<?php
/**
 * Load More Posts via AJAX.
 *
 * @package Doo
 */

/**
 * Processing data query for load more
 *
 * @param string $method Processing method $wp_query.
 * @param array  $data Data array.
 */
function vs_load_more_query_data( $method = 'get', $data = array() ) {
  global $wp_query;

  $output = array();

  $vars = array(
    'in_the_loop',
    'is_single',
    'is_page',
    'is_archive',
    'is_author',
    'is_category',
    'is_tag',
    'is_tax',
    'is_home',
    'is_singular',
  );

  if ( 'get' === $method ) {
    $output = $data;
  }

  foreach ( $vars as $variable ) {
    if ( ! isset( $wp_query->$variable ) ) {
      continue;
    }
    if ( 'get' === $method ) {
      $output[ $variable ] = $wp_query->$variable;
    }
    if ( ! isset( $data[ $variable ] ) ) {
      continue;
    }
    if ( 'init' === $method ) {
      $wp_query->$variable = $data[ $variable ];
    }
  }

  if ( 'get' === $method ) {
    $output = apply_filters( 'ajax_query_args', $output );
  }

  return wp_json_encode( $output );
}

/**
 * Localize the main theme scripts.
 */
function vs_load_more_js() {
  global $wp_query;

  if ( $wp_query->max_num_pages <= 1 ) {
    return;
  }

  if ( is_home() ) {
    $pagination_type = get_theme_mod( 'homepage_pagination_type', 'load-more' );

  } else {
    $pagination_type = get_theme_mod( 'archive_pagination_type', 'load-more' );
  }

  if ( in_array( $pagination_type, array( 'load-more', 'infinite' ), true ) ) {

    // Pagination type.
    $wp_query->infinite = 'infinite' === $pagination_type ? true : false;

    if ( is_home() ) {
      // Theme data.
      $data = array(
        'location'      => 'homepage',
        'infinite_load' => $wp_query->infinite,
        'query_vars'    => $wp_query->query_vars,
      );
    } else {
      // Theme data.
      $data = array(
        'location'      => 'archive',
        'infinite_load' => $wp_query->infinite,
        'query_vars'    => $wp_query->query_vars,
      );
    }
    
    // Pagination Type.
    $ajax_type = version_compare( get_bloginfo( 'version' ), '4.7', '>=' ) ? 'ajax_restapi' : 'ajax';
    $ajax_type = apply_filters( 'ajax_load_more_method', $ajax_type );

    $args = array(
      'type'           => $ajax_type,
      'nonce'          => wp_create_nonce(),
      'url'            => admin_url( 'admin-ajax.php' ),
      'rest_url'       => esc_url( get_rest_url( null, '/vs/v1/more-posts' ) ),
      'posts_per_page' => get_query_var( 'posts_per_page' ),
      'query_data'     => vs_load_more_query_data( 'get', $data ),
      'translation'    => array(
        'load_more' => esc_html__( 'Load More', 'doo' ),
      ),
    );

    wp_localize_script( 'vs-scripts', 'vs_ajax_pagination', $args );
  }
}

add_action( 'wp_enqueue_scripts', 'vs_load_more_js' );

/**
 * Get More Posts
 */
function vs_load_more_posts() {

  $posts_end = false;

  // Response default.
  $response = array(
    'page'           => 2,
    'posts_per_page' => 10,
  );

  if ( wp_doing_ajax() ) {
    check_ajax_referer();
  }

  // Set response values of ajax query.
  if ( isset( $_POST['page'] ) && $_POST['page'] ) { // Input var ok.
    $response['page'] = sanitize_key( $_POST['page'] ); // Input var ok; sanitization ok.
  }
  if ( isset( $_POST['posts_per_page'] ) && $_POST['posts_per_page'] ) { // Input var ok.
    $response['posts_per_page'] = sanitize_key( $_POST['posts_per_page'] ); // Input var ok; sanitization ok.
  }
  if ( isset( $_POST['query_data'] ) && $_POST['query_data'] ) { // Input var ok.
    $response['query_data'] = $_POST['query_data']; // Input var ok; sanitization ok.
  }

  // Init Data.
  $query_data = json_decode( stripslashes( $response['query_data'] ), true );

  // Set Query Vars.
  $query_vars = array_merge( (array) $query_data['query_vars'], array(
    'paged'          => (int) $response['page'],
    'posts_per_page' => (int) $response['posts_per_page'],
  ) );

  // Suppress filtering for wp authors.
  if ( $query_data['is_author'] && $query_vars['author'] ) {
    $query_vars['suppress_filters'] = true;
  }

  // Get Posts.
  ob_start();

  $the_query = new WP_Query( $query_vars );

  $global_name = 'wp_query';

  $GLOBALS[ $global_name ] = $the_query;

  vs_load_more_query_data( 'init', $query_data );

  if ( $the_query->have_posts() ) :

    // Set query vars, so that we can get them across all templates.
    set_query_var( 'vs_query', $query_data );

    // Get total number of posts.
    $total = $the_query->post_count;

    while ( $the_query->have_posts() ) :
      $the_query->the_post();

      // Start counting posts.
      $current = $the_query->current_post + 1 + $query_vars['posts_per_page'] * $query_vars['paged'] - $query_vars['posts_per_page'];

      // Check End of posts.
      if ( $the_query->found_posts - $current <= 0 ) {
        $posts_end = true;
      }

      // Get content template part.
      get_template_part( 'template-parts/content-homepage' );

    endwhile;

  endif;

  wp_reset_postdata();

  $content = ob_get_clean();

  if ( ! $content ) {
    $posts_end = true;
  }

  // Return Result.
  $result = array(
    'posts_end' => $posts_end,
    'content'   => $content,
  );

  return $result;
}

/**
 * AJAX Load More
 */
function vs_ajax_load_more() {

  // Check Nonce.
  check_ajax_referer();

  // Get Posts.
  $data = vs_load_more_posts();

  // Return Result.
  wp_send_json_success( $data );

}

add_action( 'wp_ajax_vs_ajax_load_more', 'vs_ajax_load_more' );
add_action( 'wp_ajax_nopriv_vs_ajax_load_more', 'vs_ajax_load_more' );


/**
 * More Posts API Response
 *
 * @param array $request REST API Request.
 */
function vs_more_posts_restapi( $request ) {

  // Get Data.
  $data = array(
    'success' => true,
    'data'    => vs_load_more_posts(),
  );

  // Return Result.
  return rest_ensure_response( $data );
}

/**
 * Register REST More Posts Routes
 */
function vs_register_more_posts_route() {

  register_rest_route(
    'vs/v1', '/more-posts', array(
      'methods'  => WP_REST_Server::CREATABLE,
      'callback' => 'vs_more_posts_restapi',
    )
  );
}
add_action( 'rest_api_init', 'vs_register_more_posts_route' );