3 files changed, 99 insertions, 2 deletions
diff --git a/tests/test_audio.py b/tests/test_audio.py
index a629224..29bf4ea 100644
--- a/tests/test_audio.py
+++ b/tests/test_audio.py
@@ -1,11 +1,11 @@
-"""Tests for audio helpers: speed parameters and chunk cleanup."""
+"""Tests for audio helpers: speed parameters, chunk cleanup, and encoding."""
 
 import tempfile
 import unittest
 from pathlib import Path
 
 from converter import config
-from converter.audio import cleanup_chunks, speed_export_params
+from converter.audio import _encode_args, build_ffmetadata, cleanup_chunks, speed_export_params
 
 
 class SpeedExportParamsTests(unittest.TestCase):
@@ -52,6 +52,48 @@ class CleanupChunksTests(unittest.TestCase):
             self.assertFalse((chunks_dir / "chunk_0002.wav").exists())
             self.assertTrue((chunks_dir / "keep.txt").exists())
 
+    def test_removes_chapter_files(self):
+        with tempfile.TemporaryDirectory() as tmp:
+            chunks_dir = Path(tmp)
+            (chunks_dir / "chapter_0001.m4b").write_bytes(b"stale")
+            (chunks_dir / "chunk_0001.wav").write_bytes(b"stale")
+
+            original = config.CHUNKS_FOLDER
+            config.CHUNKS_FOLDER = chunks_dir
+            try:
+                cleanup_chunks()
+            finally:
+                config.CHUNKS_FOLDER = original
+
+            self.assertFalse((chunks_dir / "chapter_0001.m4b").exists())
+            self.assertFalse((chunks_dir / "chunk_0001.wav").exists())
+
+
+class EncodeArgsTests(unittest.TestCase):
+    def test_mp3_uses_bitrate_only(self):
+        self.assertEqual(_encode_args("mp3"), ["-b:a", config.AUDIO_BITRATE])
+
+    def test_m4b_uses_aac(self):
+        self.assertEqual(_encode_args("m4b"), ["-c:a", "aac", "-b:a", config.AUDIO_BITRATE])
+
+
+class BuildFFMetadataTests(unittest.TestCase):
+    def test_writes_chapters(self):
+        chapters = [(0, 1200, "One"), (1200, 2500, "Two")]
+        with tempfile.TemporaryDirectory() as tmp:
+            path = Path(tmp) / "meta.txt"
+            build_ffmetadata(chapters, path)
+            content = path.read_text(encoding="utf-8")
+
+        self.assertTrue(content.startswith(";FFMETADATA1\n"))
+        self.assertIn("[CHAPTER]", content)
+        self.assertIn("TIMEBASE=1/1000", content)
+        self.assertIn("START=0", content)
+        self.assertIn("END=1200", content)
+        self.assertIn("title=One", content)
+        self.assertIn("START=1200", content)
+        self.assertIn("title=Two", content)
+
 
 if __name__ == "__main__":
     unittest.main()
diff --git a/tests/test_converter.py b/tests/test_converter.py
new file mode 100644
index 0000000..1235dda
--- /dev/null
+++ b/tests/test_converter.py
@@ -0,0 +1,21 @@
+"""Tests for the audiobook converter orchestration helpers."""
+
+import unittest
+
+from converter.converter import AudiobookConverter
+
+
+class SanitizeFilenameTests(unittest.TestCase):
+    def test_removes_invalid_characters(self):
+        self.assertEqual(AudiobookConverter._sanitize_filename('A "bad" name: here'),
+                         "A bad name here")
+
+    def test_collapses_whitespace(self):
+        self.assertEqual(AudiobookConverter._sanitize_filename("  spaced\tout  "), "spaced out")
+
+    def test_empty_falls_back(self):
+        self.assertEqual(AudiobookConverter._sanitize_filename("///"), "chapter")
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/tests/test_extractors.py b/tests/test_extractors.py
index c497267..09b688e 100644
--- a/tests/test_extractors.py
+++ b/tests/test_extractors.py
@@ -90,5 +90,39 @@ class EpubExtractionTests(unittest.TestCase):
                         text.index("Second chapter text."))
 
 
+class ExtractSectionsTests(unittest.TestCase):
+    def setUp(self):
+        try:
+            import ebooklib  # noqa: F401
+        except ImportError:
+            self.skipTest("ebooklib not installed")
+
+    def test_epub_sections_split_on_chapters(self):
+        from converter.extractors import extract_sections
+
+        with tempfile.TemporaryDirectory() as tmp:
+            path = Path(tmp) / "book.epub"
+            _build_test_epub(path)
+            sections = extract_sections(path)
+
+        self.assertEqual(len(sections), 2)
+        self.assertEqual(sections[0].title, "One")
+        self.assertEqual(sections[1].title, "Two")
+        self.assertIn("First chapter text.", sections[0].text)
+        self.assertIn("Second chapter text.", sections[1].text)
+
+    def test_txt_is_single_section(self):
+        from converter.extractors import extract_sections
+
+        with tempfile.TemporaryDirectory() as tmp:
+            path = Path(tmp) / "book.txt"
+            path.write_text("Hello world.", encoding="utf-8")
+            sections = extract_sections(path)
+
+        self.assertEqual(len(sections), 1)
+        self.assertEqual(sections[0].title, "book")
+        self.assertEqual(sections[0].text, "Hello world.")
+
+
 if __name__ == "__main__":
     unittest.main()