--- /dev/null
+/*
+ * Sonitus - BlockType.java - Copyright © 2013 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sonitus.io.flac;
+
+/**
+ * The type of a metadata block.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public enum BlockType {
+
+ /** A STREAMINFO block. */
+ STREAMINFO {
+ @Override
+ public Data createData(byte[] content) {
+ return new StreamInfo(content);
+ }
+ },
+
+ /** A PADDING block. */
+ PADDING,
+
+ /** An APPLICATION block. */
+ APPLICATION,
+
+ /** A SEEKTABLE block. */
+ SEEKTABLE,
+
+ /** A VORBIS_COMMENT block. */
+ VORBIS_COMMENT,
+
+ /** A CUESHEET block. */
+ CUESHEET,
+
+ /** A PICTURE block. */
+ PICTURE,
+
+ /** A RESERVED block. */
+ RESERVED,
+
+ /** An INVALID block. */
+ INVALID;
+
+ //
+ // ACTIONS
+ //
+
+ /**
+ * Creates a {@link Data} object from the given byte array. Block type
+ * enumeration values can override this to return specialized parser objects.
+ *
+ * @param content
+ * The content of the metadata block
+ * @return The metadata block as a data object
+ */
+ public Data createData(byte[] content) {
+ return new Data(content);
+ }
+
+ //
+ // STATIC METHODS
+ //
+
+ /**
+ * Creates a block type from the given block type number.
+ *
+ * @param blockType
+ * The block type number
+ * @return The parsed block type
+ */
+ public static BlockType valueOf(int blockType) {
+ if ((blockType >= 0) && (blockType <= 6)) {
+ return values()[blockType];
+ }
+ if ((blockType > 6) && (blockType < 127)) {
+ return RESERVED;
+ }
+ return INVALID;
+ }
+
+}
--- /dev/null
+/*
+ * Sonitus - Data.java - Copyright © 2013 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sonitus.io.flac;
+
+import static com.google.common.io.ByteStreams.readFully;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * Accessor type that can parse the contents of a {@link MetadataBlock}.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class Data {
+
+ /** The content of the metadata block. */
+ private final byte[] content;
+
+ /**
+ * Creates a new data accessor.
+ *
+ * @param content
+ * The content of the metadata block
+ */
+ public Data(byte[] content) {
+ this.content = content;
+ }
+
+ //
+ // ACCESSORS
+ //
+
+ /**
+ * Returns the content of this metadata block.
+ *
+ * @return The content of the metadata block
+ */
+ public byte[] content() {
+ return content;
+ }
+
+ //
+ // SUBCLASS METHODS
+ //
+
+ /**
+ * Parses the given number of bits from the content of this metadata block,
+ * starting at the given byte offset and bit offset (bit 0 being the most
+ * significant bit).
+ *
+ * @param byteOffset
+ * The byte offset at which to start reading
+ * @param bitOffset
+ * The bit offset at which to start reading
+ * @param numberOfBits
+ * The number of bits to parse (should be <= 64)
+ * @return The parsed bits
+ */
+ protected long parseBits(int byteOffset, int bitOffset, int numberOfBits) {
+ long value = 0;
+ int currentByteOffset = byteOffset;
+ int currentBitOffset = bitOffset;
+ int bitsRemaining = numberOfBits;
+
+ while (bitsRemaining > 0) {
+ value = (value << Math.min(8, bitsRemaining)) | ((content[currentByteOffset] & (0xff >>> currentBitOffset)) >> (8 - currentBitOffset - Math.min(bitsRemaining, 8 - currentBitOffset)));
+ bitsRemaining -= Math.min(bitsRemaining, 8 - currentBitOffset);
+ currentBitOffset = 0;
+ currentByteOffset++;
+ }
+
+ return value;
+ }
+
+ //
+ // STATIC METHODS
+ //
+
+ /**
+ * Creates a new data accessor from the given input stream.
+ *
+ * @param inputStream
+ * The input stream to read the contents of the metadata block from
+ * @param blockType
+ * The type of the metadata block
+ * @param length
+ * The length of the metadata block
+ * @return The parsed metadata block
+ * @throws IOException
+ * if an I/O error occurs
+ */
+ public static Data parse(InputStream inputStream, BlockType blockType, int length) throws IOException {
+ byte[] buffer = new byte[length];
+ readFully(inputStream, buffer);
+ return blockType.createData(buffer);
+ }
+
+}
--- /dev/null
+/*
+ * Sonitus - Header.java - Copyright © 2013 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sonitus.io.flac;
+
+import static com.google.common.io.ByteStreams.readFully;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * Header for a {@link MetadataBlock}.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class Header {
+
+ /** Whether this metadata block is the last metadata block. */
+ private final boolean lastMetadataBlock;
+
+ /** The type of the metadata block. */
+ private final BlockType blockType;
+
+ /** The length of the metadata block. */
+ private final int length;
+
+ /**
+ * Creates a new metadata block header.
