<?php
/**
 * Helper functions for the plugin
 *
 * @package WP_Graphql_YOAST_SEO
 */

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

use WPGraphQL\AppContext;

/**
 * Format string for GraphQL.
 *
 * @param string $string String to format.
 * @return string|null
 */
function wp_gql_seo_format_string($string)
{
    return isset($string) ? html_entity_decode(trim($string)) : null;
}

/**
 * Replace variables in string.
 *
 * @param string $string String with variables.
 * @return string|null
 */
function wp_gql_seo_replace_vars($string)
{
    static $objects = null;
    if (null === $objects) {
        // Merge registered post types and taxonomies together and pass them through.
        $objects = array_merge(get_post_types(), get_taxonomies());
    }
    return isset($string) ? wpseo_replace_vars($string, $objects) : null;
}

/**
 * Get OG image ID from Yoast SEO.
 *
 * @param array $images Array of images from Yoast SEO.
 * @return string|null
 */
function wp_gql_seo_get_og_image($images)
{
    if (empty($images)) {
        return __return_empty_string();
    }

    $image = reset($images);

    if (empty($image)) {
        return __return_empty_string();
    }

    if (!isset($image['url'])) {
        return __return_empty_string();
    }
    // Remove image sizes from url
    $url = preg_replace('/(.*)-\d+x\d+\.(jpg|png|gif)$/', '$1.$2', $image['url']);
    // If the image is equal as the original and the original has an id, return this ID
    if (isset($image['id']) && $url === $image['url']) {
        return $image['id'];
    }
    return wp_gql_seo_attachment_url_to_postid($url);
}

/**
 * Normalize field key names for GraphQL.
 *
 * @param string $field_key Field key to normalize.
 * @return string
 */
function wp_gql_seo_get_field_key($field_key)
{
    $field_key = lcfirst(preg_replace('/[^a-zA-Z0-9 \-]/', ' ', $field_key));
    $field_key = lcfirst(str_replace('_', ' ', ucwords($field_key, '_')));
    $field_key = lcfirst(str_replace('-', ' ', ucwords($field_key, '_')));
    $field_key = lcfirst(str_replace(' ', '', ucwords($field_key, ' ')));

    return $field_key;
}

/**
 * Generate cache key for attachment URL.
 * Only declare if not already defined (e.g., by VIP platform).
 *
 * @param string $url URL to generate cache key for.
 * @return string
 */
if (!function_exists('wpcom_vip_attachment_cache_key')) {
    function wpcom_vip_attachment_cache_key($url)
    {
        return 'wpcom_vip_attachment_url_post_id_' . md5($url);
    }
}

/**
 * Get post ID from attachment URL with caching.
 * Only declare if not already defined (e.g., by VIP platform).
 *
 * @param string $url URL to get post ID for.
 * @return int|null
 */
if (!function_exists('wpcom_vip_attachment_url_to_postid')) {
    function wpcom_vip_attachment_url_to_postid($url)
    {
        $cache_key = wpcom_vip_attachment_cache_key($url);
        $id = wp_cache_get($cache_key);
        if (false === $id) {
            $id = attachment_url_to_postid($url); // phpcs:ignore
            if (empty($id)) {
                wp_cache_set(
                    $cache_key,
                    'not_found',
                    'default',
                    12 * HOUR_IN_SECONDS + mt_rand(0, 4 * HOUR_IN_SECONDS) // phpcs:ignore
                );
                $id = null; // Set $id to null instead of false
            } else {
                wp_cache_set(
                    $cache_key,
                    $id,
                    'default',
                    24 * HOUR_IN_SECONDS + mt_rand(0, 12 * HOUR_IN_SECONDS) // phpcs:ignore
                );
            }
        } elseif ('not_found' === $id) {
            return false;
        }

        return $id;
    }
}

/**
 * Wrapper for wpcom_vip_attachment_url_to_postid that returns null instead of false.
 * This is needed for GraphQL compatibility - fixes
 * "Cannot return null for non-nullable field 'MediaItem.id'" errors.
 *
 * @see https://github.com/ashhitch/wp-graphql-yoast-seo/issues/132
 * @param string $url URL to get post ID for.
 * @return int|null
 */
function wp_gql_seo_attachment_url_to_postid($url)
{
    static $memo = [];
    if (!array_key_exists($url, $memo)) {
        $id = wpcom_vip_attachment_url_to_postid($url);
        $memo[$url] = false === $id || empty($id) ? null : $id;
    }
    return $memo[$url];
}

