CluPilotCloud/tests/Feature/Billing/PlanChangeTest.php

<?php

use App\Models\Subscription;
use App\Services\Billing\PlanChange;
use Illuminate\Support\Carbon;

it('freezes what the customer bought against later price rises', function () {
    $subscription = Subscription::factory()->plan('team')->create();
    $bookedPrice = $subscription->price_cents;

    config()->set('provisioning.plans.team.price_cents', $bookedPrice * 2);

    // The existing customer keeps their terms — that is the entire point.
    expect($subscription->fresh()->price_cents)->toBe($bookedPrice)
        ->and(Subscription::snapshotFrom('team')['price_cents'])->toBe($bookedPrice * 2);
});

it('refuses to rewrite a snapshot after the fact', function () {
    $subscription = Subscription::factory()->plan('team')->create();

    expect(fn () => $subscription->update(['price_cents' => 1]))
        ->toThrow(RuntimeException::class, 'immutable');

    expect($subscription->fresh()->price_cents)->toBe(Subscription::snapshotFrom('team')['price_cents']);

    // The rejected value is still on the in-memory model, so it has to be
    // discarded before anything else can be saved — otherwise the next write
    // carries the forbidden change along and is refused too.
    $subscription->refresh();

    // Operational fields still move.
    $subscription->update(['pending_plan' => 'start']);
    expect($subscription->fresh()->pending_plan)->toBe('start');
});

it('charges only the remaining days when upgrading mid-month', function () {
    $start = Carbon::parse('2026-08-01');
    $subscription = Subscription::factory()->plan('start')->create([
        'current_period_start' => $start,
        'current_period_end' => $start->copy()->addMonth(),
    ]);

    $change = PlanChange::evaluate($subscription, 'team', Carbon::parse('2026-08-16'));

    $startPrice = Subscription::snapshotFrom('start')['price_cents'];
    $teamPrice = Subscription::snapshotFrom('team')['price_cents'];
    $expected = (int) round($teamPrice * 16 / 31) - (int) round($startPrice * 16 / 31);

    expect($change->isUpgrade)->toBeTrue()
        ->and($change->allowedNow)->toBeTrue()
        ->and($change->chargeCents)->toBe($expected)
        ->and($change->chargeCents)->toBeLessThan($teamPrice)
        ->and($change->chargeCents)->toBeGreaterThan(0);
});

it('makes an upgrade on the last day cost almost nothing', function () {
    $start = Carbon::parse('2026-08-01');
    $subscription = Subscription::factory()->plan('start')->create([
        'current_period_start' => $start,
        'current_period_end' => $start->copy()->addMonth(),
    ]);

    $change = PlanChange::evaluate($subscription, 'business', Carbon::parse('2026-08-31'));

    // One day of the difference, not a month of it.
    expect($change->remainingDays)->toBe(1)
        ->and($change->chargeCents)->toBeLessThan(2000);
});

it('holds a downgrade until the term the customer paid for is over', function () {
    $start = Carbon::parse('2026-01-01');
    $yearly = Subscription::factory()->plan('business', Subscription::TERM_YEARLY)->create([
        'current_period_start' => $start,
        'current_period_end' => $start->copy()->addYear(),
    ]);

    $change = PlanChange::evaluate($yearly, 'start', Carbon::parse('2026-03-15'));

    // Someone on a yearly contract bought a year, not three months.
    expect($change->isUpgrade)->toBeFalse()
        ->and($change->allowedNow)->toBeFalse()
        ->and($change->chargeCents)->toBe(0)
        ->and($change->effectiveAt->toDateString())->toBe('2027-01-01');
});

it('lets a monthly customer move down at the end of the month', function () {
    $start = Carbon::parse('2026-08-01');
    $monthly = Subscription::factory()->plan('business')->create([
        'current_period_start' => $start,
        'current_period_end' => $start->copy()->addMonth(),
    ]);

    expect(PlanChange::evaluate($monthly, 'team', Carbon::parse('2026-08-10'))->effectiveAt->toDateString())
        ->toBe('2026-09-01');
});

it('credits only the unused part of the difference for a goodwill downgrade', function () {
    $start = Carbon::parse('2026-08-01');
    $subscription = Subscription::factory()->plan('business')->create([
        'current_period_start' => $start,
        'current_period_end' => $start->copy()->addMonth(),
    ]);

    // 11 days left of 31: they used the expensive plan for the other 20.
    $credit = PlanChange::goodwillCredit($subscription, 'team', Carbon::parse('2026-08-21'));

    $difference = Subscription::snapshotFrom('business')['price_cents'] - Subscription::snapshotFrom('team')['price_cents'];
    expect($credit)->toBe((int) round($difference * 11 / 31))
        ->and($credit)->toBeLessThan($difference);
});

it('will not call an upgrade a credit', function () {
    $subscription = Subscription::factory()->plan('start')->create();

    expect(fn () => PlanChange::goodwillCredit($subscription, 'business'))
        ->toThrow(RuntimeException::class);
});

it('prices a yearly term as twelve months of the same plan', function () {
    $monthly = Subscription::snapshotFrom('team');
    $yearly = Subscription::snapshotFrom('team', Subscription::TERM_YEARLY);

    // Any discount belongs in the catalogue, not hidden in the conversion.
    expect($yearly['price_cents'])->toBe($monthly['price_cents'] * 12);
});