implement moving of tracks in queue

src/commands.rs

@@ -55,6 +55,7 @@ impl CommandManager {
 
         self.register_command("search", None);
         self.register_command("move", None);
+        self.register_command("shift", None);
         self.register_command("play", None);
         self.register_command("queue", None);
         self.register_command("delete", None);
@@ -315,6 +316,9 @@ impl CommandManager {
         kb.insert("h".into(), "move left".into());
         kb.insert("l".into(), "move right".into());
 
+        kb.insert("Shift+Up".into(), "shift up".into());
+        kb.insert("Shift+Down".into(), "shift down".into());
+
         kb
     }
 

src/ui/listview.rs

@@ -20,6 +20,7 @@ pub struct ListView<I: 'static + ListItem> {
     last_size: Vec2,
     scrollbar: ScrollBase,
     queue: Arc<Queue>,
+    shiftable: bool,
 }
 
 impl<I: ListItem> ListView<I> {
@@ -31,9 +32,15 @@ impl<I: ListItem> ListView<I> {
             last_size: Vec2::new(0, 0),
             scrollbar: ScrollBase::new(),
             queue,
+            shiftable: false,
         }
     }
 
+    pub fn shiftable(mut self) -> Self {
+        self.shiftable = true;
+        self
+    }
+
     pub fn get_selected_index(&self) -> usize {
         self.selected
     }
@@ -48,6 +55,11 @@ impl<I: ListItem> ListView<I> {
         let new = self.selected as i32 + delta;
         self.move_focus_to(max(new, 0) as usize);
     }
+
+    pub fn swap(&mut self, a: usize, b: usize) {
+        let mut content = self.content.write().expect("can't writelock content");
+        content.swap(a, b);
+    }
 }
 
 impl<I: ListItem> View for ListView<I> {
@@ -196,23 +208,31 @@ impl<I: ListItem> ViewExt for ListView<I> {
             return Ok(CommandResult::Consumed(None));
         }
 
-        if cmd == "move" {
+        if cmd == "move" || cmd == "shift" {
             if let Some(dir) = args.get(0) {
-                let amount: i32 = args
+                let amount: usize = args
                     .get(1)
                     .unwrap_or(&"1".to_string())
                     .parse()
                     .map_err(|e| format!("{:?}", e))?;
 
+                let shift = cmd == "shift" && self.shiftable;
+                let selected = self.selected;
                 let len = self.content.read().unwrap().len();
 
                 if dir == "up" && self.selected > 0 {
-                    self.move_focus(-amount);
+                    if shift {
+                        self.swap(selected, selected.saturating_sub(amount));
+                    }
+                    self.move_focus(-(amount as i32));
                     return Ok(CommandResult::Consumed(None));
                 }
 
                 if dir == "down" && self.selected < len.saturating_sub(1) {
-                    self.move_focus(amount);
+                    if shift {
+                        self.swap(selected, min(selected + amount as usize, len - 1));
+                    }
+                    self.move_focus(amount as i32);
                     return Ok(CommandResult::Consumed(None));
                 }
             }

src/ui/queue.rs

@@ -22,7 +22,7 @@ pub struct QueueView {
 
 impl QueueView {
     pub fn new(queue: Arc<Queue>, playlists: Arc<Playlists>) -> QueueView {
-        let list = ListView::new(queue.queue.clone(), queue.clone());
+        let list = ListView::new(queue.queue.clone(), queue.clone()).shiftable();
 
         QueueView {
             list,