From 0452ec55b2a231f6e6ea1a6131eff95f45af8a63 Mon Sep 17 00:00:00 2001
From: benjamin <smuddyx@gmail.com>
Date: Wed, 11 Mar 2026 17:13:17 +0100
Subject: [PATCH] validate chords #3

---
 .../services/text-rendering.service.spec.ts   | 761 +++++++++---------
 .../songs/services/text-rendering.service.ts  | 209 +++--
 .../songs/song-list/song-list.component.html  |   7 +-
 .../songs/song-list/song-list.component.less  |   9 +
 .../songs/song-list/song-list.component.ts    |  18 +-
 .../edit/edit-song/edit-song.component.html   |   2 +-
 .../edit/edit-song/edit-song.component.less   |   5 +
 .../modules/songs/song/song.component.html    |  13 +-
 .../song-text/song-text.component.html        |   4 +-
 .../song-text/song-text.component.less        |   9 +
 .../song-text/song-text.component.ts          |  49 +-
 11 files changed, 624 insertions(+), 462 deletions(-)

diff --git a/src/app/modules/songs/services/text-rendering.service.spec.ts b/src/app/modules/songs/services/text-rendering.service.spec.ts
index 405d0ac..973e838 100644
--- a/src/app/modules/songs/services/text-rendering.service.spec.ts
+++ b/src/app/modules/songs/services/text-rendering.service.spec.ts
@@ -17,6 +17,7 @@ describe('TextRenderingService', () => {
       modifiers: [],
       ...partial,
     });
+
   const testText = `Strophe
 C D E F G A H
 Text Line 1-1
@@ -44,412 +45,454 @@ Cool bridge without any chords
     void expect(service).toBeTruthy();
   });
 
-  it('should parse section types', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const sections = service.parse(testText, null);
-    void expect(sections[0].type).toBe(SectionType.Verse);
-    void expect(sections[0].number).toBe(0);
-    void expect(sections[1].type).toBe(SectionType.Verse);
-    void expect(sections[1].number).toBe(1);
-    void expect(sections[2].type).toBe(SectionType.Chorus);
-    void expect(sections[2].number).toBe(0);
-    void expect(sections[3].type).toBe(SectionType.Bridge);
-    void expect(sections[3].number).toBe(0);
-  });
+  describe('section parsing', () => {
+    it('should parse section types', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const sections = service.parse(testText, null);
+      void expect(sections[0].type).toBe(SectionType.Verse);
+      void expect(sections[0].number).toBe(0);
+      void expect(sections[1].type).toBe(SectionType.Verse);
+      void expect(sections[1].number).toBe(1);
+      void expect(sections[2].type).toBe(SectionType.Chorus);
+      void expect(sections[2].number).toBe(0);
+      void expect(sections[3].type).toBe(SectionType.Bridge);
+      void expect(sections[3].number).toBe(0);
+    });
 
-  it('should parse text lines', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const sections = service.parse(testText, null);
-    void expect(sections[0].lines[1].type).toBe(LineType.text);
-    void expect(sections[0].lines[1].text).toBe('Text Line 1-1');
-    void expect(sections[0].lines[3].type).toBe(LineType.text);
-    void expect(sections[0].lines[3].text).toBe('Text Line 2-1');
-    void expect(sections[1].lines[1].type).toBe(LineType.text);
-    void expect(sections[1].lines[1].text).toBe('Text Line 1-2');
-    void expect(sections[1].lines[3].type).toBe(LineType.text);
-    void expect(sections[1].lines[3].text).toBe('Text Line 2-2');
-    void expect(sections[2].lines[1].type).toBe(LineType.text);
-    void expect(sections[2].lines[1].text).toBe('and the chorus');
-    void expect(sections[3].lines[0].type).toBe(LineType.text);
-    void expect(sections[3].lines[0].text).toBe('Cool bridge without any chords');
-  });
-
-  it('should parse chord lines', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const sections = service.parse(testText, null);
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[0].lines[0].text).toBe('C D E F G A H');
-    void expect(sections[0].lines[2].type).toBe(LineType.chord);
-    void expect(sections[0].lines[2].text).toBe(' a d e f g a h c b');
-    void expect(sections[1].lines[0].type).toBe(LineType.chord);
-    void expect(sections[1].lines[0].text).toBe('C D E F G A H');
-    void expect(sections[1].lines[2].type).toBe(LineType.chord);
-    void expect(sections[1].lines[2].text).toBe(' a d e f g a h c b');
-    void expect(sections[2].lines[0].type).toBe(LineType.chord);
-    void expect(sections[2].lines[0].text).toBe('c c♯ d♭ c7   cmaj7    c/e');
-
-    // c c# db c7   cmaj7    c/e
-    void expect(sections[2].lines[0].chords).toEqual([
-      {chord: 'c', length: 1, position: 0, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'c#', length: 2, position: 2, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'db', length: 2, position: 5, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'c', length: 2, position: 8, add: '7', slashChord: null, addDescriptor: descriptor('7', {extensions: ['7']})},
-      {chord: 'c', length: 5, position: 13, add: 'maj7', slashChord: null, addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
-      {chord: 'c', length: 3, position: 22, add: null, slashChord: 'e', addDescriptor: null},
-    ]);
-  });
-
-  it('should parse chords with a lot of symbols', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-g#       F#         E          g#       F#          E
-text`;
-    const sections = service.parse(text, null);
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[0].lines[0].text).toBe('g♯       F♯         E          g♯       F♯          E');
-    void expect(sections[0].lines[1].type).toBe(LineType.text);
-    void expect(sections[0].lines[1].text).toBe('text');
-  });
-
-  it('should ignore indented comment lines when comments are disabled', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-  # hidden comment
-Text`;
-
-    const sections = service.parse(text, null, false);
-
-    void expect(sections[0].lines.length).toBe(1);
-    void expect(sections[0].lines[0].text).toBe('Text');
-  });
-
-  it('should accept section headers with numbering and lowercase letters', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `strophe 1
+    it('should accept section headers with numbering and lowercase letters', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `strophe 1
 Text A
 Refrain 2
 Text B`;
 
-    const sections = service.parse(text, null);
+      const sections = service.parse(text, null);
 
-    void expect(sections.length).toBe(2);
-    void expect(sections[0].type).toBe(SectionType.Verse);
-    void expect(sections[1].type).toBe(SectionType.Chorus);
-  });
+      void expect(sections.length).toBe(2);
+      void expect(sections[0].type).toBe(SectionType.Verse);
+      void expect(sections[1].type).toBe(SectionType.Chorus);
+    });
 
-  it('should return an empty array for empty input', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
+    it('should return an empty array for empty input', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
 
-    void expect(service.parse('', null)).toEqual([]);
-  });
+      void expect(service.parse('', null)).toEqual([]);
+    });
 
-  it('should ignore content before the first recognized section header', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Intro ohne Section
+    it('should ignore content before the first recognized section header', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Intro ohne Section
 Noch eine Zeile
 Strophe
 Text`;
 
-    const sections = service.parse(text, null);
+      const sections = service.parse(text, null);
 
-    void expect(sections.length).toBe(1);
-    void expect(sections[0].lines.length).toBe(1);
-    void expect(sections[0].lines[0].text).toBe('Text');
+      void expect(sections.length).toBe(1);
+      void expect(sections[0].lines.length).toBe(1);
+      void expect(sections[0].lines[0].text).toBe('Text');
+    });
+
+    it('should support windows line endings', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = 'Strophe\r\nC D E\r\nText\r\nRefrain\r\nG A H';
+
+      const sections = service.parse(text, null);
+
+      void expect(sections.length).toBe(2);
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[1].lines[0].type).toBe(LineType.chord);
+    });
   });
 
