FIX: sửa lỗi vị trí con trỏ pos khi parse MIDI MThd header

app/static/js/app.jsx

@@ -14863,7 +14863,7 @@ const App = () => {
 
     var header = String.fromCharCode(data[0], data[1], data[2], data[3]);
     if (header !== 'MThd') return null;
-    read32(); var fmt = read16(); var numTracks = read16(); var division = read16();
+    pos = 8; var fmt = read16(); var numTracks = read16(); var division = read16();
     var ticksPerBeat = (division & 0x8000) ? 480 : (division || 480);
     var bpm = 120;
     var result = [];

app/static/js/app.precompiled.js

@@ -408,7 +408,7 @@ const handleHandleDragStart=(e,side)=>{e.preventDefault();e.stopPropagation();co
 const toggleTrackSoloEvaluate=trackId=>{const wasPlaying=isPlaying;stopAllPlayback();setTracks(prev=>prev.map(t=>{if(t.id===trackId){return{...t,solo:!t.solo,muted:false};}return{...t,solo:false};}));if(wasPlaying){setTimeout(()=>{startOffsetTimeRef.current=currentTime;startAudioTimeRef.current=getAudioContext().currentTime;setIsPlaying(true);},50);}setTimeout(()=>lucide.createIcons(),50);};const toggleTrackMute=trackId=>{const beforeSnap=captureTrackSnapshot(trackId);setTracks(prev=>prev.map(t=>t.id===trackId?{...t,muted:!t.muted}:t));setUndoStack(prev=>{const next=[...prev,{action_type:'MUTE',track_id:trackId,timestamp:Date.now(),before_state:beforeSnap,after_state:captureTrackSnapshot(trackId)}];if(next.length>MAX_UNDO)next.shift();return next;});setTimeout(()=>lucide.createIcons(),50);};const updateTrackProp=(trackId,props)=>{setTracks(prev=>prev.map(t=>t.id===trackId?{...t,...props}:t));setTimeout(()=>lucide.createIcons(),50);};const toggleTrackDrum=trackId=>{var mt=tracks||[];var tidx=mt.findIndex(function(tr){return tr.id===trackId;});if(tidx<0)tidx=0;setTracks(prev=>prev.map(t=>{if(t.id!==trackId)return t;const becomingPercussion=!t.is_percussion;let newBank=becomingPercussion?128:t._saved_sf_bank!==undefined?t._saved_sf_bank:0;let newProgram=becomingPercussion?0:t._saved_sf_program!==undefined?t._saved_sf_program:0;let newCh=becomingPercussion?9:t._saved_sf_channel!==undefined?t._saved_sf_channel:tidx%16;return{...t,is_percussion:becomingPercussion,soundfont_bank:newBank,instrumentProgram:newProgram,midiChannel:newCh,_saved_sf_bank:becomingPercussion?t.soundfont_bank:t._saved_sf_bank,_saved_sf_program:becomingPercussion?t.instrumentProgram:t._saved_sf_program,_saved_sf_channel:becomingPercussion?t.midiChannel:t._saved_sf_channel,synth_engine:t.synth_engine?{...t.synth_engine,soundfont_bank:newBank,soundfont_program:newProgram}:t.synth_engine};}));setTimeout(()=>lucide.createIcons(),50);};const updateTrackVolumeDb=(trackId,val)=>{const beforeSnap=captureTrackSnapshot(trackId);setTracks(prev=>prev.map(t=>t.id===trackId?{...t,volumeDb:val}:t));setUndoStack(prev=>{const next=[...prev,{action_type:'VOLUME_CHANGE',track_id:trackId,timestamp:Date.now(),before_state:beforeSnap,after_state:captureTrackSnapshot(trackId)}];if(next.length>MAX_UNDO)next.shift();return next;});// Real-time update during playback
