feat: added logic to get suitable chords (console log only)

src/App.tsx

@@ -12,21 +12,30 @@ import { SettingsPanel } from './components/settings';
 import LoadingOverlay from './components/common/LoadingOverlay';
 import { useEffect as useEffectReact, useState, useRef } from 'react';
 import { KGToneBuffersPool } from './core/audio-interface/KGToneBuffersPool';
-import { KGPianoRollState } from './core/state/KGPianoRollState';
+import { KGCore } from './core/KGCore';
 
 function App() {
   // Enable global keyboard handler for copy/paste and undo/redo
   useGlobalKeyboardHandler();
   
   // Use project store instead of local state for project name and tracks
-  const { 
+  const {
     refreshStatus,
-    loadProject, maxBars, showChatBox, showSettings, setShowSettings, initializeFromConfig,
+    loadProject, showChatBox, showSettings, setShowSettings, initializeFromConfig,
     showInstrumentSelection
   } = useProjectStore();
 
+  // Track if app has been initialized to prevent multiple initializations
+  const hasInitialized = useRef(false);
+
   // Load project when component mounts
   useEffect(() => {
+    // Guard against multiple initializations (can happen due to React Strict Mode or rerenders)
+    if (hasInitialized.current) {
+      return;
+    }
+    hasInitialized.current = true;
+
     const initializeApp = async () => {
       // Load the current project from KGCore
       loadProject(null);
@@ -34,27 +43,39 @@ function App() {
       // Initialize store from config after ConfigManager is ready
       await initializeFromConfig();
 
-      // Load mode list from JSON
+      // Load all mode and chord data files in parallel
       try {
-        const response = await fetch(`${import.meta.env.BASE_URL}resources/modes/mode_list.json`);
+        const [modeListResponse, functionalChordsResponse] = await Promise.all([
-        const data = await response.json();
+          fetch(`${import.meta.env.BASE_URL}resources/modes/mode_list.json`),
+          fetch(`${import.meta.env.BASE_URL}resources/modes/functional_chords.json`)
+        ]);
+
+        const [modeListData, functionalChordsData] = await Promise.all([
+          modeListResponse.json(),
+          functionalChordsResponse.json()
+        ]);
 
         // Store mode data with id, name, and steps
-        KGPianoRollState.MODE_DATA = data.modes;
+        KGCore.MODE_DATA = modeListData.modes;
+        console.log(`Loaded ${modeListData.modes.length} modes:`, modeListData.modes.map((m: { name: string }) => m.name));
 
-        console.log(`Loaded ${data.modes.length} modes:`, data.modes.map((m: { name: string }) => m.name));
+        // Store functional chords data (T/S/D by mode, including mode-specific chord notes)
+        KGCore.FUNCTIONAL_CHORDS_DATA = functionalChordsData;
+        console.log(`Loaded functional chords for ${Object.keys(functionalChordsData).length} modes`);
       } catch (error) {
-        console.error('Failed to load mode list:', error);
+        console.error('Failed to load mode/chord data:', error);
-        // Fallback to default mode
+        // Fallback to defaults
-        KGPianoRollState.MODE_DATA = [{ id: 'ionian', name: 'Ionian', steps: [2, 2, 1, 2, 2, 2, 1] }];
+        KGCore.MODE_DATA = [{ id: 'ionian', name: 'Ionian', steps: [2, 2, 1, 2, 2, 2, 1] }];
+        KGCore.FUNCTIONAL_CHORDS_DATA = {};
       }
 
-      // Log maxBars to console
+      // Log maxBars after initialization completes
-      console.log(`Project max bars: ${maxBars}`);
+      const currentMaxBars = useProjectStore.getState().maxBars;
+      console.log(`Project max bars: ${currentMaxBars}`);
     };
 
     initializeApp();
-  }, [loadProject, maxBars, initializeFromConfig]);
+  }, [loadProject, initializeFromConfig]);
 
