Add a way to prevent auto playback

resolves #62

src/spessasynth_lib/sequencer/sequencer.js

@@ -26,14 +26,16 @@ import { DUMMY_MIDI_DATA, MidiData } from "../midi_parser/midi_data.js";
 
 /**
  * @typedef {Object} SequencerOptions
- * @property {boolean} skipToFirstNoteOn - if true, the sequencer will skip to the first note
+ * @property {boolean|undefined} skipToFirstNoteOn - if true, the sequencer will skip to the first note
+ * @property {boolean|undefined} autoPlay - if true, the sequencer will automatically start playing the MIDI
  */
 
 /**
  * @type {SequencerOptions}
  */
 const DEFAULT_OPTIONS = {
-    skipToFirstNoteOn: true
+    skipToFirstNoteOn: true,
+    autoPlay: true
 };
 
 export class Sequencer
@@ -117,6 +119,13 @@ export class Sequencer
          */
         this.isFinished = false;
 
+        /**
+         * Indicates if the sequencer is paused.
+         * Paused if a number, undefined if playing
+         * @type {undefined|number}
+         */
+        this.pausedTime = undefined;
+
         /**
          * The current sequence's length, in seconds
          * @type {number}
@@ -137,7 +146,7 @@ export class Sequencer
             this._sendMessage(WorkletSequencerMessageType.setSkipToFirstNote, false);
         }
 
-        this.loadNewSongList(midiBinaries);
+        this.loadNewSongList(midiBinaries, options?.autoPlay ?? false);
 
         window.addEventListener("beforeunload", this.resetMIDIOut.bind(this));
     }
@@ -167,7 +176,7 @@ export class Sequencer
     get currentTime()
     {
         // return the paused time if it's set to something other than undefined
-        if (this.pausedTime)
+        if (this.pausedTime !== undefined)
         {
             return this.pausedTime;
         }
@@ -198,7 +207,7 @@ export class Sequencer
      */
     get currentHighResolutionTime()
     {
-        if (this.pausedTime)
+        if (this.pausedTime !== undefined)
         {
             return this.pausedTime;
         }
@@ -364,7 +373,11 @@ export class Sequencer
                 this.absoluteStartTime = 0;
                 this.duration = this.midiData.duration;
                 Object.entries(this.onSongChange).forEach((callback) => callback[1](songChangeData));
-                this.unpause();
+                // if is auto played, unpause
+                if (messageData[2] === true)
+                {
+                    this.unpause();
+                }
                 break;
 
             case WorkletSequencerReturnMessageType.textEvent:
@@ -437,22 +450,28 @@ export class Sequencer
     }
 
     /**
-     * @param midiBuffers {MIDIFile[]}
+     * Loads a new song list
+     * @param midiBuffers {MIDIFile[]} - the MIDI files to play
+     * @param autoPlay {boolean} - if true, the first sequence will automatically start playing
      */
-    loadNewSongList(midiBuffers)
+    loadNewSongList(midiBuffers, autoPlay = true)
     {
         this.pause();
         // add some dummy data
         this.midiData = DUMMY_MIDI_DATA;
         this.hasDummyData = true;
         this.duration = 99999;
-        this._sendMessage(WorkletSequencerMessageType.loadNewSongList, midiBuffers);
+        this._sendMessage(WorkletSequencerMessageType.loadNewSongList, [midiBuffers, autoPlay]);
         this.songIndex = 0;
         this.songsAmount = midiBuffers.length;
         if (this.songsAmount > 1)
         {
             this.loop = false;
         }
+        if (autoPlay === false)
+        {
+            this.pausedTime = this.currentTime;
+        }
     }
 
