<?php
/* Define the custom boxes */
add_action('admin_menu', 'emporium_add_custom_boxes');

/* Save data entered */
add_action('save_post', 'emporium_save_custom_data');

/* Adds to Post & Page screens */
function emporium_add_custom_boxes() {
	add_meta_box( 'emporium_custom_keywords', __( 'Meta Tags', 'emporium' ), 'emporium_inner_custom_box', 'post', 'side' );
	add_meta_box( 'emporium_custom_keywords', __( 'Meta Tags', 'emporium' ), 'emporium_inner_custom_box', 'page', 'side' );
}

// Prints the inner fields for the custom post/page section
function emporium_inner_custom_box() {
	// Get stored custom meta
	global $post_id;
	$desc = ( get_post_meta($post_id, '_emporium_custom_description', true) ) ? get_post_meta($post_id, '_emporium_custom_description', true)
	: '';
	$keywords = ( get_post_meta($post_id, '_emporium_custom_keywords', true) ) ? get_post_meta($post_id, '_emporium_custom_keywords', true)
	: '';

	// Use nonce for verification
	echo '<input type="hidden" name="emporium_noncename" id="emporium_noncename" value="' .
	wp_create_nonce( 'emporium') . '" />';

	// Fields for data entry
	echo '<p><label for="emporium_custom_description">' . __('Description', 'emporium' ) . '</label><br />';
	echo '<input id="emporium_custom_description" type="text" name="_emporium_custom_description" value="' . $desc . '" size="40" />
	<label for="emporium_custom_description" class="howto">' . __('A short summary of this post or page.', 'emporium' ) . '</label></p>';

	echo '<p><label for="emporium_custom_keywords">' . __('Keywords', 'emporium' ) . '</label><br />';
	echo '<input id="emporium_custom_keywords" type="text" name="_emporium_custom_keywords" value="' . $keywords . '" size="40" />
	<label for="emporium_custom_keywords" class="howto">' . __('Separate keywords with a comma or a single space.', 'emporium') . '</label></p>';
}

/* When the post is saved, save custom data */
function emporium_save_custom_data( $post_id ) {
	// verify this came from our screen & with proper authorization,
	if ( !isset( $_POST['emporium_noncename']) || !wp_verify_nonce( $_POST['emporium_noncename'], 'emporium' ) ) return $post_id;

	// If this an autosave, don't do anything
	if ( defined('DOING_AUTOSAVE') && DOING_AUTOSAVE ) return $post_id;

	// Check permissions
	if ( $_POST['post_type'] == 'page' &&  !current_user_can( 'edit_page', $post_id ) ) return $post_id;
	elseif ( !current_user_can( 'edit_post', $post_id ) ) return $post_id;

	// Save the data
	$desc = $_POST['_emporium_custom_description'];
	$keywords = $_POST['_emporium_custom_keywords'];

	update_post_meta($post_id, '_emporium_custom_description', $desc);
	update_post_meta($post_id, '_emporium_custom_keywords', $keywords);

	return;
}
?>