<?php

namespace FluentCartBreakdance\Admin;

use FluentCartBreakdance\Compatibility\Contracts;
use FluentCartBreakdance\Compatibility\VersionProfiles;

defined('ABSPATH') || exit;

/**
 * WP12A (Golf 4, ELITE-PLAN.md par. 309): "waarschuwt na een FluentCart/
 * Breakdance-update en toont wat er kapot is VOORDAT de site het merkt."
 *
 * Hooks WordPress' own `upgrader_process_complete` (fired once per completed
 * plugin update/install, single or bulk) and, only when the update touched
 * FluentCart, FluentCart Pro, or Breakdance, re-runs Contracts::verify() and
 * VersionProfiles::evaluate() immediately and stores a small summary (never
 * the full per-entry detail, to keep the stored option lean) plus a
 * timestamp in the `fcbd_sentinel_last` option. A dismissible admin_notice
 * (manage_options only) then points administrators at the Health page
 * whenever that summary shows a missing or warn entry.
 *
 * No email is sent, no external request is ever made: this is a same-request,
 * same-site, read-only capability check, exactly like Contracts::verify()
 * itself.
 */
final class Sentinel
{
    public const LAST_RUN_OPTION = 'fcbd_sentinel_last';
    public const NOTICE_DISMISSED_OPTION = 'fcbd_sentinel_notice_dismissed_at';
    public const DISMISS_QUERY_VAR = 'fcbd_dismiss_sentinel';
    public const DISMISS_NONCE_ACTION = 'fcbd_dismiss_sentinel_notice';

    /** Admin screens on which the sentinel notice may appear (plus the Health page). */
    private const NOTICE_SCREENS = ['dashboard', 'plugins', 'update-core'];

    /**
     * Plugin basenames (relative to wp-content/plugins/) this sentinel watches
     * for. Verified against the live install: fluent-cart/fluent-cart.php,
     * fluent-cart-pro/fluent-cart-pro.php, breakdance/plugin.php (sparkcore-shop.local).
     */
    private const WATCHED_PLUGIN_BASENAMES = [
        'fluent-cart/fluent-cart.php',
        'fluent-cart-pro/fluent-cart-pro.php',
        'breakdance/plugin.php',
    ];

    public static function hook(): void
    {
        add_action('upgrader_process_complete', [self::class, 'onUpgradeComplete'], 10, 2);
        add_action('admin_notices', [self::class, 'maybeRenderNotice']);
        add_action('admin_init', [self::class, 'maybeHandleDismiss']);
    }

    /**
     * @param mixed $upgrader Unused: only $hookExtra carries the information
     *                         needed to decide relevance; kept as a parameter
     *                         to match WordPress' own upgrader_process_complete
     *                         signature exactly.
     * @param array<string, mixed> $hookExtra
     */
    public static function onUpgradeComplete($upgrader, array $hookExtra): void
    {
        if (!self::isRelevantUpdate($hookExtra)) {
            return;
        }

        // Defensive: Contracts/VersionProfiles are standalone-loadable files that
        // the bootstrap requires, but this hook fires deep inside wp-admin's
        // upgrader flow. If a future bootstrap change ever drops them again, a
        // missing class here would fatal the UPGRADE SCREEN (seen live on
        // 2026-07-15), which is the worst possible place to fail. Require them
        // explicitly before use; require_once is a no-op when already loaded.
        require_once dirname(__DIR__) . '/Compatibility/Contracts.php';
        require_once dirname(__DIR__) . '/Compatibility/VersionProfiles.php';

        $results = Contracts::verify();
        $profile = VersionProfiles::evaluate();
        $summary = HealthPage::summarizeContracts($results);

        if (function_exists('update_option')) {
            update_option(self::LAST_RUN_OPTION, [
                'checked_at' => function_exists('time') ? time() : 0,
                'trigger' => self::triggerLabel($hookExtra),
                'fluentcart_version' => $profile['version'],
                'profile_status' => $profile['status'],
                'summary' => $summary,
                'has_issue' => self::hasIssue($summary),
            ], false);
        }
    }

    /**
     * Whether an upgrader_process_complete `$hookExtra` payload represents a
     * plugin update (single or bulk) touching one of the watched plugins.
     * Pure/testable: no WordPress call, only array inspection.
     *
     * @param array<string, mixed> $hookExtra
     */
    public static function isRelevantUpdate(array $hookExtra): bool
    {
        if (($hookExtra['action'] ?? '') !== 'update' || ($hookExtra['type'] ?? '') !== 'plugin') {
            return false;
        }