   // Refresh status periodically to ensure UI is in sync with KGCore
   useEffect(() => {

src/components/piano-roll/PianoRoll.tsx

@@ -13,6 +13,7 @@ import { KGPianoRollState } from '../../core/state/KGPianoRollState';
 import { ConfigManager } from '../../core/config/ConfigManager';
 import { beatsToBar } from '../../util/midiUtil';
 import { UpdateRegionCommand } from '../../core/commands';
+import { getSuitableChords, noteNameToPitchClass } from '../../util/scaleUtil';
 
 interface PianoRollProps {
   onClose: () => void;
@@ -39,6 +40,9 @@ const PianoRoll: React.FC<PianoRollProps> = ({
   // Snapping state
   const [snapping, setSnapping] = useState<string>('NO SNAP');
 
+  // Chord guide state
+  const [chordGuide, setChordGuide] = useState<string>('N');
+
   // Piano roll state with temporary initial values
   const [position, setPosition] = useState(initialPosition || { x: 0, y: 0 });
   
@@ -303,7 +307,62 @@ const PianoRoll: React.FC<PianoRollProps> = ({
       console.log(`Selected mode: ${value}`);
     }
   }, [setSelectedMode]);
-  
+
+  // Handle chord guide selection
+  const handleChordGuideSelect = useCallback((value: string) => {
+    setChordGuide(value);
+  }, []);
+
+  // Update suitable chords whenever chord guide, key signature, or mode changes
+  useEffect(() => {
+    const pianoRollState = KGPianoRollState.instance();
+
+    if (chordGuide === 'N') {
+      // Disabled - clear chord data
+      pianoRollState.setCurrentSuitableChords({});
+      pianoRollState.setCurrentSuitableChordsPitchClasses({});
+
+      if (DEBUG_MODE.PIANO_ROLL) {
+        console.log(`Chord guide disabled - cleared suitable chords`);
+      }
+    } else {
+      // Get suitable chords for the selected function (T/S/D)
+      const functionType = chordGuide as 'T' | 'S' | 'D';
+      const suitableChords = getSuitableChords(keySignature, selectedMode, functionType);
+
+      // Convert note names to pitch classes (ensuring ascending order)
+      const chordsPitchClasses: Record<string, number[]> = {};
+      for (const [chordSymbol, noteNames] of Object.entries(suitableChords)) {
+        const pitchClasses: number[] = [];
+        let previousPitch = -1;
+
+        for (const noteName of noteNames) {
+          let pitchClass = noteNameToPitchClass(noteName);
+
+          // If this pitch is lower than the previous one, add an octave
+          if (previousPitch >= 0 && pitchClass <= previousPitch) {
+            pitchClass += 12;
+          }
+
+          pitchClasses.push(pitchClass);
+          previousPitch = pitchClass;
+        }
+
+        chordsPitchClasses[chordSymbol] = pitchClasses;
+      }
+
+      // Update piano roll state
+      pianoRollState.setCurrentSuitableChords(suitableChords);
+      pianoRollState.setCurrentSuitableChordsPitchClasses(chordsPitchClasses);
+
+      if (DEBUG_MODE.PIANO_ROLL) {
+        console.log(`Chord guide updated: ${chordGuide} (${functionType})`);
+        console.log(`Suitable chords for ${keySignature} in ${selectedMode} mode:`, suitableChords);
+        console.log(`Pitch classes:`, chordsPitchClasses);
+      }
+    }
+  }, [chordGuide, keySignature, selectedMode]);
+
   // Handler for receiving the setNoteUpdateCounter function from PianoRollContent
   const handleSetNoteUpdateTrigger = (setNoteFn: React.Dispatch<React.SetStateAction<number>>) => {
     triggerNoteUpdateRef.current = setNoteFn;
@@ -775,6 +834,8 @@ const PianoRoll: React.FC<PianoRollProps> = ({
         onSnappingSelect={handleSnappingSelect}
         selectedMode={selectedMode}
         onModeChange={handleModeSelect}
+        chordGuide={chordGuide}
+        onChordGuideChange={handleChordGuideSelect}
         blinkButton={blinkButton}
       />
       

