<?php

if (!defined('ABSPATH')) {
    exit;
}

/**
 * AJAX handler for Engine Profile CRUD operations.
 *
 * Actions:
 *   abj404_engine_profiles_list   – Return all profiles as JSON.
 *   abj404_engine_profiles_save   – Insert or update a profile.
 *   abj404_engine_profiles_delete – Delete a profile by ID.
 */
class ABJ_404_Solution_Ajax_EngineProfiles {

    /** @return void */
    public static function registerActions(): void {
        ABJ_404_Solution_WPUtils::safeAddAction(
            ABJ_404_Solution_PluginAjaxActions::hook('abj404_engine_profiles_list'),
            'ABJ_404_Solution_Ajax_EngineProfiles::handleList'
        );
        ABJ_404_Solution_WPUtils::safeAddAction(
            ABJ_404_Solution_PluginAjaxActions::hook('abj404_engine_profiles_save'),
            'ABJ_404_Solution_Ajax_EngineProfiles::handleSave'
        );
        ABJ_404_Solution_WPUtils::safeAddAction(
            ABJ_404_Solution_PluginAjaxActions::hook('abj404_engine_profiles_delete'),
            'ABJ_404_Solution_Ajax_EngineProfiles::handleDelete'
        );
    }

    /**
     * Return all profiles as a JSON array.
     *
     * @return void
     */
    public static function handleList(): void {
        if (!ABJ_404_Solution_AjaxRequestContractValidator::requireValidCurrentRequest('ajax-engine-profiles')) {
            return;
        }

        abj_service('ajax_security_gate')->requireAdminWithNonce('abj404_engine_profiles_nonce');

        $resolver = ABJ_404_Solution_EngineProfileResolver::getInstance();
        $profiles = $resolver->getAllProfilesForAdmin();
        // `truncated` travels with the list rather than being inferred from its
        // length: a capped list and a genuinely short one are the same size to
        // a reader, and an admin whose profiles stopped appearing must be able
        // to tell that from having deleted them. Additive, so a client that
        // does not know the field keeps working.
        wp_send_json_success([
            'profiles' => $profiles,
            'truncated' => $resolver->adminProfileListWasTruncated(),
            'limit' => ABJ_404_Solution_EngineProfileRepository::MAX_ADMIN_PROFILES,
        ]);
    }

    /**
     * Insert or update a profile.
     *
     * Expected POST fields: name, url_pattern, is_regex, enabled_engines (JSON),
     * priority, status, and optionally id (for update).
     *
     * @return void
     */
    public static function handleSave(): void {
        if (!ABJ_404_Solution_AjaxRequestContractValidator::requireValidCurrentRequest('ajax-engine-profiles')) {
            return;
        }

        abj_service('ajax_security_gate')->requireAdminWithNonce('abj404_engine_profiles_nonce');

        // Boundary normalizer: $_POST shape probing lives in the VO, not here.
        // See ABJ_404_Solution_EngineProfileSaveRequest.
        $req = ABJ_404_Solution_EngineProfileSaveRequest::fromPost($_POST);

        if (trim($req->getName()) === '') {
            wp_send_json_error(['message' => __('Profile name is required.', '404-solution')]);
            return; // @phpstan-ignore deadCode.unreachable
        }

        if (trim($req->getUrlPattern()) === '') {
            wp_send_json_error(['message' => __('URL pattern is required.', '404-solution')]);
            return; // @phpstan-ignore deadCode.unreachable
        }