+ *
+ * @param lastMetadataBlock
+ * {@code true} if this metadata block is the last metadata block in the FLAC
+ * stream, {@code false} otherwise
+ * @param blockType
+ * The type of the metadata block
+ * @param length
+ * The length of the metadata block
+ */
+ private Header(boolean lastMetadataBlock, BlockType blockType, int length) {
+ this.lastMetadataBlock = lastMetadataBlock;
+ this.blockType = blockType;
+ this.length = length;
+ }
+
+ //
+ // ACCESSORS
+ //
+
+ /**
+ * Returns whether this metadata block is the last metadata block in the FLAC
+ * {@link Stream}.
+ *
+ * @return {@code true} if this metadata block is last metadata block in the
+ * FLAC stream, {@code false} otherwise
+ */
+ public boolean isLastMetadataBlock() {
+ return lastMetadataBlock;
+ }
+
+ /**
+ * Returns the type of the metadata block.
+ *
+ * @return The type of the metadata block
+ */
+ public BlockType blockType() {
+ return blockType;
+ }
+
+ /**
+ * Returns the length of the metadata block.
+ *
+ * @return The length of the metadata block
+ */
+ public int length() {
+ return length;
+ }
+
+ //
+ // STATIC METHODS
+ //
+
+ /**
+ * Parses a metadata block header from the current position of the given input
+ * stream.
+ *
+ * @param inputStream
+ * The input stream to parse the header from
+ * @return The parsed header
+ * @throws IOException
+ * if an I/O error occurs
+ */
+ public static Header parse(InputStream inputStream) throws IOException {
+ byte[] buffer = new byte[4];
+ readFully(inputStream, buffer);
+ boolean lastMetadataBlock = ((buffer[0] >> 7) & 0x01) != 0;
+ BlockType blockType = BlockType.valueOf(buffer[0] & 0x7f);
+ int length = ((buffer[1] & 0xff) << 16) | ((buffer[2] & 0xff) << 8) | (buffer[3] & 0xff);
+ return new Header(lastMetadataBlock, blockType, length);
+ }
+
+}
--- /dev/null
+/*
+ * Sonitus - MetadataBlock.java - Copyright © 2013 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sonitus.io.flac;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * A metadata block.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class MetadataBlock {
+
+ /** The header of the metadata block. */
+ private final Header header;
+
+ /** The data of the metadata block. */
+ private final Data data;
+
+ /**
+ * Creates a new metadata block.
+ *
+ * @param header
+ * The header of the metadata block
+ * @param data
+ * The data of the metadata block
+ */
+ MetadataBlock(Header header, Data data) {
+ this.header = header;
+ this.data = data;
+ }
+
+ //
+ // ACCESSORS
+ //
+
+ /**
+ * Returns the header of this metadata block.
+ *
+ * @return The header of this metadata block
+ */
+ public Header header() {
+ return header;
+ }
+
+ /**
+ * Returns the data of this metadata block.
+ *
+ * @return The data of this metadata block
+ */
+ public Data data() {
+ return data;
+ }
+
+ //
+ // STATIC METHODS
+ //
+
+ /**
+ * Parses the metadata block from the current position of the given input
+ * stream.
+ *
+ * @param inputStream
+ * The input stream to parse the metadata block from
+ * @return The parsed metadata block
+ * @throws IOException
+ * if an I/O error occurs
+ */
+ public static MetadataBlock parse(InputStream inputStream) throws IOException {
+ Header header = Header.parse(inputStream);
+ Data data = Data.parse(inputStream, header.blockType(), header.length());
+ return new MetadataBlock(header, data);
+ }
+
+}
--- /dev/null
+/*
+ * Sonitus - MetadataBlock.java - Copyright © 2013 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sonitus.io.flac;
+
+import static com.google.common.io.ByteStreams.readFully;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.List;
+
+import com.google.common.base.Optional;
+import com.google.common.base.Predicate;
+import com.google.common.collect.FluentIterable;
+import com.google.common.collect.Lists;
+
+/**
+ * Parser and container for information about a FLAC stream.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class Stream {
+
+ /** The metadata blocks of the stream. */
+ private final List<MetadataBlock> metadataBlocks = Lists.newArrayList();
+
+ /**
+ * Creates a new FLAC stream containing the given metadata blocks.