-  it('should keep comment lines when comments are enabled', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
+  describe('comments and text lines', () => {
+    it('should parse text lines', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const sections = service.parse(testText, null);
+      void expect(sections[0].lines[1].type).toBe(LineType.text);
+      void expect(sections[0].lines[1].text).toBe('Text Line 1-1');
+      void expect(sections[0].lines[3].type).toBe(LineType.text);
+      void expect(sections[0].lines[3].text).toBe('Text Line 2-1');
+      void expect(sections[1].lines[1].type).toBe(LineType.text);
+      void expect(sections[1].lines[1].text).toBe('Text Line 1-2');
+      void expect(sections[1].lines[3].type).toBe(LineType.text);
+      void expect(sections[1].lines[3].text).toBe('Text Line 2-2');
+      void expect(sections[2].lines[1].type).toBe(LineType.text);
+      void expect(sections[2].lines[1].text).toBe('and the chorus');
+      void expect(sections[3].lines[0].type).toBe(LineType.text);
+      void expect(sections[3].lines[0].text).toBe('Cool bridge without any chords');
+    });
+
+    it('should ignore indented comment lines when comments are disabled', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+  # hidden comment
+Text`;
+
+      const sections = service.parse(text, null, false);
+
+      void expect(sections[0].lines.length).toBe(1);
+      void expect(sections[0].lines[0].text).toBe('Text');
+    });
+
+    it('should keep comment lines when comments are enabled', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
 # Kommentar
 Text`;
 
-    const sections = service.parse(text, null, true);
+      const sections = service.parse(text, null, true);
 
-    void expect(sections[0].lines.length).toBe(2);
-    void expect(sections[0].lines[0].text).toBe('# Kommentar');
-    void expect(sections[0].lines[1].text).toBe('Text');
-  });
+      void expect(sections[0].lines.length).toBe(2);
+      void expect(sections[0].lines[0].text).toBe('# Kommentar');
+      void expect(sections[0].lines[1].text).toBe('Text');
+    });
 
-  it('should support windows line endings', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = 'Strophe\r\nC D E\r\nText\r\nRefrain\r\nG A H';
-
-    const sections = service.parse(text, null);
-
-    void expect(sections.length).toBe(2);
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[1].lines[0].type).toBe(LineType.chord);
-  });
-
-  it('should not classify ordinary text with isolated note letters as a chord line', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
+    it('should not classify ordinary text with isolated note letters as a chord line', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
 Anna geht heute baden
 Text`;
 
-    const sections = service.parse(text, null);
+      const sections = service.parse(text, null);
 
-    void expect(sections[0].lines[0].type).toBe(LineType.text);
-    void expect(sections[0].lines[0].chords).toBeNull();
-  });
+      void expect(sections[0].lines[0].type).toBe(LineType.text);
+      void expect(sections[0].lines[0].chords).toBeNull();
+    });
 
-  it('should preserve exact chord positions for spaced chord lines', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-C       G/B      Am
-Text`;
-
-    const sections = service.parse(text, null);
-
-    void expect(sections[0].lines[0].chords).toEqual([
-      {chord: 'C', length: 1, position: 0, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'G', length: 3, position: 8, add: null, slashChord: 'B', addDescriptor: null},
-      {chord: 'A', length: 2, position: 17, add: 'm', slashChord: null, addDescriptor: descriptor('m', {quality: 'minor'})},
-    ]);
-  });
-
-  it('should parse common international chord suffixes and slash chords after the suffix', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-Cmaj7 Dm7 Gsus4 Aadd9 Cmaj7/E
-Text`;
-
-    const sections = service.parse(text, null);
-
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[0].lines[0].chords).toEqual([
-      {chord: 'C', length: 5, position: 0, add: 'maj7', slashChord: null, addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
-      {chord: 'D', length: 3, position: 6, add: 'm7', slashChord: null, addDescriptor: descriptor('m7', {quality: 'minor', extensions: ['7']})},
-      {chord: 'G', length: 5, position: 10, add: 'sus4', slashChord: null, addDescriptor: descriptor('sus4', {suspensions: ['4']})},
-      {chord: 'A', length: 5, position: 16, add: 'add9', slashChord: null, addDescriptor: descriptor('add9', {additions: ['9']})},
-      {chord: 'C', length: 7, position: 22, add: 'maj7', slashChord: 'E', addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
-    ]);
-  });
-
-  it('should parse german chord suffixes', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-Hmoll Edur Cverm Faug
-Text`;
-
-    const sections = service.parse(text, null);
-
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[0].lines[0].chords).toEqual([
-      {chord: 'H', length: 5, position: 0, add: 'moll', slashChord: null, addDescriptor: descriptor('moll', {quality: 'minor'})},
-      {chord: 'E', length: 4, position: 6, add: 'dur', slashChord: null, addDescriptor: descriptor('dur', {quality: 'major'})},
-      {chord: 'C', length: 5, position: 11, add: 'verm', slashChord: null, addDescriptor: descriptor('verm', {quality: 'diminished'})},
-      {chord: 'F', length: 4, position: 17, add: 'aug', slashChord: null, addDescriptor: descriptor('aug', {quality: 'augmented'})},
-    ]);
-  });
-
-  it('should parse numeric and altered chord suffixes', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-C7 D9 E11 F13 Gadd#9 A7-5
-Text`;
-
-    const sections = service.parse(text, null);
-
-    void expect(sections[0].lines[0].chords).toEqual([
-      {chord: 'C', length: 2, position: 0, add: '7', slashChord: null, addDescriptor: descriptor('7', {extensions: ['7']})},
-      {chord: 'D', length: 2, position: 3, add: '9', slashChord: null, addDescriptor: descriptor('9', {extensions: ['9']})},
-      {chord: 'E', length: 3, position: 6, add: '11', slashChord: null, addDescriptor: descriptor('11', {extensions: ['11']})},
-      {chord: 'F', length: 3, position: 10, add: '13', slashChord: null, addDescriptor: descriptor('13', {extensions: ['13']})},
-      {chord: 'G', length: 6, position: 14, add: 'add#9', slashChord: null, addDescriptor: descriptor('add#9', {additions: ['#9']})},
-      {chord: 'A', length: 4, position: 21, add: '7-5', slashChord: null, addDescriptor: descriptor('7-5', {extensions: ['7'], alterations: ['-5']})},
-    ]);
-  });
-
-  it('should parse lowercase roots with suffixes and slash chords', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-emoll d/F# cmaj7/e
-Text`;
-
-    const sections = service.parse(text, null);
-
-    void expect(sections[0].lines[0].chords).toEqual([
-      {chord: 'e', length: 5, position: 0, add: 'moll', slashChord: null, addDescriptor: descriptor('moll', {quality: 'minor'})},
-      {chord: 'd', length: 4, position: 6, add: null, slashChord: 'F#', addDescriptor: null},
-      {chord: 'c', length: 7, position: 11, add: 'maj7', slashChord: 'e', addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
-    ]);
-  });
-
-  it('should keep parentheses around alternative chord groups', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-C F G e C  (F G)
-Text`;
-
-    const sections = service.parse(text, null);
-
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[0].lines[0].text).toBe('C F G e C  (F G)');
-    void expect(sections[0].lines[0].chords).toEqual([
-      {chord: 'C', length: 1, position: 0, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'F', length: 1, position: 2, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'G', length: 1, position: 4, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'e', length: 1, position: 6, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'C', length: 1, position: 8, add: null, slashChord: null, addDescriptor: null},
-      {chord: 'F', length: 2, position: 11, add: null, slashChord: null, addDescriptor: null, prefix: '('},
-      {chord: 'G', length: 2, position: 14, add: null, slashChord: null, addDescriptor: null, suffix: ')'},
-    ]);
-  });
-
-  it('should transpose multiple chords inside a parenthesized group', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-C F G e C  (F G)
-Text`;
-
-    const sections = service.parse(text, {baseKey: 'C', targetKey: 'D'});
-
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[0].lines[0].text).toBe('D G A f♯ D  (G A)');
-  });
-
-  it('should treat compact prose-like tokens as text when the chord ratio is too low', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
+    it('should treat compact prose-like tokens as text when the chord ratio is too low', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
 Das ist C nicht D sondern Text
 Text`;
 
