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Merged
Frotty merged 4 commits into from
Aug 25, 2026
Merged

Handle MPQ maps without HM3W headers #1258

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73c59e4
Handle MPQ maps without HM3W headers
Frotty Aug 25, 2026
d54d514
Preserve W3I player count in synthesized headers
Frotty Aug 25, 2026
659e909
Preserve W3I map name in synthesized headers
Frotty Aug 25, 2026
7c10423
Preserve W3I flags in synthesized headers
Frotty Aug 25, 2026
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44 changes: 37 additions & 7 deletions de.peeeq.wurstscript/src/main/java/de/peeeq/wurstio/languageserver/ProjectConfigBuilder.java
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Original file line number Diff line number Diff line change
Expand Up @@ -107,7 +107,7 @@ public static MapRequest.CompilationResult apply(WurstProjectConfigData projectC
w3I.write(result.w3i);

// Apply map header (this is cheap, so we always do it)
applyMapHeader(projectConfig, targetMap);
applyMapHeader(projectConfig, targetMap, w3I.getPlayers().size(), w3I.getMapName(), w3I.getFlags().toInt());

// Update the manifest with new config hash (must open writable to insert)
try (MpqEditor mpq = MpqEditorFactory.getEditor(Optional.of(targetMap), false)) {
Expand Down Expand Up @@ -356,20 +356,50 @@ private static void setVolatilePlayerConfig(WurstProjectBuildPlayer wplayer, W3I
}
}

private static void applyMapHeader(WurstProjectConfigData projectConfig, File targetMap) throws IOException {
private static void applyMapHeader(WurstProjectConfigData projectConfig, File targetMap,
int existingPlayerCount, String existingMapName,
int existingMapFlags) throws IOException {
boolean shouldWrite = false;
MapHeader mapHeader = MapHeader.ofFile(targetMap);
if (!projectConfig.buildMapData().players().isEmpty()) {
mapHeader.setMaxPlayersCount(projectConfig.buildMapData().players().size());
WurstProjectBuildMapData buildMapData = projectConfig.buildMapData();
if (buildMapData.players().isEmpty() && StringUtils.isBlank(buildMapData.name())) {
return;
}

// A Warcraft III map may omit the optional 512-byte HM3W prefix and start
// directly with its MPQ archive. MapHeader.ofFile only reads the prefix,
// so use a new header in that case; writeToMapFile will insert it before
// the archive.
boolean hasNoMapHeader = startsWithMpqArchive(targetMap);
MapHeader mapHeader = hasNoMapHeader
? new MapHeader()

@chatgpt-codex-connector chatgpt-codex-connector Bot Aug 25, 2026

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P2 Badge Preserve the player count in a synthesized header

When a headerless map configures only buildMapData.name() and relies on the existing war3map.w3i player definitions, this constructs a header whose maximum-player count remains the MapHeader default of zero (the new test explicitly confirms that value). The inserted HM3W header consequently advertises a zero-player map instead of preserving its existing capacity; populate the synthesized header from the already-extracted W3I metadata before writing it.

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@Frotty Frotty Aug 25, 2026

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Fixed in d54d514. Header synthesis now receives the existing W3I player count and preserves it when only map name configuration changes; the regression test asserts maxPlayersCount=3.

@chatgpt-codex-connector chatgpt-codex-connector Bot Aug 25, 2026

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P2 Badge Preserve the map name in synthesized headers

When a headerless map configures buildMapData.players() but leaves buildMapData.name() blank, this creates a MapHeader with its default map-name field and writes it in front of the archive. The resulting HM3W header therefore no longer advertises the existing name stored in war3map.w3i; pass the W3I map name into this method and populate it when synthesizing the header, analogous to the preserved player count.

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@Frotty Frotty Aug 25, 2026

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Fixed in 659e909. Header synthesis now receives the existing W3I map name and preserves it when player configuration changes without an explicit map name; the regression test covers that case.

: MapHeader.ofFile(targetMap);
Comment on lines +373 to +375

@chatgpt-codex-connector chatgpt-codex-connector Bot Aug 25, 2026

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P2 Badge Preserve W3I flags in synthesized headers

For a headerless MPQ whose W3I has nonzero map flags, such as fixed/custom forces or minimap settings, new MapHeader() leaves the header flags at their default while only the map name and player count are restored before writing. The synthesized HM3W metadata therefore disagrees with war3map.w3i, so clients that inspect the header can treat those flags as unset; pass the existing W3I flags into this path and copy them into the new header.

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@Frotty Frotty Aug 25, 2026

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Fixed in 7c10423. Header synthesis now copies the existing W3I flags via getFlags().toInt(), with regression coverage asserting the flags survive insertion.

