/**
 * 贷款合同模型
 * @file LoanContract.js
 * @description 银行系统贷款合同数据模型
 */
const { DataTypes } = require('sequelize');
const BaseModel = require('./BaseModel');

class LoanContract extends BaseModel {
  /**
   * 获取合同状态文本
   * @returns {String} 状态文本
   */
  getStatusText() {
    const statusMap = {
      active: '已放款',
      pending: '待放款',
      completed: '已完成',
      defaulted: '违约',
      cancelled: '已取消'
    };
    return statusMap[this.status] || this.status;
  }

  /**
   * 获取合同类型文本
   * @returns {String} 类型文本
   */
  getTypeText() {
    const typeMap = {
      livestock_collateral: '畜禽活体抵押',
      farmer_loan: '惠农贷',
      business_loan: '商业贷款',
      personal_loan: '个人贷款'
    };
    return typeMap[this.type] || this.type;
  }

  /**
   * 格式化合同金额
   * @returns {String} 格式化后的金额
   */
  getFormattedAmount() {
    return `${this.amount.toFixed(2)}元`;
  }

  /**
   * 计算剩余还款金额
   * @returns {Number} 剩余金额
   */
  getRemainingAmount() {
    return this.amount - (this.paidAmount || 0);
  }

  /**
   * 计算还款进度百分比
   * @returns {Number} 进度百分比
   */
  getRepaymentProgress() {
    if (this.amount <= 0) return 0;
    return Math.round(((this.paidAmount || 0) / this.amount) * 100);
  }
}

// 初始化LoanContract模型
LoanContract.init({
  id: {
    type: DataTypes.INTEGER,
    primaryKey: true,
    autoIncrement: true
  },
  contractNumber: {
    type: DataTypes.STRING(50),
    allowNull: false,
    unique: true,
    comment: '合同编号'
  },
  applicationNumber: {
    type: DataTypes.STRING(50),
    allowNull: false,
    comment: '申请单号'
  },
  productName: {
    type: DataTypes.STRING(200),
    allowNull: false,
    comment: '贷款产品名称'
  },
  farmerName: {
    type: DataTypes.STRING(100),
    allowNull: false,
    comment: '申请养殖户姓名'
  },
  borrowerName: {
    type: DataTypes.STRING(100),
    allowNull: false,
    comment: '贷款人姓名'
  },
  borrowerIdNumber: {
    type: DataTypes.STRING(20),
    allowNull: false,
    comment: '贷款人身份证号'
  },
  assetType: {
    type: DataTypes.STRING(50),
    allowNull: false,
    comment: '生资种类'
  },
  applicationQuantity: {
    type: DataTypes.STRING(100),
    allowNull: false,
    comment: '申请数量'
  },
  amount: {
    type: DataTypes.DECIMAL(15, 2),
    allowNull: false,
    comment: '合同金额'
  },
  paidAmount: {
    type: DataTypes.DECIMAL(15, 2),
    allowNull: false,
    defaultValue: 0,
    comment: '已还款金额'
  },
  status: {
    type: DataTypes.ENUM(
      'active',
      'pending', 
      'completed',
      'defaulted',
      'cancelled'
    ),
    allowNull: false,
    defaultValue: 'pending',
    comment: '合同状态'
  },
  type: {
    type: DataTypes.ENUM(
      'livestock_collateral',
      'farmer_loan',
      'business_loan',
      'personal_loan'
    ),
    allowNull: false,
    comment: '合同类型'
  },
  term: {
    type: DataTypes.INTEGER,
    allowNull: false,
    comment: '合同期限（月）'
  },
  interestRate: {
    type: DataTypes.DECIMAL(5, 2),
    allowNull: false,
    comment: '利率'
  },
  phone: {
    type: DataTypes.STRING(20),
    allowNull: false,
    comment: '联系电话'
  },
  purpose: {
    type: DataTypes.TEXT,
    allowNull: true,
    comment: '贷款用途'
  },
  remark: {
    type: DataTypes.TEXT,
    allowNull: true,
    comment: '备注'
  },
  contractTime: {
    type: DataTypes.DATE,
    allowNull: false,
    defaultValue: DataTypes.NOW,
    comment: '合同签订时间'
  },
  disbursementTime: {
    type: DataTypes.DATE,
    allowNull: true,
    comment: '放款时间'
  },
  maturityTime: {
    type: DataTypes.DATE,
    allowNull: true,
    comment: '到期时间'
  },
  completedTime: {
    type: DataTypes.DATE,
    allowNull: true,
    comment: '完成时间'
  },
  createdBy: {
    type: DataTypes.INTEGER,
    allowNull: true,
    comment: '创建人ID',
    references: {
      model: 'bank_users',
      key: 'id'
    }
  },
  updatedBy: {
    type: DataTypes.INTEGER,
    allowNull: true,
    comment: '更新人ID',
    references: {
      model: 'bank_users',
      key: 'id'
    }
  }
}, {
  sequelize: require('../config/database').sequelize,
  modelName: 'LoanContract',
  tableName: 'bank_loan_contracts',
  timestamps: true,
  createdAt: 'createdAt',
  updatedAt: 'updatedAt',
  hooks: {
    beforeCreate: (contract) => {
      // 生成合同编号
      if (!contract.contractNumber) {
        const now = new Date();
        const timestamp = now.getFullYear().toString() +
          (now.getMonth() + 1).toString().padStart(2, '0') +
          now.getDate().toString().padStart(2, '0') +
          now.getHours().toString().padStart(2, '0') +
          now.getMinutes().toString().padStart(2, '0') +
          now.getSeconds().toString().padStart(2, '0');
        const random = Math.floor(Math.random() * 1000).toString().padStart(3, '0');
        contract.contractNumber = 'HT' + timestamp + random;
      }
    }
  }
});

module.exports = LoanContract;