feat: added shortcut for split and merge regions

public/config.json

@@ -49,7 +49,9 @@
             "copy": "ctrl+c",
             "cut": "ctrl+x",
             "paste": "ctrl+v",
-            "save": "ctrl+s"
+            "save": "ctrl+s",
+            "split_region": "ctrl+t",
+            "merge_regions": "ctrl+j"
         },
         "piano_roll": {
             "switch": "tab", 

src/components/Toolbar.tsx

@@ -16,14 +16,11 @@ import {
 } from 'react-icons/fa';
 import { KGProject, type KeySignature } from '../core/KGProject';
 import { KGMidiInput } from '../core/midi-input/KGMidiInput';
-import { KGMidiRegion } from '../core/region/KGMidiRegion';
 import { KGAudioTrack } from '../core/track/KGAudioTrack';
 import { plainToInstance } from 'class-transformer';
 import { FaPencil, FaCopy, FaPaste, FaTrash, FaWandMagicSparkles, FaListUl } from 'react-icons/fa6';
 import { KGMainContentState } from '../core/state/KGMainContentState';
 import { regionDeleteManager } from '../util/regionDeleteUtil';
-import { SplitRegionCommand } from '../core/commands/region/SplitRegionCommand';
-import { MergeMidiRegionsCommand } from '../core/commands/region/MergeMidiRegionsCommand';
 import { handleCopyOperation, handlePasteOperation } from '../util/copyPasteUtil';
 import { convertProjectToMidi, convertMidiToProject } from '../util/midiUtil';
 import { KEY_SIGNATURE_MAP } from '../constants/coreConstants';
@@ -35,7 +32,7 @@ import OpenProjectModal from './common/OpenProjectModal';
 import { clearChatHistoryAndUI } from '../util/chatUtil';
 import PianoIcon from './common/icons/PianoIcon';
 import MetronomeIcon from './common/icons/MetronomeIcon';
-import { ConfigManager } from '../core/config/ConfigManager';
+import { mergeSelectedMidiRegions, splitSelectedRegionAtPlayhead } from '../util/regionEditUtil';
 import { showAlert, showChoice, showConfirm, showPrompt, showTimeSigPrompt } from '../util/dialogUtil';
 
 const Toolbar: React.FC = () => {
@@ -791,43 +788,19 @@ const Toolbar: React.FC = () => {
       console.log("Split button clicked");
     }
 
-    if (selectedRegionIds.length === 0) {
-      await showAlert("Please select a region to split.");
-      return;
-    }
-    if (selectedRegionIds.length > 1) {
-      await showAlert("Please select exactly one region to split.");
+    const status = await splitSelectedRegionAtPlayhead({
+      selectedRegionIds,
+      playheadPosition,
+      refreshProjectState,
+    });
+    if (!status) {
       return;
     }
 
-    const regionId = lastSelectedRegionId;
-    const tracks = KGCore.instance().getCurrentProject().getTracks();
-    let targetRegion = null;
-    for (const track of tracks) {
-      const found = track.getRegions().find(r => r.getId() === regionId);
-      if (found) { targetRegion = found; break; }
-    }
-
-    if (!targetRegion) {
-      await showAlert("Selected region not found.");
-      return;
-    }
-
-    const regionStart = targetRegion.getStartFromBeat();
-    const regionEnd = regionStart + targetRegion.getLength();
-
-    if (playheadPosition <= regionStart || playheadPosition >= regionEnd) {
-      await showAlert("The playhead is not inside the selected region. Move the playhead inside the region before splitting.");
-      return;
-    }
-
-    const command = new SplitRegionCommand(regionId, playheadPosition);
-    KGCore.instance().executeCommand(command);
-    refreshProjectState();
-    setStatus(`Split region at beat ${playheadPosition.toFixed(2)}`);
+    setStatus(status);
 
     if (DEBUG_MODE.TOOLBAR) {
-      console.log(`Split region ${regionId} at beat ${playheadPosition}`);
+      console.log(`Split selected region at beat ${playheadPosition}`);
     }
   };
 
@@ -836,92 +809,15 @@ const Toolbar: React.FC = () => {
       console.log('Merge button clicked');
     }
 
