<?php
/**
 * Instant Indexing - IndexNow integration for AWBSEO.
 *
 * Submits URLs to the IndexNow endpoint (api.indexnow.org, shared with Bing,
 * Yandex, and Cloudflare) automatically on publish/update and on demand.
 *
 * @package AWBSEO
 * @since   1.9.6
 */

defined( 'ABSPATH' ) || exit;

class AWBSEO_Instant_Indexing {

    /* Option keys ---------------------------------------------------------- */
    const OPT_KEY      = 'awbseo_indexnow_key';
    const OPT_LOG      = 'awbseo_indexnow_log';
    const OPT_AUTO     = 'awbseo_indexnow_auto';   // '1' | '0'
    const LOG_LIMIT    = 200;
    const INDEXNOW_URL = 'https://api.indexnow.org/indexnow';

    /* Boot ----------------------------------------------------------------- */

    public static function init() {
        // Serve the key verification file dynamically (no write to disk needed).
        add_action( 'init', [ __CLASS__, 'maybe_serve_key_file' ], 1 );

        // Auto-submit on publish / update.
        add_action( 'transition_post_status', [ __CLASS__, 'on_status_change' ], 10, 3 );
        add_action( 'post_updated',           [ __CLASS__, 'on_post_updated' ],   10, 3 );

        // AJAX handlers (admin-only).
        add_action( 'wp_ajax_awbseo_indexnow_submit',       [ __CLASS__, 'ajax_submit' ] );
        add_action( 'wp_ajax_awbseo_indexnow_submit_all',   [ __CLASS__, 'ajax_submit_all' ] );
        add_action( 'wp_ajax_awbseo_indexnow_generate_key', [ __CLASS__, 'ajax_generate_key' ] );
        add_action( 'wp_ajax_awbseo_indexnow_clear_log',    [ __CLASS__, 'ajax_clear_log' ] );

        // Meta box in the post editor.
        add_action( 'add_meta_boxes', [ __CLASS__, 'register_meta_box' ] );
    }

    /* API key -------------------------------------------------------------- */

    /**
     * Returns the stored key, generating one if none exists yet.
     */
    public static function get_key() {
        $key = get_option( self::OPT_KEY, '' );
        if ( ! $key ) {
            $key = self::make_key();
            update_option( self::OPT_KEY, $key, false );
        }
        return $key;
    }

    private static function make_key() {
        return bin2hex( random_bytes( 16 ) ); // 32 lowercase hex chars.
    }

    /**
     * The URL where IndexNow expects to verify the key.
     */
    public static function key_file_url() {
        return home_url( '/' . self::get_key() . '.txt' );
    }

    /* Key file serving ----------------------------------------------------- */

    /**
     * Intercepts requests for /{key}.txt and outputs the key as plain text.
     * IndexNow crawlers fetch this to verify the key belongs to the site.
     */
    public static function maybe_serve_key_file() {
        $key = get_option( self::OPT_KEY, '' );
        if ( ! $key ) return;

        $path = isset( $_SERVER['REQUEST_URI'] )
            ? parse_url( wp_unslash( $_SERVER['REQUEST_URI'] ), PHP_URL_PATH )
            : '';

        if ( $path === '/' . $key . '.txt' ) {
            // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
            header( 'Content-Type: text/plain; charset=utf-8' );
            header( 'Cache-Control: no-store' );
            echo $key;
            exit;
        }
    }

    /* Auto-submit hooks ---------------------------------------------------- */

    /**
     * Fires when a post transitions to "publish" (new publish).
     */
    public static function on_status_change( $new, $old, $post ) {
        if ( $new !== 'publish' || $old === 'publish' ) return; // Only on first publish.
        if ( ! self::auto_enabled() ) return;
        if ( wp_is_post_revision( $post ) || wp_is_post_autosave( $post ) ) return;
        if ( ! in_array( $post->post_type, self::indexable_types(), true ) ) return;

        $url = get_permalink( $post->ID );
        if ( $url ) self::submit( [ $url ] );
    }

    /**
     * Fires when an already-published post is updated.
     */
    public static function on_post_updated( $post_id, $post_after, $post_before ) {
        if ( $post_after->post_status !== 'publish' ) return;
        if ( ! self::auto_enabled() ) return;
        if ( wp_is_post_revision( $post_after ) ) return;
        if ( ! in_array( $post_after->post_type, self::indexable_types(), true ) ) return;

        $url = get_permalink( $post_id );
        if ( $url ) self::submit( [ $url ] );
    }

