Drag and drop moves tracks in queue

For some reason we're not seeing the insert indicator, and I can't
figure out why.

Persephone.xcodeproj/project.pbxproj

@@ -112,6 +112,7 @@
 		E4B11BC22275EE410075461B /* AlbumListActions.swift in Sources */ = {isa = PBXBuildFile; fileRef = E4B11BC12275EE410075461B /* AlbumListActions.swift */; };
 		E4C8B53C22342005009A20F3 /* PreferencesWindowController.swift in Sources */ = {isa = PBXBuildFile; fileRef = E4C8B53B22342005009A20F3 /* PreferencesWindowController.swift */; };
 		E4C8B53E22349002009A20F3 /* MPDIdle.swift in Sources */ = {isa = PBXBuildFile; fileRef = E4C8B53D22349002009A20F3 /* MPDIdle.swift */; };
+		E4D3BFA622B419C000C56F48 /* QueueViewController+NSOutlineViewDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E4D3BFA522B419C000C56F48 /* QueueViewController+NSOutlineViewDelegate.swift */; };
 		E4E7A6AD22AAAF98006D566C /* AlbumDetailView+NSTableViewDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E4E7A6AC22AAAF98006D566C /* AlbumDetailView+NSTableViewDelegate.swift */; };
 		E4E8CC902204EC7F0024217A /* Delegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E4E8CC8F2204EC7F0024217A /* Delegate.swift */; };
 		E4E8CC922204F4B80024217A /* QueueViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = E4E8CC912204F4B80024217A /* QueueViewController.swift */; };
@@ -317,6 +318,7 @@
 		E4B11BC12275EE410075461B /* AlbumListActions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AlbumListActions.swift; sourceTree = "<group>"; };
 		E4C8B53B22342005009A20F3 /* PreferencesWindowController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PreferencesWindowController.swift; sourceTree = "<group>"; };
 		E4C8B53D22349002009A20F3 /* MPDIdle.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MPDIdle.swift; sourceTree = "<group>"; };
+		E4D3BFA522B419C000C56F48 /* QueueViewController+NSOutlineViewDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "QueueViewController+NSOutlineViewDelegate.swift"; sourceTree = "<group>"; };
 		E4E7A6AC22AAAF98006D566C /* AlbumDetailView+NSTableViewDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "AlbumDetailView+NSTableViewDelegate.swift"; sourceTree = "<group>"; };
 		E4E8CC8F2204EC7F0024217A /* Delegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Delegate.swift; sourceTree = "<group>"; };
 		E4E8CC912204F4B80024217A /* QueueViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = QueueViewController.swift; sourceTree = "<group>"; };
@@ -694,6 +696,7 @@
 				E47E2FD022205C4600F747E6 /* MainSplitViewController.swift */,
 				E4405191227644340090CD6F /* MPDServerController.swift */,
 				E4E8CC912204F4B80024217A /* QueueViewController.swift */,
+				E4D3BFA522B419C000C56F48 /* QueueViewController+NSOutlineViewDelegate.swift */,
 				E4B11BB52275374B0075461B /* UserNotificationsController.swift */,
 				E465049921E94DF500A70F4C /* WindowController.swift */,
 			);
@@ -921,6 +924,7 @@
 				E4B11BB62275374B0075461B /* UserNotificationsController.swift in Sources */,
 				E4B11B68226A4FA00075461B /* QueueState.swift in Sources */,
 				E4928E0B2218D62A001D4BEA /* CGColor.swift in Sources */,
+				E4D3BFA622B419C000C56F48 /* QueueViewController+NSOutlineViewDelegate.swift in Sources */,
 				E4405196227879960090CD6F /* MPDActions.swift in Sources */,
 				E4405192227644340090CD6F /* MPDServerController.swift in Sources */,
 				E4C8B53E22349002009A20F3 /* MPDIdle.swift in Sources */,