-    if (selectedRegionIds.length < 2) {
-      await showAlert('Please select at least two MIDI regions on the same track to merge.');
-      return;
-    }
-
-    const tracks = KGCore.instance().getCurrentProject().getTracks();
-    const selectedRegionIdSet = new Set(selectedRegionIds);
-    const selectedMidiRegions: KGMidiRegion[] = [];
-    let targetTrackId: string | null = null;
-
-    for (const track of tracks) {
-      for (const region of track.getRegions()) {
-        if (!selectedRegionIdSet.has(region.getId())) {
-          continue;
-        }
-
-        if (!(region instanceof KGMidiRegion)) {
-          await showAlert('Only MIDI regions can be merged. Please adjust your selection and try again.');
-          return;
-        }
-
-        const regionTrackId = track.getId().toString();
-        if (targetTrackId && targetTrackId !== regionTrackId) {
-          await showAlert('Please select only MIDI regions from a single track before merging.');
-          return;
-        }
-
-        targetTrackId = regionTrackId;
-        selectedMidiRegions.push(region);
-      }
-    }
-
-    if (selectedMidiRegions.length !== selectedRegionIds.length || !targetTrackId) {
-      await showAlert('Some selected regions could not be found. Please reselect the MIDI regions and try again.');
-      return;
-    }
-
-    const sortedSelectedRegions = [...selectedMidiRegions].sort((a, b) => {
-      const startDelta = a.getStartFromBeat() - b.getStartFromBeat();
-      if (startDelta !== 0) return startDelta;
-      return a.getLength() - b.getLength();
+    const status = await mergeSelectedMidiRegions({
+      selectedRegionIds,
+      refreshProjectState,
     });
-
-    let regionIdsToMerge = selectedRegionIds;
-    const firstSelectedRegion = sortedSelectedRegions[0];
-    const lastSelectedRegion = sortedSelectedRegions[sortedSelectedRegions.length - 1];
-    const spanStart = firstSelectedRegion.getStartFromBeat();
-    const spanEnd = lastSelectedRegion.getStartFromBeat() + lastSelectedRegion.getLength();
-
-    const targetTrack = tracks.find(track => track.getId().toString() === targetTrackId);
-    const inBetweenRegions = targetTrack
-      ?.getRegions()
-      .filter(region => (
-        region instanceof KGMidiRegion &&
-        !selectedRegionIdSet.has(region.getId()) &&
-        region.getStartFromBeat() >= spanStart &&
-        region.getStartFromBeat() <= spanEnd
-      )) ?? [];
-
-    if (inBetweenRegions.length > 0) {
-      const shouldIncludeInBetweenRegions = await showConfirm(
-        'There are additional MIDI regions between the first and last selected regions on this track. Would you like KGStudio to merge those as well?',
-        {
-          confirmLabel: 'Merge All In Between',
-          cancelLabel: 'Stop',
-        }
-      );
-
-      if (!shouldIncludeInBetweenRegions) {
-        return;
-      }
-
-      regionIdsToMerge = Array.from(new Set([
-        ...selectedRegionIds,
-        ...inBetweenRegions.map(region => region.getId()),
-      ]));
+    if (!status) {
+      return;
     }
 
-    try {
-      const command = new MergeMidiRegionsCommand(regionIdsToMerge);
-      KGCore.instance().executeCommand(command, { rethrow: true });
-      refreshProjectState();
-      setStatus(`Merged ${regionIdsToMerge.length} MIDI regions`);
-    } catch (error) {
-      await showAlert(error instanceof Error ? error.message : 'Unable to merge the selected MIDI regions.');
-    }
+    setStatus(status);
   };
 