-    const sections = service.parse(text, null);
+      const sections = service.parse(text, null);
 
-    void expect(sections[0].lines[0].type).toBe(LineType.text);
-    void expect(sections[0].lines[0].chords).toBeNull();
-  });
+      void expect(sections[0].lines[0].type).toBe(LineType.text);
+      void expect(sections[0].lines[0].chords).toBeNull();
+    });
 
-  it('should call the transpose service when a transpose mode is provided', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const transposeService = TestBed.inject(TransposeService);
-    const transposeSpy = spyOn(transposeService, 'transpose').and.callThrough();
-    const renderSpy = spyOn(transposeService, 'renderChords').and.callThrough();
-    const text = `Strophe
-C D E
-Text`;
-
-    service.parse(text, {baseKey: 'C', targetKey: 'D'});
-
-    void expect(transposeSpy).toHaveBeenCalledTimes(2);
-    void expect(renderSpy).not.toHaveBeenCalled();
-  });
-
-  it('should use renderChords when no transpose mode is provided', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const transposeService = TestBed.inject(TransposeService);
-    const transposeSpy = spyOn(transposeService, 'transpose').and.callThrough();
-    const renderSpy = spyOn(transposeService, 'renderChords').and.callThrough();
-    const text = `Strophe
-C D E
-Text`;
-
-    service.parse(text, null);
-
-    void expect(renderSpy).toHaveBeenCalledTimes(2);
-    void expect(transposeSpy).not.toHaveBeenCalled();
-  });
-
-  it('should expose semantic descriptors for complex chord additions', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-Cmaj7(add9) Dm7 Gsus4 A7-5
-Text`;
-
-    const sections = service.parse(text, null);
-    const chords = sections[0].lines[0].chords ?? [];
-
-    void expect(chords[0].addDescriptor).toEqual(
-      descriptor('maj7(add9)', {
-        quality: 'major',
-        extensions: ['7'],
-        modifiers: ['(add9)'],
-      })
-    );
-    void expect(chords[1].addDescriptor).toEqual(descriptor('m7', {quality: 'minor', extensions: ['7']}));
-    void expect(chords[2].addDescriptor).toEqual(descriptor('sus4', {suspensions: ['4']}));
-    void expect(chords[3].addDescriptor).toEqual(descriptor('7-5', {extensions: ['7'], alterations: ['-5']}));
-  });
-
-  it('should report non-canonical sharp and flat aliases on chord lines', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-Fis Hmoll Des/Fis
-Text`;
-
-    void expect(service.validateChordNotation(text)).toEqual([
-      jasmine.objectContaining({lineNumber: 2, token: 'Fis', suggestion: 'F#', reason: 'alias'}),
-      jasmine.objectContaining({lineNumber: 2, token: 'Hmoll', suggestion: 'h', reason: 'minor_format'}),
-      jasmine.objectContaining({lineNumber: 2, token: 'Des/Fis', suggestion: 'Db/F#', reason: 'alias'}),
-    ]);
-  });
-
-  it('should report uppercase minor and lowercase major chord notation', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
-Am Dm7 cdur C
-Text`;
-
-    void expect(service.validateChordNotation(text)).toEqual([
-      jasmine.objectContaining({lineNumber: 2, token: 'Am', suggestion: 'a', reason: 'minor_format'}),
-      jasmine.objectContaining({lineNumber: 2, token: 'Dm7', suggestion: 'd7', reason: 'minor_format'}),
-      jasmine.objectContaining({lineNumber: 2, token: 'cdur', suggestion: 'C', reason: 'major_format'}),
-    ]);
-  });
-
-  it('should ignore prose lines even if they contain note-like words', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
+    it('should ignore prose lines even if they contain note-like words', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
 Heute singt Fis nicht mit
 Text`;
 
-    void expect(service.validateChordNotation(text)).toEqual([]);
+      void expect(service.validateChordNotation(text)).toEqual([]);
+    });
   });
 
