import { prisma } from "@/lib/prisma";
import { NextResponse } from "next/server";
import { getLevelInfo } from "@/lib/level-config";

export async function GET(_req: Request, { params }: { params: { id: string } }) {
  try {
    const userId = parseInt(params.id);
    if (isNaN(userId)) {
      return NextResponse.json({ error: "无效的用户ID" }, { status: 400 });
    }

    const user = await prisma.user.findUnique({
      where: { id: userId },
      select: {
        id: true,
        name: true,
        email: true,
        bio: true,
        avatarUrl: true,
        points: true,
        level: true,
        role: true,
        isBot: true,
        createdAt: true,
        _count: {
          select: {
            forumTopics: true,
            forumPosts: true,
            comments: true,
            favorites: true,
            topicLikes: true,
            postLikes: true,
            topicBookmarks: true,
            categoryFollows: true,
          },
        },
        achievements: {
          include: {
            achievement: { select: { key: true, name: true, icon: true, tier: true } },
          },
          orderBy: { unlockedAt: "desc" },
          take: 6,
        },
      },
    });

    if (!user) {
      return NextResponse.json({ error: "用户不存在" }, { status: 404 });
    }

    const [bestAnswerCount, totalLikesReceived, checkInStreak, followCount] = await Promise.all([
      prisma.forumPost.count({
        where: { userId, isAnswer: true },
      }),
      prisma.forumPost.aggregate({
        where: { userId },
        _sum: { likeCount: true },
      }),
      prisma.forumCheckIn.findFirst({
        where: { userId },
        orderBy: { checkInDate: "desc" },
        select: { streak: true, checkInDate: true },
      }),
      prisma.forumCategoryFollow.count({
        where: { userId },
      }),
    ]);

    const levelInfo = getLevelInfo(user.points);

    return NextResponse.json({
      id: user.id,
      name: user.name,
      email: user.email,
      bio: user.bio,
      avatarUrl: user.avatarUrl,
      points: user.points,
      level: user.level,
      role: user.role,
      isBot: user.isBot,
      createdAt: user.createdAt,
      levelInfo,
      stats: {
        topicCount: user._count.forumTopics,
        postCount: user._count.forumPosts,
        commentCount: user._count.comments,
        favoriteCount: user._count.favorites,
        bookmarkCount: user._count.topicBookmarks,
        followedCategoryCount: followCount,
        bestAnswerCount,
        likesReceived: totalLikesReceived._sum.likeCount || 0,
        checkInStreak: checkInStreak?.streak || 0,
        lastCheckInDate: checkInStreak?.checkInDate || null,
      },
      achievements: user.achievements.map(a => ({
        key: a.achievement.key,
        name: a.achievement.name,
        icon: a.achievement.icon,
        tier: a.achievement.tier,
        progress: a.progress,
        unlockedAt: a.unlockedAt,
      })),
    });
  } catch (error: unknown) {
    const err = error as { message?: string };
    return NextResponse.json({ error: err.message || "获取用户资料失败" }, { status: 500 });
  }
}