src/components/piano-roll/PianoRollToolbar.tsx

@@ -2,6 +2,7 @@ import React from 'react';
 import { FaMousePointer, FaPencilAlt } from 'react-icons/fa';
 import { KGDropdown } from '../common';
 import { KGPianoRollState } from '../../core/state/KGPianoRollState';
+import { KGCore } from '../../core/KGCore';
 
 interface PianoRollToolbarProps {
   activeTool: 'pointer' | 'pencil';
@@ -13,6 +14,8 @@ interface PianoRollToolbarProps {
   onSnappingSelect: (value: string) => void;
   selectedMode: string;
   onModeChange: (value: string) => void;
+  chordGuide: string;
+  onChordGuideChange: (value: string) => void;
   blinkButton?: string | null;
 }
 
@@ -26,20 +29,35 @@ const PianoRollToolbar: React.FC<PianoRollToolbarProps> = ({
   onSnappingSelect,
   selectedMode,
   onModeChange,
+  chordGuide,
+  onChordGuideChange,
   blinkButton = null
 }) => {
   return (
     <div className="piano-roll-toolbar">
       <div className="toolbar-left">
-        {/* Left section with mode dropdown */}
+        {/* Left section with mode and chord guide dropdowns */}
         <KGDropdown
-          options={KGPianoRollState.MODE_DATA.map(m => ({ label: m.name, value: m.id }))}
+          options={KGCore.MODE_DATA.map(m => ({ label: m.name, value: m.id }))}
           value={selectedMode}
           onChange={(value) => onModeChange(value)}
           label="Mode"
           buttonClassName="mode-dropdown"
           showValueAsLabel={true}
         />
+        <KGDropdown
+          options={[
+            { label: 'Guide: Disabled', value: 'N' },
+            { label: 'Chord Guide: T', value: 'T' },
+            { label: 'Chord Guide: S', value: 'S' }, 
+            { label: 'Chord Guide: D', value: 'D' }
+          ]}
+          value={chordGuide}
+          onChange={(value) => onChordGuideChange(value)}
+          label="Chord"
+          buttonClassName="chord-guide-dropdown"
+          showValueAsLabel={true}
+        />
       </div>
       
       <div className="toolbar-center">

src/core/KGCore.ts

@@ -17,6 +17,10 @@ export class KGCore {
   // Private static instance for singleton pattern
   private static _instance: KGCore | null = null;
 
+  // Global music data resources
+  public static MODE_DATA: Array<{ id: string; name: string; steps: number[] }> = []; // Modes with id, display name, and interval steps
+  public static FUNCTIONAL_CHORDS_DATA: Record<string, { T: string[]; S: string[]; D: string[]; chords: Record<string, string[]> }> = {}; // Functional chords by mode (T/S/D) with mode-specific chord notes
+
   private currentProject: KGProject = new KGProject();
 
   private status: string = "Ready";

src/core/state/KGPianoRollState.ts

@@ -8,13 +8,16 @@ export class KGPianoRollState {
   public static SNAP_OPTIONS: string[] = ['NO SNAP', '1/3', '1/4', '1/6', '1/8', '1/12', '1/16', '1/24', '1/32'];
   public static QUANT_POS_OPTIONS: string[] = ['1/3', '1/4', '1/6', '1/8', '1/12', '1/16', '1/24', '1/32'];
   public static QUANT_LEN_OPTIONS: string[] = ['1/1', '1/2', '1/3', '1/4', '1/6', '1/8', '1/12', '1/16', '1/24', '1/32'];
-  public static MODE_DATA: Array<{ id: string; name: string; steps: number[] }> = []; // Modes with id, display name, and interval steps
 
   private activeTool: string = "pointer";
   private currentSnap: string = "NO SNAP";
   private lastEditedNoteLength: number = 1; // Default to 1 beat
   private currentMode: string = "ionian"; // Default mode
 