 const nodes=activeTrackNodesRef.current[trackId];if(nodes){const volLinear=val<=-50?0:Math.pow(10,val/20);nodes.gainNode.gain.setValueAtTime(volLinear,getAudioContext().currentTime);}};const updateTrackPan=(trackId,val)=>{const beforeSnap=captureTrackSnapshot(trackId);setTracks(prev=>prev.map(t=>t.id===trackId?{...t,pan:val}:t));setUndoStack(prev=>{const next=[...prev,{action_type:'PAN_CHANGE',track_id:trackId,timestamp:Date.now(),before_state:beforeSnap,after_state:captureTrackSnapshot(trackId)}];if(next.length>MAX_UNDO)next.shift();return next;});// Real-time update during playback
 const nodes=activeTrackNodesRef.current[trackId];if(nodes){nodes.pannerNode.pan.setValueAtTime(val/100,getAudioContext().currentTime);}};const updateTrackName=(trackId,name)=>{const beforeSnap=captureTrackSnapshot(trackId);setTracks(prev=>prev.map(t=>t.id===trackId?{...t,name}:t));setUndoStack(prev=>{const next=[...prev,{action_type:'RENAME',track_id:trackId,timestamp:Date.now(),before_state:beforeSnap,after_state:captureTrackSnapshot(trackId)}];if(next.length>MAX_UNDO)next.shift();return next;});};const updateTrackColor=(trackId,color)=>{const beforeSnap=captureTrackSnapshot(trackId);setTracks(prev=>prev.map(t=>t.id===trackId?{...t,color}:t));setUndoStack(prev=>{const next=[...prev,{action_type:'RECOLOR',track_id:trackId,timestamp:Date.now(),before_state:beforeSnap,after_state:captureTrackSnapshot(trackId)}];if(next.length>MAX_UNDO)next.shift();return next;});};const updateClipName=(trackId,clipId,newName)=>{setTracks(prev=>prev.map(t=>{if(t.id!==trackId)return t;const clips=t.clips&&t.clips.length>0?t.clips:[];return{...t,clips:clips.map(c=>c.id===clipId?{...c,name:newName}:c)};}));};// ── MIDI .mid file parser ──
-const parseMidiFile=arrayBuffer=>{const data=new Uint8Array(arrayBuffer);if(data.length<14)return null;var pos=0;var read32=function(){var v=data[pos]<<24|data[pos+1]<<16|data[pos+2]<<8|data[pos+3];pos+=4;return v;};var read16=function(){var v=data[pos]<<8|data[pos+1];pos+=2;return v;};var readVLQ=function(){var v=0,b;do{b=data[pos++];v=v<<7|b&0x7f;}while(b&0x80);return v;};var header=String.fromCharCode(data[0],data[1],data[2],data[3]);if(header!=='MThd')return null;read32();var fmt=read16();var numTracks=read16();var division=read16();var ticksPerBeat=division&0x8000?480:division||480;var bpm=120;var result=[];for(var t=0;t<numTracks;t++){if(pos+8>data.length)break;var trkId=String.fromCharCode(data[pos],data[pos+1],data[pos+2],data[pos+3]);pos+=4;var trkLen=read32();var endPos=Math.min(pos+trkLen,data.length);if(trkId!=='MTrk'){pos=endPos;continue;}var absTicks=0;var runningStatus=0;var trackName='MIDI Track '+(t+1);var midiNotes=[];var pendingNotes={};var maxAbsTick=0;while(pos<endPos){try{var delta=readVLQ();absTicks+=delta;var status=data[pos];if(status>=0x80){if(status<0xf0){runningStatus=status;}pos++;}else{status=runningStatus;}var cmd=status>>4;if(cmd===0x9||cmd===0x8){var chan=status&0x0F;var pitch=data[pos++];var vel=pos<endPos?data[pos++]:0;var noteKey=chan+'_'+pitch;if(cmd===0x9&&vel>0){pendingNotes[noteKey]={tick:absTicks,vel:vel};if(absTicks>maxAbsTick)maxAbsTick=absTicks;}else{var pn=pendingNotes[noteKey];if(pn){var durTicks=absTicks-pn.tick;if(durTicks<=0)durTicks=240;midiNotes.push({id:'mn_'+t+'_'+pitch+'_'+pn.tick,pitch:pitch,start_beat:pn.tick/ticksPerBeat,duration_beats:durTicks/ticksPerBeat,velocity:Math.min(1,pn.vel/127)});delete