import { NextResponse } from "next/server";
import { db } from "@/lib/db";
import { user } from "@/lib/db/schema";
import { eq, isNull, or, sql } from "drizzle-orm";
import { auth } from "@/app/(auth)/auth";

// 获取所有部门列表
export async function GET() {
  try {
    const session = await auth();
    
    if (!session?.user?.id) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    // 检查是否为管理员
    const currentUser = await db.query.user.findFirst({
      where: eq(user.id, session.user.id),
    });

    if (currentUser?.role !== "admin") {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }

    // 获取所有不重复的部门列表
    const departments = await db
      .selectDistinct({ department: user.department })
      .from(user)
      .where(sql`${user.department} IS NOT NULL AND ${user.department} != ''`)
      .orderBy(user.department);

    return NextResponse.json({
      departments: departments.map(d => d.department).filter(Boolean),
    });
  } catch (error) {
    console.error("[Batch Limit API] Error:", error);
    return NextResponse.json({ error: "获取部门列表失败" }, { status: 500 });
  }
}

// 批量设置出图限制
export async function POST(request: Request) {
  try {
    const session = await auth();
    
    if (!session?.user?.id) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    // 检查是否为管理员
    const currentUser = await db.query.user.findFirst({
      where: eq(user.id, session.user.id),
    });

    if (currentUser?.role !== "admin") {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }

    const body = await request.json();
    const { type, limit, department } = body;

    // limit 为 null 表示无限制，为数字表示限制张数
    const limitValue = limit === null || limit === "" || limit === undefined ? null : parseInt(limit, 10);

    let updatedCount = 0;

    if (type === "all") {
      // 批量设置所有用户
      const result = await db
        .update(user)
        .set({ monthlyImageLimit: limitValue });
      
      // 获取更新的用户数
      const allUsers = await db.select({ id: user.id }).from(user);
      updatedCount = allUsers.length;
      
      console.log(`[Batch Limit] 批量设置所有用户限额: ${limitValue ?? "无限制"}, 影响 ${updatedCount} 个用户`);
    } else if (type === "department" && department) {
      // 按部门批量设置
      await db
        .update(user)
        .set({ monthlyImageLimit: limitValue })
        .where(eq(user.department, department));
      
      // 获取更新的用户数
      const deptUsers = await db.select({ id: user.id }).from(user).where(eq(user.department, department));
      updatedCount = deptUsers.length;
      
      console.log(`[Batch Limit] 批量设置部门 "${department}" 限额: ${limitValue ?? "无限制"}, 影响 ${updatedCount} 个用户`);
    } else if (type === "no_department") {
      // 设置无部门用户
      await db
        .update(user)
        .set({ monthlyImageLimit: limitValue })
        .where(or(isNull(user.department), eq(user.department, "")));
      
      // 获取更新的用户数
      const noDeptUsers = await db
        .select({ id: user.id })
        .from(user)
        .where(or(isNull(user.department), eq(user.department, "")));
      updatedCount = noDeptUsers.length;
      
      console.log(`[Batch Limit] 批量设置无部门用户限额: ${limitValue ?? "无限制"}, 影响 ${updatedCount} 个用户`);
    } else {
      return NextResponse.json({ error: "无效的操作类型" }, { status: 400 });
    }

    return NextResponse.json({
      success: true,
      message: `成功更新 ${updatedCount} 个用户的出图限额`,
      updatedCount,
      limit: limitValue,
    });
  } catch (error) {
    console.error("[Batch Limit API] Error:", error);
    return NextResponse.json({ error: "批量设置失败" }, { status: 500 });
  }
}