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class Jetpack_Testimonial_Details_Metabox {

	public function __construct() {

		if ( is_admin() ) {
			add_action( 'load-post.php',     array( $this, 'init_metabox' ) );
			add_action( 'load-post-new.php', array( $this, 'init_metabox' ) );
		}

	}

	public function init_metabox() {

		add_action( 'add_meta_boxes',        array( $this, 'add_metabox' )         );
		add_action( 'save_post',             array( $this, 'save_metabox' ), 10, 2 );

	}

	public function add_metabox() {

		add_meta_box(
			'',
			__( 'Testimonial Details', 'jetpack' ),
			array( $this, 'render_details_metabox' ),
			'jetpack-testimonial',
			'advanced',
			'default'
		);

	}

	public function render_details_metabox( $post ) {

		// Add nonce for security and authentication.
		wp_nonce_field( 'nonce_action', 'nonce' );

		// Retrieve an existing value from the database.
		$jetpack_testimonial_gravatar_email_address = get_post_meta( $post->ID, 'jetpack_testimonial_gravatar_email_address', true );
		$jetpack_testimonial_byline = get_post_meta( $post->ID, 'jetpack_testimonial_byline', true );
		$jetpack_testimonial_url = get_post_meta( $post->ID, 'jetpack_testimonial_url', true );

		// Set default values.
		if( empty( $jetpack_testimonial_gravatar_email_address ) ) $jetpack_testimonial_gravatar_email_address = '';
		if( empty( $jetpack_testimonial_byline ) ) $jetpack_testimonial_byline = '';
		if( empty( $jetpack_testimonial_url ) ) $jetpack_testimonial_url = '';

		// Form fields.
		echo '<table class="form-table">';

		echo '	<tr>';
		echo '		<th><label for="jetpack_testimonial_gravatar_email_address" class="jetpack_testimonial_gravatar_email_address_label">' . __( 'Gravatar Email Address', 'jetpack' ) . '</label></th>';
		echo '		<td>';
		echo '			<input type="email" id="jetpack_testimonial_gravatar_email_address" name="jetpack_testimonial_gravatar_email_address" class="jetpack_testimonial_gravatar_email_address_field" placeholder="' . esc_attr__( 'user@domain.com', 'jetpack' ) . '" value="' . esc_attr__( $jetpack_testimonial_gravatar_email_address ) . '">';
		echo '			<p class="description">' . __( 'Enter in an e-mail address, to use a <a href="https://gravatar.com" target="_blank">Gravatar</a>, instead of using the "Featured Image".', 'jetpack' ) . '</p>';
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="jetpack_testimonial_byline" class="jetpack_testimonial_byline_label">' . __( 'Byline', 'jetpack' ) . '</label></th>';
		echo '		<td>';
		echo '			<input type="text" id="jetpack_testimonial_byline" name="jetpack_testimonial_byline" class="jetpack_testimonial_byline_field" placeholder="' . esc_attr__( 'Job Title of Company', 'jetpack' ) . '" value="' . esc_attr__( $jetpack_testimonial_byline ) . '">';
		echo '			<p class="description">' . __( 'Enter a byline for the customer giving this testimonial (for example: "CEO of Company").', 'jetpack' ) . '</p>';
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="jetpack_testimonial_url" class="jetpack_testimonial_url_label">' . __( 'URL', 'jetpack' ) . '</label></th>';
		echo '		<td>';
		echo '			<input type="url" id="jetpack_testimonial_url" name="jetpack_testimonial_url" class="jetpack_testimonial_url_field" placeholder="' . esc_attr__( 'https://example.com', 'jetpack' ) . '" value="' . esc_attr__( $jetpack_testimonial_url ) . '">';
		echo '			<p class="description">' . __( 'Enter a URL that applies to this customer (for example: https://jetpack.com/).', 'jetpack' ) . '</p>';
		echo '		</td>';
		echo '	</tr>';

		echo '</table>';

	}

	public function save_metabox( $post_id, $post ) {

		// Add nonce for security and authentication.
		$nonce_name   = isset( $_POST['nonce'] ) ? $_POST['nonce'] : '';
		$nonce_action = 'nonce_action';

		// Check if a nonce is set.
		if ( ! isset( $nonce_name ) )
			return;

		// Check if a nonce is valid.
		if ( ! wp_verify_nonce( $nonce_name, $nonce_action ) )
			return;

		// Check if the user has permissions to save data.
		if ( ! current_user_can( 'edit_post', $post_id ) )
			return;

		// Check if it's not an autosave.
		if ( wp_is_post_autosave( $post_id ) )
			return;

		// Check if it's not a revision.
		if ( wp_is_post_revision( $post_id ) )
			return;

		// Sanitize user input.
		$new_jetpack_testimonial_gravatar_email_address = isset( $_POST[ 'jetpack_testimonial_gravatar_email_address' ] ) ? sanitize_email( $_POST[ 'jetpack_testimonial_gravatar_email_address' ] ) : '';
		$new_jetpack_testimonial_byline = isset( $_POST[ 'jetpack_testimonial_byline' ] ) ? sanitize_text_field( $_POST[ 'jetpack_testimonial_byline' ] ) : '';
		$new_jetpack_testimonial_url = isset( $_POST[ 'jetpack_testimonial_url' ] ) ? esc_url( $_POST[ 'jetpack_testimonial_url' ] ) : '';

		// Update the meta field in the database.
		update_post_meta( $post_id, 'jetpack_testimonial_gravatar_email_address', $new_jetpack_testimonial_gravatar_email_address );
		update_post_meta( $post_id, 'jetpack_testimonial_byline', $new_jetpack_testimonial_byline );
		update_post_meta( $post_id, 'jetpack_testimonial_url', $new_jetpack_testimonial_url );

	}

}

new Jetpack_Testimonial_Details_Metabox;