+  // Chord guide state
+  private currentSuitableChords: Record<string, string[]> = {}; // Map of chord symbols to note names (e.g., {"I": ["C", "E", "G"]})
+  private currentSuitableChordsPitchClasses: Record<string, number[]> = {}; // Map of chord symbols to pitch classes (e.g., {"I": [0, 4, 7]})
+
   private constructor() {
     console.log("KGPianoRollState initialized");
   }
@@ -58,4 +61,20 @@ export class KGPianoRollState {
   public setCurrentMode(mode: string): void {
     this.currentMode = mode;
   }
+
+  public getCurrentSuitableChords(): Record<string, string[]> {
+    return this.currentSuitableChords;
+  }
+
+  public setCurrentSuitableChords(chords: Record<string, string[]>): void {
+    this.currentSuitableChords = chords;
+  }
+
+  public getCurrentSuitableChordsPitchClasses(): Record<string, number[]> {
+    return this.currentSuitableChordsPitchClasses;
+  }
+
+  public setCurrentSuitableChordsPitchClasses(chordsPitchClasses: Record<string, number[]>): void {
+    this.currentSuitableChordsPitchClasses = chordsPitchClasses;
+  }
 }

src/util/scaleUtil.ts

@@ -1,4 +1,4 @@
-import { KGPianoRollState } from '../core/state/KGPianoRollState';
+import { KGCore } from '../core/KGCore';
 import { pianoRollIndexToPitch } from './midiUtil';
 import type { KeySignature } from '../core/KGProject';
 
@@ -66,7 +66,7 @@ export const getScalePitchClasses = (rootNote: string, modeSteps: number[]): num
  * @returns Array of interval steps, or default ionian if not found
  */
 export const getModeSteps = (modeId: string): number[] => {
-  const modeData = KGPianoRollState.MODE_DATA.find(m => m.id === modeId);
+  const modeData = KGCore.MODE_DATA.find(m => m.id === modeId);
   if (!modeData) {
     console.warn(`Mode not found: ${modeId}, defaulting to ionian`);
     return [2, 2, 1, 2, 2, 2, 1]; // Default to ionian (major scale)
@@ -74,6 +74,137 @@ export const getModeSteps = (modeId: string): number[] => {
   return modeData.steps;
 };
 