        $plugins = [];

        if (!empty($hookExtra['plugins']) && is_array($hookExtra['plugins'])) {
            $plugins = $hookExtra['plugins'];
        } elseif (!empty($hookExtra['plugin']) && is_string($hookExtra['plugin'])) {
            $plugins = [$hookExtra['plugin']];
        }

        foreach ($plugins as $plugin) {
            if (is_string($plugin) && in_array($plugin, self::WATCHED_PLUGIN_BASENAMES, true)) {
                return true;
            }
        }

        return false;
    }

    /**
     * @param array<string, mixed> $hookExtra
     */
    public static function triggerLabel(array $hookExtra): string
    {
        $plugins = [];

        if (!empty($hookExtra['plugins']) && is_array($hookExtra['plugins'])) {
            $plugins = $hookExtra['plugins'];
        } elseif (!empty($hookExtra['plugin']) && is_string($hookExtra['plugin'])) {
            $plugins = [$hookExtra['plugin']];
        }

        $watched = array_values(array_filter($plugins, static function ($plugin): bool {
            return is_string($plugin) && in_array($plugin, self::WATCHED_PLUGIN_BASENAMES, true);
        }));

        return implode(', ', $watched);
    }

    /**
     * @param array{ok: int, warn: int, missing: int, uncheckable: int} $summary
     */
    public static function hasIssue(array $summary): bool
    {
        return ($summary['missing'] ?? 0) > 0 || ($summary['warn'] ?? 0) > 0;
    }

    public static function maybeRenderNotice(): void
    {
        if (!function_exists('current_user_can') || !current_user_can('manage_options')) {
            return;
        }

        // Limited in scope: only where an administrator manages updates (the
        // Dashboard, Plugins and Updates screens) and on the Health page.
        if (!HealthPage::isNoticeScreen(self::NOTICE_SCREENS)) {
            return;
        }

        $last = function_exists('get_option') ? get_option(self::LAST_RUN_OPTION, null) : null;

        if (!is_array($last) || empty($last['has_issue'])) {
            return;
        }

        $checkedAt = (int) ($last['checked_at'] ?? 0);
        $dismissedAt = function_exists('get_option') ? (int) get_option(self::NOTICE_DISMISSED_OPTION, 0) : 0;

        if ($dismissedAt === $checkedAt) {
            return;
        }

        $summary = is_array($last['summary'] ?? null) ? $last['summary'] : ['ok' => 0, 'warn' => 0, 'missing' => 0, 'uncheckable' => 0];

        $healthUrl = function_exists('admin_url') ? admin_url('options-general.php?page=' . HealthPage::PAGE_SLUG) : '';
        $dismissUrl = self::dismissUrl();

        echo '<div class="notice notice-warning is-dismissible fcbd-sentinel-notice">';
        echo '<p>' . esc_html(sprintf(
            /* translators: 1: trigger plugin label, 2: warn count, 3: missing count. */
            __('SparkCore Commerce sentinel: after the update of %1$s, %2$d warning(s) and %3$d missing interface(s) were found.', 'sparkcore-commerce'),
            (string) ($last['trigger'] ?? ''),
            (int) $summary['warn'],
            (int) $summary['missing']
        )) . ' ';

        if ($healthUrl !== '') {
            echo '<a href="' . esc_url($healthUrl) . '">' . esc_html__('View the health report', 'sparkcore-commerce') . '</a>';
        }

        echo '</p>';

        if ($dismissUrl !== '') {
            echo '<p><a href="' . esc_url($dismissUrl) . '">' . esc_html__('Dismiss this notice', 'sparkcore-commerce') . '</a></p>';
        }

        echo '</div>';
    }

    private static function dismissUrl(): string
    {
        if (!function_exists('admin_url') || !function_exists('wp_nonce_url') || !function_exists('add_query_arg')) {
            return '';
        }

        $base = admin_url('admin.php');
        $url = add_query_arg(self::DISMISS_QUERY_VAR, '1', $base);

        return wp_nonce_url($url, self::DISMISS_NONCE_ACTION);
    }

    public static function maybeHandleDismiss(): void
    {
        if (!function_exists('current_user_can') || !current_user_can('manage_options')) {
            return;
        }

        if (empty($_GET[self::DISMISS_QUERY_VAR])) {
            return;
        }

        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- This IS the nonce value; it is verified with wp_verify_nonce() on the next lines.
        $nonce = isset($_GET['_wpnonce']) ? sanitize_text_field(wp_unslash((string) $_GET['_wpnonce'])) : '';

        if (!function_exists('wp_verify_nonce') || !wp_verify_nonce($nonce, self::DISMISS_NONCE_ACTION)) {
            return;
        }

        $last = function_exists('get_option') ? get_option(self::LAST_RUN_OPTION, null) : null;
        $checkedAt = is_array($last) ? (int) ($last['checked_at'] ?? 0) : 0;

        if (function_exists('update_option')) {
            update_option(self::NOTICE_DISMISSED_OPTION, $checkedAt, false);
        }

        if (function_exists('wp_safe_redirect') && function_exists('remove_query_arg')) {
            wp_safe_redirect(remove_query_arg([self::DISMISS_QUERY_VAR, '_wpnonce']));
            exit;
        }
    }
}