<?php

namespace AOP\App\Frontend;

use AOP\App\Plugin;

/**
 * `[aop_option name="phone"]`: the value of a field on the website, as Output shows it. The name of the shortcode is
 * part of the data contract with Pro (it is in the content of posts): Pro registers the same one.
 *
 * Attributes: `name` (the option name of the field), `default` (shown when the value is empty), and for some types
 * `format` (date, time), `size` (image), `text` and `link` (email, link, file).
 *
 * @since 1.0.0
 */
final class Shortcode
{
    public const TAG = 'aop_option';

    /**
     * The attributes the shortcode knows; others are ignored.
     */
    private const ATTRIBUTES = ['name' => '', 'default' => '', 'format' => '', 'size' => '', 'text' => '', 'link' => ''];

    /**
     * Register on init. Not when Pro has taken over: it registers the shortcode itself.
     */
    public static function register(): void
    {
        if (Plugin::isDisabled()) {
            return;
        }

        add_shortcode(self::TAG, [self::class, 'render']);
    }

    /**
     * @param array|string $atts As WordPress passes them (a string when there are none).
     */
    public static function render($atts): string
    {
        $atts = shortcode_atts(self::ATTRIBUTES, is_array($atts) ? $atts : [], self::TAG);
        $atts = array_map(function ($value) {
            return is_scalar($value) ? (string) $value : '';
        }, $atts);

        $name = $atts['name'];

        if ($name === '' || PublicFields::get($name) === null) {
            // Never the default here: the output must not tell whether an option exists.
            return self::explain($name);
        }

        $args = array_filter(array_diff_key($atts, ['name' => true, 'default' => true]), 'strlen');
        $html = Output::html($name, $args);

        return $html !== '' ? $html : esc_html($atts['default']);
    }

    /**
     * Why nothing is shown, as an HTML comment for someone who may see the options (manage_options); nothing for
     * everyone else.
     */
    private static function explain(string $name): string
    {
        if (!current_user_can('manage_options')) {
            return '';
        }

        if ($name === '') {
            $reason = __('the shortcode has no name="..."', 'admin-options-pages');
        } elseif (in_array($name, (array) get_option(Plugin::PREFIX_ . 'option_names', []), true)) {
            $reason = __('"Use in shortcode and blocks" is off for this field, or its type cannot be shown', 'admin-options-pages');
        } else {
            $reason = __('this is not an option of Admin Options Pages', 'admin-options-pages');
        }

        // "--" would end the comment early.
        return sprintf('<!-- aop_option %s: %s -->', str_replace('--', '- -', esc_html($name)), str_replace('--', '- -', esc_html($reason)));
    }
}