From 328957d6f7b3be53813585ec39878adb6ceee28f Mon Sep 17 00:00:00 2001
From: Jonathan Bernard <jdbernard@gmail.com>
Date: Wed, 16 Mar 2016 02:14:11 -0500
Subject: [PATCH] Fixed joins in getMediaFilesWhere to use outer joins when not
 filtering by the joined table.

---
 .../com/jdbernard/wdiwtlt/db/ORM.groovy       | 51 ++++++++++++-------
 1 file changed, 33 insertions(+), 18 deletions(-)

diff --git a/core/src/main/groovy/com/jdbernard/wdiwtlt/db/ORM.groovy b/core/src/main/groovy/com/jdbernard/wdiwtlt/db/ORM.groovy
index a503262..736863d 100644
--- a/core/src/main/groovy/com/jdbernard/wdiwtlt/db/ORM.groovy
+++ b/core/src/main/groovy/com/jdbernard/wdiwtlt/db/ORM.groovy
@@ -414,34 +414,40 @@ public class ORM {
     public List<MediaFile> getMediaFilesWhere(Map params) {
         def query = new StringBuilder()
         def sqlParams = []
+        def joins = []
         def orderClauses = [] as LinkedList
         def whereClauses = []
 
+        def newJoin
         query.append('SELECT mf.* FROM media_files mf ')
 
         if (params.artistId || params.playlistId) {
-            query.append(' JOIN artists_media_files armf ON ')
-                 .append(' mf.id = armf.media_file_id ')
+            joins << (newJoin = [
+                table: 'artists_media_files armf',
+                clauses: ['mf.id = armf.media_file_id']])
+
+            if (params.artistId) {
+                newJoin.clauses << 'armf.artist_id = ?'
+                sqlParams << params.artistId }
+            else newJoin.type = 'LEFT'
+
             orderClauses << 'armf.artist_id ASC' }
 
-        if (params.artistId) {
-            query.append(' AND armf.artist_id = ? ')
-            sqlParams << params.artistId }
-
         if (params.albumId || params.artistId || params.playlistId) {
-            query.append(' JOIN albums_media_files almf ON ')
-                 .append(' mf.id = almf.media_file_id ')
+            joins << (newJoin = [
+                table: 'albums_media_files almf',
+                clauses: ['mf.id = almf.media_file_id']])
 
+            if (params.albumId) {
+                newJoin.clauses << 'almf.album_id = ?'
+                sqlParams << params.albumId }
+            else newJoin.type = 'LEFT'
             orderClauses << 'almf.album_id ASC' }
 
-        if (params.albumId) {
-            query.append(' AND almf.album_id = ? ')
-            sqlParams << params.albumId }
-
         if (params.playlistId) {
-            query.append(' JOIN playlists_media_files pmf ON ')
-            query.append(' pmf.media_file_id = mf.id AND ')
-            query.append(' pmf.playlist_id = ?')
+            joins << (newJoin = [
+                table: 'playlists_media_files pmf',
+                clauses: ['pmf.media_file_id = mf.id', 'pmf.playlist_id = ?']])
             orderClauses.addFirst('pmf.position')
             sqlParams << params.playlistId }
 
@@ -468,14 +474,23 @@ public class ORM {
         if (params.tags) {
             params.tags.eachWithIndex { tag, idx ->
                 String L = "mft${idx}";
-                query.append(" JOIN media_files_tags $L ON ")
-                     .append(" ${L}.media_file_id = mf.id AND ${L}.tag_id =  ?")
-
+                joins << (newJoin = [
+                    table: "media_files_tags $L",
+                    clauses: ["${L}.media_file_id = mf.id",
+                              "${L}.tag_id = ?"]])
                 sqlParams << tag.id } }
 
         orderClauses << 'mf.disc_number'
         orderClauses << 'mf.track_number'
 
+        joins.each { j ->
+            if (j.type) query.append(' ').append(j.type).append(' ')
+
+            query.append(' JOIN ')
+                 .append(j.table)
+                 .append(' ON ')
+                 .append(j.clauses.join(' AND ')) }
+
         if (whereClauses)
             query.append(' WHERE ').append(whereClauses.join(' AND '))