+ *
+ * @param metadataBlocks
+ * The metadata blocks in order of appearance
+ */
+ private Stream(List<MetadataBlock> metadataBlocks) {
+ this.metadataBlocks.addAll(metadataBlocks);
+ }
+
+ //
+ // ACCESSORS
+ //
+
+ /**
+ * Returns all metadata blocks of the given block type, in the order they
+ * appear in this stream.
+ *
+ * @param blockType
+ * The block type to get all metadata blocks for
+ * @return The metadata blocks of the given block type
+ */
+ public Collection<MetadataBlock> metadataBlocks(final BlockType blockType) {
+ return FluentIterable.from(metadataBlocks).filter(new Predicate<MetadataBlock>() {
+
+ @Override
+ public boolean apply(MetadataBlock metadataBlock) {
+ return metadataBlock.header().blockType() == blockType;
+ }
+ }).toList();
+ }
+
+ //
+ // STATIC METHODS
+ //
+
+ /**
+ * Parses the given input stream and returns information about the stream if it
+ * can be successfully parsed as a FLAC stream.
+ *
+ * @param inputStream
+ * The input stream containing the FLAC stream
+ * @return The parsed FLAC stream, or {@link Optional#absent()} if no FLAC
+ * stream could be found at the stream’s current position
+ * @throws IOException
+ * if an I/O error occurs
+ */
+ public static Optional<Stream> parse(InputStream inputStream) throws IOException {
+ byte[] streamTag = new byte[4];
+ readFully(inputStream, streamTag);
+ if (!Arrays.equals(streamTag, new byte[] { 'f', 'L', 'a', 'C' })) {
+ return Optional.absent();
+ }
+ List<MetadataBlock> metadataBlocks = Lists.newArrayList();
+ while (true) {
+ MetadataBlock metadataBlock = MetadataBlock.parse(inputStream);
+ metadataBlocks.add(metadataBlock);
+ if (metadataBlock.header().isLastMetadataBlock()) {
+ break;
+ }
+ }
+ return Optional.of(new Stream(metadataBlocks));
+ }
+
+}
--- /dev/null
+/*
+ * Sonitus - StreamInfo.java - Copyright © 2013 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sonitus.io.flac;
+
+/**
+ * Parser for a {@link BlockType#STREAMINFO} metadata block.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class StreamInfo extends Data {
+
+ /**
+ * Creates a new STREAMINFO block from the given buffer.
+ *
+ * @param content
+ * The contents of the metadata block
+ */
+ public StreamInfo(byte[] content) {
+ super(content);
+ }
+
+ //
+ // ACCESSORS
+ //
+
+ /**
+ * Returns the minimum block size.
+ *
+ * @return The minimum block size (in samples)
+ */
+ public int minimumBlockSize() {
+ return (int) parseBits(0, 0, 16);
+ }
+
+ /**
+ * Returns the maximum block size.
+ *
+ * @return The maximum block size (in samples)
+ */
+ public int maximumBlockSize() {
+ return (int) parseBits(2, 0, 16);
+ }
+
+ /**
+ * Returns the minimum frame size.
+ *
+ * @return The minimum frame size (in bytes)
+ */
+ public int minimumFrameSize() {
+ return (int) parseBits(4, 0, 24);
+ }
+
+ /**
+ * Returns the maximum frame size.
+ *
+ * @return The maximum frame size (in bytes)
+ */
+ public int maximumFrameSize() {
+ return (int) parseBits(7, 0, 24);
+ }
+
+ /**
+ * Returns the sample rate.
+ *
+ * @return The sample rate (in Hertz)
+ */
+ public int sampleRate() {
+ return (int) parseBits(10, 0, 20);
+ }
+
+ /**
+ * Returns the number of channels.
+ *
+ * @return The number of channels
+ */
+ public int numberOfChannels() {
+ return (int) (parseBits(12, 4, 3) + 1);
+ }
+
+ /**
+ * Returns the number of bits per sample.
+ *
+ * @return The number of bits per sample
+ */
+ public int bitsPerSample() {
+ return (int) (parseBits(12, 7, 5) + 1);
+ }
+
+ /**
+ * Returns the total number of samples.
+ *
+ * @return The total number of samples
+ */
+ public long totalSamples() {
+ return parseBits(13, 4, 36);
+ }
+
+}