if (!buildMapData.players().isEmpty()) {
mapHeader.setMaxPlayersCount(buildMapData.players().size());
shouldWrite = true;
} else if (hasNoMapHeader) {
mapHeader.setMaxPlayersCount(existingPlayerCount);
}
if (hasNoMapHeader && StringUtils.isBlank(buildMapData.name())) {
mapHeader.setMapName(existingMapName);
}
if (StringUtils.isNotBlank(projectConfig.buildMapData().name())) {
mapHeader.setMapName(projectConfig.buildMapData().name());
if (hasNoMapHeader) {
mapHeader.setFlags(existingMapFlags);
}
if (StringUtils.isNotBlank(buildMapData.name())) {
mapHeader.setMapName(buildMapData.name());
shouldWrite = true;
}
if (shouldWrite) {
WLogger.info("Applying map header");
mapHeader.writeToMapFile(targetMap);
}
}

private static boolean startsWithMpqArchive(File targetMap) throws IOException {
try (InputStream input = new FileInputStream(targetMap)) {
byte[] startToken = input.readNBytes(4);
return startToken.length == 4
&& new String(startToken, StandardCharsets.US_ASCII).startsWith("MPQ");
}
}
}
98 changes: 98 additions & 0 deletions de.peeeq.wurstscript/src/test/java/tests/wurstscript/tests/WurstBuildConfigTests.java
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Original file line number Diff line number Diff line change
@@ -1,16 +1,20 @@
package tests.wurstscript.tests;

import org.wurstscript.projectconfig.WurstProjectConfigData;
import org.wurstscript.projectconfig.WurstProjectBuildMapData;
import org.wurstscript.projectconfig.WurstProjectBuildPlayer;
import de.peeeq.wurstio.languageserver.WFile;
import de.peeeq.wurstio.languageserver.ProjectConfigBuilder;
import de.peeeq.wurstio.languageserver.WurstBuildConfig;
import de.peeeq.wurstio.languageserver.WurstCommands;
import de.peeeq.wurstio.utils.W3InstallationData;
import net.moonlightflower.wc3libs.bin.app.MapHeader;
import net.moonlightflower.wc3libs.port.GameVersion;
import org.testng.annotations.Test;

import java.io.File;
import java.lang.reflect.Method;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.List;
Expand Down Expand Up @@ -223,6 +227,100 @@ public void configInjectionPrefersPinnedPatchOverDetectedInstallVersion() throws
);
}

@Test
public void mapHeaderConfigAcceptsAnArchiveWithoutAnHm3wPrefix() throws Exception {
Path mapWithoutHeader = Files.createTempFile("wurst-map-without-header", ".w3x");
byte[] original = new byte[1024];
original[0] = 'M';
original[1] = 'P';
original[2] = 'Q';
original[3] = 0x1a;
Files.write(mapWithoutHeader, original);

Method applyMapHeader = ProjectConfigBuilder.class.getDeclaredMethod(
"applyMapHeader", WurstProjectConfigData.class, File.class, int.class, String.class, int.class
);
applyMapHeader.setAccessible(true);

applyMapHeader.invoke(
null,
new WurstProjectConfigData(
"Test",
List.of(),
new WurstProjectBuildMapData("Configured map", null, null, null, null, List.of(), List.of()),
null,
null
),
mapWithoutHeader.toFile(),
3,
"Existing map",
0x1234
);

assertEquals(Files.readAllBytes(mapWithoutHeader)[0], (byte) 'H');
assertEquals(MapHeader.ofFile(mapWithoutHeader.toFile()).getMaxPlayersCount(), 3);
assertEquals(Files.size(mapWithoutHeader), original.length + 512);
}

@Test
public void mapHeaderConfigDoesNotReadAnArchiveWhenNothingNeedsChanging() throws Exception {
Path mapWithoutHeader = Files.createTempFile("wurst-map-without-header-noop", ".w3x");
byte[] original = new byte[1024];
original[0] = 'M';
original[1] = 'P';
original[2] = 'Q';
original[3] = 0x1a;
Files.write(mapWithoutHeader, original);

Method applyMapHeader = ProjectConfigBuilder.class.getDeclaredMethod(
"applyMapHeader", WurstProjectConfigData.class, File.class, int.class, String.class, int.class
);
applyMapHeader.setAccessible(true);
applyMapHeader.invoke(null, WurstProjectConfigData.empty(), mapWithoutHeader.toFile(), 0, null, 0);

assertEquals(Files.readAllBytes(mapWithoutHeader), original);
}

@Test
public void mapHeaderConfigPreservesExistingMapNameWhenOnlyPlayersChange() throws Exception {
Path mapWithoutHeader = Files.createTempFile("wurst-map-without-header-name", ".w3x");
byte[] original = new byte[1024];
original[0] = 'M';
original[1] = 'P';
original[2] = 'Q';
original[3] = 0x1a;
Files.write(mapWithoutHeader, original);

Method applyMapHeader = ProjectConfigBuilder.class.getDeclaredMethod(
"applyMapHeader", WurstProjectConfigData.class, File.class, int.class, String.class, int.class
);
applyMapHeader.setAccessible(true);

applyMapHeader.invoke(
null,
new WurstProjectConfigData(
"Test",
List.of(),
new WurstProjectBuildMapData(
"", null, null, null, null,
List.of(new WurstProjectBuildPlayer(0, null, null, null, null)),
List.of()
),
null,
null
),
mapWithoutHeader.toFile(),
4,
"Existing map",
0x1234
);

byte[] result = Files.readAllBytes(mapWithoutHeader);
assertEquals(MapHeader.ofFile(mapWithoutHeader.toFile()).getMaxPlayersCount(), 1);
assertEquals(MapHeader.ofFile(mapWithoutHeader.toFile()).getFlags(), 0x1234);
assertTrue(new String(result, StandardCharsets.UTF_8).contains("Existing map"));
}

private static String calculateProjectConfigHash(File buildDir) throws Exception {
Method method = ProjectConfigBuilder.class.getDeclaredMethod(
"calculateProjectConfigHash",
Expand Down
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