<?php

declare(strict_types=1);

namespace Abovault\Retention;

defined('ABSPATH') || exit;

/**
 * The concrete retention/dunning SEQUENCES — the "sharp" part of the crown jewel.
 * Each sequence is an ordered list of steps: { offset_hours, action, template }.
 *
 *   offset_hours  when the step runs, relative to enrollment start.
 *   action        'email' | 'coupon_email' | 'pause_offer' | 'retry_charge'
 *   template      key resolved by LifecycleMailer to a localized subject + body.
 *
 * Filterable via `abovault_sequence_steps` so merchants/pro can customise without code.
 */
final class SequenceLibrary
{
    /**
     * @return array<int, array{offset_hours:int, action:string, template:string, meta?:array<string,mixed>}>
     */
    public static function steps(string $sequence): array
    {
        $lib = [
            // Dunning — comms alongside the RetryPolicy backoff charges.
            'dunning' => [
                ['offset_hours' => 0,   'action' => 'email', 'template' => 'dunning_1'],
                ['offset_hours' => 48,  'action' => 'email', 'template' => 'dunning_2'],
                ['offset_hours' => 120, 'action' => 'email', 'template' => 'dunning_final'],
            ],
            // Renewal reminder — a few days before the period ends.
            'renewal_reminder' => [
                ['offset_hours' => 0, 'action' => 'email', 'template' => 'renewal_reminder'],
            ],
            // Pre-cancel retention — pause / discount offer before a hard cancel.
            'win_back_offer' => [
                ['offset_hours' => 0, 'action' => 'pause_offer', 'template' => 'win_back_offer'],
            ],
            // Post-cancel win-back — reactivate, then a discount.
            'win_back' => [
                ['offset_hours' => 0,   'action' => 'email',        'template' => 'win_back_1'],
                ['offset_hours' => 168, 'action' => 'coupon_email', 'template' => 'win_back_coupon',
                 'meta' => ['percent' => 30, 'days_valid' => 14]],
            ],
            // Loyalty — subscription anniversary.
            'loyalty' => [
                ['offset_hours' => 0, 'action' => 'coupon_email', 'template' => 'loyalty',
                 'meta' => ['percent' => 15, 'days_valid' => 30]],
            ],
        ];

        $steps = $lib[$sequence] ?? [];

        /**
         * @param array $steps
         * @param string $sequence
         */
        return (array) apply_filters('abovault_sequence_steps', $steps, $sequence);
    }

    public static function count(string $sequence): int
    {
        return count(self::steps($sequence));
    }
}