/**
 * Build content types data array for GraphQL schema.
 *
 * @param array $types Post types.
 * @return array
 */
function wp_gql_seo_build_content_types($types)
{
    $carry = [];
    foreach ($types as $type) {
        $post_type_object = get_post_type_object($type);
        if ($post_type_object->graphql_single_name) {
            $carry[wp_gql_seo_get_field_key($post_type_object->graphql_single_name)] = ['type' => 'SEOContentType'];
        }
    }
    return $carry;
}

/**
 * Build taxonomy types data array for GraphQL schema.
 *
 * @param array $taxonomies Taxonomies.
 * @return array
 */
function wp_gql_seo_build_taxonomy_types($taxonomies)
{
    $carry = [];
    foreach ($taxonomies as $taxonomy) {
        $taxonomy_object = get_taxonomy($taxonomy);
        if ($taxonomy_object->graphql_single_name) {
            $carry[wp_gql_seo_get_field_key($taxonomy_object->graphql_single_name)] = ['type' => 'SEOTaxonomyType'];
        }
    }
    return $carry;
}

/**
 * Get full head content from Yoast SEO.
 *
 * Delegates to wp_gql_seo_get_head_obj to avoid calling get_head() twice
 * when both fullHead and head are requested for the same meta object.
 *
 * @param \Yoast\WP\SEO\Surfaces\Values\Meta|bool $metaForPost Meta object.
 * @return string
 */
function wp_gql_seo_get_full_head($metaForPost)
{
    return wp_gql_seo_get_head_obj($metaForPost)['html'];
}

/**
 * Get structured head (html + json) from Yoast SEO.
 *
 * @param \Yoast\WP\SEO\Surfaces\Values\Meta|bool $metaForPost Meta object.
 * @return array
 */
function wp_gql_seo_get_head_obj($metaForPost)
{
    static $memo = [];
    if ($metaForPost !== false) {
        $key = spl_object_hash($metaForPost);
        if (!isset($memo[$key])) {
            $head = $metaForPost->get_head();
            $html = is_string($head) ? $head : $head->html;
            $json = is_object($head) && isset($head->json) ? $head->json : [];

            // Keep the meta object referenced so its hash cannot be reused.
            $memo[$key] = [
                'meta' => $metaForPost,
                'data' => [
                    'html' => $html,
                    'json' => wp_json_encode($json, JSON_UNESCAPED_SLASHES),
                ],
            ];
        }
        return $memo[$key]['data'];
    }

    return [
        'html' => '',
        'json' => wp_json_encode([], JSON_UNESCAPED_SLASHES),
    ];
}

/**
 * Safely read a property from a Yoast Indexable (or any object/array).
 *
 * @param mixed  $indexable The indexable object (or null/false).
 * @param string $key       The property key.
 * @return mixed|null
 */
function wp_gql_seo_indexable_prop($indexable, $key)
{
    if (!is_object($indexable) || !isset($indexable->{$key})) {
        return null;
    }

    return $indexable->{$key};
}

/**
 * Build the SEOAnalysis data array from an Indexable.
 *
 * @param mixed $indexable The indexable object (or null/false).
 * @return array
 */
function wp_gql_seo_build_analysis($indexable)
{
    if (!is_object($indexable)) {
        return [
            'keywordScore' => null,
            'readabilityScore' => null,
            'inclusiveLanguageScore' => null,
            'linkCount' => null,
            'incomingLinkCount' => null,
        ];
    }