-  it('should keep mostly-chord lines with unknown tokens in chord mode', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
+  describe('chord parsing', () => {
+    it('should parse chord lines', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const sections = service.parse(testText, null);
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[0].lines[0].text).toBe('C D E F G A H');
+      void expect(sections[0].lines[2].type).toBe(LineType.chord);
+      void expect(sections[0].lines[2].text).toBe(' a d e f g a h c b');
+      void expect(sections[1].lines[0].type).toBe(LineType.chord);
+      void expect(sections[1].lines[0].text).toBe('C D E F G A H');
+      void expect(sections[1].lines[2].type).toBe(LineType.chord);
+      void expect(sections[1].lines[2].text).toBe(' a d e f g a h c b');
+      void expect(sections[2].lines[0].type).toBe(LineType.chord);
+      void expect(sections[2].lines[0].text).toBe('c c♯ d♭ c7   cmaj7    c/e');
+
+      void expect(sections[2].lines[0].chords).toEqual([
+        {chord: 'c', length: 1, position: 0, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'c#', length: 2, position: 2, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'db', length: 2, position: 5, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'c', length: 2, position: 8, add: '7', slashChord: null, addDescriptor: descriptor('7', {extensions: ['7']})},
+        {chord: 'c', length: 5, position: 13, add: 'maj7', slashChord: null, addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
+        {chord: 'c', length: 3, position: 22, add: null, slashChord: 'e', addDescriptor: null},
+      ]);
+    });
+
+    it('should parse chords with a lot of symbols', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+g#       F#         E          g#       F#          E
+text`;
+      const sections = service.parse(text, null);
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[0].lines[0].text).toBe('g♯       F♯         E          g♯       F♯          E');
+      void expect(sections[0].lines[1].type).toBe(LineType.text);
+      void expect(sections[0].lines[1].text).toBe('text');
+    });
+
+    it('should preserve exact chord positions for spaced chord lines', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+C       G/B      Am
+Text`;
+
+      const sections = service.parse(text, null);
+
+      void expect(sections[0].lines[0].chords).toEqual([
+        {chord: 'C', length: 1, position: 0, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'G', length: 3, position: 8, add: null, slashChord: 'B', addDescriptor: null},
+        {chord: 'A', length: 2, position: 17, add: 'm', slashChord: null, addDescriptor: descriptor('m', {quality: 'minor'})},
+      ]);
+    });
+
+    it('should parse common international chord suffixes and slash chords after the suffix', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+Cmaj7 Dm7 Gsus4 Aadd9 Cmaj7/E
+Text`;
+
+      const sections = service.parse(text, null);
+
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[0].lines[0].chords).toEqual([
+        {chord: 'C', length: 5, position: 0, add: 'maj7', slashChord: null, addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
+        {chord: 'D', length: 3, position: 6, add: 'm7', slashChord: null, addDescriptor: descriptor('m7', {quality: 'minor', extensions: ['7']})},
+        {chord: 'G', length: 5, position: 10, add: 'sus4', slashChord: null, addDescriptor: descriptor('sus4', {suspensions: ['4']})},
+        {chord: 'A', length: 5, position: 16, add: 'add9', slashChord: null, addDescriptor: descriptor('add9', {additions: ['9']})},
+        {chord: 'C', length: 7, position: 22, add: 'maj7', slashChord: 'E', addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
+      ]);
+    });
+
+    it('should parse german chord suffixes', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+Hmoll Edur Cverm Faug
+Text`;
+
+      const sections = service.parse(text, null);
+
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[0].lines[0].chords).toEqual([
+        {chord: 'H', length: 5, position: 0, add: 'moll', slashChord: null, addDescriptor: descriptor('moll', {quality: 'minor'})},
+        {chord: 'E', length: 4, position: 6, add: 'dur', slashChord: null, addDescriptor: descriptor('dur', {quality: 'major'})},
+        {chord: 'C', length: 5, position: 11, add: 'verm', slashChord: null, addDescriptor: descriptor('verm', {quality: 'diminished'})},
+        {chord: 'F', length: 4, position: 17, add: 'aug', slashChord: null, addDescriptor: descriptor('aug', {quality: 'augmented'})},
+      ]);
+    });
+
+    it('should parse numeric and altered chord suffixes', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+C7 D9 E11 F13 Gadd#9 A7-5
+Text`;
+
+      const sections = service.parse(text, null);
+
+      void expect(sections[0].lines[0].chords).toEqual([
+        {chord: 'C', length: 2, position: 0, add: '7', slashChord: null, addDescriptor: descriptor('7', {extensions: ['7']})},
+        {chord: 'D', length: 2, position: 3, add: '9', slashChord: null, addDescriptor: descriptor('9', {extensions: ['9']})},
+        {chord: 'E', length: 3, position: 6, add: '11', slashChord: null, addDescriptor: descriptor('11', {extensions: ['11']})},
+        {chord: 'F', length: 3, position: 10, add: '13', slashChord: null, addDescriptor: descriptor('13', {extensions: ['13']})},
+        {chord: 'G', length: 6, position: 14, add: 'add#9', slashChord: null, addDescriptor: descriptor('add#9', {additions: ['#9']})},
+        {chord: 'A', length: 4, position: 21, add: '7-5', slashChord: null, addDescriptor: descriptor('7-5', {extensions: ['7'], alterations: ['-5']})},
+      ]);
+    });
+
+    it('should parse lowercase roots with suffixes and slash chords', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+emoll d/F# cmaj7/e
+Text`;
+
+      const sections = service.parse(text, null);
+
+      void expect(sections[0].lines[0].chords).toEqual([
+        {chord: 'e', length: 5, position: 0, add: 'moll', slashChord: null, addDescriptor: descriptor('moll', {quality: 'minor'})},
+        {chord: 'd', length: 4, position: 6, add: null, slashChord: 'F#', addDescriptor: null},
+        {chord: 'c', length: 7, position: 11, add: 'maj7', slashChord: 'e', addDescriptor: descriptor('maj7', {quality: 'major', extensions: ['7']})},
+      ]);
+    });
+
+    it('should expose semantic descriptors for complex chord additions', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+Cmaj7(add9) Dm7 Gsus4 A7-5
+Text`;
+
+      const sections = service.parse(text, null);
+      const chords = sections[0].lines[0].chords ?? [];
+
+      void expect(chords[0].addDescriptor).toEqual(
+        descriptor('maj7(add9)', {
+          quality: 'major',
+          extensions: ['7'],
+          modifiers: ['(add9)'],
+        })
+      );
+      void expect(chords[1].addDescriptor).toEqual(descriptor('m7', {quality: 'minor', extensions: ['7']}));
+      void expect(chords[2].addDescriptor).toEqual(descriptor('sus4', {suspensions: ['4']}));
+      void expect(chords[3].addDescriptor).toEqual(descriptor('7-5', {extensions: ['7'], alterations: ['-5']}));
+    });
+
+    it('should not misinterpret modifier parentheses as group wrappers', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+Cmaj7(add9)
+Text`;
+
+      const sections = service.parse(text, null);
+
+      void expect(sections[0].lines[0].text).toBe('Cmaj7(add9)');
+      void expect(sections[0].lines[0].chords).toEqual([
+        {chord: 'C', length: 11, position: 0, add: 'maj7(add9)', slashChord: null, addDescriptor: descriptor('maj7(add9)', {
+          quality: 'major',
+          extensions: ['7'],
+          modifiers: ['(add9)'],
+        })},
+      ]);
+      void expect(service.validateChordNotation(text)).toEqual([]);
+    });
+  });
+
+  describe('parenthesized groups', () => {
+    it('should keep parentheses around alternative chord groups', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+C F G e C  (F G)
+Text`;
+
+      const sections = service.parse(text, null);
+
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[0].lines[0].text).toBe('C F G e C  (F G)');
+      void expect(sections[0].lines[0].chords).toEqual([
+        {chord: 'C', length: 1, position: 0, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'F', length: 1, position: 2, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'G', length: 1, position: 4, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'e', length: 1, position: 6, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'C', length: 1, position: 8, add: null, slashChord: null, addDescriptor: null},
+        {chord: 'F', length: 2, position: 11, add: null, slashChord: null, addDescriptor: null, prefix: '('},
+        {chord: 'G', length: 2, position: 14, add: null, slashChord: null, addDescriptor: null, suffix: ')'},
+      ]);
+    });
+
+    it('should transpose multiple chords inside a parenthesized group', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+C F G e C  (F G)
+Text`;
+
+      const sections = service.parse(text, {baseKey: 'C', targetKey: 'D'});
+
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[0].lines[0].text).toBe('D G A f♯ D  (G A)');
+    });
+  });
+
+  describe('transpose integration', () => {
+    it('should call the transpose service when a transpose mode is provided', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const transposeService = TestBed.inject(TransposeService);
+      const transposeSpy = spyOn(transposeService, 'transpose').and.callThrough();
+      const renderSpy = spyOn(transposeService, 'renderChords').and.callThrough();
+      const text = `Strophe
+C D E
+Text`;
+
+      service.parse(text, {baseKey: 'C', targetKey: 'D'});
+
+      void expect(transposeSpy).toHaveBeenCalledTimes(2);
+      void expect(renderSpy).not.toHaveBeenCalled();
+    });
+
+    it('should use renderChords when no transpose mode is provided', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const transposeService = TestBed.inject(TransposeService);
+      const transposeSpy = spyOn(transposeService, 'transpose').and.callThrough();
+      const renderSpy = spyOn(transposeService, 'renderChords').and.callThrough();
+      const text = `Strophe
+C D E
+Text`;
+
+      service.parse(text, null);
+
+      void expect(renderSpy).toHaveBeenCalledTimes(2);
+      void expect(transposeSpy).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('notation validation', () => {
+    it('should report non-canonical sharp and flat aliases on chord lines', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+Fis Hmoll Des/Fis
+Text`;
+
+      void expect(service.validateChordNotation(text)).toEqual([
+        jasmine.objectContaining({lineNumber: 2, token: 'Fis', suggestion: 'F#', reason: 'alias'}),
+        jasmine.objectContaining({lineNumber: 2, token: 'Hmoll', suggestion: 'h', reason: 'minor_format'}),
+        jasmine.objectContaining({lineNumber: 2, token: 'Des/Fis', suggestion: 'Db/F#', reason: 'alias'}),
+      ]);
+    });
+
+    it('should report uppercase minor and lowercase major chord notation', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+Am Dm7 cdur C
+Text`;
+
+      void expect(service.validateChordNotation(text)).toEqual([
+        jasmine.objectContaining({lineNumber: 2, token: 'Am', suggestion: 'a', reason: 'minor_format'}),
+        jasmine.objectContaining({lineNumber: 2, token: 'Dm7', suggestion: 'd7', reason: 'minor_format'}),
+        jasmine.objectContaining({lineNumber: 2, token: 'cdur', suggestion: 'C', reason: 'major_format'}),
+      ]);
+    });
+
+    it('should keep slash bass notes uppercase in canonical minor suggestions', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
+Am/C# Dm7/F#
+Text`;
+
+      void expect(service.validateChordNotation(text)).toEqual([
+        jasmine.objectContaining({lineNumber: 2, token: 'Am/C#', suggestion: 'a/C#', reason: 'minor_format'}),
+        jasmine.objectContaining({lineNumber: 2, token: 'Dm7/F#', suggestion: 'd7/F#', reason: 'minor_format'}),
+      ]);
+    });
+
+    it('should keep mostly-chord lines with unknown tokens in chord mode', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
 C Es G
 Text`;
 