Persephone/Controllers/QueueViewController+NSOutlineViewDelegate.swift

@@ -0,0 +1,87 @@
+//
+//  QueueViewController+NSOutlineViewDelegate.swift
+//  Persephone
+//
+//  Created by Daniel Barber on 2019/6/14.
+//  Copyright © 2019 Dan Barber. All rights reserved.
+//
+
+import AppKit
+
+extension QueueViewController: NSOutlineViewDelegate {
+  func outlineView(
+    _ outlineView: NSOutlineView,
+    selectionIndexesForProposedSelection proposedSelectionIndexes: IndexSet
+    ) -> IndexSet {
+    if proposedSelectionIndexes.contains(0) {
+      return IndexSet()
+    } else {
+      return proposedSelectionIndexes
+    }
+  }
+
+  func outlineView(_ outlineView: NSOutlineView, viewFor tableColumn: NSTableColumn?, item: Any) -> NSView? {
+    if let queueItem = item as? QueueItem {
+      switch tableColumn?.identifier.rawValue {
+        case "songTitleColumn":
+          return cellForSongTitle(outlineView, with: queueItem)
+        case "songArtistColumn":
+          return cellForSongArtist(outlineView, with: queueItem)
+        default:
+          return nil
+      }
+    } else if tableColumn?.identifier.rawValue == "songTitleColumn" {
+      return cellForQueueHeading(outlineView)
+    } else {
+      return nil
+    }
+  }
+
+  func outlineViewSelectionDidChange(_ notification: Notification) {
+    if queueView.selectedRow >= 1 {
+      let queueItem = dataSource.queue[queueView.selectedRow - 1]
+
+      App.store.dispatch(SetSelectedQueueItem(selectedQueueItem: queueItem))
+    } else {
+      App.store.dispatch(SetSelectedQueueItem(selectedQueueItem: nil))
+    }
+  }
+
+  func cellForSongTitle(_ outlineView: NSOutlineView, with queueItem: QueueItem) -> NSView {
+    let cellView = outlineView.makeView(
+      withIdentifier: .queueSongTitle,
+      owner: self
+      ) as! QueueSongTitleView
+
+    cellView.setQueueSong(queueItem, queueIcon: dataSource.queueIcon)
+
+    return cellView
+  }
+
+  func cellForSongArtist(_ outlineView: NSOutlineView, with queueItem: QueueItem) -> NSView {
+    let cellView = outlineView.makeView(
+      withIdentifier: .queueSongArtist,
+      owner: self
+      ) as! NSTableCellView
+
+    cellView.textField?.stringValue = queueItem.song.artist
+    if queueItem.isPlaying {
+      cellView.textField?.font = .systemFontBold
+    } else {
+      cellView.textField?.font = .systemFontRegular
+    }
+
+    return cellView
+  }
+
+  func cellForQueueHeading(_ outlineView: NSOutlineView) -> NSView {
+    let cellView = outlineView.makeView(
+      withIdentifier: .queueHeading,
+      owner: self
+      ) as! NSTableCellView
+
+    cellView.textField?.stringValue = "QUEUE"
+
+    return cellView
+  }
+}

Persephone/Controllers/QueueViewController.swift

@@ -9,8 +9,7 @@
 import AppKit
 import ReSwift
 
-class QueueViewController: NSViewController,
+class QueueViewController: NSViewController {
-                           NSOutlineViewDelegate {
   var dataSource = QueueDataSource()
 
   @IBOutlet var queueView: NSOutlineView!
@@ -23,8 +22,10 @@ class QueueViewController: NSViewController,
       $0.select { $0.queueState }
     }
 
-    queueView.dataSource = dataSource
+//    queueView.dataSource = dataSource
     queueView.columnAutoresizingStyle = .sequentialColumnAutoresizingStyle
+    queueView.registerForDraggedTypes([REORDER_PASTEBOARD_TYPE])
+    queueView.draggingDestinationFeedbackStyle = .regular
   }
 
   override func keyDown(with event: NSEvent) {
@@ -64,81 +65,31 @@ class QueueViewController: NSViewController,
       App.store.dispatch(MPDRemoveTrack(queuePos: queuePos))
     }
   }
+}
 
-  func outlineView(
+extension QueueViewController: NSOutlineViewDataSource {
-    _ outlineView: NSOutlineView,
+  func outlineView(_ outlineView: NSOutlineView, numberOfChildrenOfItem item: Any?) -> Int {
-    selectionIndexesForProposedSelection proposedSelectionIndexes: IndexSet
+    return dataSource.outlineView(outlineView, numberOfChildrenOfItem: item)
-  ) -> IndexSet {
-    if proposedSelectionIndexes.contains(0) {
-      return IndexSet()
-    } else {
-      return proposedSelectionIndexes
-    }
   }
 
-  func outlineView(_ outlineView: NSOutlineView, viewFor tableColumn: NSTableColumn?, item: Any) -> NSView? {
+  func outlineView(_ outlineView: NSOutlineView, isItemExpandable item: Any) -> Bool {
-    if let queueItem = item as? QueueItem {
+    return dataSource.outlineView(outlineView, isItemExpandable: item)
-      switch tableColumn?.identifier.rawValue {
-      case "songTitleColumn":
-        return cellForSongTitle(outlineView, with: queueItem)
-      case "songArtistColumn":
-        return cellForSongArtist(outlineView, with: queueItem)
-      default:
-        return nil
-      }
-    } else if tableColumn?.identifier.rawValue == "songTitleColumn" {
-      return cellForQueueHeading(outlineView)
-    } else {
-      return nil
-    }
   }
 
