<?php
// includes/catalog.php
// Shared Catalog loader + helpers (PHP). Mirrors shared/a11ybridge.catalog.json
// One source of truth for dropdowns + normalization (frontend + admin + proxy).

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

function a11ybridge_load_catalog(): array {
    static $cache = null;
    if (is_array($cache)) return $cache;
    $path = plugin_dir_path(__FILE__) . '../shared/a11ybridge.catalog.json';
    if (!file_exists($path)) { $cache = []; return $cache; }

    $raw = file_get_contents($path);
    $json = json_decode($raw, true);
    $cache = is_array($json) ? $json : [];
    return $cache;
}

function a11ybridge_catalog_get_context(string $contextId): array {
    $cat = a11ybridge_load_catalog();
    $ctx = $cat['contexts'][$contextId] ?? [];
    return is_array($ctx) ? $ctx : [];
}

// PHP 7.4 compatibility: list check
function a11ybridge_is_list_array($arr): bool {
    if (!is_array($arr)) return false;
    $i = 0;
    foreach ($arr as $k => $_) {
        if ($k !== $i) return false;
        $i++;
    }
    return true;
}

function a11ybridge_catalog_context(string $contextId): array {
    $ctx = a11ybridge_catalog_get_context($contextId);
    if (!$ctx) return [];

    // New format: ctx.options = [{value,label},...]
    if (isset($ctx['options']) && is_array($ctx['options'])) {
        $out = [];
        foreach ($ctx['options'] as $opt) {
            if (!is_array($opt)) continue;
            $v = (string)($opt['value'] ?? $opt['id'] ?? '');
            $l = (string)($opt['label'] ?? $v);
            if ($v === '') continue;
            $out[] = ['value'=>$v, 'id'=>$v, 'label'=>$l];
        }
        return $out;
    }

    // Legacy format: [[id,label],...]
    if (a11ybridge_is_list_array($ctx)) {
        $out = [];
        foreach ($ctx as $row) {
            if (!is_array($row)) continue;
            $v = (string)($row['value'] ?? $row['id'] ?? '');
            $l = (string)($row['label'] ?? $v);
            if ($v === '') continue;
            $out[] = ['value'=>$v, 'id'=>$v, 'label'=>$l];
        }
        return $out;
    }

    return [];
}

function a11ybridge_catalog_alias_group(string $group, string $value): string {
    $cat = a11ybridge_load_catalog();
    $aliases = $cat['aliases'][$group] ?? null;
    if (!is_array($aliases)) return $value;

    $k = strtolower(trim((string)$value));
    return isset($aliases[$k]) ? (string)$aliases[$k] : $value;
}

// Backward compat:
// - if $key is alias-group, use it
// - else infer group from context id
function a11ybridge_catalog_alias(string $key, string $value): string {
    $cat = a11ybridge_load_catalog();
    if (isset($cat['aliases'][$key]) && is_array($cat['aliases'][$key])) {
        return a11ybridge_catalog_alias_group($key, $value);
    }

    $lc = strtolower($key);
    if (strpos($lc, 'language') !== false) return a11ybridge_catalog_alias_group('languages', $value);
    if (strpos($lc, 'level') !== false) return a11ybridge_catalog_alias_group('levels', $value);
    return $value;
}

function a11ybridge_catalog_default(string $contextId, string $fallback = ''): string {
    $ctx = a11ybridge_catalog_get_context($contextId);
    $def = $ctx['default'] ?? $fallback;
    return is_string($def) ? $def : $fallback;
}

function a11ybridge_catalog_canonical(string $contextId, $value, string $fallbackDefault = ''): string {
    $value = is_string($value) ? $value : (string)$value;

    $lc = strtolower($contextId);
    if (strpos($lc, 'language') !== false) $value = a11ybridge_catalog_alias_group('languages', $value);
    if (strpos($lc, 'level') !== false) $value = a11ybridge_catalog_alias_group('levels', $value);
    $opts = a11ybridge_catalog_context($contextId);
    if ($opts) {
        $needle = strtolower(trim($value));
        foreach ($opts as $opt) {
            $ov = (string)($opt['value'] ?? $opt['id'] ?? '');
            if ($ov !== '' && strtolower($ov) === $needle) {
                return $ov;
            }
        }
    }

    $def = a11ybridge_catalog_default($contextId, $fallbackDefault);
    return $def !== '' ? $def : $fallbackDefault;
}

function a11ybridge_catalog_label(string $contextId, $value, string $fallback = ''): string {
    $canon = a11ybridge_catalog_canonical($contextId, (string)$value, $fallback);
    foreach (a11ybridge_catalog_context($contextId) as $opt) {
        $ov = (string)($opt['value'] ?? $opt['id'] ?? '');
        if ($ov === $canon) return (string)($opt['label'] ?? $canon);
    }
    return $fallback !== '' ? $fallback : $canon;
}
function a11ybridge_catalog_options_html(string $contextId, $selected = null, string $fallbackDefault = ''): string {
    $sel = a11ybridge_catalog_canonical($contextId, (string)($selected ?? ''), $fallbackDefault);
    $html = '';
    foreach (a11ybridge_catalog_context($contextId) as $opt) {
        $v = (string)($opt['value'] ?? $opt['id'] ?? '');
        $l = (string)($opt['label'] ?? $v);
        if ($v === '') continue;
        $html .= sprintf(
            '<option value="%s"%s>%s</option>',
            esc_attr($v),
            selected($v, $sel, false),
            esc_html($l)
        );
    }
    return $html;
}