   // Handle undo button click

src/core/config/ConfigManager.ts

@@ -47,6 +47,7 @@ interface AppConfig {
       hold_to_create_region: string;
       play: string;
       loop: string;
+      record: string;
       undo: string;
       redo: string;
       select_all: string;
@@ -54,6 +55,8 @@ interface AppConfig {
       cut: string;
       paste: string;
       save: string;
+      split_region: string;
+      merge_regions: string;
     };
     piano_roll: {
       switch: string;

src/hooks/useGlobalKeyboardHandler.test.tsx

@@ -0,0 +1,181 @@
+import React from 'react';
+import { fireEvent, render, waitFor } from '@testing-library/react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { useGlobalKeyboardHandler } from './useGlobalKeyboardHandler';
+
+const regionEditUtilMocks = vi.hoisted(() => ({
+  splitSelectedRegionAtPlayhead: vi.fn(),
+  mergeSelectedMidiRegions: vi.fn(),
+}));
+
+const storeState = {
+  undo: vi.fn(),
+  redo: vi.fn(),
+  setStatus: vi.fn(),
+  isPlaying: false,
+  startPlaying: vi.fn(),
+  stopTransport: vi.fn(),
+  toggleLoop: vi.fn(),
+  projectName: 'Test Project',
+  savedProjectName: 'Test Project',
+  setSavedProjectName: vi.fn(),
+  setProjectName: vi.fn(),
+  isRecording: false,
+  startRecording: vi.fn(),
+  stopRecording: vi.fn(),
+  activeRegionId: null,
+  selectedRegionIds: ['region-a', 'region-b'],
+  setActiveRegionId: vi.fn(),
+  setShowPianoRoll: vi.fn(),
+  showPianoRoll: false,
+  openMidiPianoRoll: vi.fn(),
+  openSpectrogramViewer: vi.fn(),
+  playheadPosition: 12,
+  refreshProjectState: vi.fn(),
+};
+
+type StoreState = typeof storeState;
+
+vi.mock('../stores/projectStore', () => ({
+  useProjectStore: (selector?: unknown) => (
+    selector ? (selector as (state: StoreState) => unknown)(storeState) : storeState
+  ),
+}));
+
+vi.mock('../util/osUtil', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('../util/osUtil')>();
+  return {
+    ...actual,
+    matchesKeyboardShortcut: (event: KeyboardEvent, shortcut: string) => {
+      if (shortcut === 'ctrl+t') {
+        return event.ctrlKey && event.key.toLowerCase() === 't';
+      }
+      if (shortcut === 'ctrl+j') {
+        return event.ctrlKey && event.key.toLowerCase() === 'j';
+      }
+      return false;
+    },
+  };
+});
+
+vi.mock('../util/copyPasteUtil', () => ({
+  handleCopyOperation: vi.fn(() => false),
+  handlePasteOperation: vi.fn(() => false),
+}));
+
+vi.mock('../util/saveUtil', () => ({
+  saveProject: vi.fn(),
+}));
+
+vi.mock('../core/config/ConfigManager', () => ({
+  ConfigManager: {
+    instance: () => ({
+      getIsInitialized: () => true,
+      get: (path: string) => {
+        const shortcuts: Record<string, string> = {
+          'hotkeys.main.undo': 'ctrl+z',
+          'hotkeys.main.redo': 'ctrl+shift+z',
+          'hotkeys.main.copy': 'ctrl+c',
+          'hotkeys.main.paste': 'ctrl+v',
+          'hotkeys.main.select_all': 'ctrl+a',
+          'hotkeys.main.play': 'space',
+          'hotkeys.main.loop': 'c',
+          'hotkeys.main.save': 'ctrl+s',
+          'hotkeys.main.record': 'r',
+          'hotkeys.main.split_region': 'ctrl+t',
+          'hotkeys.main.merge_regions': 'ctrl+j',
+        };
+        return shortcuts[path];
+      },
+    }),
+  },
+}));
+
+vi.mock('../util/selectionUtil', () => ({
+  selectAllNotesInActiveRegion: vi.fn(),
+}));
+
+vi.mock('../core/KGCore', () => ({
+  KGCore: {
+    instance: () => ({
+      getCurrentProject: () => ({
+        getTracks: () => [],
+      }),
+    }),
+  },
+}));
+
+vi.mock('../core/midi-input/KGMidiInput', () => ({
+  KGMidiInput: {
+    instance: () => ({
+      getConnectedInputCount: () => 0,
+    }),
+  },
+}));
+
+vi.mock('../core/region/KGMidiRegion', () => ({
+  KGMidiRegion: class {},
+}));
+
+vi.mock('../core/track/KGAudioTrack', () => ({
+  KGAudioTrack: class {},
+}));
+
+vi.mock('../util/regionEditUtil', () => ({
+  splitSelectedRegionAtPlayhead: regionEditUtilMocks.splitSelectedRegionAtPlayhead,
+  mergeSelectedMidiRegions: regionEditUtilMocks.mergeSelectedMidiRegions,
+}));
+
+vi.mock('../util/dialogUtil', () => ({
+  showAlert: vi.fn(),
+}));
+
+const HookHarness = () => {
+  useGlobalKeyboardHandler();
+  return null;
+};
+
+describe('useGlobalKeyboardHandler region shortcuts', () => {
+  beforeEach(() => {
+    regionEditUtilMocks.splitSelectedRegionAtPlayhead.mockReset();
+    regionEditUtilMocks.mergeSelectedMidiRegions.mockReset();
+    storeState.setStatus.mockClear();
+  });
+
+  it('triggers split on Ctrl+T', async () => {
+    regionEditUtilMocks.splitSelectedRegionAtPlayhead.mockResolvedValue('Split region at beat 12.00');
+
+    render(<HookHarness />);
+    fireEvent.keyDown(document.body, { key: 't', ctrlKey: true });
+
+    await waitFor(() => {
+      expect(regionEditUtilMocks.splitSelectedRegionAtPlayhead).toHaveBeenCalledWith({
+        selectedRegionIds: ['region-a', 'region-b'],
+        playheadPosition: 12,
+        refreshProjectState: storeState.refreshProjectState,
+      });
+    });
+
+    await waitFor(() => {
+      expect(storeState.setStatus).toHaveBeenCalledWith('Split region at beat 12.00');
+    });
+  });
+
+  it('triggers merge on Ctrl+J', async () => {
+    regionEditUtilMocks.mergeSelectedMidiRegions.mockResolvedValue('Merged 2 MIDI regions');
+
+    render(<HookHarness />);
+    fireEvent.keyDown(document.body, { key: 'j', ctrlKey: true });
+
+    await waitFor(() => {
+      expect(regionEditUtilMocks.mergeSelectedMidiRegions).toHaveBeenCalledWith({
+        selectedRegionIds: ['region-a', 'region-b'],
+        refreshProjectState: storeState.refreshProjectState,
+      });
+    });
+
+    await waitFor(() => {
+      expect(storeState.setStatus).toHaveBeenCalledWith('Merged 2 MIDI regions');
+    });
+  });
+});