-    const sections = service.parse(text, null);
+      const sections = service.parse(text, null);
 
-    void expect(sections[0].lines[0].type).toBe(LineType.chord);
-    void expect(sections[0].lines[0].text).toBe('C Es G');
-    void expect(service.validateChordNotation(text)).toEqual([
-      jasmine.objectContaining({lineNumber: 2, token: 'Es', reason: 'alias', suggestion: 'Eb'}),
-    ]);
-  });
+      void expect(sections[0].lines[0].type).toBe(LineType.chord);
+      void expect(sections[0].lines[0].text).toBe('C Es G');
+      void expect(service.validateChordNotation(text)).toEqual([
+        jasmine.objectContaining({lineNumber: 2, token: 'Es', reason: 'alias', suggestion: 'Eb'}),
+      ]);
+    });
 
-  it('should flag unknown tokens on mostly chord lines', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = `Strophe
+    it('should flag unknown tokens on mostly chord lines', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = `Strophe
 C Foo G a
 Text`;
 
-    void expect(service.validateChordNotation(text)).toEqual([
-      jasmine.objectContaining({lineNumber: 2, token: 'Foo', reason: 'unknown_token', suggestion: null}),
-    ]);
-  });
+      void expect(service.validateChordNotation(text)).toEqual([
+        jasmine.objectContaining({lineNumber: 2, token: 'Foo', reason: 'unknown_token', suggestion: null}),
+      ]);
+    });
 
-  it('should reject tabs on chord lines', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = 'Strophe\nC\tG\ta\nText';
+    it('should reject tabs on chord lines', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = 'Strophe\nC\tG\ta\nText';
 
-    void expect(service.validateChordNotation(text)).toContain(
-      jasmine.objectContaining({
-        lineNumber: 2,
-        token: '\t',
-        reason: 'tab_character',
-      })
-    );
-  });
+      void expect(service.validateChordNotation(text)).toContain(
+        jasmine.objectContaining({
+          lineNumber: 2,
+          token: '\t',
+          reason: 'tab_character',
+        })
+      );
+    });
 
-  it('should not flag tabs on non chord lines', () => {
-    const service: TextRenderingService = TestBed.inject(TextRenderingService);
-    const text = 'Strophe\nDas\tist normaler Text\nText';
+    it('should not flag tabs on non chord lines', () => {
+      const service: TextRenderingService = TestBed.inject(TextRenderingService);
+      const text = 'Strophe\nDas\tist normaler Text\nText';
 
-    void expect(service.validateChordNotation(text)).toEqual([]);
+      void expect(service.validateChordNotation(text)).toEqual([]);
+    });
   });
 });
diff --git a/src/app/modules/songs/services/text-rendering.service.ts b/src/app/modules/songs/services/text-rendering.service.ts
index 432c3fd..b37bafb 100644
--- a/src/app/modules/songs/services/text-rendering.service.ts
+++ b/src/app/modules/songs/services/text-rendering.service.ts
@@ -7,6 +7,48 @@ import {LineType} from './line-type';
 import {Chord, ChordAddDescriptor, ChordValidationIssue} from './chord';
 import {Line} from './line';
 
+const CHORD_ROOT_DEFINITIONS = [
+  {canonical: 'C#', aliases: ['Cis']},
+  {canonical: 'Db', aliases: ['Des']},
+  {canonical: 'D#', aliases: ['Dis']},
+  {canonical: 'Eb', aliases: ['Es']},
+  {canonical: 'F#', aliases: ['Fis']},
+  {canonical: 'Gb', aliases: ['Ges']},
+  {canonical: 'G#', aliases: ['Gis']},
+  {canonical: 'Ab', aliases: ['As']},
+  {canonical: 'A#', aliases: ['Ais']},
+  {canonical: 'C', aliases: []},
+  {canonical: 'D', aliases: []},
+  {canonical: 'E', aliases: []},
+  {canonical: 'F', aliases: []},
+  {canonical: 'G', aliases: []},
+  {canonical: 'A', aliases: []},
+  {canonical: 'B', aliases: ['Hb']},
+  {canonical: 'H', aliases: []},
+  {canonical: 'c#', aliases: ['cis']},
+  {canonical: 'db', aliases: ['des']},
+  {canonical: 'd#', aliases: ['dis']},
+  {canonical: 'eb', aliases: ['es']},
+  {canonical: 'f#', aliases: ['fis']},
+  {canonical: 'gb', aliases: ['ges']},
+  {canonical: 'g#', aliases: ['gis']},
+  {canonical: 'ab', aliases: ['as']},
+  {canonical: 'a#', aliases: ['ais']},
+  {canonical: 'c', aliases: []},
+  {canonical: 'd', aliases: []},
+  {canonical: 'e', aliases: []},
+  {canonical: 'f', aliases: []},
+  {canonical: 'g', aliases: []},
+  {canonical: 'a', aliases: []},
+  {canonical: 'b', aliases: ['hb']},
+  {canonical: 'h', aliases: []},
+] as const;
+
+const CANONICAL_CHORD_ROOTS = CHORD_ROOT_DEFINITIONS.map(entry => entry.canonical);
+const ALTERNATIVE_CHORD_ROOTS = Object.fromEntries(
+  CHORD_ROOT_DEFINITIONS.flatMap(entry => entry.aliases.map(alias => [alias, entry.canonical]))
+) as Record<string, string>;
+
 interface ParsedValidationToken {
   prefix: string;
   root: string;
@@ -18,7 +60,9 @@ interface ParsedValidationToken {
 }
 
 interface ChordLineValidationResult {
+  chords: Chord[];
   issues: ChordValidationIssue[];
+  isStrictChordLine: boolean;
   isChordLike: boolean;
 }
 
