import { prisma } from "@/lib/prisma";
import { getServerSession } from "next-auth";
import { authOptions } from "@/lib/auth";
import { NextResponse } from "next/server";
import { rewardPoints } from "@/lib/points-reward";

export async function GET(req: Request) {
  const { searchParams } = new URL(req.url);
  const toolId = searchParams.get("toolId");
  const skillId = searchParams.get("skillId");
  const parentId = searchParams.get("parentId");
  const page = parseInt(searchParams.get("page") || "1", 10);
  const pageSize = parseInt(searchParams.get("pageSize") || "20", 10);

  if (!toolId && !skillId) {
    return NextResponse.json({ error: "必须提供 toolId 或 skillId" }, { status: 400 });
  }

  const where: any = { status: "ACTIVE" };
  if (toolId) where.toolId = parseInt(toolId);
  if (skillId) where.skillId = parseInt(skillId);
  if (parentId) where.parentId = parseInt(parentId);
  else where.parentId = null;

  const [comments, totalCount] = await Promise.all([
    prisma.comment.findMany({
      where,
      include: {
        user: { select: { id: true, name: true, email: true, avatarUrl: true, level: true, points: true } },
        likes: { select: { userId: true } },
        replies: {
          where: { status: "ACTIVE" },
          include: {
            user: { select: { id: true, name: true, email: true, avatarUrl: true, level: true, points: true } },
            likes: { select: { userId: true } },
          },
          orderBy: { createdAt: "asc" },
          take: 5,
        },
        _count: { select: { replies: true } },
      },
      orderBy: [
        { isPinned: "desc" },
        { createdAt: "desc" },
      ],
      skip: (page - 1) * pageSize,
      take: pageSize,
    }),
    prisma.comment.count({ where }),
  ]);

  const session = await getServerSession(authOptions);
  const currentUserId = session?.user?.id ? parseInt(session.user.id) : null;

  const formatted = comments.map((c: any) => ({
    id: c.id,
    content: c.content,
    rating: c.rating,
    likeCount: c.likeCount,
    isPinned: c.isPinned,
    createdAt: c.createdAt,
    updatedAt: c.updatedAt,
    replyCount: c._count.replies,
    liked: currentUserId ? c.likes.some((l: any) => l.userId === currentUserId) : false,
    user: {
      id: c.user.id,
      name: c.user.name || c.user.email.split("@")[0],
      avatarUrl: c.user.avatarUrl,
      level: c.user.level,
      points: c.user.points,
    },
    replies: c.replies.map((r: any) => ({
      id: r.id,
      content: r.content,
      likeCount: r.likeCount,
      createdAt: r.createdAt,
      liked: currentUserId ? r.likes.some((l: any) => l.userId === currentUserId) : false,
      user: {
        id: r.user.id,
        name: r.user.name || r.user.email.split("@")[0],
        avatarUrl: r.user.avatarUrl,
        level: r.user.level,
        points: r.user.points,
      },
    })),
  }));

  return NextResponse.json({ comments: formatted, totalCount, page, pageSize });
}

export async function POST(req: Request) {
  const session = await getServerSession(authOptions);
  if (!session?.user?.id) {
    return NextResponse.json({ error: "请先登录" }, { status: 401 });
  }

  const body = await req.json();
  const { toolSlug, skillSlug, content, rating, parentId } = body;
  const userId = parseInt(session.user.id);

  if (!content || !content.trim()) {
    return NextResponse.json({ error: "评论内容不能为空" }, { status: 400 });
  }
  if (content.trim().length > 2000) {
    return NextResponse.json({ error: "评论内容不能超过2000个字符" }, { status: 400 });
  }

  let toolId: number | undefined;
  let skillId: number | undefined;

  if (toolSlug) {
    const tool = await prisma.tool.findUnique({ where: { slug: toolSlug } });
    if (!tool) return NextResponse.json({ error: "工具不存在" }, { status: 404 });
    toolId = tool.id;
  } else if (skillSlug) {
    const skill = await prisma.skill.findUnique({ where: { slug: skillSlug } });
    if (!skill) return NextResponse.json({ error: "技能不存在" }, { status: 404 });
    skillId = skill.id;
  } else {
    return NextResponse.json({ error: "必须提供 toolSlug 或 skillSlug" }, { status: 400 });
  }

  if (!parentId && rating && (rating < 1 || rating > 5)) {
    return NextResponse.json({ error: "评分必须为1-5" }, { status: 400 });
  }

  const comment = await prisma.$transaction(async (tx) => {
    const newComment = await tx.comment.create({
      data: {
        userId,
        toolId,
        skillId,
        parentId: parentId || null,
        content: content.trim(),
        rating: parentId ? null : rating || null,
      },
      include: {
        user: { select: { id: true, name: true, email: true, avatarUrl: true, level: true, points: true } },
      },
    });

    if (!parentId) {
      if (toolId) {
        await tx.tool.update({
          where: { id: toolId },
          data: { commentCount: { increment: 1 } },
        });
      }
      if (skillId) {
        await tx.skill.update({
          where: { id: skillId },
          data: { commentCount: { increment: 1 } },
        });
      }
    }

    const parentComment = parentId
      ? await tx.comment.findUnique({ where: { id: parentId }, select: { userId: true } })
      : null;

    if (parentComment && parentComment.userId !== userId) {
      const replyTo = await tx.user.findUnique({
        where: { id: parentId ? (await tx.comment.findUnique({ where: { id: parentId } }))?.userId : undefined },
        select: { id: true, name: true },
      });
      if (replyTo) {
        await tx.notification.create({
          data: {
            userId: replyTo.id,
            type: "COMMENT_REPLY",
            title: `${session.user.name || "用户"} 回复了你的评论`,
            content: content.trim().slice(0, 100),
            link: toolSlug ? `/tools/${toolSlug}` : `/skills/${skillSlug}`,
          },
        });
      }
    }

    return newComment;
  });

  if (!parentId) {
    await rewardPoints(userId, "comment", `评论${toolSlug || skillSlug}`, toolSlug ? "tool" : "skill", toolId || skillId);
  }

  const formatted = {
    id: comment.id,
    content: comment.content,
    rating: comment.rating,
    likeCount: 0,
    isPinned: comment.isPinned,
    createdAt: comment.createdAt,
    updatedAt: comment.updatedAt,
    replyCount: 0,
    liked: false,
    user: {
      id: comment.user.id,
      name: comment.user.name || comment.user.email.split("@")[0],
      avatarUrl: comment.user.avatarUrl,
      level: comment.user.level,
      points: comment.user.points,
    },
  };

  return NextResponse.json(formatted, { status: 201 });
}