: {
        item_name: listing.item_name,
        item_image_url: null, // Imagem será obtida via item_id se necessário
        price_pix: listing.price_pix ? Number(listing.price_pix) : null,
        price_tibia_coins: listing.price_tibia_coins || null,
        price_gold_coins: listing.price_gold_coins
          ? Number(listing.price_gold_coins)
          : null,
        server_name: listing.server_name,
        listing_status: listing.listing_status,
      },
      buyer_cache: {
        user_id: buyer.user_id,
        username: buyer.username,
        character_name: buyerCharacter?.character_name || null,
      },
      seller_cache: {
        user_id: seller.user_id,
        username: seller.username,
        character_name: sellerCharacter?.character_name || null,
      },
    });

    await chat.save();

    // Se houver mensagem inicial, criar
    if (buyer_message && buyer_message.trim().length > 0) {
      const { Message } = await import("@/lib/mongodb/models/Message");
      const message = new Message({
        chat_id,
        sender_id: auth.userId,
        content: buyer_message.trim(),
        message_type: "text",
      });
      await message.save();

      // Atualizar chat
      chat.last_message_at = new Date();
      chat.last_message_preview = buyer_message.substring(0, 100);
      chat.seller_unread_count = 1;
      await chat.save();
    }

    return NextResponse.json(
      {
        success: true,
        chat: {
          chat_id: chat.chat_id,
          listing_id: chat.listing_id,
          buyer_id: chat.buyer_id,
          seller_id: chat.seller_id,
          created_at: chat.created_at.toISOString(),
          updated_at: chat.updated_at.toISOString(),
          last_message_at: chat.last_message_at?.toISOString() || null,
          last_message_preview: chat.last_message_preview,
          buyer_unread_count: chat.buyer_unread_count,
          seller_unread_count: chat.seller_unread_count,
          is_active: chat.is_active,
          listing_cache: chat.listing_cache,
          buyer_cache: chat.buyer_cache,
          seller_cache: chat.seller_cache,
        },
        already_exists: false,
      },
      { status: 201 },
    );
  } catch (error) {
    secureLogger.error("❌ Erro ao criar chat", {
      error: error instanceof Error ? error.message : "Erro desconhecido",
      stack: error instanceof Error ? error.stack : undefined,
    });

    return NextResponse.json(
      { success: false, error: "Erro ao criar chat" },
      { status: 500 },
    );
  }
}