@@ -29,66 +73,10 @@ export class TextRenderingService {
   private transposeService = inject(TransposeService);
 
   private readonly regexSection = /^\s*(Strophe|Refrain|Bridge)\b/i;
-  private readonly chordRoots = [
-    'C#',
-    'Db',
-    'D#',
-    'Eb',
-    'F#',
-    'Gb',
-    'G#',
-    'Ab',
-    'A#',
-    'C',
-    'D',
-    'E',
-    'F',
-    'G',
-    'A',
-    'B',
-    'H',
-    'c#',
-    'db',
-    'd#',
-    'eb',
-    'f#',
-    'gb',
-    'g#',
-    'ab',
-    'a#',
-    'c',
-    'd',
-    'e',
-    'f',
-    'g',
-    'a',
-    'b',
-    'h',
-  ] as const;
+  private readonly chordRoots = CANONICAL_CHORD_ROOTS;
   private readonly suffixKeywords = ['moll', 'verm', 'maj', 'min', 'dur', 'dim', 'aug', 'sus', 'add', 'm'] as const;
   private readonly suffixChars = new Set(['#', 'b', '+', '-', '(', ')']);
-  private readonly alternativeChordRoots: Record<string, string> = {
-    Ais: 'A#',
-    ais: 'a#',
-    As: 'Ab',
-    as: 'ab',
-    Cis: 'C#',
-    cis: 'c#',
-    Des: 'Db',
-    des: 'db',
-    Dis: 'D#',
-    dis: 'd#',
-    Es: 'Eb',
-    es: 'eb',
-    Fis: 'F#',
-    fis: 'f#',
-    Ges: 'Gb',
-    ges: 'gb',
-    Gis: 'G#',
-    gis: 'g#',
-    Hb: 'B',
-    hb: 'b',
-  };
+  private readonly alternativeChordRoots = ALTERNATIVE_CHORD_ROOTS;
 
   public parse(text: string, transpose: TransposeMode | null, withComments = true): Section[] {
     if (!text) {
@@ -153,14 +141,15 @@ export class TextRenderingService {
   private getLineOfLineText(text: string, transpose: TransposeMode | null, lineNumber?: number): Line | null {
     if (!text) return null;
 
-    const chords = this.readChords(text);
-    const validationResult = lineNumber ? this.getChordLineValidationResult(text, lineNumber) : {issues: [], isChordLike: false};
+    const validationResult = lineNumber
+      ? this.getChordLineValidationResult(text, lineNumber)
+      : {chords: [], issues: [], isStrictChordLine: false, isChordLike: false};
     const validationIssues = validationResult.issues;
-    const hasMatches = chords.length > 0;
+    const hasMatches = validationResult.isStrictChordLine;
     const isChordLikeLine = hasMatches || validationResult.isChordLike;
     const type = isChordLikeLine ? LineType.chord : LineType.text;
 
-    const line: Line = {type, text, chords: hasMatches ? chords : null, lineNumber};
+    const line: Line = {type, text, chords: hasMatches ? validationResult.chords : null, lineNumber};
     if (validationIssues.length > 0 || (!hasMatches && isChordLikeLine)) {
       return line;
     }
@@ -189,7 +178,7 @@ export class TextRenderingService {
     return null;
   }
 
-  private readChords(chordLine: string): Chord[] {
+  private getParsedChords(chordLine: string): Chord[] {
     const chords: Chord[] = [];
     const tokens = chordLine.match(/\S+/g) ?? [];
 
@@ -201,14 +190,12 @@ export class TextRenderingService {
       }
     }
 
-    const chordCount = chords.reduce((acc: number, cur: Chord) => acc + cur.length, 0);
-    const lineCount = chordLine.replace(/\s/g, '').length;
-    const isChordLine = chordCount * 1.2 > lineCount;
-    return isChordLine ? chords : [];
+    return chords;
   }
 
   private getChordLineValidationResult(line: string, lineNumber: number): ChordLineValidationResult {
     const tokens = line.match(/\S+/g) ?? [];
+    const chords = this.getParsedChords(line);
     const parsedTokens = tokens
       .map(token => ({
         token,
@@ -217,14 +204,16 @@ export class TextRenderingService {
 
     const recognizedTokens = parsedTokens.filter((entry): entry is {token: string; parsed: ParsedValidationToken} => entry.parsed !== null);
 
+    const strictChordCount = chords.reduce((sum, chord) => sum + chord.length, 0);
     const parsedLength = recognizedTokens.reduce((sum, entry) => sum + entry.token.length, 0);
     const compactLineLength = line.replace(/\s/g, '').length;
+    const isStrictChordLine = compactLineLength > 0 && strictChordCount * 1.2 > compactLineLength;
     const strictlyChordLike = compactLineLength > 0 && parsedLength * 1.2 > compactLineLength;
     const heuristicallyChordLike = tokens.length >= 2 && recognizedTokens.length >= Math.ceil(tokens.length * 0.6);
     const isChordLike = strictlyChordLike || heuristicallyChordLike;
 
     if (!isChordLike) {
-      return {issues: [], isChordLike: false};
+      return {chords, issues: [], isStrictChordLine, isChordLike: false};
     }
 
     const issues: ChordValidationIssue[] = [];
@@ -233,6 +222,7 @@ export class TextRenderingService {
     }
 
     return {
+      chords,
       issues: [
         ...issues,
         ...parsedTokens
@@ -245,6 +235,7 @@ export class TextRenderingService {
         })
           .filter((issue): issue is ChordValidationIssue => issue !== null),
       ],
+      isStrictChordLine,
       isChordLike: true,
     };
   }
@@ -492,7 +483,7 @@ export class TextRenderingService {
     }
 
     const slashChord = parsed.slashChord
-      ? (this.isMinorRoot(root) ? this.toMinorRoot(parsed.slashChord) : this.toMajorRoot(parsed.slashChord))
+      ? this.toMajorRoot(parsed.slashChord)
       : null;
 
     return parsed.prefix + root + suffix + (slashChord ? `/${slashChord}` : '') + parsed.tokenSuffix;
@@ -559,11 +550,35 @@ export class TextRenderingService {
   }
 
   private splitTokenDecorators(token: string): {prefix: string; core: string; suffix: string} {
-    const prefixMatch = token.match(/^\(+/);
-    const suffixMatch = token.match(/\)+$/);
-    const prefix = prefixMatch?.[0] ?? '';
-    const suffix = suffixMatch?.[0] ?? '';
-    const core = token.slice(prefix.length, token.length - suffix.length);
+    let prefix = '';
+    let suffix = '';
+    let core = token;
+
+    while (core.startsWith('(') && !this.isFullyWrappedByOuterParentheses(core)) {
+      const matchingClosingParen = this.findMatchingClosingParen(core, 0);
+      if (matchingClosingParen !== -1) {
+        break;
+      }
+
+      prefix += '(';
+      core = core.slice(1);
+    }
+
+    while (core.endsWith(')') && !this.isFullyWrappedByOuterParentheses(core)) {
+      const matchingOpeningParen = this.findMatchingOpeningParen(core, core.length - 1);
+      if (matchingOpeningParen !== -1) {
+        break;
+      }
+
+      suffix = ')' + suffix;
+      core = core.slice(0, -1);
+    }
+
+    while (this.isFullyWrappedByOuterParentheses(core)) {
+      prefix += '(';
+      suffix = ')' + suffix;
+      core = core.slice(1, -1);
+    }
 
     return {
       prefix,
@@ -572,6 +587,52 @@ export class TextRenderingService {
     };
   }
 