src/hooks/useGlobalKeyboardHandler.ts

@@ -9,6 +9,7 @@ import { KGCore } from '../core/KGCore';
 import { KGMidiInput } from '../core/midi-input/KGMidiInput';
 import { KGMidiRegion } from '../core/region/KGMidiRegion';
 import { KGAudioTrack } from '../core/track/KGAudioTrack';
+import { mergeSelectedMidiRegions, splitSelectedRegionAtPlayhead } from '../util/regionEditUtil';
 import { showAlert } from '../util/dialogUtil';
 
 /**
@@ -16,14 +17,14 @@ import { showAlert } from '../util/dialogUtil';
  * Handles keyboard shortcuts defined in the configuration
  */
 export const useGlobalKeyboardHandler = () => {
-  const { undo, redo, setStatus, isPlaying, startPlaying, stopTransport, toggleLoop, projectName, savedProjectName, setSavedProjectName, setProjectName, isRecording, startRecording, stopRecording, activeRegionId, selectedRegionIds, setActiveRegionId, setShowPianoRoll, showPianoRoll, openMidiPianoRoll, openSpectrogramViewer } = useProjectStore();
+  const { undo, redo, setStatus, isPlaying, startPlaying, stopTransport, toggleLoop, projectName, savedProjectName, setSavedProjectName, setProjectName, isRecording, startRecording, stopRecording, activeRegionId, selectedRegionIds, setActiveRegionId, setShowPianoRoll, showPianoRoll, openMidiPianoRoll, openSpectrogramViewer, playheadPosition, refreshProjectState } = useProjectStore();
   const lastSelectedRegionId = selectedRegionIds[selectedRegionIds.length - 1] ?? null;
 