    return [
        'keywordScore' => isset($indexable->primary_focus_keyword_score)
            ? (int) $indexable->primary_focus_keyword_score
            : null,
        'readabilityScore' => isset($indexable->readability_score) ? (int) $indexable->readability_score : null,
        'inclusiveLanguageScore' => isset($indexable->inclusive_language_score)
            ? (int) $indexable->inclusive_language_score
            : null,
        'linkCount' => isset($indexable->link_count) ? (int) $indexable->link_count : null,
        'incomingLinkCount' => isset($indexable->incoming_link_count) ? (int) $indexable->incoming_link_count : null,
    ];
}

/**
 * Build the SEORobots data array from Yoast robots array and Indexable.
 *
 * @param array $robots   The robots array from Meta (index/follow keys).
 * @param mixed $indexable The indexable object (or null/false).
 * @return array
 */
function wp_gql_seo_build_robots($robots, $indexable)
{
    return [
        'noindex' => isset($robots['index']) ? wp_gql_seo_format_string($robots['index']) : null,
        'nofollow' => isset($robots['follow']) ? wp_gql_seo_format_string($robots['follow']) : null,
        'noarchive' => boolval(wp_gql_seo_indexable_prop($indexable, 'is_robots_noarchive')),
        'noimageindex' => boolval(wp_gql_seo_indexable_prop($indexable, 'is_robots_noimageindex')),
        'nosnippet' => boolval(wp_gql_seo_indexable_prop($indexable, 'is_robots_nosnippet')),
    ];
}

/**
 * Build the Premium social archive data from Yoast SEO Premium options.
 *
 * Returns null for title/description and null for image when the Premium
 * option keys are absent (graceful free-tier fallback).
 *
 * @param string       $option_prefix The option prefix (e.g. 'ptarchive-post', 'tax-category', 'author-wpseo', 'archive-wpseo').
 * @param array        $all           All Yoast SEO options.
 * @param AppContext   $context       The GraphQL AppContext for deferred image loading.
 * @return array
 */
function wp_gql_seo_get_premium_social($option_prefix, $all, $context)
{
    $title_key = 'social-title-' . $option_prefix;
    $desc_key = 'social-description-' . $option_prefix;
    $image_id_key = 'social-image-id-' . $option_prefix;

    $has_premium = isset($all[$title_key]) || isset($all[$desc_key]) || isset($all[$image_id_key]);

    if (!$has_premium) {
        return [
            'title' => null,
            'description' => null,
            'image' => null,
        ];
    }

    return [
        'title' => wp_gql_seo_format_string(wp_gql_seo_replace_vars($all[$title_key] ?? null)),
        'description' => wp_gql_seo_format_string(wp_gql_seo_replace_vars($all[$desc_key] ?? null)),
        'image' => $context->get_loader('post')->load_deferred(absint($all[$image_id_key] ?? 0)),
    ];
}

/**
 * Build content type data for GraphQL schema.
 *
 * @param array      $types   Post types.
 * @param array      $all     All Yoast SEO options.
 * @param AppContext $context The GraphQL AppContext for deferred image loading.
 * @return array
 */
function wp_gql_seo_build_content_type_data($types, $all, $context)
{
    $carry = [];

    // Validate input parameters
    if (!is_array($types) || empty($types) || !is_array($all) || empty($all)) {
        return $carry;
    }

    foreach ($types as $type) {
        $post_type_object = get_post_type_object($type);

        // Validate post type object
        if (!$post_type_object || !$post_type_object->graphql_single_name) {
            continue;
        }

        $tag = wp_gql_seo_get_field_key($post_type_object->graphql_single_name);

        $meta_cache = false;
        $get_meta = function () use ($type, &$meta_cache) {
            if (false === $meta_cache) {
                $meta_cache = ['v' => YoastSEO()->meta->for_post_type_archive($type)];
            }
            return $meta_cache['v'];
        };

