Support converting PNG files to GZip

deft4j-cmd/src/main/java/com/github/NeRdTheNed/deft4j/cmd/ConvertZip.java → deft4j-cmd/src/main/java/com/github/NeRdTheNed/deft4j/cmd/ConvertToGZip.java

@@ -11,17 +11,19 @@
 import java.util.List;
 import java.util.concurrent.Callable;
 
+import com.github.NeRdTheNed.deft4j.container.ContainerUtil;
+import com.github.NeRdTheNed.deft4j.container.DeflateFilesContainer;
 import com.github.NeRdTheNed.deft4j.container.GZFile;
-import com.github.NeRdTheNed.deft4j.container.ZipFile;
+import com.github.NeRdTheNed.deft4j.container.ToGZipConvertible;
 
 import picocli.CommandLine;
 import picocli.CommandLine.Command;
 import picocli.CommandLine.Parameters;
 
-@Command(name = "convert-zip", description = "Converts a given zip file to GZip files")
-class ConvertZip implements Callable<Integer> {
+@Command(name = "convert-to-gzip", aliases = { "convert-png", "convert-zip" }, description = "Converts a given file to GZip files")
+class ConvertToGZip implements Callable<Integer> {
 
-    @Parameters(index = "0", description = "The input zip file")
+    @Parameters(index = "0", description = "The input file")
     private Path inputFile;
 
     @Parameters(index = "1", description = "The directory to output files to")
@@ -44,14 +46,19 @@ public Integer call() throws Exception {
 
         try
             (final InputStream is = new BufferedInputStream(Files.newInputStream(inputFile));
-                    final ZipFile zip = new ZipFile()) {
-            if (!zip.read(is)) {
+                    final DeflateFilesContainer container = ContainerUtil.getContainerForPath(inputFile)) {
+            if (!container.read(is)) {
                 System.err.println("Failed to read input file");
             }
 
             System.out.println("Read input file " + inputFile);
-            converted = zip.asGZipFiles();
-            System.out.println("Converted to GZip, writing files...");
+
+            if (container instanceof ToGZipConvertible) {
+                converted = ((ToGZipConvertible) container).asGZipFiles();
+                System.out.println("Converted to GZip, writing files...");
+            } else {
+                System.out.println("Could not convert input file " + inputFile + " to GZip");
+            }
         } catch (final IOException e) {
             System.err.println("IOException thrown when reading file " + inputFile);
             e.printStackTrace();

deft4j-cmd/src/main/java/com/github/NeRdTheNed/deft4j/cmd/Main.java

@@ -3,7 +3,7 @@
 import picocli.CommandLine;
 import picocli.CommandLine.Command;
 
-@Command(name = "deft4j", version = "deft4j v1.0.0-beta-5", subcommands = { Optimise.class, OptimiseFolder.class, ConvertZip.class })
+@Command(name = "deft4j", version = "deft4j v1.0.0-beta-5", subcommands = { Optimise.class, OptimiseFolder.class, ConvertToGZip.class })
 public class Main {
     public static void main(String[] args) {
         final int exitCode = new CommandLine(new Main()).execute(args);

deft4j-container/src/main/java/com/github/NeRdTheNed/deft4j/container/PNGFile.java

@@ -8,12 +8,13 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.zip.CRC32;
 
 import com.github.NeRdTheNed.deft4j.deflate.DeflateStream;
 import com.github.NeRdTheNed.deft4j.util.Util;
 
-public class PNGFile implements DeflateFilesContainer {
+public class PNGFile implements DeflateFilesContainer, ToGZipConvertible {
     class PNGChunk {
         final byte[] type = new byte[4];
         byte[] data;
@@ -178,6 +179,35 @@ boolean read(InputStream is) throws IOException {
     /** Cached CRC32 calculator */
     private final CRC32 crc32Calc = new CRC32();
 
+    @Override
+    public List<GZFile> asGZipFiles() throws IOException {
+        final List<GZFile> converted = new ArrayList<>();
+        final GZFile idatGZ = new GZFile();
+        idatGZ.setData(idat.deflateStream);
+        idatGZ.setFilename("IDAT");
+        converted.add(idatGZ);
+        final Map<String, Integer> seenChunks = new HashMap<>();
+
+        for (final Entry<PNGChunk, DeflateFilesContainer> entry : deflateStreamMapNonIDAT.entrySet()) {
+            final PNGChunk chunk = entry.getKey();
+            final DeflateFilesContainer container = entry.getValue();
+            final String type = chunk.type();
+            final int seen = seenChunks.merge(type, 1, Integer::sum);
+            final List<DeflateStream> streams = container.getDeflateStreams();
+            final int streamsSize = streams.size();
+
+            for (int i = 0; i < streamsSize; i++) {
+                final String name = type + "-num-" + seen + "-stream-" + i;
+                final GZFile chunkGZ = new GZFile();
+                chunkGZ.setData(streams.get(i));
+                chunkGZ.setFilename(name);
+                converted.add(chunkGZ);
+            }
+        }
+
+        return converted;
+    }
+
     private void syncStreams() throws IOException {
         // Find the first IDAT chunk, and store the index
         final PNGChunk firstIDAT = pngChunks.stream().filter(PNGChunk::isIDAT).findFirst().orElseThrow(() -> new IOException("No IDAT chunk found in PNG"));

deft4j-container/src/main/java/com/github/NeRdTheNed/deft4j/container/ToGZipConvertible.java

@@ -0,0 +1,8 @@
+package com.github.NeRdTheNed.deft4j.container;
+
+import java.io.IOException;
+import java.util.List;
+
+public interface ToGZipConvertible {
+    List<GZFile> asGZipFiles() throws IOException;
+}

deft4j-container/src/main/java/com/github/NeRdTheNed/deft4j/container/ZipFile.java

@@ -24,10 +24,11 @@
 import software.coley.lljzip.util.BufferData;
 import software.coley.lljzip.util.ByteDataUtil;
 
-public class ZipFile implements DeflateFilesContainer {
+public class ZipFile implements DeflateFilesContainer, ToGZipConvertible {
     private Map<LocalFileHeader, DeflateStream> deflateStreamMap;
     private ZipArchive archive;
 
+    @Override
     public List<GZFile> asGZipFiles() throws IOException {
         final List<GZFile> converted = new ArrayList<>();