-  func outlineViewSelectionDidChange(_ notification: Notification) {
+  func outlineView(_ outlineView: NSOutlineView, child index: Int, ofItem item: Any?) -> Any {
-    if queueView.selectedRow >= 1 {
+    return dataSource.outlineView(outlineView, child: index, ofItem: item)
-      let queueItem = dataSource.queue[queueView.selectedRow - 1]
-
-      App.store.dispatch(SetSelectedQueueItem(selectedQueueItem: queueItem))
-    } else {
-      App.store.dispatch(SetSelectedQueueItem(selectedQueueItem: nil))
-    }
   }
 
-  func cellForSongTitle(_ outlineView: NSOutlineView, with queueItem: QueueItem) -> NSView {
+  func outlineView(_ outlineView: NSOutlineView, pasteboardWriterForItem item: Any) -> NSPasteboardWriting? {
-    let cellView = outlineView.makeView(
+    return dataSource.outlineView(outlineView, pasteboardWriterForItem: item)
-      withIdentifier: .queueSongTitle,
-      owner: self
-    ) as! QueueSongTitleView
-
-    cellView.setQueueSong(queueItem, queueIcon: dataSource.queueIcon)
-
-    return cellView
   }
 
-  func cellForSongArtist(_ outlineView: NSOutlineView, with queueItem: QueueItem) -> NSView {
+  func outlineView(_ outlineView: NSOutlineView, validateDrop info: NSDraggingInfo, proposedItem item: Any?, proposedChildIndex index: Int) -> NSDragOperation {
-    let cellView = outlineView.makeView(
+    return dataSource.outlineView(outlineView, validateDrop: info, proposedItem: item, proposedChildIndex: index)
-      withIdentifier: .queueSongArtist,
-      owner: self
-    ) as! NSTableCellView
-
-    cellView.textField?.stringValue = queueItem.song.artist
-    if queueItem.isPlaying {
-      cellView.textField?.font = .systemFontBold
-    } else {
-      cellView.textField?.font = .systemFontRegular
-    }
-
-    return cellView
   }
 
-  func cellForQueueHeading(_ outlineView: NSOutlineView) -> NSView {
+  func outlineView(_ outlineView: NSOutlineView, acceptDrop info: NSDraggingInfo, item: Any?, childIndex index: Int) -> Bool {
-    let cellView = outlineView.makeView(
+    return dataSource.outlineView(outlineView, acceptDrop: info, item: item, childIndex: index)
-      withIdentifier: .queueHeading,
-      owner: self
-    ) as! NSTableCellView
-
-    cellView.textField?.stringValue = "QUEUE"
-
-    return cellView
   }
 }
 

Persephone/DataSources/QueueDataSource.swift

@@ -8,6 +8,8 @@
 
 import AppKit
 
+let REORDER_PASTEBOARD_TYPE = NSPasteboard.PasteboardType("me.danbarber.persephone")
+
 class QueueDataSource: NSObject, NSOutlineViewDataSource {
   var queue: [QueueItem] = []
   var queueIcon: NSImage? = nil
@@ -35,7 +37,43 @@ class QueueDataSource: NSObject, NSOutlineViewDataSource {
     if index > 0 {
       return queue[index - 1]
     } else {
-      return false
+      return ""
     }
   }
+
+  func outlineView(_ outlineView: NSOutlineView, pasteboardWriterForItem item: Any) -> NSPasteboardWriting? {
+    guard let queueItem = item as? QueueItem
+      else { return nil }
+
+    let pbItem = NSPasteboardItem()
+
+    pbItem.setPropertyList(["queuePos": queueItem.queuePos], forType: REORDER_PASTEBOARD_TYPE)
+
+    return pbItem
+  }
+
+  func outlineView(_ outlineView: NSOutlineView, validateDrop info: NSDraggingInfo, proposedItem item: Any?, proposedChildIndex index: Int) -> NSDragOperation {
+    guard let draggingTypes = info.draggingPasteboard.types,
+      draggingTypes.contains(REORDER_PASTEBOARD_TYPE),
+      index >= 0
+      else { return [] }
+
+    return .move
+  }
+
+  func outlineView(_ outlineView: NSOutlineView, acceptDrop info: NSDraggingInfo, item: Any?, childIndex index: Int) -> Bool {
+    var newQueuePos = index - 1
+
+    guard let payload = info.draggingPasteboard.propertyList(forType: REORDER_PASTEBOARD_TYPE) as? [String: Int],
+      let queuePos = payload["queuePos"]
+      else { return false }
+
+    if newQueuePos > queuePos { newQueuePos -= 1 }
+
+    guard queuePos != newQueuePos else { return false }
+
+    App.store.dispatch(MPDMoveSongInQueue(oldQueuePos: queuePos, newQueuePos: newQueuePos))
+
+    return true
+  }
 }

