<?php

namespace AOP\App\Admin\AdminPages;

use AOP\App\Enqueue;
use AOP\App\Plugin;

/**
 * "What's new": the page that tells what changed in the latest release with news (VERSION), like the About page of
 * WordPress after an update (it uses the classes of wp-admin/css/about.css, which every admin screen loads). The page
 * of an earlier release stays available as an archive (`&version=1.0`). After an update an administrator sees a
 * notice that links to it, until the page was opened or the notice dismissed.
 */
class SubpageWhatsNew
{
    public const SLUG = Plugin::_NAME . '_whats_new';

    /** The release this page is about. */
    public const VERSION = '1.1.0';

    /** Earlier releases with a page of their own: `&version=` => view. */
    public const ARCHIVE = ['1.0' => 'whats-new-1.0.php'];

    /**
     * The release whose news this site has had (VERSION when it was installed with it). A site where it is older or
     * missing was updated: it gets the notice once.
     */
    public const SEEN_OPTION = Plugin::PREFIX_ . 'whats_new_version';

    /** Set when an update needs the notice (the version it is for); removed when it was seen or dismissed. */
    public const SHOW_OPTION = Plugin::PREFIX_ . 'show_whats_new';

    public const DISMISS_ACTION = Plugin::PREFIX_ . 'dismiss_whats_new';

    public const SCREEN = 'admin_page_' . self::SLUG;

    public static function register(): void
    {
        add_action('admin_init', [self::class, 'checkRelease']);
        add_action('admin_notices', [self::class, 'notice']);
        add_action('wp_ajax_' . self::DISMISS_ACTION, [self::class, 'dismiss']);
        add_action('admin_enqueue_scripts', [self::class, 'enqueue']);
    }

    /**
     * @param string $version Empty for the latest release, or a key of ARCHIVE.
     */
    public static function url(string $version = ''): string
    {
        return admin_url('admin.php?page=' . self::SLUG . ($version !== '' ? '&version=' . rawurlencode($version) : ''));
    }

    /**
     * A site that has not had the news of this release yet (an update from 1.0 or older) gets the notice once. A
     * fresh install has SEEN_OPTION already (Plugin::addOptions()).
     */
    public static function checkRelease(): void
    {
        if (get_option(self::SEEN_OPTION) === self::VERSION) {
            return;
        }

        update_option(self::SEEN_OPTION, self::VERSION, false);
        self::remember();
    }

    /**
     * An update from an older version: show the notice.
     */
    public static function remember(): void
    {
        update_option(self::SHOW_OPTION, self::VERSION, false);
    }

    public static function forget(): void
    {
        delete_option(self::SHOW_OPTION);
    }

    public static function enqueue(): void
    {
        $screen = function_exists('get_current_screen') ? get_current_screen() : null;

        if (!$screen || $screen->id !== self::SCREEN) {
            return;
        }

        wp_enqueue_style(
            Plugin::PREFIX . 'whats-new',
            Plugin::assetsUrl() . 'css/aop-whats-new.css',
            [],
            Enqueue::version('css/aop-whats-new.css')
        );

        // The code example in the colors of the code editor of WordPress (CodeMirror, as in the plugin editor):
        // colored once with its runMode, it stays a plain block of text. False when the user switched syntax
        // highlighting off in the profile; then it stays plain.
        if (wp_enqueue_code_editor(['type' => 'application/x-httpd-php'])) {
            wp_add_inline_script(
                'wp-codemirror',
                'document.addEventListener("DOMContentLoaded",function(){document.querySelectorAll(".aop-whats-new__code code").forEach(function(code){var text=code.textContent;code.textContent="";window.wp.CodeMirror.runMode(text,{name:"php",startOpen:true},code);code.parentNode.classList.add("cm-s-default");});});'
            );
        }
    }

    /**
     * The notice after an update, for administrators, only where it belongs: the dashboard, the list of plugins and
     * the screens of this plugin (not on this page itself). WordPress.org asks plugins not to take over the admin.
     */
    public static function notice(): void
    {
        if (!get_option(self::SHOW_OPTION) || !current_user_can('manage_options') || !self::isNoticeScreen()) {
            return;
        }

        printf(
            '<div class="notice notice-info is-dismissible aop-whats-new-notice" data-nonce="%1$s" data-action="%2$s"><p><strong>%3$s</strong> %4$s</p><p><a class="button button-primary" href="%5$s">%6$s</a></p></div>',
            esc_attr(wp_create_nonce(self::DISMISS_ACTION)),
            esc_attr(self::DISMISS_ACTION),
            esc_html__('Admin Options Pages 1.1 is here.', 'admin-options-pages'),
            esc_html__('You now choose per page which roles can edit it. Have a look at who can edit your pages.', 'admin-options-pages'),
            esc_url(self::url()),
            esc_html__("See what's new", 'admin-options-pages')
        );

        // The close button of WordPress only hides the notice; this remembers it (no jQuery, no extra file).
        wp_print_inline_script_tag(
            'document.addEventListener("click",function(e){var b=e.target.closest(".aop-whats-new-notice .notice-dismiss");if(!b){return;}var n=b.closest(".aop-whats-new-notice"),d=new FormData();d.append("action",n.dataset.action);d.append("_ajax_nonce",n.dataset.nonce);fetch(window.ajaxurl,{method:"POST",body:d,credentials:"same-origin"});});'
        );
    }

    /**
     * The dashboard, the plugins screen or a screen of this plugin. The screens of the plugin are recognized by their
     * page slug: their screen id changes with the translated menu title.
     */
    private static function isNoticeScreen(): bool
    {
        $screen = function_exists('get_current_screen') ? get_current_screen() : null;

        if (!$screen || $screen->id === self::SCREEN) {
            return false;
        }

        if (in_array($screen->id, ['dashboard', 'plugins'], true)) {
            return true;
        }

        $page = isset($_GET['page']) ? sanitize_key(wp_unslash($_GET['page'])) : ''; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- only decides where a notice shows.

        return strpos($page, Plugin::_NAME . '_') === 0;
    }

    /**
     * The notice was closed: do not show it again.
     */
    public static function dismiss(): void
    {
        if (!current_user_can('manage_options') || !check_ajax_referer(self::DISMISS_ACTION, false, false)) {
            wp_send_json_error(null, 403);
        }

        self::forget();

        wp_send_json_success();
    }

    public static function view(): void
    {
        // Seen: the notice has done its work.
        self::forget();

        $image = function (string $file, string $alt, int $width, int $height): string {
            return sprintf(
                '<div class="about__image"><img loading="lazy" src="%s" alt="%s" width="%d" height="%d" /></div>',
                esc_url(Plugin::assetsUrl() . 'images/whats-new/' . $file . '?ver=' . Enqueue::version('images/whats-new/' . $file)),
                esc_attr($alt),
                $width,
                $height
            );
        };

        $version = isset($_GET['version']) ? sanitize_text_field(wp_unslash($_GET['version'])) : ''; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- only chooses which page to show.

        include __DIR__ . '/views/' . (self::ARCHIVE[$version] ?? 'whats-new.php');
    }
}