    /* Core submit ---------------------------------------------------------- */

    /**
     * Submits one or more URLs to IndexNow.
     *
     * @param  string[] $urls  Absolute URLs.
     * @return true|WP_Error
     */
    public static function submit( array $urls ) {
        $urls = array_values( array_unique( array_filter( $urls ) ) );
        if ( empty( $urls ) ) return new WP_Error( 'no_urls', 'No URLs provided.' );

        $key  = self::get_key();
        $host = parse_url( home_url(), PHP_URL_HOST );

        $payload = wp_json_encode( [
            'host'        => $host,
            'key'         => $key,
            'keyLocation' => self::key_file_url(),
            'urlList'     => $urls,
        ] );

        $response = wp_remote_post( self::INDEXNOW_URL, [
            'headers' => [ 'Content-Type' => 'application/json; charset=utf-8' ],
            'body'    => $payload,
            'timeout' => 15,
        ] );

        if ( is_wp_error( $response ) ) {
            self::log_entries( $urls, 'error', 0 );
            return $response;
        }

        $code    = (int) wp_remote_retrieve_response_code( $response );
        $success = in_array( $code, [ 200, 202 ], true );
        self::log_entries( $urls, $success ? 'submitted' : 'failed', $code );

        if ( ! $success ) {
            return new WP_Error( 'indexnow_' . $code, "IndexNow returned HTTP {$code}." );
        }

        return true;
    }

    /* Log ------------------------------------------------------------------ */

    private static function log_entries( array $urls, $status, $code ) {
        $log = get_option( self::OPT_LOG, [] );
        $now = time();
        foreach ( array_reverse( $urls ) as $url ) {
            array_unshift( $log, [
                'url'    => $url,
                'status' => $status,
                'code'   => $code,
                'time'   => $now,
            ] );
        }
        update_option( self::OPT_LOG, array_slice( $log, 0, self::LOG_LIMIT ), false );
    }

    public static function get_log() {
        return get_option( self::OPT_LOG, [] );
    }

    /* Helpers -------------------------------------------------------------- */

    public static function auto_enabled() {
        // Default is OFF ('0') - user must explicitly enable auto-submit in Settings.
        return (bool) get_option( self::OPT_AUTO, '0' );
    }

    public static function indexable_types() {
        return array_values( get_post_types( [ 'public' => true ], 'names' ) );
    }

    /* AJAX handlers -------------------------------------------------------- */

    public static function ajax_submit() {
        check_ajax_referer( 'awbseo_nonce', 'nonce' );
        if ( ! current_user_can( 'manage_options' ) ) wp_send_json_error( 'Forbidden', 403 );

        $raw  = isset( $_POST['urls'] ) ? (array) $_POST['urls'] : [];
        $urls = array_filter( array_map( 'esc_url_raw', $raw ) );

        if ( empty( $urls ) ) wp_send_json_error( 'No valid URLs provided.' );

        $result = self::submit( array_values( $urls ) );
        if ( is_wp_error( $result ) ) wp_send_json_error( $result->get_error_message() );

        wp_send_json_success( [ 'submitted' => count( $urls ) ] );
    }

    public static function ajax_submit_all() {
        check_ajax_referer( 'awbseo_nonce', 'nonce' );
        if ( ! current_user_can( 'manage_options' ) ) wp_send_json_error( 'Forbidden', 403 );

        $posts = get_posts( [
            'post_type'      => self::indexable_types(),
            'post_status'    => 'publish',
            'posts_per_page' => 500,
            'fields'         => 'ids',
        ] );

        $urls = [];
        foreach ( $posts as $id ) {
            $u = get_permalink( $id );
            if ( $u ) $urls[] = $u;
        }

        if ( empty( $urls ) ) wp_send_json_error( 'No published posts found.' );

        // IndexNow allows up to 10,000 URLs per call - submit in batches of 200.
        $chunks  = array_chunk( $urls, 200 );
        $errors  = [];
        $success = 0;
        foreach ( $chunks as $chunk ) {
            $r = self::submit( $chunk );
            if ( is_wp_error( $r ) ) {
                $errors[] = $r->get_error_message();
            } else {
                $success += count( $chunk );
            }
        }

        wp_send_json_success( [
            'submitted' => $success,
            'errors'    => $errors,
            'total'     => count( $urls ),
        ] );
    }

    public static function ajax_generate_key() {
        check_ajax_referer( 'awbseo_nonce', 'nonce' );
        if ( ! current_user_can( 'manage_options' ) ) wp_send_json_error( 'Forbidden', 403 );

        $key = self::make_key();
        update_option( self::OPT_KEY, $key, false );
        // Clear log - old key is now invalid.
        update_option( self::OPT_LOG, [], false );

        wp_send_json_success( [
            'key'      => $key,
            'file_url' => home_url( '/' . $key . '.txt' ),
        ] );
    }

    public static function ajax_clear_log() {
        check_ajax_referer( 'awbseo_nonce', 'nonce' );
        if ( ! current_user_can( 'manage_options' ) ) wp_send_json_error( 'Forbidden', 403 );
        update_option( self::OPT_LOG, [], false );
        wp_send_json_success();
    }

