Transpose

generator/practice/generate.py

@@ -4,6 +4,7 @@ from pathlib import Path
 
 from generator.score import copy_source_voices, make_arranged_document, make_measure, reidentify, slugify, source_staff, write_json
 from generator.musicxml import load_musicxml
+from generator.practice.guitar import transpose_guitar_practice
 from generator.transposition import TARGET_KEYS, transpose_document
 
 def practice_document(document: dict) -> dict:
@@ -39,23 +40,23 @@ def key_file_name(key: str) -> str:
   return slugify(key.replace("#", "sharp")) + ".json"
 
 def generate_chord_practice(source_path: Path, source_root: Path, output_dir: Path) -> int:
-  document = practice_document(load_musicxml(source_path))
-  metadata = document.get("metadata", {})
-  key = str(metadata.get("key_signature", "C") if isinstance(metadata, dict) else "C")
-  relative = source_path.relative_to(source_root)
-  lesson_group = relative.parent.name
-  exercise_id = slugify(source_path.stem)
-  write_json(output_dir / "chord" / lesson_group / exercise_id / key_file_name(key), document)
-  return 1
+  return generate_key_variants(source_path, source_root, output_dir, 'chord')
 
 def generate_melody_practice(source_path: Path, source_root: Path, output_dir: Path) -> int:
+  return generate_key_variants(source_path, source_root, output_dir, 'melody')
+
+def generate_key_variants(source_path: Path, source_root: Path, output_dir: Path, practice_type: str) -> int:
   base_document = practice_document(load_musicxml(source_path))
   relative = source_path.relative_to(source_root)
   lesson_group = relative.parent.name
   exercise_id = slugify(source_path.stem)
   count = 0
   for key in TARGET_KEYS:
-    write_json(output_dir / "melody" / lesson_group / exercise_id / key_file_name(key), transpose_document(base_document, key))
+    try:
+      variant = transpose_guitar_practice(base_document, key) if practice_type == 'chord' else transpose_document(base_document, key)
+    except ValueError as error:
+      raise ValueError(f'{source_path}, target key {key}: {error}') from error
+    write_json(output_dir / practice_type / lesson_group / exercise_id / key_file_name(key), variant)
     count += 1
   return count