+/**
+ * Transposes a note name by a given number of semitones
+ * @param noteName - Note name like "C", "C#", "Db"
+ * @param semitones - Number of semitones to transpose (positive or negative)
+ * @returns Transposed note name
+ */
+const transposeNote = (noteName: string, semitones: number): string => {
+  const noteNames = ['C', 'C#', 'D', 'D#', 'E', 'F', 'F#', 'G', 'G#', 'A', 'A#', 'B'];
+  const pitchClass = noteNameToPitchClass(noteName);
+  const newPitchClass = (pitchClass + semitones + 12) % 12;
+  return noteNames[newPitchClass];
+};
+
+/**
+ * Gets the list of suitable chords for a given key, mode, and functional harmony group
+ * @param keySignature - Key signature like "C major", "F# minor", "Bb major"
+ * @param modeId - Mode ID (e.g., "ionian", "aeolian", "dorian")
+ * @param functionType - Functional harmony group: "T" (Tonic), "S" (Subdominant), or "D" (Dominant)
+ * @returns Map of chord symbols to their transposed note arrays, e.g., { "I": ["C", "E", "G"], "vi": ["A", "C", "E"] }
+ *         Returns empty object if mode or function not found
+ *
+ * Example:
+ * - getSuitableChords("C major", "ionian", "T") returns { "I": ["C", "E", "G"], "vi": ["A", "C", "E"], ... }
+ * - getSuitableChords("D major", "ionian", "T") returns { "I": ["D", "F#", "A"], "vi": ["B", "D", "F#"], ... }
+ */
+export const getSuitableChords = (
+  keySignature: KeySignature,
+  modeId: string,
+  functionType: 'T' | 'S' | 'D'
+): Record<string, string[]> => {
+  // Get the functional chords for this mode
+  const functionalChords = KGCore.FUNCTIONAL_CHORDS_DATA[modeId];
+  if (!functionalChords) {
+    console.warn(`No functional chords found for mode: ${modeId}`);
+    return {};
+  }
+
+  // Get the chord symbols for the specified function (T/S/D)
+  const chordSymbols = functionalChords[functionType];
+  if (!chordSymbols || chordSymbols.length === 0) {
+    console.warn(`No chords found for function ${functionType} in mode ${modeId}`);
+    return {};
+  }
+
+  // Get the mode-specific chords data
+  const modeChords = functionalChords.chords;
+  if (!modeChords) {
+    console.warn(`No chords data found for mode: ${modeId}`);
+    return {};
+  }
+
+  // Get the root note from key signature
+  const rootNote = getRootNoteFromKeySignature(keySignature);
+
+  // Calculate the transposition interval from C to the root note
+  const transposeSemitones = noteNameToPitchClass(rootNote);
+
+  // Build a map of chord symbols to transposed notes
+  const chordMap: Record<string, string[]> = {};
+
+  for (const chordSymbol of chordSymbols) {
+    // Get the chord notes from mode-specific chords data (in C key)
+    const chordNotes = modeChords[chordSymbol];
+    if (!chordNotes) {
+      console.warn(`Chord symbol not found in mode ${modeId} chords: ${chordSymbol}`);
+      continue; // Skip this chord if not found
+    }
+
+    // If the key is C, use notes as-is; otherwise transpose
+    if (rootNote === 'C') {
+      chordMap[chordSymbol] = chordNotes;
+    } else {
+      // Transpose each note in the chord
+      const transposedNotes = chordNotes.map(note => transposeNote(note, transposeSemitones));
+      chordMap[chordSymbol] = transposedNotes;
+    }
+  }
+
+  return chordMap;
+};
+
+/**
+ * Gets the transposed notes for a specific chord in a given key and mode
+ * @param chordSymbol - Chord symbol (e.g., "I", "V7", "ii")
+ * @param keySignature - Key signature like "C major", "F# minor"
+ * @param modeId - Mode ID (e.g., "ionian", "aeolian")
+ * @returns Array of note names for the chord in the specified key, or empty array if not found
+ */
+export const getChordNotesInKey = (
+  chordSymbol: string,
+  keySignature: KeySignature,
+  modeId: string
+): string[] => {
+  // Get the functional chords for this mode
+  const functionalChords = KGCore.FUNCTIONAL_CHORDS_DATA[modeId];
+  if (!functionalChords) {
+    console.warn(`No functional chords found for mode: ${modeId}`);
+    return [];
+  }
+
+  // Get the mode-specific chords data
+  const modeChords = functionalChords.chords;
+  if (!modeChords) {
+    console.warn(`No chords data found for mode: ${modeId}`);
+    return [];
+  }
+
+  // Get the root note from key signature
+  const rootNote = getRootNoteFromKeySignature(keySignature);
+
+  // Get the chord notes from mode-specific chords data (in C key)
+  const chordNotes = modeChords[chordSymbol];
+  if (!chordNotes) {
+    console.warn(`Chord symbol not found in mode ${modeId} chords: ${chordSymbol}`);
+    return [];
+  }
+
+  // If the key is C, return the notes as-is
+  if (rootNote === 'C') {
+    return chordNotes;
+  }
+
+  // Calculate the transposition interval from C to the root note
+  const transposeSemitones = noteNameToPitchClass(rootNote);
+
+  // Transpose each note in the chord
+  const transposedNotes = chordNotes.map(note => transposeNote(note, transposeSemitones));
+
+  return transposedNotes;
+};
+
 /**
  * Generates the CSS background-image string for the piano grid with scale highlighting
  * @param selectedMode - Current mode ID (e.g., "ionian", "dorian")