fix bug causing edit tracks component to crash

admin/components/tracks/edittracks.html

@@ -3,20 +3,20 @@
         <h2>Editing: Tracks</h2>
         <a id="add-track"
            class="button new"
-           href="/admin/release/{{.ID}}/addtrack"
-           hx-get="/admin/release/{{.ID}}/addtrack"
+           href="/admin/release/{{.Release.ID}}/addtrack"
+           hx-get="/admin/release/{{.Release.ID}}/addtrack"
            hx-target="body"
            hx-swap="beforeend"
         >Add</a>
     </header>
 
-    <form action="/api/v1/music/{{.ID}}/tracks">
+    <form action="/api/v1/music/{{.Release.ID}}/tracks">
         <ul>
-            {{range $i, $track := .Tracks}}
+            {{range $i, $track := .Release.Tracks}}
             <li class="track" data-track="{{$track.ID}}" data-title="{{$track.Title}}" data-number="{{$track.Add $i 1}}" draggable="true">
                 <div>
                     <p class="track-name">
-                        <span class="track-number">{{$track.Add $i 1}}</span>
+                        <span class="track-number">{{.Add $i 1}}</span>
                         {{$track.Title}}
                     </p>
                     <a class="delete">Delete</a>

admin/releasehttp.go

@@ -145,7 +145,16 @@ func serveEditLinks(release *model.Release) http.Handler {
 func serveEditTracks(release *model.Release) http.Handler {
     return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
         w.Header().Set("Content-Type", "text/html")
-        err := components["edittracks"].Execute(w, release)
+
+        type editTracksData struct {
+            Release *model.Release
+            Add func(a int, b int) int
+        }
+
+        err := components["edittracks"].Execute(w, editTracksData{
+            Release: release,
+            Add: func(a, b int) int { return a + b },
+        })
         if err != nil {
             fmt.Printf("Error rendering edit tracks component for %s: %s\n", release.ID, err)
             http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)

model/track.go

@@ -12,6 +12,8 @@ type (
 		Description string  `json:"description"`
         Lyrics      string  `json:"lyrics" db:"lyrics"`
 		PreviewURL  string  `json:"previewURL" db:"preview_url"`
+
+        Number      int
 	}
 )