/***********************************************************************************************************************************************************************
 * File Name: plan_units.mdl.js
 * Type of Program: Model
 * Description: Junction table — links standalone Units to a specific tier plan.
 *              Composite UNIQUE on (plan_id, unit_id) only prevents adding the
 *              same unit twice to the same plan — a unit may belong to many
 *              plans simultaneously (Tier Plans v2, silent duplication across
 *              bundles is intentional; see admin/tiers.controller.js).
 *              Mirrors plan_courses.mdl.js — bundling/display only, not an
 *              access-control mechanism (see canAccessUnit / user_tier_grants).
 * Author: Kenneth Obsequio (@lash0000)
 * Date Created: Aug. 1, 2026
 ***********************************************************************************************************************************************************************/
const { DataTypes } = require('sequelize');
const sequelize = require('../../config/db.config');

const mdl_PlanUnits = sequelize.define('PlanUnit', {
  id:      { type: DataTypes.BIGINT, primaryKey: true, autoIncrement: true },
  plan_id: { type: DataTypes.BIGINT, allowNull: false },
  unit_id: { type: DataTypes.BIGINT, allowNull: false },
}, {
  tableName:  'plan_units',
  timestamps: true,
  paranoid:   false,
});

module.exports = mdl_PlanUnits;