/***********************************************************************************************************************************************************************
 * File Name: tierGrants.service.js
 * Type of Program: Service
 * Description: Snapshots a Tier Plan's current bundle contents (plan_courses/
 *              plan_units/plan_lessons — exactly one of the three per plan,
 *              per the single-type bundle rule) into user_tier_grants for a
 *              given user_tiers row. Shared by the client purchase-capture
 *              flow (controllers/client/tiers.controller.js#captureOrder) and
 *              the admin manual-grant flow (controllers/admin/tiers.controller.js#grantTier)
 *              so both paths produce the same item-specific entitlement.
 * Author: Kenneth Obsequio (@lash0000)
 * Date Created: Aug. 4, 2026
 ***********************************************************************************************************************************************************************/
'use strict';

const {
  mdl_PlanCourses,
  mdl_PlanUnits,
  mdl_PlanLessons,
  mdl_UserTierGrants,
} = require('../models/tiers/tier.associations');

// Replaces every grant row tied to this user_tiers purchase with a fresh
// snapshot of the plan's current bundle — safe to call again on repeat
// purchase/extension of the same plan (refreshes to whatever the plan
// currently contains, in case an admin edited it since the first purchase).
async function snapshotPlanGrants(userTierRow, planId) {
  await mdl_UserTierGrants.destroy({ where: { user_tier_id: userTierRow.tier_id } });
  if (!planId) return;

  const [courseRows, unitRows, lessonRows] = await Promise.all([
    mdl_PlanCourses.findAll({ where: { plan_id: planId }, attributes: ['course_id'] }),
    mdl_PlanUnits.findAll({ where: { plan_id: planId }, attributes: ['unit_id'] }),
    mdl_PlanLessons.findAll({ where: { plan_id: planId }, attributes: ['lesson_id'] }),
  ]);

  const grants = [
    ...courseRows.map((r) => ({ item_type: 'course', item_id: r.course_id })),
    ...unitRows.map((r) => ({ item_type: 'unit', item_id: r.unit_id })),
    ...lessonRows.map((r) => ({ item_type: 'lesson', item_id: r.lesson_id })),
  ];
  if (!grants.length) return;

  await mdl_UserTierGrants.bulkCreate(
    grants.map((g) => ({
      user_tier_id: userTierRow.tier_id,
      user_id:      userTierRow.user_id,
      plan_id:      planId,
      item_type:    g.item_type,
      item_id:      g.item_id,
      granted_at:   new Date(),
    })),
  );
}

module.exports = { snapshotPlanGrants };