pendingNotes[noteKey];}}}else if(status>=0xc0&&status<0xe0){if(pos<endPos)pos+=1;}else if(status>=0xe0&&status<0xf0){if(pos+2<=endPos)pos+=2;}else if(status>=0xa0&&status<0xc0){if(pos+2<=endPos)pos+=2;}else if(status>=0xf0&&status<0xf8){if(pos<endPos){var sl=readVLQ();pos+=sl;}}else if(status===0xff){if(pos>=endPos)break;var metaType=data[pos++];var metaLen=readVLQ();if(metaType===0x03){try{trackName=String.fromCharCode.apply(null,Array.from(data.subarray(pos,pos+metaLen)));}catch(e){}}else if(metaType===0x51&&pos+3<=endPos){bpm=Math.round(60000000/(data[pos]<<16|data[pos+1]<<8|data[pos+2]));}pos+=Math.min(metaLen,endPos-pos);}else{if(pos+2<=endPos)pos+=2;}}catch(e){pos=endPos;}}Object.keys(pendingNotes).forEach(function(k){var pn=pendingNotes[k];var parts=k.split('_');var p=parseInt(parts[1]);var dur=Math.max(240,maxAbsTick-pn.tick);midiNotes.push({id:'mn_'+t+'_'+p+'_'+pn.tick,pitch:p,start_beat:pn.tick/ticksPerBeat,duration_beats:dur/ticksPerBeat,velocity:Math.min(1,pn.vel/127)});});if(midiNotes.length>0){var lastEnd=0;midiNotes.forEach(function(n){var e=(n.start_beat+n.duration_beats)*60/bpm;if(e>lastEnd)lastEnd=e;});result.push({name:trackName,notes:midiNotes,duration:lastEnd||4,startTime:0,id:'midi_'+t+'_'+Date.now()});}pos=endPos;}return result.length>0?result:null;};// ── Load File on Track (with server upload) ──
+const parseMidiFile=arrayBuffer=>{const data=new Uint8Array(arrayBuffer);if(data.length<14)return null;var pos=0;var read32=function(){var v=data[pos]<<24|data[pos+1]<<16|data[pos+2]<<8|data[pos+3];pos+=4;return v;};var read16=function(){var v=data[pos]<<8|data[pos+1];pos+=2;return v;};var readVLQ=function(){var v=0,b;do{b=data[pos++];v=v<<7|b&0x7f;}while(b&0x80);return v;};var header=String.fromCharCode(data[0],data[1],data[2],data[3]);if(header!=='MThd')return null;pos=8;var fmt=read16();var numTracks=read16();var division=read16();var ticksPerBeat=division&0x8000?480:division||480;var bpm=120;var result=[];for(var t=0;t<numTracks;t++){if(pos+8>data.length)break;var trkId=String.fromCharCode(data[pos],data[pos+1],data[pos+2],data[pos+3]);pos+=4;var trkLen=read32();var endPos=Math.min(pos+trkLen,data.length);if(trkId!=='MTrk'){pos=endPos;continue;}var absTicks=0;var runningStatus=0;var trackName='MIDI Track '+(t+1);var midiNotes=[];var pendingNotes={};var maxAbsTick=0;while(pos<endPos){try{var delta=readVLQ();absTicks+=delta;var status=data[pos];if(status>=0x80){if(status<0xf0){runningStatus=status;}pos++;}else{status=runningStatus;}var cmd=status>>4;if(cmd===0x9||cmd===0x8){var chan=status&0x0F;var pitch=data[pos++];var vel=pos<endPos?data[pos++]:0;var noteKey=chan+'_'+pitch;if(cmd===0x9&&vel>0){pendingNotes[noteKey]={tick:absTicks,vel:vel};if(absTicks>maxAbsTick)maxAbsTick=absTicks;}else{var pn=pendingNotes[noteKey];if(pn){var durTicks=absTicks-pn.tick;if(durTicks<=0)durTicks=240;midiNotes.push({id:'mn_'+t+'_'+pitch+'_'+pn.tick,pitch:pitch,start_beat:pn.tick/ticksPerBeat,duration_beats:durTicks/ticksPerBeat,velocity:Math.min(1,pn.vel/127)});delete pendingNotes[noteKey];}}}else if(status>=0xc0&&status<0xe0){if(pos<endPos)pos+=1;}else if(status>=0xe0&&status<0xf0){if(pos+2<=endPos)pos+=2;}else