        $carry[$tag] = [
            'title' => wp_gql_seo_format_string(wp_gql_seo_replace_vars($all['title-' . $type] ?? null)),
            'metaDesc' => wp_gql_seo_format_string(wp_gql_seo_replace_vars($all['metadesc-' . $type] ?? null)),
            'metaRobotsNoindex' => boolval($all['noindex-' . $type] ?? false),
            'schemaType' => $all['schema-page-type-' . $type] ?? null,
            'articleType' => $all['schema-article-type-' . $type] ?? null,
            'schema' => function () use ($get_meta) {
                return [
                    'raw' => function () use ($get_meta) {
                        $meta = $get_meta();
                        return !empty($meta) && !empty($meta->schema)
                            ? wp_json_encode($meta->schema, JSON_UNESCAPED_SLASHES)
                            : null;
                    },
                ];
            },
            'archive' => function () use ($get_meta, $post_type_object, $type, $all, $context) {
                $meta = $get_meta();
                return [
                    'hasArchive' => boolval($post_type_object->has_archive),
                    'archiveLink' => apply_filters('wp_gql_seo_archive_link', get_post_type_archive_link($type), $type),
                    'title' => wp_gql_seo_format_string($meta !== false ? $meta->title : null),
                    'metaDesc' => wp_gql_seo_format_string($all['metadesc-ptarchive-' . $type] ?? null),
                    'metaRobotsNoindex' =>
                        $meta !== false && !empty($meta->robots['index']) && $meta->robots['index'] === 'index'
                            ? false
                            : true,
                    'metaRobotsNofollow' =>
                        $meta !== false && !empty($meta->robots['follow']) && $meta->robots['follow'] === 'follow'
                            ? false
                            : true,
                    'metaRobotsIndex' => $meta !== false ? ($meta->robots['index'] ?? 'noindex') : 'noindex',
                    'metaRobotsFollow' => $meta !== false ? ($meta->robots['follow'] ?? 'nofollow') : 'nofollow',
                    'breadcrumbTitle' => wp_gql_seo_format_string($all['bctitle-ptarchive-' . $type] ?? null),
                    'fullHead' => function () use ($meta) {
                        return wp_gql_seo_get_full_head($meta);
                    },
                    'head' => function () use ($meta) {
                        return wp_gql_seo_get_head_obj($meta);
                    },
                    'social' => wp_gql_seo_get_premium_social('ptarchive-' . $type, $all, $context),
                ];
            },
        ];
    }

    return $carry;
}

/**
 * Build taxonomy data for GraphQL schema.
 *
 * @param array      $taxonomies Taxonomies.
 * @param array      $all        All Yoast SEO options.
 * @param AppContext $context    The GraphQL AppContext for deferred image loading.
 * @return array
 */
function wp_gql_seo_build_taxonomy_data($taxonomies, $all, $context)
{
    $carry = [];

    // Validate input parameters
    if (!is_array($taxonomies) || empty($taxonomies) || !is_array($all) || empty($all)) {
        return $carry;
    }

    foreach ($taxonomies as $taxonomy) {
        $taxonomy_object = get_taxonomy($taxonomy);

        // Validate taxonomy object
        if (!$taxonomy_object || !$taxonomy_object->graphql_single_name) {
            continue;
        }

        $tag = wp_gql_seo_get_field_key($taxonomy_object->graphql_single_name);
        $carry[$tag] = [
            'archive' => [
                'title' => wp_gql_seo_format_string(wp_gql_seo_replace_vars($all['title-tax-' . $taxonomy] ?? null)),
                'metaDesc' => wp_gql_seo_format_string(
                    wp_gql_seo_replace_vars($all['metadesc-tax-' . $taxonomy] ?? null)
                ),
                'metaRobotsNoindex' => boolval($all['noindex-tax-' . $taxonomy] ?? false),
                'social' => wp_gql_seo_get_premium_social('tax-' . $taxonomy, $all, $context),
            ],
        ];
    }

    return $carry;
}