Rewrite chapter parser for testability

2 files changed, 197 insertions, 0 deletions

diff --git a/core/src/test/java/de/danoeh/antennapod/core/util/id3reader/ChapterReaderTest.java b/core/src/test/java/de/danoeh/antennapod/core/util/id3reader/ChapterReaderTest.java
new file mode 100644
index 000000000..34580146e
--- /dev/null
+++ b/core/src/test/java/de/danoeh/antennapod/core/util/id3reader/ChapterReaderTest.java
@@ -0,0 +1,105 @@
+package de.danoeh.antennapod.core.util.id3reader;
+
+import de.danoeh.antennapod.core.feed.Chapter;
+import de.danoeh.antennapod.core.feed.ID3Chapter;
+import de.danoeh.antennapod.core.util.id3reader.model.FrameHeader;
+import org.apache.commons.io.input.CountingInputStream;
+import org.junit.Test;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+
+import static de.danoeh.antennapod.core.util.id3reader.Id3ReaderTest.concat;
+import static de.danoeh.antennapod.core.util.id3reader.Id3ReaderTest.generateFrameHeader;
+import static de.danoeh.antennapod.core.util.id3reader.Id3ReaderTest.generateId3Header;
+import static org.junit.Assert.assertEquals;
+
+public class ChapterReaderTest {
+    private static final byte CHAPTER_WITHOUT_SUBFRAME_START_TIME = 23;
+    private static final byte[] CHAPTER_WITHOUT_SUBFRAME = {
+            'C', 'H', '1', 0, // String ID for mapping to CTOC
+            0, 0, 0, CHAPTER_WITHOUT_SUBFRAME_START_TIME, // Start time
+            0, 0, 0, 0, // End time
+            0, 0, 0, 0, // Start offset
+            0, 0, 0, 0 // End offset
+    };
+
+    @Test
+    public void testReadFullTagWithChapter() throws IOException, ID3ReaderException {
+        byte[] chapter = concat(
+                generateFrameHeader(ChapterReader.FRAME_ID_CHAPTER, CHAPTER_WITHOUT_SUBFRAME.length),
+                CHAPTER_WITHOUT_SUBFRAME);
+        byte[] data = concat(
+                generateId3Header(chapter.length),
+                chapter);
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(data));
+        ChapterReader reader = new ChapterReader(inputStream);
+        reader.readInputStream();
+        assertEquals(1, reader.getChapters().size());
+        assertEquals(CHAPTER_WITHOUT_SUBFRAME_START_TIME, reader.getChapters().get(0).getStart());
+    }
+
+    @Test
+    public void testReadFullTagWithMultipleChapters() throws IOException, ID3ReaderException {
+        byte[] chapter = concat(
+                generateFrameHeader(ChapterReader.FRAME_ID_CHAPTER, CHAPTER_WITHOUT_SUBFRAME.length),
+                CHAPTER_WITHOUT_SUBFRAME);
+        byte[] data = concat(
+                generateId3Header(2 * chapter.length),
+                chapter,
+                chapter);
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(data));
+        ChapterReader reader = new ChapterReader(inputStream);
+        reader.readInputStream();
+        assertEquals(2, reader.getChapters().size());
+        assertEquals(CHAPTER_WITHOUT_SUBFRAME_START_TIME, reader.getChapters().get(0).getStart());
+        assertEquals(CHAPTER_WITHOUT_SUBFRAME_START_TIME, reader.getChapters().get(1).getStart());
+    }
+
+    @Test
+    public void testReadChapterWithoutSubframes() throws IOException, ID3ReaderException {
+        FrameHeader header = new FrameHeader(ChapterReader.FRAME_ID_CHAPTER,
+                CHAPTER_WITHOUT_SUBFRAME.length, (short) 0);
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(CHAPTER_WITHOUT_SUBFRAME));
+        Chapter chapter = new ChapterReader(inputStream).readChapter(header);
+        assertEquals(CHAPTER_WITHOUT_SUBFRAME_START_TIME, chapter.getStart());
+    }
+
+    @Test
+    public void testReadChapterWithTitle() throws IOException, ID3ReaderException {
+        byte[] title = {
+            ID3Reader.ENCODING_ISO,
+            'H', 'e', 'l', 'l', 'o', // Title
+            0 // Null-terminated
+        };
+        byte[] chapterData = concat(
+            CHAPTER_WITHOUT_SUBFRAME,
+            generateFrameHeader(ChapterReader.FRAME_ID_TITLE, title.length),
+            title);
+        FrameHeader header = new FrameHeader(ChapterReader.FRAME_ID_CHAPTER, chapterData.length, (short) 0);
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(chapterData));
+        ChapterReader reader = new ChapterReader(inputStream);
+        Chapter chapter = reader.readChapter(header);
+        assertEquals(CHAPTER_WITHOUT_SUBFRAME_START_TIME, chapter.getStart());
