import bcrypt from 'bcryptjs'
import { isValidPersonName, isValidUsername, NAME_RULE_MESSAGE, USERNAME_RULE_MESSAGE } from '~~/server/utils/username'
import { db } from '~/drizzle/db'
import { users } from '~/drizzle/schema'
import { eq } from 'drizzle-orm'
import { getRoleLevel, isRoleHigher, canManageUserRole } from '~~/server/utils/permissions'

export default defineEventHandler(async (event) => {
  // 检查认证和权限
  const user = event.context.user
  if (!user || !['ADMIN', 'SUPER_ADMIN'].includes(user.role)) {
    throw createError({
      statusCode: 403,
      message: '没有权限访问'
    })
  }

  const body = await readBody(event)

  // 验证必填字段
  if (!body.name || !body.username || !body.password) {
    throw createError({
      statusCode: 400,
      message: '姓名、账号名和密码不能为空'
    })
  }

  // 账号名必须是纯中文（唯一例外是管理员账号 admin —— 规则见 utils/username.ts）
  if (!isValidPersonName(body.name, body.username) || !isValidUsername(body.username)) {
    throw createError({
      statusCode: 400,
      message: NAME_RULE_MESSAGE + '；' + USERNAME_RULE_MESSAGE
    })
  }

  try {
    // 检查用户名是否已存在
    const existingUserResult = await db
      .select()
      .from(users)
      .where(eq(users.username, body.username))
      .limit(1)
    const existingUser = existingUserResult[0]

    if (existingUser) {
      throw createError({
        statusCode: 400,
        message: '账号名已存在'
      })
    }

    // 加密密码
    const hashedPassword = await bcrypt.hash(body.password, 10)

    // 角色权限控制（统一使用 canManageUserRole 数值化级别检查）
    let validRole = 'USER'
    const requestedRole = body.role
    if (requestedRole) {
      if (!canManageUserRole(user, requestedRole)) {
        const currentLevel = getRoleLevel(user.role)
        const targetLevel = getRoleLevel(requestedRole)
        throw createError({
          statusCode: 403,
          message: isRoleHigher(requestedRole, user.role) || currentLevel <= targetLevel
            ? `权限不足：${user.role} 无法创建级别高于或等于自身的角色（${requestedRole}）`
            : `没有权限创建 ${requestedRole} 角色的用户`
        })
      }
      validRole = requestedRole
    }

    // 状态验证
    let validStatus = 'active'
    if (body.status && ['active', 'withdrawn', 'graduate'].includes(body.status)) {
      validStatus = body.status
    }

    // 创建用户
    const newUserResult = await db
      .insert(users)
      .values({
        name: body.name,
        username: body.username,
        password: hashedPassword,
        role: validRole,
        status: validStatus as 'active' | 'withdrawn' | 'graduate',
        grade: body.grade,
        class: body.class
      })
      .returning({
        id: users.id,
        name: users.name,
        username: users.username,
        role: users.role,
        status: users.status,
        grade: users.grade,
        class: users.class,
        createdAt: users.createdAt,
        updatedAt: users.updatedAt
      })
    const newUser = newUserResult[0]

    // 清除相关缓存
    try {
      const { cache } = await import('~~/server/utils/cache-helpers')
      await cache.deletePattern('songs:*')
      await cache.deletePattern('stats:*')
      console.log('[Cache] 歌曲和统计缓存已清除（用户创建）')
    } catch (cacheError) {
      console.warn('[Cache] 清除缓存失败:', cacheError)
    }

    return {
      success: true,
      user: newUser,
      message: '用户创建成功'
    }
  } catch (error) {
    console.error('创建用户失败:', error)
    throw createError({
      statusCode: 500,
      message: '创建用户失败'
    })
  }
})