+  private isFullyWrappedByOuterParentheses(value: string): boolean {
+    if (!value.startsWith('(') || !value.endsWith(')')) {
+      return false;
+    }
+
+    return this.findMatchingClosingParen(value, 0) === value.length - 1;
+  }
+
+  private findMatchingClosingParen(value: string, start: number): number {
+    let depth = 0;
+    for (let i = start; i < value.length; i++) {
+      if (value[i] === '(') {
+        depth++;
+      } else if (value[i] === ')') {
+        depth--;
+        if (depth === 0) {
+          return i;
+        }
+        if (depth < 0) {
+          return -1;
+        }
+      }
+    }
+
+    return -1;
+  }
+
+  private findMatchingOpeningParen(value: string, end: number): number {
+    let depth = 0;
+    for (let i = end; i >= 0; i--) {
+      if (value[i] === ')') {
+        depth++;
+      } else if (value[i] === '(') {
+        depth--;
+        if (depth === 0) {
+          return i;
+        }
+        if (depth < 0) {
+          return -1;
+        }
+      }
+    }
+
+    return -1;
+  }
+
   private parseChordAddDescriptor(suffix: string | null): ChordAddDescriptor | null {
     if (!suffix) {
       return null;
diff --git a/src/app/modules/songs/song-list/song-list.component.html b/src/app/modules/songs/song-list/song-list.component.html
index c5c1599..5d34a00 100644
--- a/src/app/modules/songs/song-list/song-list.component.html
+++ b/src/app/modules/songs/song-list/song-list.component.html
@@ -7,7 +7,12 @@
       @for (song of songs; track trackBy($index, song)) {
         <div [routerLink]="song.id" class="list-item">
           <div class="number">{{ song.number }}</div>
-          <div>{{ song.title }}</div>
+          <div class="title">
+            <span>{{ song.title }}</span>
+            @if (song.hasChordValidationIssues) {
+              <span class="validation-star" title="Akkord-Validierungsfehler vorhanden">*</span>
+            }
+          </div>
           <div>
             <ng-container *appRole="['contributor']">
               @if (song.status === 'draft') {
diff --git a/src/app/modules/songs/song-list/song-list.component.less b/src/app/modules/songs/song-list/song-list.component.less
index 8aee505..a5dd51a 100644
--- a/src/app/modules/songs/song-list/song-list.component.less
+++ b/src/app/modules/songs/song-list/song-list.component.less
@@ -27,6 +27,15 @@
   text-align: right;
 }
 
+.title {
+  gap: 6px;
+}
+
+.validation-star {
+  color: var(--danger);
+  font-weight: bold;
+}
+
 .neutral, .warning, .success {
   width: 30px;
 }
diff --git a/src/app/modules/songs/song-list/song-list.component.ts b/src/app/modules/songs/song-list/song-list.component.ts
index f4f7129..f495d7e 100644
--- a/src/app/modules/songs/song-list/song-list.component.ts
+++ b/src/app/modules/songs/song-list/song-list.component.ts
@@ -9,6 +9,7 @@ import {filterSong} from '../../../services/filter.helper';
 import {FilterValues} from './filter/filter-values';
 import {ScrollService} from '../../../services/scroll.service';
 import {faBalanceScaleRight, faCheck, faPencilRuler} from '@fortawesome/free-solid-svg-icons';
+import {TextRenderingService} from '../services/text-rendering.service';
 import {AsyncPipe} from '@angular/common';
 import {ListHeaderComponent} from '../../../widget-modules/components/list-header/list-header.component';
 import {FilterComponent} from './filter/filter.component';
@@ -16,6 +17,10 @@ import {CardComponent} from '../../../widget-modules/components/card/card.compon
 import {RoleDirective} from '../../../services/user/role.directive';
 import {FaIconComponent} from '@fortawesome/angular-fontawesome';
 
+interface SongListItem extends Song {
+  hasChordValidationIssues: boolean;
+}
+
 @Component({
   selector: 'app-songs',
   templateUrl: './song-list.component.html',
@@ -28,15 +33,22 @@ export class SongListComponent implements OnInit, OnDestroy {
   private songService = inject(SongService);
   private activatedRoute = inject(ActivatedRoute);
   private scrollService = inject(ScrollService);
+  private textRenderingService = inject(TextRenderingService);
 
   public anyFilterActive = false;
-  public songs$: Observable<Song[]> = combineLatest([
+  public songs$: Observable<SongListItem[]> = combineLatest([
     this.activatedRoute.queryParams.pipe(map(_ => _ as FilterValues)),
     this.songService.list$().pipe(map(songs => [...songs].sort((a, b) => a.number - b.number))),
   ]).pipe(
     map(([filter, songs]) => {
       this.anyFilterActive = this.checkIfFilterActive(filter);
-      return songs.filter(song => this.filter(song, filter)).sort((a, b) => a.title?.localeCompare(b.title));
+      return songs
+        .filter(song => this.filter(song, filter))
+        .map(song => ({
+          ...song,
+          hasChordValidationIssues: this.textRenderingService.validateChordNotation(song.text ?? '').length > 0,
+        }))
+        .sort((a, b) => a.title?.localeCompare(b.title));
     })
   );
   public faLegal = faBalanceScaleRight;
@@ -52,7 +64,7 @@ export class SongListComponent implements OnInit, OnDestroy {
     this.scrollService.storeScrollPositionFor('songlist');
   }
 
-  public trackBy = (index: number, show: Song) => show.id;
+  public trackBy = (index: number, show: SongListItem) => show.id;
 
   private filter(song: Song, filter: FilterValues): boolean {
     let baseFilter = filterSong(song, filter.q);
diff --git a/src/app/modules/songs/song/edit/edit-song/edit-song.component.html b/src/app/modules/songs/song/edit/edit-song/edit-song.component.html
index 16d1747..61aef39 100644
--- a/src/app/modules/songs/song/edit/edit-song/edit-song.component.html
+++ b/src/app/modules/songs/song/edit/edit-song/edit-song.component.html
@@ -73,7 +73,7 @@
       @if (songtextFocus) {
         <div class="song-text-help">
           <h3>Vorschau</h3>
-          <app-song-text [invalidChordIssues]="chordValidationIssues" [text]="form.value.text" chordMode="show"></app-song-text>
+          <app-song-text [text]="form.value.text" [validateChordNotation]="true" chordMode="show"></app-song-text>
           <h3>Hinweise zur Bearbeitung</h3>
           <h4>Aufbau</h4>
           Der Liedtext wird hintereinander weg geschrieben. Dabei werden Strophen,
diff --git a/src/app/modules/songs/song/edit/edit-song/edit-song.component.less b/src/app/modules/songs/song/edit/edit-song/edit-song.component.less
index d7ddd28..d92b086 100644
--- a/src/app/modules/songs/song/edit/edit-song/edit-song.component.less
+++ b/src/app/modules/songs/song/edit/edit-song/edit-song.component.less
@@ -4,6 +4,7 @@
 
