<?php

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

class RSVL_Widget_Renderer
{
    public function __construct()
    {
        add_action('wp_footer', [$this, 'render_widget']);
        add_action('wp_enqueue_scripts', [$this, 'enqueue_assets']);
    }

    /**
     * Enqueue frontend CSS and JS.
     */
    public function enqueue_assets()
    {
        if (! $this->should_display()) {
            return;
        }

        self::enqueue_scripts(false);
        wp_localize_script('rsvl-chat-widget', 'rsvlChat', self::script_data(false));
    }

    /**
     * Render the chat widget HTML in the footer.
     */
    public function render_widget()
    {
        if (! $this->should_display()) {
            return;
        }
        self::render_html();
    }

    /**
     * Check if the widget should display on the current page.
     */
    private function should_display(): bool
    {
        // Don't show in admin.
        if (is_admin()) {
            return false;
        }

        if (!RSVL_Index::has_sources()) {
            return false;
        }

        if (!self::passes_api_checks()) {
            return false;
        }

        if (RSVL_Token_Budget::is_limit_reached()) {
            return false;
        }

        if (resolver_get_setting('display_mode') !== 'site') {
            return false;
        }

        $current_id   = get_queried_object_id();
        $excluded_ids = (array) resolver_get_setting('display_excluded_ids');

        // Exclusions always win
        if (is_singular() && in_array($current_id, $excluded_ids, true)) {
            return false;
        }

        // Explicit includes always show
        $included_ids = (array) resolver_get_setting('display_included_ids');
        if (in_array($current_id, $included_ids, true)) {
            return true;
        }

        // All page types — show everywhere not explicitly excluded
        if (resolver_get_setting('display_scope') === 'all') {
            return true;
        }

        // Singular post types
        $singular_types = (array) resolver_get_setting('display_singular_types');
        if (! empty($singular_types) && is_singular($singular_types)) {
            return true;
        }

        // Archive types
        $archives = (array) resolver_get_setting('display_archives');
        foreach ($archives as $key) {
            if ($key === 'category' && is_category()) {
                return true;
            }
            if ($key === 'tag' && is_tag()) {
                return true;
            }
            if ($key === 'author' && is_author()) {
                return true;
            }
            if ($key === 'date' && is_date()) {
                return true;
            }
            if (is_tax($key)) {
                return true;
            }
        }

        // Special pages
        $special = (array) resolver_get_setting('display_special');
        if (in_array('home', $special) && is_home()) {
            return true;
        }
        if (in_array('search', $special) && is_search()) {
            return true;
        }
        if (in_array('404', $special) && is_404()) {
            return true;
        }

        return false;
    }

    /**
     * Enqueue the widget's stylesheet and script: deferred on the site, and
     * loaded normally for the admin preview, whose admin.js depends on it.
     */
    public static function enqueue_scripts(bool $is_preview): void
    {
        wp_enqueue_style(
            'rsvl-chat-widget',
            RSVL_PLUGIN_URL . 'public/css/chat-widget.css',
            [],
            RSVL_VERSION
        );

        $load = $is_preview ? true : ['strategy' => 'defer', 'in_footer' => true];

        // The Markdown renderer, which the Chats screen shares.
        wp_register_script('rsvl-markdown', RSVL_PLUGIN_URL . 'public/js/markdown.js', [], RSVL_VERSION, $load);

        wp_enqueue_script(
            'rsvl-chat-widget',
            RSVL_PLUGIN_URL . 'public/js/chat-widget.js',
            ['rsvl-markdown'],
            RSVL_VERSION,
            $load
        );
        RSVL_Script_Strings::attach('rsvl-chat-widget', 'widget');
    }