     /**

src/spessasynth_lib/sequencer/worklet_sequencer/events.js

@@ -16,7 +16,7 @@ export function processMessage(messageType, messageData)
             break;
 
         case WorkletSequencerMessageType.loadNewSongList:
-            this.loadNewSongList(messageData);
+            this.loadNewSongList(messageData[0], messageData[1]);
             break;
 
         case WorkletSequencerMessageType.pause:

src/spessasynth_lib/sequencer/worklet_sequencer/sequencer_message.js

@@ -32,10 +32,10 @@ export const WorkletSequencerMessageType = {
  */
 export const WorkletSequencerReturnMessageType = {
     midiEvent: 0,               // [...midiEventBytes<number>]
-    songChange: 1,              // [midiData<MidiData>, songIndex<number>]
+    songChange: 1,              // [midiData<MidiData>, songIndex<number>, isAutoPlayed<boolean>]
     textEvent: 2,               // [messageData<number[]>, statusByte<number]
     timeChange: 3,              // newAbsoluteTime<number>
     pause: 4,                   // no data
     getMIDI: 5,                 // midiData<MIDI>
-    midiError: 6               // errorMSG<string>
+    midiError: 6                // errorMSG<string>
 };

src/spessasynth_lib/sequencer/worklet_sequencer/song_control.js

@@ -41,9 +41,10 @@ export function assignMIDIPort(trackNum, port)
 /**
  * Loads a new sequence
  * @param parsedMidi {BasicMIDI}
+ * @param autoPlay {boolean}
  * @this {WorkletSequencer}
  */
-export function loadNewSequence(parsedMidi)
+export function loadNewSequence(parsedMidi, autoPlay = true)
 {
     this.stop();
     if (!parsedMidi.tracks)
@@ -122,9 +123,8 @@ export function loadNewSequence(parsedMidi)
     this.firstNoteTime = MIDIticksToSeconds(this.midiData.firstNoteOn, this.midiData);
     SpessaSynthInfo(`%cTotal song time: ${formatTime(Math.ceil(this.duration)).time}`, consoleColors.recognized);
 
-    this.post(WorkletSequencerReturnMessageType.songChange, [new MidiData(this.midiData), this.songIndex]);
+    this.post(WorkletSequencerReturnMessageType.songChange, [new MidiData(this.midiData), this.songIndex, autoPlay]);
 
-    this.synth.resetAllControllers();
     if (this.duration <= 1)
     {
         SpessaSynthWarn(
@@ -133,14 +133,25 @@ export function loadNewSequence(parsedMidi)
         );
         this.loop = false;
     }
-    this.play(true);
+    if (autoPlay)
+    {
+        this.play(true);
+    }
+    else
+    {
+        // this shall not play: play to the first note and then wait
+        const targetTime = this._skipToFirstNoteOn ? this.midiData.firstNoteOn - 1 : 0;
+        this.setTimeTicks(targetTime);
+        this.pause();
+    }
 }
 
 /**
  * @param midiBuffers {MIDIFile[]}
+ * @param autoPlay {boolean}
  * @this {WorkletSequencer}
  */
-export function loadNewSongList(midiBuffers)
+export function loadNewSongList(midiBuffers, autoPlay = true)
 {
     /**
      * parse the MIDIs (only the array buffers, MIDI is unchanged)
@@ -173,7 +184,7 @@ export function loadNewSongList(midiBuffers)
     {
         this.loop = false;
     }
-    this.loadNewSequence(this.songs[this.songIndex]);
+    this.loadNewSequence(this.songs[this.songIndex], autoPlay);
 }
 
 /**

src/spessasynth_lib/sequencer/worklet_sequencer/worklet_sequencer.js

@@ -119,7 +119,7 @@ class WorkletSequencer
     get currentTime()
     {
         // return the paused time if it's set to something other than undefined
-        if (this.pausedTime)
+        if (this.pausedTime !== undefined)
         {
             return this.pausedTime;
         }

src/website/js/manager/manager.js

@@ -440,6 +440,7 @@ class Manager
         if (this.seq)
         {
             this.seq.loadNewSongList(parsedMidi);
+            this.seq.play(true);
             return;
         }
 
@@ -464,7 +465,7 @@ class Manager
         this.settingsUI.addSequencer(this.seq);
 
         // play the midi
-        this.seq.play(true);
+        //this.seq.play(true);
     }
 
     downloadDesfont()