const mongoose = require('mongoose')
const { Schema } = mongoose
const bcrypt = require('bcryptjs')

/**
 * 管理员模型
 */
const AdminSchema = new Schema({
  // 登录信息
  username: {
    type: String,
    required: true,
    unique: true,
    trim: true,
    lowercase: true,
    minlength: 3,
    maxlength: 30
  },
  password: {
    type: String,
    required: true,
    minlength: 6
  },
  email: {
    type: String,
    trim: true,
    lowercase: true
  },
  
  // 基本信息
  realName: String,
  phone: String,
  avatar: String,
  
  // 角色
  role: {
    type: String,
    enum: ['super_admin', 'content_manager', 'shop_manager', 'viewer'],
    default: 'viewer'
  },
  
  // 权限
  permissions: [{
    type: String
  }],
  
  // 状态
  status: {
    type: String,
    enum: ['active', 'inactive', 'suspended'],
    default: 'active'
  },
  
  // 登录信息
  lastLogin: Date,
  lastLoginIp: String,
  loginCount: {
    type: Number,
    default: 0
  },
  
  // 时间戳
  createdAt: {
    type: Date,
    default: Date.now
  },
  updatedAt: {
    type: Date,
    default: Date.now
  }
}, {
  timestamps: true,
  toJSON: { virtuals: true },
  toObject: { virtuals: true }
})

// 索引（username 已通过 unique: true 自动创建索引）
AdminSchema.index({ role: 1 })

// 中间件：保存前加密密码
AdminSchema.pre('save', async function(next) {
  if (!this.isModified('password')) {
    return next()
  }
  
  try {
    const salt = await bcrypt.genSalt(10)
    this.password = await bcrypt.hash(this.password, salt)
    next()
  } catch (error) {
    next(error)
  }
})

// 实例方法：验证密码
AdminSchema.methods.validatePassword = async function(password) {
  return bcrypt.compare(password, this.password)
}

// 实例方法：检查权限
AdminSchema.methods.hasPermission = function(permission) {
  if (this.permissions.includes('*')) return true
  return this.permissions.includes(permission)
}

// 静态方法：根据角色获取权限
AdminSchema.statics.getPermissionsByRole = function(role) {
  const permissionMap = {
    super_admin: ['*'],
    content_manager: [
      'knowledge:read', 'knowledge:write', 'knowledge:delete',
      'gallery:read', 'gallery:approve', 'gallery:delete',
      'users:read'
    ],
    shop_manager: [
      'shop:read', 'shop:write', 'shop:delete',
      'orders:read', 'orders:process', 'orders:refund',
      'users:read'
    ],
    viewer: [
      'dashboard:read',
      'analytics:read',
      'users:read'
    ]
  }
  
  return permissionMap[role] || []
}

module.exports = mongoose.model('Admin', AdminSchema)