+        assertEquals("Hello", chapter.getTitle());
+    }
+
+    @Test
+    public void testReadTitleWithGarbage() throws IOException, ID3ReaderException {
+        byte[] titleSubframeContent = {
+                ID3Reader.ENCODING_ISO,
+                'A', // Title
+                0, // Null-terminated
+                42, 42, 42, 42 // Garbage, should be ignored
+        };
+        FrameHeader header = new FrameHeader(ChapterReader.FRAME_ID_TITLE, titleSubframeContent.length, (short) 0);
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(titleSubframeContent));
+        ChapterReader reader = new ChapterReader(inputStream);
+        Chapter chapter = new ID3Chapter("", 0);
+        reader.readChapterSubFrame(header, chapter);
+        assertEquals("A", chapter.getTitle());
+
+        // Should skip the garbage and point to the next frame
+        assertEquals(titleSubframeContent.length, reader.getPosition());
+    }
+}
diff --git a/core/src/test/java/de/danoeh/antennapod/core/util/id3reader/Id3ReaderTest.java b/core/src/test/java/de/danoeh/antennapod/core/util/id3reader/Id3ReaderTest.java
new file mode 100644
index 000000000..53e338416
--- /dev/null
+++ b/core/src/test/java/de/danoeh/antennapod/core/util/id3reader/Id3ReaderTest.java
@@ -0,0 +1,92 @@
+package de.danoeh.antennapod.core.util.id3reader;
+
+import de.danoeh.antennapod.core.util.id3reader.model.FrameHeader;
+import de.danoeh.antennapod.core.util.id3reader.model.TagHeader;
+import org.apache.commons.io.input.CountingInputStream;
+import org.junit.Test;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
+public class Id3ReaderTest {
+    @Test
+    public void testReadString() throws IOException {
+        byte[] data = {
+            ID3Reader.ENCODING_ISO,
+            'T', 'e', 's', 't',
+            0 // Null-terminated
+        };
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(data));
+        String string = new ID3Reader(inputStream).readEncodingAndString(1000);
+        assertEquals("Test", string);
+    }
+
+    @Test
+    public void testReadUtf16WithBom() throws IOException {
+        byte[] data = {
+            ID3Reader.ENCODING_UTF16_WITH_BOM,
+            (byte) 0xff, (byte) 0xfe, // BOM
+            'A', 0, 'B', 0, 'C', 0,
+            0, 0, // Null-terminated
+        };
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(data));
+        String string = new ID3Reader(inputStream).readEncodingAndString(1000);
+        assertEquals("ABC", string);
+    }
+
+    @Test
+    public void testReadTagHeader() throws IOException, ID3ReaderException {
+        byte[] data = generateId3Header(23);
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(data));
+        TagHeader header = new ID3Reader(inputStream).readTagHeader();
+        assertEquals("ID3", header.getId());
+        assertEquals(42, header.getVersion());
+        assertEquals(23, header.getSize());
+    }
+
+    @Test
+    public void testReadFrameHeader() throws IOException {
+        byte[] data = generateFrameHeader("CHAP", 42);
+        CountingInputStream inputStream = new CountingInputStream(new ByteArrayInputStream(data));
+        FrameHeader header = new ID3Reader(inputStream).readFrameHeader();
+        assertEquals("CHAP", header.getId());
+        assertEquals(42, header.getSize());
+    }
+
+    public static byte[] generateFrameHeader(String id, int size) {
+        return concat(
+            id.getBytes(StandardCharsets.ISO_8859_1), // Frame ID
+            new byte[] {
+                (byte) (size >> 24), (byte) (size >> 16),
+                (byte) (size >> 8), (byte) (size), // Size
+                0, 0 // Flags
+            });
+    }
+
+    static byte[] generateId3Header(int size) {
+        return new byte[] {
+                'I', 'D', '3', // Identifier
+                0, 42, // Version
+                0, // Flags
+                (byte) (size >> 24), (byte) (size >> 16),
+                (byte) (size >> 8), (byte) (size), // Size
+        };
+    }
+
+    static byte[] concat(byte[]... arrays) {
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        try {
+            for (byte[] array : arrays) {
+                outputStream.write(array);
+            }
+        } catch (IOException e) {
+            fail(e.getMessage());
+        }
+        return outputStream.toByteArray();
+    }
+}