import fs from 'fs'
import path from 'path'

// 获取角色配置文件路径
const getRolesFilePath = () => {
  return path.resolve(process.cwd(), 'server', 'config', 'roles.json')
}

// 获取当前角色配置
export let ROLES = {}
try {
  const filePath = getRolesFilePath()
  if (fs.existsSync(filePath)) {
    const data = fs.readFileSync(filePath, 'utf-8')
    ROLES = JSON.parse(data)
  }
} catch (err) {
  console.error('Failed to load roles.json:', err)
}

// 确保角色对象存在
if (!ROLES.USER) {
  ROLES = {
    USER: { displayName: '学生（普通用户）', pages: [], canAccessAdmin: false },
    SONG_ADMIN: { displayName: '工作人员', pages: ['schedule', 'songs', 'print'], canAccessAdmin: true },
    VICE_MINISTER: { displayName: '副部', pages: ['overview', 'schedule', 'songs', 'print', 'users'], canAccessAdmin: true },
    ADMIN: { displayName: '部长', pages: ['overview', 'schedule', 'songs', 'print', 'users', 'data-analysis', 'notifications', 'playtimes', 'semesters'], canAccessAdmin: true },
    RESIDENT: { displayName: '常驻', pages: ['schedule', 'songs', 'print'], canAccessAdmin: true },
    SUPER_ADMIN: { displayName: '技术运维', pages: ['overview', 'workflow-tutorial', 'schedule', 'songs', 'print', 'users', 'roles', 'blacklist', 'api-keys', 'notifications', 'smtp-config', 'playtimes', 'request-times', 'semesters', 'settings', 'site-config', 'database', 'data-analysis'], canAccessAdmin: true }
  }
}

// 保存角色配置
export function saveRolesConfig(newRoles) {
  try {
    ROLES = newRoles
    const filePath = getRolesFilePath()
    const dir = path.dirname(filePath)
    if (!fs.existsSync(dir)) {
      fs.mkdirSync(dir, { recursive: true })
    }
    fs.writeFileSync(filePath, JSON.stringify(ROLES, null, 2), 'utf-8')
    return true
  } catch (err) {
    console.error('Failed to save roles.json:', err)
    return false
  }
}

// 检查用户是否可以访问后台
function canAccessAdmin(user) {
  if (!user || !user.role) return false

  const roleConfig = ROLES[user.role]
  if (!roleConfig) return false

  return roleConfig.canAccessAdmin
}

// 检查用户是否可以访问指定页面
function canAccessPage(user, page) {
  if (!user || !user.role) return false

  // 超级管理员可以访问所有页面
  if (user.role === 'SUPER_ADMIN') return true

  const roleConfig = ROLES[user.role]
  if (!roleConfig) return false

  return roleConfig.pages.includes(page)
}

// 获取用户可访问的页面列表
function getUserPages(user) {
  if (!user || !user.role) return []

  const roleConfig = ROLES[user.role]
  if (!roleConfig) return []

  return roleConfig.pages
}

// 获取角色信息
function getRoleInfo(roleName) {
  return ROLES[roleName] || null
}

const ROLE_LEVELS = {
  SUPER_ADMIN: 100,
  ADMIN: 80,
  MINISTER: 80,
  VICE_MINISTER: 70,
  SONG_ADMIN: 60,
  STAFF: 60,
  RESIDENT: 50,
  TEACHER: 40,
  USER: 10
}

export function getRoleLevel(roleName) {
  if (!roleName) return 0
  const upperRole = String(roleName).toUpperCase()
  return ROLE_LEVELS[upperRole] ?? 0
}

export function isRoleHigherOrEqual(currentRole, targetRole) {
  return getRoleLevel(currentRole) >= getRoleLevel(targetRole)
}

export function isRoleHigher(currentRole, targetRole) {
  return getRoleLevel(currentRole) > getRoleLevel(targetRole)
}

function canResetPasswordFor(currentUser, targetUser) {
  if (!currentUser || !currentUser.role || !targetUser) return false

  const currentLevel = getRoleLevel(currentUser.role)
  const targetLevel = getRoleLevel(targetUser.role)

  if (currentUser.role === 'SUPER_ADMIN') {
    return true
  }

  if (currentUser.role === 'ADMIN' || currentUser.role === 'MINISTER') {
    return targetLevel <= getRoleLevel('USER')
  }

  return false
}

function canChangeRoleOf(currentUser, targetUser, newRole) {
  if (!currentUser || !currentUser.role || !targetUser) return false

  const currentLevel = getRoleLevel(currentUser.role)
  const targetLevel = getRoleLevel(targetUser.role)
  const newRoleLevel = getRoleLevel(newRole)

  if (String(currentUser.id) === String(targetUser.id)) {
    return false
  }

  if (currentUser.role === 'SUPER_ADMIN') {
    if (targetUser.id === 1) return false
    return newRoleLevel <= currentLevel
  }

  if (currentLevel < targetLevel) {
    return false
  }

  if (newRoleLevel >= currentLevel) {
    return false
  }

  return true
}

function canDeleteUser(currentUser, targetUser) {
  if (!currentUser || !currentUser.role || !targetUser) return false

  if (String(currentUser.id) === String(targetUser.id)) {
    return false
  }

  if (targetUser.id === 1) {
    return false
  }

  const currentLevel = getRoleLevel(currentUser.role)
  const targetLevel = getRoleLevel(targetUser.role)

  return currentLevel > targetLevel
}

function canManageUserRole(currentUser, targetRole) {
  if (!currentUser || !currentUser.role) return false

  if (currentUser.role === 'SUPER_ADMIN') {
    return Object.keys(ROLES).includes(targetRole) && targetRole !== 'SUPER_ADMIN'
  }

  const currentLevel = getRoleLevel(currentUser.role)
  const targetLevel = getRoleLevel(targetRole)
  return targetLevel < currentLevel
}

// 导出所有函数和常量
export {
  canAccessAdmin,
  canAccessPage,
  getUserPages,
  getRoleInfo,
  canManageUserRole,
  canResetPasswordFor,
  canChangeRoleOf,
  canDeleteUser
}