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

const VocabMapping = sequelize.define('VocabMapping', {
    mapping_id: {
      type: DataTypes.UUID,
      defaultValue: DataTypes.UUIDV4,
      primaryKey: true,
      comment: 'Unique identifier for curriculum mapping'
    },
    vocab_id: {
      type: DataTypes.UUID,
      allowNull: false,
      references: {
        model: 'vocab',
        key: 'vocab_id'
      },
      onDelete: 'CASCADE',
      comment: 'Reference to vocabulary entry'
    },
    book_id: {
      type: DataTypes.STRING(100),
      allowNull: false,
      comment: 'Book/curriculum identifier (e.g., global-success-1)'
    },
    grade: {
      type: DataTypes.INTEGER,
      allowNull: false,
      comment: 'Grade level'
    },
    unit: {
      type: DataTypes.INTEGER,
      comment: 'Unit number in the book'
    },
    lesson: {
      type: DataTypes.INTEGER,
      comment: 'Lesson number in the unit'
    },
    form_key: {
      type: DataTypes.STRING(50),
      comment: 'Which form to use (v1, v_s_es, v_ing, v2, v3, etc.)'
    },
    context_note: {
      type: DataTypes.TEXT,
      comment: 'Additional context for this mapping'
    },
    created_at: {
      type: DataTypes.DATE,
      defaultValue: DataTypes.NOW
    }
  }, {
    tableName: 'vocab_mapping',
    timestamps: true,
    createdAt: 'created_at',
    updatedAt: false,
    indexes: [
      {
        name: 'idx_vocab_mapping_vocab',
        fields: ['vocab_id']
      },
      {
        name: 'idx_vocab_mapping_book_grade',
        fields: ['book_id', 'grade']
      },
      {
        name: 'idx_vocab_mapping_unit_lesson',
        fields: ['unit', 'lesson']
      }
    ]
  });

module.exports = VocabMapping;