Persephone/MPDClient/Extensions/MPDClient+Command.swift

@@ -69,6 +69,12 @@ extension MPDClient {
         else { return }
       sendRemoveSong(at: queuePos)
 
+    case .moveSongInQueue:
+      guard let oldQueuePos = userData["oldQueuePos"] as? Int,
+        let newQueuePos = userData["newQueuePos"] as? Int
+        else { return }
+      sendMoveSongInQueue(at: oldQueuePos, to: newQueuePos)
+
     // Album commands
     case .fetchAllAlbums:
       allAlbums()

Persephone/MPDClient/Extensions/MPDClient+Queue.swift

@@ -30,6 +30,10 @@ extension MPDClient {
     enqueueCommand(command: .removeSong, userData: ["queuePos": queuePos])
   }
 
+  func moveSongInQueue(at queuePos: Int, to newQueuePos: Int) {
+    enqueueCommand(command: .moveSongInQueue, userData: ["oldQueuePos": queuePos, "newQueuePos": newQueuePos])
+  }
+
   func sendPlayTrack(at queuePos: Int) {
     mpd_run_play_pos(self.connection, UInt32(queuePos))
   }
@@ -64,4 +68,8 @@ extension MPDClient {
   func sendRemoveSong(at queuePos: Int) {
     mpd_run_delete(self.connection, UInt32(queuePos))
   }
+
+  func sendMoveSongInQueue(at oldQueuePos: Int, to newQueuePos: Int) {
+    mpd_run_move(self.connection, UInt32(oldQueuePos), UInt32(newQueuePos))
+  }
 }

Persephone/MPDClient/Models/MPDCommand.swift

@@ -33,6 +33,7 @@ extension MPDClient {
     case replaceQueue
     case appendSong
     case removeSong
+    case moveSongInQueue
 
     // Album commands
     case fetchAllAlbums

Persephone/Models/QueueItem.swift

@@ -6,7 +6,7 @@
 //  Copyright © 2019 Dan Barber. All rights reserved.
 //
 
-import Foundation
+import AppKit
 
 struct QueueItem: Equatable {
   var song: Song

Persephone/Resources/Base.lproj/Main.storyboard

@@ -574,7 +574,7 @@
         <scene sceneID="QcX-dC-cTZ">
             <objects>
                 <viewController id="KIP-rq-4dM" customClass="QueueViewController" customModule="Persephone" customModuleProvider="target" sceneMemberID="viewController">
-                    <splitView key="view" wantsLayer="YES" dividerStyle="thin" id="84I-w3-Mxl">
+                    <splitView key="view" dividerStyle="thin" id="84I-w3-Mxl">
                         <rect key="frame" x="0.0" y="0.0" width="328" height="548"/>
                         <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMinY="YES"/>
                         <subviews>
@@ -713,6 +713,7 @@
                                             </tableColumns>
                                             <connections>
                                                 <action trigger="doubleAction" selector="playTrack:" target="KIP-rq-4dM" id="opa-6G-OW0"/>
+                                                <outlet property="dataSource" destination="KIP-rq-4dM" id="AL2-j1-SVE"/>
                                                 <outlet property="delegate" destination="KIP-rq-4dM" id="60F-6x-bUE"/>
                                                 <outlet property="menu" destination="dYA-Jm-eOa" id="9s2-7K-tVx"/>
                                             </connections>

Persephone/State/Actions/MPDActions.swift

@@ -18,6 +18,11 @@ struct MPDPrevTrackAction: Action {}
 
 struct MPDClearQueue: Action {}
 
+struct MPDMoveSongInQueue: Action {
+  let oldQueuePos: Int
+  let newQueuePos: Int
+}
+
 struct MPDAppendTrack: Action {
   let song: MPDClient.MPDSong
 }

Persephone/State/Reducers/MPDReducer.swift

@@ -33,6 +33,9 @@ func mpdReducer(action: Action, state: MPDState?) -> MPDState {
   case is MPDClearQueue:
     App.mpdClient.clearQueue()
 
+  case let action as MPDMoveSongInQueue:
+    App.mpdClient.moveSongInQueue(at: action.oldQueuePos, to: action.newQueuePos)
+
   case let action as MPDAppendTrack:
     App.mpdClient.appendSong(action.song)