    /**
     * The widget script's settings (rsvlChat). The admin preview is rendered
     * without a shadow root.
     */
    public static function script_data(bool $is_preview): array
    {
        $options   = self::get_options();
        $hp_fields = resolver_get_honeypot_fields();

        return [
            'ajaxUrl'      => admin_url('admin-ajax.php'),
            'nonce'        => wp_create_nonce('resolver_chat_nonce'),
            'botName'      => resolver_get_setting('bot_name'),
            'greeting'     => resolver_get_setting('greeting_message'),
            'position'     => resolver_get_setting('position'),
            'avatarUrl'    => $options['avatar_url'],
            'avatarRadius' => $options['avatar_radius'],
            'iconUrl'      => $options['icon_url'],
            'rateSvgUp'    => resolver_get_svg('like'),
            'rateSvgDown'  => resolver_get_svg('dislike'),
            'jsField'      => $hp_fields['js'],
            'cssUrl'       => RSVL_PLUGIN_URL . 'public/css/chat-widget.css?ver=' . RSVL_VERSION,
            'useShadow'    => ! $is_preview,
            // For numbers formatted in the browser, e.g. "de-DE".
            'locale' => str_replace('_', '-', determine_locale()),
        ];
    }

    /**
     * Readiness of the admin preview, independent of public-site visibility.
     */
    public static function is_preview_ready(): bool
    {
        return RSVL_Index::has_trained_content() && self::passes_api_checks();
    }

    /**
     * Output the chat widget HTML. Called both from the frontend hook and the admin preview.
     */
    public static function render_html(bool $is_preview = false): void
    {
        // Keep the preview mounted so it can become usable without a reload.
        $hidden        = $is_preview && ! self::is_preview_ready();
        $options       = self::get_options();
        $hp_fields     = resolver_get_honeypot_fields();
        $hp_field      = $hp_fields['hp'];
        $accent        = resolver_get_setting('accent_color');
        $position      = resolver_get_setting('position');
        $bot_name      = resolver_get_setting('bot_name');
        $greeting      = resolver_get_setting('greeting_message');
        $avatar_url    = $options['avatar_url'];
        $avatar_radius = $options['avatar_radius'];
        $icon_url      = $options['icon_url'];
        $extra_class   = $is_preview ? ' rsvl-chat--preview' : '';
        if ($avatar_url) {
            $extra_class .= ' rsvl-chat--has-avatar';
        }
        ?>
        <div id="rsvl-chat" class="rsvl-chat rsvl-position-<?php echo esc_attr($position . $extra_class); ?>"<?php echo $hidden ? ' hidden' : ''; ?> style="--rsvl-accent: <?php echo esc_attr($accent); ?>; --rsvl-avatar-radius: <?php echo esc_attr($avatar_radius); ?>px;">
            <?php if ($is_preview) : ?>
                <div class="rsvl-preview-label">✨ <?php esc_html_e('Try your chatbot', 'resolver-ai-chatbot'); ?></div>
            <?php endif; ?>
            <button class="rsvl-toggle" aria-label="<?php esc_attr_e('Open chat', 'resolver-ai-chatbot'); ?>">
                <?php if ($icon_url) : ?>
                    <img class="rsvl-icon-chat" src="<?php echo esc_url($icon_url); ?>" alt="" width="28" height="28">
                <?php else : ?>
                    <svg class="rsvl-icon-chat" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
                        <path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z"/>
                    </svg>
                <?php endif; ?>
                <svg class="rsvl-icon-close" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" style="display:none;">
                    <line x1="18" y1="6" x2="6" y2="18"/>
                    <line x1="6" y1="6" x2="18" y2="18"/>
                </svg>
            </button>
            <div class="rsvl-panel<?php echo $is_preview ? ' is-admin' : ''; ?>" hidden>
                <div class="rsvl-header">
                    <span class="rsvl-bot-name"><?php echo esc_html($bot_name); ?></span>
                    <button class="rsvl-new-chat" aria-label="<?php esc_attr_e('Start a new chat', 'resolver-ai-chatbot'); ?>" title="<?php esc_attr_e('Start a new chat', 'resolver-ai-chatbot'); ?>"><?php resolver_svg('new-chat'); ?></button>
                    <button class="rsvl-close" aria-label="<?php esc_attr_e('Close chat', 'resolver-ai-chatbot'); ?>" title="<?php esc_attr_e('Close chat', 'resolver-ai-chatbot'); ?>">
                        <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
                            <line x1="18" y1="6" x2="6" y2="18"/>
                            <line x1="6" y1="6" x2="18" y2="18"/>
                        </svg>
                    </button>
                </div>
                <div class="rsvl-messages" role="log" aria-live="polite">
                    <div class="rsvl-message rsvl-message-bot">
                        <div class="rsvl-message-content"><?php echo esc_html($greeting); ?></div>
                    </div>
                </div>
                <div class="rsvl-input-area">
                    <input type="text" name="<?php echo esc_attr($hp_field); ?>" tabindex="-1" autocomplete="off" aria-hidden="true" style="position:absolute;opacity:0;pointer-events:none;height:0;width:0;overflow:hidden;" value="">
                    <textarea id="rsvl-input" type="text" class="rsvl-input" placeholder="<?php esc_attr_e('Type a message...', 'resolver-ai-chatbot'); ?>" aria-label="<?php esc_attr_e('Chat message', 'resolver-ai-chatbot'); ?>" rows="2"></textarea>
                    <button class="rsvl-send" aria-label="<?php esc_attr_e('Send message', 'resolver-ai-chatbot'); ?>" title="<?php esc_attr_e('Send message', 'resolver-ai-chatbot'); ?>" disabled>
                        <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round">
                            <line x1="12" y1="19" x2="12" y2="5"/>
                            <polyline points="5 12 12 5 19 12"/>
                        </svg>
                    </button>
                </div>
                <?php
                // Off unless the site owner turns it on (the show_attribution
                // setting), since WordPress.org requires a credit link to be
                // opt-in. The preview always has it, hidden when off, so ticking
                // the box shows it straight away.
                $show_attribution = (bool) resolver_get_setting('show_attribution');
        if ($show_attribution || $is_preview) : ?>
                <div class="rsvl-panel-footer"<?php echo $show_attribution ? '' : ' style="display:none;"'; ?>>
                    <span><?php
                    /* translators: %s: "Resolver", linked to the Resolver website. */
                    printf(esc_html__('Powered by %s', 'resolver-ai-chatbot'), '<a href="https://resolverchatbot.com" target="_blank" rel="noopener">Resolver</a>');
            ?></span>
                </div>
                <?php endif; ?>
            </div>
        </div>
        <?php
    }