if(status>=0xa0&&status<0xc0){if(pos+2<=endPos)pos+=2;}else if(status>=0xf0&&status<0xf8){if(pos<endPos){var sl=readVLQ();pos+=sl;}}else if(status===0xff){if(pos>=endPos)break;var metaType=data[pos++];var metaLen=readVLQ();if(metaType===0x03){try{trackName=String.fromCharCode.apply(null,Array.from(data.subarray(pos,pos+metaLen)));}catch(e){}}else if(metaType===0x51&&pos+3<=endPos){bpm=Math.round(60000000/(data[pos]<<16|data[pos+1]<<8|data[pos+2]));}pos+=Math.min(metaLen,endPos-pos);}else{if(pos+2<=endPos)pos+=2;}}catch(e){pos=endPos;}}Object.keys(pendingNotes).forEach(function(k){var pn=pendingNotes[k];var parts=k.split('_');var p=parseInt(parts[1]);var dur=Math.max(240,maxAbsTick-pn.tick);midiNotes.push({id:'mn_'+t+'_'+p+'_'+pn.tick,pitch:p,start_beat:pn.tick/ticksPerBeat,duration_beats:dur/ticksPerBeat,velocity:Math.min(1,pn.vel/127)});});if(midiNotes.length>0){var lastEnd=0;midiNotes.forEach(function(n){var e=(n.start_beat+n.duration_beats)*60/bpm;if(e>lastEnd)lastEnd=e;});result.push({name:trackName,notes:midiNotes,duration:lastEnd||4,startTime:0,id:'midi_'+t+'_'+Date.now()});}pos=endPos;}return result.length>0?result:null;};// ── Load File on Track (with server upload) ──
 const loadFileOnTrack=async(trackId,file)=>{if(!file)return;var fileName=file.name||'';var isMidi=/\.mid$|\.midi$/i.test(fileName);showToast(`Đang nạp file ${fileName}...`,'info');try{if(isMidi){var arrayBuffer=await file.arrayBuffer();var midiResult=parseMidiFile(arrayBuffer);if(!midiResult||midiResult.length===0){showToast('Không tìm thấy nốt nhạc trong file MIDI.','error');return;}if(midiResult.length===1){updateActiveTracks(prev=>prev.map(function(t){if(t.id!==trackId)return t;return{...t,name:fileName,midiItems:[midiResult[0]]};}));showToast('Đã tải MIDI: '+fileName,'success');}else{var colors=['#0f766e','#1d4ed8','#701a75','#a21caf','#b45309','#ca8a04','#dc2626','#0891b2'];var firstDone=false;midiResult.forEach(function(midiItem,idx){if(!firstDone){updateActiveTracks(prev=>prev.map(function(t){if(t.id!==trackId)return t;return{...t,name:midiItem.name||fileName,midiItems:[midiItem]};}));firstDone=true;}else{var newId='midi_track_'+Date.now()+'_'+idx;updateActiveTracks(function(prev){var curLen=prev.length;return prev.concat([{id:newId,name:midiItem.name||'MIDI Track '+(idx+1),buffer:null,startTime:0,volumeDb:0,pan:0,muted:false,solo:false,color:colors[idx%colors.length],markers:[],serverFileId:null,clips:[],sections:[],midiItems:[midiItem],isArmed:false,monitoringEnabled:true,inputSource:{deviceType:'NONE',deviceId:''}}]);});}});showToast('Đã tải MIDI: '+midiResult.length+' tracks from '+fileName,'success');}return;}// Upload to server
 uploadToServer(file,trackId);// Decode locally for playback + analyze channels (stereo/mono)
 const{audioBuffer:decodedBuffer,channelInfo}=await window.SonicAudio.decodeAudioFile(file);setTracks(prev=>prev.map(t=>t.id===trackId?{...t,name:fileName,buffer:decodedBuffer,channelInfo:channelInfo}:t));showToast(`Nạp file thành công: ${fileName} (${channelInfo.label})`,'success');}catch(err){showToast(isMidi?"Lỗi giải mã MIDI.":"Lỗi giải mã âm thanh. Định dạng file không tương thích.",'error');}};// ── Synth Generators ──