   useEffect(() => {
     const handleKeyDown = (event: KeyboardEvent) => {
       // Skip if user is typing in an input field
-      const target = event.target as HTMLElement;
-      if (target && (
+      const target = event.target;
+      if (target instanceof HTMLElement && (
         target.tagName === 'INPUT' || 
         target.tagName === 'TEXTAREA' || 
         target.contentEditable === 'true' ||
@@ -71,6 +72,8 @@ export const useGlobalKeyboardHandler = () => {
       const loopShortcut = configManager.get('hotkeys.main.loop') as string;
       const saveShortcut = configManager.get('hotkeys.main.save') as string;
       const recordShortcut = configManager.get('hotkeys.main.record') as string;
+      const splitShortcut = configManager.get('hotkeys.main.split_region') as string;
+      const mergeShortcut = configManager.get('hotkeys.main.merge_regions') as string;
 
       // Check for undo shortcut
       if (undoShortcut && matchesKeyboardShortcut(event, undoShortcut)) {
@@ -202,6 +205,33 @@ export const useGlobalKeyboardHandler = () => {
         return;
       }
 
+      if (splitShortcut && matchesKeyboardShortcut(event, splitShortcut)) {
+        event.preventDefault();
+        void splitSelectedRegionAtPlayhead({
+          selectedRegionIds,
+          playheadPosition,
+          refreshProjectState,
+        }).then(status => {
+          if (status) {
+            setStatus(status);
+          }
+        });
+        return;
+      }
+
+      if (mergeShortcut && matchesKeyboardShortcut(event, mergeShortcut)) {
+        event.preventDefault();
+        void mergeSelectedMidiRegions({
+          selectedRegionIds,
+          refreshProjectState,
+        }).then(status => {
+          if (status) {
+            setStatus(status);
+          }
+        });
+        return;
+      }
+
       // Check for edit/view shortcut (E) — open piano roll for MIDI, spectrogram for audio
       if (event.key.toLowerCase() === 'e' && !event.ctrlKey && !event.metaKey && !event.altKey && !event.shiftKey) {
         event.preventDefault();
@@ -272,11 +302,14 @@ export const useGlobalKeyboardHandler = () => {
     startRecording,
     stopRecording,
     activeRegionId,
+    selectedRegionIds,
     lastSelectedRegionId,
     setActiveRegionId,
     setShowPianoRoll,
     showPianoRoll,
     openMidiPianoRoll,
     openSpectrogramViewer,
+    playheadPosition,
+    refreshProjectState,
   ]); // Include dependencies for store actions
 };

