const { DataTypes } = require('sequelize');
const { sequelize } = require('../config/database');

const GradeHistory = sequelize.define('grade_histories', {
  id: { type: DataTypes.UUID, defaultValue: DataTypes.UUIDV4, primaryKey: true },
  grade_id: { type: DataTypes.UUID, allowNull: false },
  student_id: { type: DataTypes.UUID, allowNull: false },
  old_score: { type: DataTypes.DECIMAL(5, 2) },
  new_score: { type: DataTypes.DECIMAL(5, 2) },
  changed_by: { type: DataTypes.UUID },
  change_reason: { type: DataTypes.TEXT },
  changed_at: { type: DataTypes.DATE, allowNull: false, defaultValue: DataTypes.NOW },
  created_at: { type: DataTypes.DATE, allowNull: false, defaultValue: DataTypes.NOW },
  updated_at: { type: DataTypes.DATE, allowNull: false, defaultValue: DataTypes.NOW },
}, {
  tableName: 'grade_histories',
  timestamps: true,
  underscored: true,
});

module.exports = GradeHistory;