bugfixing

src/app/modules/songs/services/text-rendering.service.ts

@@ -1,5 +1,6 @@
 import {Injectable} from '@angular/core';
-import {TransposeMode, TransposeService} from './transpose.service';
+import {TransposeService} from './transpose.service';
+import {TransposeMode} from './transpose-mode';
 
 export enum SectionType {
   Verse,

src/app/modules/songs/services/transpose-mode.ts

@@ -0,0 +1,4 @@
+export interface TransposeMode {
+  baseKey: string;
+  targetKey: string
+}

src/app/modules/songs/services/transpose.service.ts

@@ -2,11 +2,6 @@ import {Injectable} from '@angular/core';
 import {Chord, Line, LineType} from './text-rendering.service';
 import {getScaleType, scaleMapping} from './key.helper';
 
-export interface TransposeMode {
-  baseKey: string;
-  targetKey: string
-}
-
 @Injectable({
   providedIn: 'root'
 })
@@ -17,7 +12,7 @@ export class TransposeService {
     const difference = this.getDistance(baseKey, targetKey);
     const map = this.getMap(baseKey, difference);
 
-    const chords = line.chords.map(chord => this.transposeChord(chord, map));
+    const chords = difference > 0 ? line.chords.map(chord => this.transposeChord(chord, map)) : line.chords;
     const renderedLine = this.renderLine(chords);
 
     return {...line, text: renderedLine, chords};
@@ -32,14 +27,15 @@ export class TransposeService {
 
   public getDistance(baseKey: string, targetKey: string): number {
     const scale = getScaleType(baseKey);
-    return (
+    return scale ? (
       (scale[0].indexOf(targetKey) - scale[0].indexOf(baseKey)) ??
       (scale[1].indexOf(targetKey) - scale[1].indexOf(baseKey))
-    ) % 12;
+    ) % 12 : 0;
   }
 
   public getMap(baseKey: string, difference: number) {
     const scale = getScaleType(baseKey);
+    if (!scale) return null;
     const map = {};
     for (let i = 0; i < 12; i++) {
       const source = scale[0][i];

src/app/widget-modules/components/song-text/song-text.component.ts

@@ -8,7 +8,7 @@ import {
 } from '../../../modules/songs/services/text-rendering.service';
 import {faGripLines} from '@fortawesome/free-solid-svg-icons/faGripLines';
 import {songSwitch} from './animation';
-import {TransposeMode} from '../../../modules/songs/services/transpose.service';
+import {TransposeMode} from '../../../modules/songs/services/transpose-mode';
 
 export type ChordMode = 'show' | 'hide' | 'onlyFirst'