        // Validate regex pattern before saving.
        // Patterns are stored WITHOUT PHP delimiters (users write ^/shop/ not #^/shop/#).
        // The resolver wraps with # delimiters at match-time when the first char is not
        // a common delimiter; we mirror that same logic here so validation matches
        // what will actually be executed.
        if ($req->isRegex()) {
            $testPattern      = $req->getUrlPattern();
            $commonDelimiters = ['/', '#', '~', '!', '@', '|', '%'];
            if (!in_array(substr($testPattern, 0, 1), $commonDelimiters, true)) {
                $testPattern = '#' . $testPattern . '#';
            }
            set_error_handler(function (int $errno, string $errstr, string $errfile = '', int $errline = 0): bool { return false; }, E_WARNING);
            $testResult = @preg_match($testPattern, '');
            restore_error_handler();
            if ($testResult === false) {
                wp_send_json_error(['message' => __('Invalid regular expression pattern.', '404-solution')]);
                return; // @phpstan-ignore deadCode.unreachable
            }
        }

        $resolver = ABJ_404_Solution_EngineProfileResolver::getInstance();
        $resultId = $resolver->saveProfile($req->toResolverPayload());

        if ($resultId === false) {
            $dbError = self::readLastWriteError($resolver);
            $logger = abj_service('logging');
            if ($logger !== null) {
                $logger->warn('Ajax_EngineProfiles::handleSave: saveProfile() returned false. id=' . $req->getId() .
                    ', name=' . $req->getName() . ', is_regex=' . $req->getIsRegexInt() .
                    '. Returning HTTP 200 with success=false to AJAX caller.');
            }
            // Surface the wpdb-reported failure so the admin can self-diagnose
            // (table missing, column-count mismatch, deadlock, full disk, etc.)
            // instead of seeing only a canned "Failed to save" message.
            $framing = __('Failed to save engine profile.', '404-solution');
            $message = $dbError !== '' ? $framing . ' (DB error: ' . $dbError . ')' : $framing;
            wp_send_json_error(['message' => $message]);
            return; // @phpstan-ignore deadCode.unreachable
        }

        wp_send_json_success(['id' => $resultId]);
    }

    /**
     * Delete a profile by ID.
     *
     * @return void
     */
    public static function handleDelete(): void {
        if (!ABJ_404_Solution_AjaxRequestContractValidator::requireValidCurrentRequest('ajax-engine-profiles')) {
            return;
        }

        abj_service('ajax_security_gate')->requireAdminWithNonce('abj404_engine_profiles_nonce');

        $id = isset($_POST['id']) ? absint($_POST['id']) : 0;

        if ($id <= 0) {
            wp_send_json_error(['message' => __('Invalid profile ID.', '404-solution')]);
            return; // @phpstan-ignore deadCode.unreachable
        }

        $resolver = ABJ_404_Solution_EngineProfileResolver::getInstance();
        $ok = $resolver->deleteProfile($id);
        if (!$ok) {
            $dbError = self::readLastWriteError($resolver);
            $logger = abj_service('logging');
            if ($logger !== null) {
                $logger->warn('Ajax_EngineProfiles::handleDelete: deleteProfile(' . (int)$id .
                    ') returned false (row missing or DB error). Returning HTTP 200 with success=false to AJAX caller.');
            }
            // Surface the wpdb-reported failure so the admin can self-diagnose
            // instead of seeing only a canned "Failed to delete" message. When
            // the resolver returns false because the row simply wasn't there,
            // last_error is empty and the framing message stands on its own.
            $framing = __('Failed to delete engine profile.', '404-solution');
            $message = $dbError !== '' ? $framing . ' (DB error: ' . $dbError . ')' : $framing;
            wp_send_json_error(['message' => $message]);
            return; // @phpstan-ignore deadCode.unreachable
        }

        wp_send_json_success(['id' => $id]);
    }

    /**
     * Read the write failure without calling an accessor a previous release
     * does not have. A present accessor owns the answer even when it is blank;
     * only the missing-capability branch may use the legacy mutable wpdb value.
     *
     * @param object $resolver
     * @return string
     */
    private static function readLastWriteError($resolver): string {
        if (method_exists($resolver, 'getLastWriteError')) {
            return trim((string)$resolver->getLastWriteError());
        }
        global $wpdb;
        return isset($wpdb->last_error) && is_string($wpdb->last_error)
            ? trim($wpdb->last_error) : '';
    }
}