    /**
     * The widget's image options, all off by default.
     *
     * @return array {
     *     @type string $avatar_url    Image shown beside the chatbot's replies.
     *     @type int    $avatar_radius Its corner radius in px.
     *     @type string $icon_url      Image on the chat button instead of the bubble icon.
     * }
     */
    public static function get_options(): array
    {
        $defaults = [
            'avatar_url'    => '',
            'avatar_radius' => 0,
            'icon_url'      => '',
        ];

        /**
         * Filter the widget's image options. Pro sets them from
         * its Appearance settings.
         *
         * @param array $options See RSVL_Widget_Renderer::get_options().
         */
        $options = wp_parse_args((array) apply_filters('resolver_widget_options', $defaults), $defaults);

        return [
            'avatar_url'    => (string) $options['avatar_url'],
            'avatar_radius' => (int) $options['avatar_radius'],
            'icon_url'      => (string) $options['icon_url'],
        ];
    }

    private static function passes_api_checks(): bool
    {
        // Require a chat provider to be selected, and its API key saved.
        $provider = RSVL_Provider::get_provider((string) resolver_get_setting('chat_provider'));
        if (! $provider || ! $provider->is_connected()) {
            return false;
        }

        // Require a chat model to be selected
        if (resolver_get_setting('chat_model') === '') {
            return false;
        }

        // Require an embedding provider to be selected and have active API key
        $embedder = new RSVL_Embedder();
        if (!$embedder->is_available()) {
            return false;
        }

        // Don't show if the configured embedding model's deprecation date has passed.
        $dep_date = $embedder->get_deprecation_date();
        if ($dep_date && strtotime($dep_date) <= time()) {
            return false;
        }

        return true;
    }
}