const { DataTypes } = require('sequelize')
const BaseModel = require('./BaseModel')
const { sequelize } = require('../config/database-simple')

/**
 * 电子围栏模型
 */
class ElectronicFence extends BaseModel {
  static init(sequelize) {
    return super.init({
      id: {
        type: DataTypes.INTEGER,
        primaryKey: true,
        autoIncrement: true,
        comment: '围栏ID'
      },
      name: {
        type: DataTypes.STRING(100),
        allowNull: false,
        comment: '围栏名称'
      },
      type: {
        type: DataTypes.ENUM('collector', 'grazing', 'safety'),
        allowNull: false,
        defaultValue: 'collector',
        comment: '围栏类型: collector-采集器电子围栏, grazing-放牧围栏, safety-安全围栏'
      },
      description: {
        type: DataTypes.TEXT,
        allowNull: true,
        comment: '围栏描述'
      },
      coordinates: {
        type: DataTypes.JSON,
        allowNull: false,
        comment: '围栏坐标点数组'
      },
      center_lng: {
        type: DataTypes.DECIMAL(10, 7),
        allowNull: false,
        comment: '围栏中心经度'
      },
      center_lat: {
        type: DataTypes.DECIMAL(10, 7),
        allowNull: false,
        comment: '围栏中心纬度'
      },
      area: {
        type: DataTypes.DECIMAL(10, 4),
        allowNull: true,
        comment: '围栏面积(平方米)'
      },
      grazing_status: {
        type: DataTypes.ENUM('grazing', 'not_grazing'),
        allowNull: false,
        defaultValue: 'not_grazing',
        comment: '放牧状态: grazing-放牧中, not_grazing-未放牧'
      },
      inside_count: {
        type: DataTypes.INTEGER,
        allowNull: false,
        defaultValue: 0,
        comment: '安全区域内动物数量'
      },
      outside_count: {
        type: DataTypes.INTEGER,
        allowNull: false,
        defaultValue: 0,
        comment: '安全区域外动物数量'
      },
      is_active: {
        type: DataTypes.BOOLEAN,
        allowNull: false,
        defaultValue: true,
        comment: '是否启用'
      },
      farm_id: {
        type: DataTypes.INTEGER,
        allowNull: true,
        comment: '关联农场ID'
      },
      created_by: {
        type: DataTypes.INTEGER,
        allowNull: true,
        comment: '创建人ID'
      },
      updated_by: {
        type: DataTypes.INTEGER,
        allowNull: true,
        comment: '更新人ID'
      }
    }, {
      sequelize,
      modelName: 'ElectronicFence',
      tableName: 'electronic_fences',
      timestamps: true,
      createdAt: 'created_at',
      updatedAt: 'updated_at',
      comment: '电子围栏表',
      indexes: [
        {
          name: 'idx_fence_name',
          fields: ['name']
        },
        {
          name: 'idx_fence_type',
          fields: ['type']
        },
        {
          name: 'idx_fence_center',
          fields: ['center_lng', 'center_lat']
        },
        {
          name: 'idx_fence_active',
          fields: ['is_active']
        }
      ]
    })
  }

  /**
   * 定义关联关系
   */
  static associate(models) {
    // 围栏与农场关联（可选）
    this.belongsTo(models.Farm, {
      foreignKey: 'farm_id',
      as: 'farm'
    })
  }

  /**
   * 获取围栏类型文本
   */
  getTypeText() {
    const typeMap = {
      'collector': '采集器电子围栏',
      'grazing': '放牧围栏',
      'safety': '安全围栏'
    }
    return typeMap[this.type] || '未知类型'
  }

  /**
   * 获取放牧状态文本
   */
  getGrazingStatusText() {
    const statusMap = {
      'grazing': '放牧中',
      'not_grazing': '未放牧'
    }
    return statusMap[this.grazing_status] || '未知状态'
  }

  /**
   * 计算围栏面积（简化计算）
   */
  calculateArea() {
    if (!this.coordinates || this.coordinates.length < 3) {
      return 0
    }

    // 使用Shoelace公式计算多边形面积
    let area = 0
    const coords = this.coordinates
    
    for (let i = 0; i < coords.length; i++) {
      const j = (i + 1) % coords.length
      area += coords[i].lng * coords[j].lat
      area -= coords[j].lng * coords[i].lat
    }
    
    // 转换为平方米（粗略计算）
    return Math.abs(area) * 111000 * 111000 / 2
  }

  /**
   * 计算围栏中心点
   */
  calculateCenter() {
    if (!this.coordinates || this.coordinates.length === 0) {
      return { lng: 0, lat: 0 }
    }

    let lngSum = 0
    let latSum = 0
    
    this.coordinates.forEach(coord => {
      lngSum += coord.lng
      latSum += coord.lat
    })
    
    return {
      lng: lngSum / this.coordinates.length,
      lat: latSum / this.coordinates.length
    }
  }

  /**
   * 检查点是否在围栏内
   */
  isPointInside(lng, lat) {
    if (!this.coordinates || this.coordinates.length < 3) {
      return false
    }

    let inside = false
    const coords = this.coordinates
    
    for (let i = 0, j = coords.length - 1; i < coords.length; j = i++) {
      if (((coords[i].lat > lat) !== (coords[j].lat > lat)) &&
          (lng < (coords[j].lng - coords[i].lng) * (lat - coords[i].lat) / (coords[j].lat - coords[i].lat) + coords[i].lng)) {
        inside = !inside
      }
    }
    
    return inside
  }

  /**
   * 转换为前端格式
   */
  toFrontendFormat() {
    return {
      id: this.id,
      name: this.name,
      type: this.getTypeText(),
      description: this.description,
      coordinates: this.coordinates,
      center: {
        lng: this.center_lng,
        lat: this.center_lat
      },
      area: this.area,
      grazingStatus: this.getGrazingStatusText(),
      insideCount: this.inside_count,
      outsideCount: this.outside_count,
      isActive: this.is_active,
      createdAt: this.created_at,
      updatedAt: this.updated_at
    }
  }
}

// 初始化模型
ElectronicFence.init(sequelize)

module.exports = ElectronicFence