src/util/regionEditUtil.ts

@@ -0,0 +1,158 @@
+import { KGCore } from '../core/KGCore';
+import { SplitRegionCommand } from '../core/commands/region/SplitRegionCommand';
+import { MergeMidiRegionsCommand } from '../core/commands/region/MergeMidiRegionsCommand';
+import { KGMidiRegion } from '../core/region/KGMidiRegion';
+import { showAlert, showConfirm } from './dialogUtil';
+
+interface SplitSelectedRegionParams {
+  selectedRegionIds: string[];
+  playheadPosition: number;
+  refreshProjectState: () => void;
+}
+
+interface MergeSelectedMidiRegionsParams {
+  selectedRegionIds: string[];
+  refreshProjectState: () => void;
+}
+
+export const splitSelectedRegionAtPlayhead = async ({
+  selectedRegionIds,
+  playheadPosition,
+  refreshProjectState,
+}: SplitSelectedRegionParams): Promise<string | null> => {
+  if (selectedRegionIds.length === 0) {
+    await showAlert('Please select a region to split.');
+    return null;
+  }
+
+  if (selectedRegionIds.length > 1) {
+    await showAlert('Please select exactly one region to split.');
+    return null;
+  }
+
+  const regionId = selectedRegionIds[selectedRegionIds.length - 1];
+  const tracks = KGCore.instance().getCurrentProject().getTracks();
+  let targetRegion = null;
+
+  for (const track of tracks) {
+    const foundRegion = track.getRegions().find(region => region.getId() === regionId);
+    if (foundRegion) {
+      targetRegion = foundRegion;
+      break;
+    }
+  }
+
+  if (!targetRegion) {
+    await showAlert('Selected region not found.');
+    return null;
+  }
+
+  const regionStart = targetRegion.getStartFromBeat();
+  const regionEnd = regionStart + targetRegion.getLength();
+
+  if (playheadPosition <= regionStart || playheadPosition >= regionEnd) {
+    await showAlert('The playhead is not inside the selected region. Move the playhead inside the region before splitting.');
+    return null;
+  }
+
+  const command = new SplitRegionCommand(regionId, playheadPosition);
+  KGCore.instance().executeCommand(command);
+  refreshProjectState();
+
+  return `Split region at beat ${playheadPosition.toFixed(2)}`;
+};
+
+export const mergeSelectedMidiRegions = async ({
+  selectedRegionIds,
+  refreshProjectState,
+}: MergeSelectedMidiRegionsParams): Promise<string | null> => {
+  if (selectedRegionIds.length < 2) {
+    await showAlert('Please select at least two MIDI regions on the same track to merge.');
+    return null;
+  }
+
+  const tracks = KGCore.instance().getCurrentProject().getTracks();
+  const selectedRegionIdSet = new Set(selectedRegionIds);
+  const selectedMidiRegions: KGMidiRegion[] = [];
+  let targetTrackId: string | null = null;
+
+  for (const track of tracks) {
+    for (const region of track.getRegions()) {
+      if (!selectedRegionIdSet.has(region.getId())) {
+        continue;
+      }
+
+      if (!(region instanceof KGMidiRegion)) {
+        await showAlert('Only MIDI regions can be merged. Please adjust your selection and try again.');
+        return null;
+      }
+
+      const regionTrackId = track.getId().toString();
+      if (targetTrackId && targetTrackId !== regionTrackId) {
+        await showAlert('Please select only MIDI regions from a single track before merging.');
+        return null;
+      }
+
+      targetTrackId = regionTrackId;
+      selectedMidiRegions.push(region);
+    }
+  }
+
+  if (selectedMidiRegions.length !== selectedRegionIds.length || !targetTrackId) {
+    await showAlert('Some selected regions could not be found. Please reselect the MIDI regions and try again.');
+    return null;
+  }
+
+  const sortedSelectedRegions = [...selectedMidiRegions].sort((a, b) => {
+    const startDelta = a.getStartFromBeat() - b.getStartFromBeat();
+    if (startDelta !== 0) {
+      return startDelta;
+    }
+    return a.getLength() - b.getLength();
+  });
+
+  let regionIdsToMerge = selectedRegionIds;
+  const firstSelectedRegion = sortedSelectedRegions[0];
+  const lastSelectedRegion = sortedSelectedRegions[sortedSelectedRegions.length - 1];
+  const spanStart = firstSelectedRegion.getStartFromBeat();
+  const spanEnd = lastSelectedRegion.getStartFromBeat() + lastSelectedRegion.getLength();
+
+  const targetTrack = tracks.find(track => track.getId().toString() === targetTrackId);
+  const inBetweenRegions = targetTrack
+    ?.getRegions()
+    .filter(region => (
+      region instanceof KGMidiRegion &&
+      !selectedRegionIdSet.has(region.getId()) &&
+      region.getStartFromBeat() >= spanStart &&
+      region.getStartFromBeat() <= spanEnd
+    )) ?? [];
+
+  if (inBetweenRegions.length > 0) {
+    const shouldIncludeInBetweenRegions = await showConfirm(
+      'There are additional MIDI regions between the first and last selected regions on this track. Would you like KGStudio to merge those as well?',
+      {
+        confirmLabel: 'Merge All In Between',
+        cancelLabel: 'Stop',
+      }
+    );
+
+    if (!shouldIncludeInBetweenRegions) {
+      return null;
+    }
+
+    regionIdsToMerge = Array.from(new Set([
+      ...selectedRegionIds,
+      ...inBetweenRegions.map(region => region.getId()),
+    ]));
+  }
+
+  try {
+    const command = new MergeMidiRegionsCommand(regionIdsToMerge);
+    KGCore.instance().executeCommand(command, { rethrow: true });
+    refreshProjectState();
+    return `Merged ${regionIdsToMerge.length} MIDI regions`;
+  } catch (error) {
+    await showAlert(error instanceof Error ? error.message : 'Unable to merge the selected MIDI regions.');
+    return null;
+  }
+};