    /* Meta box ------------------------------------------------------------- */

    public static function register_meta_box() {
        foreach ( self::indexable_types() as $pt ) {
            add_meta_box(
                'awbseo_instant_indexing',
                '⚡ Instant Indexing',
                [ __CLASS__, 'render_meta_box' ],
                $pt,
                'side',
                'high'
            );
        }
    }

    public static function render_meta_box( $post ) {
        $permalink  = get_permalink( $post->ID );
        $published  = $post->post_status === 'publish';
        $nonce      = wp_create_nonce( 'awbseo_nonce' );

        // Find last log entry for this URL.
        $last = null;
        foreach ( self::get_log() as $entry ) {
            if ( $entry['url'] === $permalink ) { $last = $entry; break; }
        }

        $green  = '#04785b';
        $red    = '#aa3535';
        $muted  = '#7c706c';
        ?>
        <div id="awbseo-ii-box" style="font-size:13px;line-height:1.5;">
            <?php if ( $last ) : ?>
                <p style="margin:0 0 8px;color:<?php echo esc_attr( $last['status'] === 'submitted' ? $green : $red ); ?>;">
                    <?php echo $last['status'] === 'submitted' ? '✓ Submitted' : ( $last['status'] === 'error' ? '✗ Network error' : '✗ Failed (HTTP ' . absint( $last['code'] ) . ')' ); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- literal strings only, code is absint ?>
                    &nbsp;·&nbsp; <?php echo esc_html( human_time_diff( $last['time'] ) ); ?> ago
                </p>
            <?php else : ?>
                <p style="margin:0 0 8px;color:<?php echo $muted; ?>;">Not yet submitted to IndexNow.</p>
            <?php endif; ?>

            <?php if ( $published && $permalink ) : ?>
                <button type="button" id="awbseo-ii-btn"
                    style="display:block;width:100%;text-align:center;cursor:pointer;"
                    class="button button-primary">
                    ⚡ Submit to IndexNow
                </button>
                <span id="awbseo-ii-msg" style="display:block;margin-top:6px;font-size:12px;color:<?php echo esc_attr( $muted ); ?>;min-height:16px;"></span>
            <?php else : ?>
                <p style="margin:0;color:<?php echo $muted; ?>;font-style:italic;font-size:12px;">
                    Publish this post to enable instant indexing.
                </p>
            <?php endif; ?>
        </div>
        <?php if ( $published && $permalink ) : ?>
        <?php
        $awb_ii_nonce    = wp_json_encode( $nonce );
        $awb_ii_url      = wp_json_encode( $permalink );
        $awb_ii_ajax_url = wp_json_encode( admin_url( 'admin-ajax.php' ) );
        $awb_ii_js       = 'var awbIINonce=' . $awb_ii_nonce . ',awbIIUrl=' . $awb_ii_url . ',awbIIAjaxUrl=' . $awb_ii_ajax_url . ';';
        $awb_ii_js      .= <<<'AWBIIBOXJS'
(function () {
    var btn = document.getElementById('awbseo-ii-btn');
    var msg = document.getElementById('awbseo-ii-msg');
    if (!btn) return;
    btn.addEventListener('click', function () {
        btn.disabled = true;
        btn.textContent = 'Submitting…';
        msg.textContent = '';
        var fd = new URLSearchParams({
            action: 'awbseo_indexnow_submit',
            nonce: awbIINonce,
            'urls[]': awbIIUrl
        });
        fetch(typeof ajaxurl !== 'undefined' ? ajaxurl : awbIIAjaxUrl, {
            method: 'POST',
            headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
            body: fd.toString()
        })
        .then(function (r) { return r.json(); })
        .then(function (res) {
            if (res.success) {
                btn.textContent = '✓ Submitted!';
                msg.style.color = '#04785b';
                msg.textContent = 'URL queued for indexing.';
            } else {
                btn.disabled = false;
                btn.textContent = '⚡ Submit to IndexNow';
                msg.style.color = '#aa3535';
                msg.textContent = res.data || 'Submission failed.';
            }
        })
        .catch(function () {
            btn.disabled = false;
            btn.textContent = '⚡ Submit to IndexNow';
            msg.style.color = '#aa3535';
            msg.textContent = 'Network error - try again.';
        });
    });
})();
AWBIIBOXJS;
        wp_add_inline_script( 'awbseo-admin', $awb_ii_js );
        ?>
        <?php endif;
    }
}