persephone/Persephone/Controllers/QueueViewController.swift

//
//  QueueController.swift
//  Persephone
//
//  Created by Daniel Barber on 2019/2/01.
//  Copyright © 2019 Dan Barber. All rights reserved.
//

import Cocoa

class QueueViewController: NSViewController,
                           NSOutlineViewDelegate {
  var dataSource = QueueDataSource()

  let systemFontRegular = NSFont.systemFont(ofSize: 13, weight: .regular)
  let systemFontBold = NSFont.systemFont(ofSize: 13, weight: .bold)
  
  let playIcon = NSImage(named: "playButton")
  let pauseIcon = NSImage(named: "pauseButton")

  @IBOutlet var queueView: NSOutlineView!

  override func viewDidLoad() {
    super.viewDidLoad()

    setupNotificationObservers()

    queueView.dataSource = dataSource
    queueView.columnAutoresizingStyle = .sequentialColumnAutoresizingStyle
 }

  override func keyDown(with event: NSEvent) {
    switch event.keyCode {
    case NSEvent.keyCodeSpace:
      nextResponder?.keyDown(with: event)
    default:
      super.keyDown(with: event)
    }
  }

  @IBAction func playTrack(_ sender: Any) {
    if dataSource.queuePos >= 0 {
      AppDelegate.mpdClient.playTrack(queuePos: dataSource.queuePos)
    }
  }

  @objc func stateChanged(_ notification: Notification) {
    guard let state = notification.userInfo?[Notification.stateKey] as? MPDClient.Status.State
      else { return }

    dataSource.setQueueIcon(state)
  }

  @objc func queueChanged(_ notification: Notification) {
    guard let queue = notification.userInfo?[Notification.queueKey] as? [MPDClient.Song]
      else { return }

    dataSource.updateQueue(queue)
    queueView.reloadData()
  }

  @objc func queuePosChanged(_ notification: Notification) {
    guard let queuePos = notification.userInfo?[Notification.queuePosKey] as? Int
      else { return }

    dataSource.setQueuePos(queuePos)

    queueView.reloadData()
  }

  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 songItem = item as? SongItem {
      switch tableColumn?.identifier.rawValue {
      case "songTitleColumn":
        return cellForSongTitle(outlineView, with: songItem)
      case "songArtistColumn":
        return cellForSongArtist(outlineView, with: songItem)
      default:
        return nil
      }
    } else if tableColumn?.identifier.rawValue == "songTitleColumn" {
      return cellForQueueHeading(outlineView)
    } else {
      return nil
    }
  }

  func cellForSongTitle(_ outlineView: NSOutlineView, with songItem: SongItem) -> NSView {
    let cellView = outlineView.makeView(
      withIdentifier: .queueSongTitle,
      owner: self
      ) as! NSTableCellView

    cellView.textField?.stringValue = songItem.song.getTag(.title)
    if songItem.isPlaying {
      cellView.textField?.font = systemFontBold
      cellView.imageView?.image = dataSource.queueIcon
    } else {
      cellView.textField?.font = systemFontRegular
      cellView.imageView?.image = nil
    }

    return cellView
  }

  func cellForSongArtist(_ outlineView: NSOutlineView, with songItem: SongItem) -> NSView {
    let cellView = outlineView.makeView(
      withIdentifier: .queueSongArtist,
      owner: self
      ) as! NSTableCellView

    cellView.textField?.stringValue = songItem.song.getTag(.artist)
    if songItem.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
  }

  func setupNotificationObservers() {
    NotificationCenter.default.addObserver(
      self,
      selector: #selector(stateChanged(_:)),
      name: Notification.stateChanged,
      object: AppDelegate.mpdClient
    )

    NotificationCenter.default.addObserver(
      self,
      selector: #selector(queueChanged(_:)),
      name: Notification.queueChanged,
      object: AppDelegate.mpdClient
    )

    NotificationCenter.default.addObserver(
      self,
      selector: #selector(queuePosChanged(_:)),
      name: Notification.queuePosChanged,
      object: AppDelegate.mpdClient
    )
  }
}