Merge pull request #16 from MatthewEppelsheimer/patch-no-categories-f…

…ound

Improved shortcode category handling

lib/class.wp-publication-archive.php

@@ -238,15 +238,6 @@ public static function shortcode_handler( $atts ) {
 
 		global $post;
 
-		// Create an array of category IDs based on the categories fed in.
-		$catFilter = array();
-		$catList = explode(',', $categories);
-		foreach( $catList as $catName ){
-			$id = get_cat_id( trim( $catName ) );
-			if( 0 !== $id )
-				$catFilter[] = $id;
-		}
-
 		$pubs_per_page = apply_filters( 'wpa-pubs_per_page', 10 );
 
 		if(isset($_GET['wpa-paged'])) {
@@ -257,19 +248,33 @@ public static function shortcode_handler( $atts ) {
 			$offset = 0;
 		}
 
-		$list = '<div class="publication-archive">';
-
 		// Get publications
 		$args = array(
 			'offset' => $offset,
 			'numberposts' => $pubs_per_page,
 			'post_type' => 'publication',
 			'orderby' => 'post_date',
 			'order' => 'DESC',
-			'post_status' => 'publish',
-			'category__in' => $catFilter
+			'post_status' => 'publish'
 		);
 
+		if ( '' != $categories ) {
+			// Create an array of category IDs based on the categories fed in.
+			$catFilter = array();
+			$catList = explode(',', $categories);
+			foreach( $catList as $catName ){
+				$id = get_cat_id( trim( $catName ) );
+				if( 0 !== $id )
+					$catFilter[] = $id;
+			}
+			// if no categories matched categories in the database, report failure
+			if ( empty( $catFilter ) ) {
+				$error_msg = "<div class='publication-archive'><p>". __(' Sorry, but the categories you passed to the wp-publication-archive shortcode do not match any publication categories.' ) . "</p><p>" . __( 'You passed: ', 'wp-publication-archive' ) . "<code>$categories</code></p></div>";
+				return $error_msg;
+			}
+			$args['category'] = implode( ',', $catFilter );
+		}
+
 		if('' != $author) {
 			$args['tax_query'] = array(array(
 				'taxonomy' => 'publication-author',
@@ -282,8 +287,35 @@ public static function shortcode_handler( $atts ) {
 
 		$args['numberposts'] = -1;
 		$total_pubs = count( get_posts( $args ) );
+
+		// Report if there are no publications matching filters
+		if ( 0 == $total_pubs ) {
+			$error_msg = "<p>" . __( 'There are no publications to display' );
+			if ( '' != $author ) 
+				$error_msg .= __( ' by ' ) . "$author";
+			if ( '' != $categories ) {
+				// There is probably a better way to do this…
+				$error_msg .= __( ' categorized ' );
+				$catList = explode ( ',', $categories );
+				$catNum = count( $catList );
+				$x = 3; // number of terms necessary for grammar to require commas after each term
+				if ( $catNum > 2 ) $x = 1;
+				 for ( $i = 0; $i < $catNum; $i++ ) {
+					if ( $catNum > 1 && $i == ( $catNum - 1 ) ) $error_msg .= 'or ';
+					$error_msg .= $catList[$i];
+					if ( $i < ( $catNum - $x ) ) { 
+						$error_msg .= ', ';
+					} else if ( $i < ( $catNum - 1 ) ) { 
+						$error_msg .= ' ';
+					}
+				}
+			}
+			$error_msg .= ".</p>";
+			return $error_msg;
+		}
 
 		// Create publication list
+		$list = '<div class="publication-archive">';
 		foreach( $publications as $publication ) {
 			$pub = new WP_Publication_Archive_Item( $publication->ID, $publication->post_title, $publication->post_date );
 
@@ -358,4 +390,4 @@ public static function the_title( $title, $id ) {
 		return $title . " (Download Publication)";
 	}
 }
-?>
+?>