   > * {
     width: 100%;
+    box-sizing: border-box;
   }
 
   .fourth {
@@ -65,4 +66,8 @@ h4 {
     border-radius: 4px;
     background: rgba(125, 25, 25, 0.08);
   }
+
+  h3 {
+    margin: 0;
+  }
 }
diff --git a/src/app/modules/songs/song/song.component.html b/src/app/modules/songs/song/song.component.html
index acea852..53232e8 100644
--- a/src/app/modules/songs/song/song.component.html
+++ b/src/app/modules/songs/song/song.component.html
@@ -3,7 +3,7 @@
     <app-card
       [heading]="song.number + ' - ' + song.title"
       closeLink="../"
-      >
+    >
       <div class="song">
         <div>
           <div *appRole="['leader', 'contributor']" class="detail">
@@ -21,7 +21,7 @@
                 <a
                   href="https://songselect.ccli.com/Songs/{{ song.legalOwnerId }}"
                   target="_blank"
-                  >
+                >
                   CCLI Nummer: {{ song.legalOwnerId }}
                 </a>
               </div>
@@ -48,15 +48,16 @@
             [chordMode]="user.chordMode"
             [showSwitch]="true"
             [text]="song.text"
+            [validateChordNotation]="true"
           ></app-song-text>
         }
         <mat-chip-listbox
           *appRole="['leader', 'contributor']"
           aria-label="Attribute"
-          >
+        >
           @for (flag of getFlags(song.flags); track flag) {
             <mat-chip-option>{{
-              flag
+                flag
               }}
             </mat-chip-option>
           }
@@ -70,10 +71,10 @@
           (click)="onDelete(song.id)"
           *appRole="['admin']"
           [icon]="faDelete"
-          >Löschen
+        >Löschen
         </app-button>
         <app-button *appRole="['contributor']" [icon]="faEdit" routerLink="edit"
-          >Bearbeiten
+        >Bearbeiten
         </app-button>
         <ng-container *appRole="['leader']">
           <app-button [icon]="faFileCirclePlus" [matMenuTriggerFor]="menu">
diff --git a/src/app/widget-modules/components/song-text/song-text.component.html b/src/app/widget-modules/components/song-text/song-text.component.html
index cb3a0ae..ca451c6 100644
--- a/src/app/widget-modules/components/song-text/song-text.component.html
+++ b/src/app/widget-modules/components/song-text/song-text.component.html
@@ -28,7 +28,7 @@
               class="line"
               >
               @for (segment of getDisplaySegments(line); track $index) {
-                <span [class.invalid-chord-token]="segment.invalid">{{ segment.text }}</span>
+                <span [class.invalid-chord-token]="segment.invalid" [class.invalid-tab-token]="segment.isTab">{{ segment.text }}</span>
               }
             </div>
           }
@@ -77,7 +77,7 @@
               class="line"
               >
               @for (segment of getDisplaySegments(line, true); track $index) {
-                <span [class.invalid-chord-token]="segment.invalid">{{ segment.text }}</span>
+                <span [class.invalid-chord-token]="segment.invalid" [class.invalid-tab-token]="segment.isTab">{{ segment.text }}</span>
               }
             </div>
           }
diff --git a/src/app/widget-modules/components/song-text/song-text.component.less b/src/app/widget-modules/components/song-text/song-text.component.less
index 742b352..5593226 100644
--- a/src/app/widget-modules/components/song-text/song-text.component.less
+++ b/src/app/widget-modules/components/song-text/song-text.component.less
@@ -39,6 +39,15 @@
   text-shadow: none;
 }
 
+.invalid-tab-token {
+  display: inline-block;
+  min-width: 1.5ch;
+  text-align: center;
+  background: rgba(180, 35, 24, 0.12);
+  border-radius: 3px;
+  font-weight: bold;
+}
+
 .menu {
   position: absolute;
   right: -10px;
diff --git a/src/app/widget-modules/components/song-text/song-text.component.ts b/src/app/widget-modules/components/song-text/song-text.component.ts
index afeee0f..644483c 100644
--- a/src/app/widget-modules/components/song-text/song-text.component.ts
+++ b/src/app/widget-modules/components/song-text/song-text.component.ts
@@ -17,6 +17,7 @@ export type ChordMode = 'show' | 'hide' | 'onlyFirst';
 interface DisplaySegment {
   text: string;
   invalid: boolean;
+  isTab: boolean;
 }
 
 @Component({
@@ -42,6 +43,7 @@ export class SongTextComponent implements OnInit {
   public faLines = faGripLines;
   public offset = 0;
   public iChordMode: ChordMode = 'hide';
+  public showValidationIssues = false;
   private invalidChordIssuesByLine = new Map<number, ChordValidationIssue[]>();
   private iText = '';
   private iTranspose: TransposeMode | null = null;
@@ -64,14 +66,9 @@ export class SongTextComponent implements OnInit {
   }
 
   @Input()
-  public set invalidChordIssues(value: ChordValidationIssue[] | null) {
-    const issuesByLine = new Map<number, ChordValidationIssue[]>();
-    (value ?? []).forEach(issue => {
-      const lineIssues = issuesByLine.get(issue.lineNumber) ?? [];
-      lineIssues.push(issue);
-      issuesByLine.set(issue.lineNumber, lineIssues);
-    });
-    this.invalidChordIssuesByLine = issuesByLine;
+  public set validateChordNotation(value: boolean) {
+    this.showValidationIssues = value;
+    this.updateValidationIssues();
     this.cRef.markForCheck();
   }
 
@@ -129,41 +126,45 @@ export class SongTextComponent implements OnInit {
     const text = trim ? line.text.trim() : this.transform(line.text);
     const lineNumber = line.lineNumber;
     if (!lineNumber) {
-      return [{text, invalid: false}];
+      return [{text, invalid: false, isTab: false}];
     }
 
     const issues = this.invalidChordIssuesByLine.get(lineNumber);
     if (!issues || issues.length === 0) {
-      return [{text, invalid: false}];
+      return [{text, invalid: false, isTab: false}];
     }
 
-    const ranges: Array<{start: number; end: number}> = [];
+    const ranges: Array<{start: number; end: number; isTab: boolean}> = [];
     let searchStart = 0;
     issues.forEach(issue => {
       const index = text.indexOf(issue.token, searchStart);
       if (index === -1) {
         return;
       }
-      ranges.push({start: index, end: index + issue.token.length});
+      ranges.push({start: index, end: index + issue.token.length, isTab: issue.reason === 'tab_character'});
       searchStart = index + issue.token.length;
     });
 
     if (ranges.length === 0) {
-      return [{text, invalid: false}];
+      return [{text, invalid: false, isTab: false}];
     }
 
     const segments: DisplaySegment[] = [];
     let cursor = 0;
     ranges.forEach(range => {
       if (range.start > cursor) {
-        segments.push({text: text.slice(cursor, range.start), invalid: false});
+        segments.push({text: text.slice(cursor, range.start), invalid: false, isTab: false});
       }
-      segments.push({text: text.slice(range.start, range.end), invalid: true});
+      segments.push({
+        text: range.isTab ? '⇥' : text.slice(range.start, range.end),
+        invalid: true,
+        isTab: range.isTab,
+      });
       cursor = range.end;
     });
 
     if (cursor < text.length) {
-      segments.push({text: text.slice(cursor), invalid: false});
+      segments.push({text: text.slice(cursor), invalid: false, isTab: false});
     }
 
     return segments;
@@ -176,6 +177,7 @@ export class SongTextComponent implements OnInit {
   private render() {
     this.offset = 0;
     this.sections = [];
+    this.updateValidationIssues();
     if (this.fullscreen) {
       setTimeout(() => {
         this.sections = this.textRenderingService.parse(this.iText, this.iTranspose, this.showComments);
@@ -187,6 +189,21 @@ export class SongTextComponent implements OnInit {
     }
   }
 
+  private updateValidationIssues(): void {
+    if (!this.showValidationIssues) {
+      this.invalidChordIssuesByLine = new Map<number, ChordValidationIssue[]>();
+      return;
+    }
+
+    const issuesByLine = new Map<number, ChordValidationIssue[]>();
+    this.textRenderingService.validateChordNotation(this.iText, this.showComments).forEach(issue => {
+      const lineIssues = issuesByLine.get(issue.lineNumber) ?? [];
+      lineIssues.push(issue);
+      issuesByLine.set(issue.lineNumber, lineIssues);
+    });
+    this.invalidChordIssuesByLine = issuesByLine;
+  }
+
   private getNextChordMode(): ChordMode {
     switch (this.iChordMode) {
       case 'show':