SWORD25: Initial code for showing savegame thumbnails

There is currently a bug and only the thumbnail of the first save slot is
shown

3 files changed, 62 insertions, 11 deletions

diff --git a/engines/sword25/gfx/graphicengine.cpp b/engines/sword25/gfx/graphicengine.cpp
index 2772401c6a..371df7ac0f 100644
--- a/engines/sword25/gfx/graphicengine.cpp
+++ b/engines/sword25/gfx/graphicengine.cpp
@@ -266,8 +266,9 @@ Resource *GraphicEngine::loadResource(const Common::String &filename) {
 		return pResource;
 	}
 
-	// Load sprite image
-	if (filename.hasSuffix(".png") || filename.hasSuffix(".b25s")) {
+	// Load sprite image. Savegame thumbnails are also loaded here.
+	if (filename.hasSuffix(".png") || filename.hasSuffix(".b25s") ||
+		filename.hasPrefix("/saves")) {
 		bool result = false;
 		RenderedImage *pImage = new RenderedImage(filename, result);
 		if (!result) {
@@ -354,7 +355,8 @@ bool GraphicEngine::canLoadResource(const Common::String &filename) {
 		filename.hasSuffix("_ani.xml") ||
 		filename.hasSuffix("_fnt.xml") ||
 		filename.hasSuffix(".swf") ||
-		filename.hasSuffix(".b25s");
+		filename.hasSuffix(".b25s") ||
+		filename.hasPrefix("/saves");
 }
 
 void  GraphicEngine::updateLastFrameDuration() {
diff --git a/engines/sword25/kernel/persistenceservice.cpp b/engines/sword25/kernel/persistenceservice.cpp
index 8d54c24918..500703befb 100644
--- a/engines/sword25/kernel/persistenceservice.cpp
+++ b/engines/sword25/kernel/persistenceservice.cpp
@@ -134,14 +134,6 @@ struct PersistenceService::Impl {
 		// Iterate through all the saved games, and read their thumbnails.
 		for (uint i = 0; i < SLOT_COUNT; ++i) {
 			readSlotSavegameInformation(i);
-			// TODO: This function is supposed to load savegame screenshots
-			// into an appropriate array (or the header struct of each saved
-			// game). Currently, it's a stub. For each slot, we should skip
-			// the header plus gameDataLength bytes and read the screenshot
-			// data. Then, these screenshots should be used for the save list
-			// screen. The thumbnail code seems to be missing completely,
-			// though (unless I'm mistaken), so these thumbnails aren't used
-			// anywhere currently.
 		}
 	}
 
diff --git a/engines/sword25/package/packagemanager.cpp b/engines/sword25/package/packagemanager.cpp
index 7a64fe2e29..7c6343a18f 100644
--- a/engines/sword25/package/packagemanager.cpp
+++ b/engines/sword25/package/packagemanager.cpp
@@ -141,6 +141,29 @@ bool PackageManager::loadDirectoryAsPackage(const Common::String &directoryName,
 	}
 }
 
+// Duplicated from kernel/persistenceservice.cpp
+static Common::String generateSavegameFilename(uint slotID) {
+	char buffer[100];
+	// NOTE: This is hardcoded to sword25
+	snprintf(buffer, 100, "%s.%.3d", "sword25", slotID);
+	return Common::String(buffer);
+}
+
+// Duplicated from kernel/persistenceservice.cpp
+static Common::String loadString(Common::InSaveFile *in, uint maxSize = 999) {
+	Common::String result;
+
+	char ch = (char)in->readByte();
+	while (ch != '\0') {
+		result += ch;
+		if (result.size() >= maxSize)
+			break;
+		ch = (char)in->readByte();
+	}
+
+	return result;
+}
+
 byte *PackageManager::getFile(const Common::String &fileName, uint *fileSizePtr) {
 	const Common::String B25S_EXTENSION(".b25s");
 	Common::SeekableReadStream *in;
@@ -165,6 +188,40 @@ byte *PackageManager::getFile(const Common::String &fileName, uint *fileSizePtr)
 		return buffer;
 	}
 
+	if (fileName.hasPrefix("/saves")) {
+		// A savegame thumbnail
+		Common::SaveFileManager *sfm = g_system->getSavefileManager();
+		int slotNum = atoi(fileName.c_str() + fileName.size() - 3);
+		Common::InSaveFile *file = sfm->openForLoading(generateSavegameFilename(slotNum));
+
+		if (file) {
+			loadString(file);	// storedMarker
+			loadString(file);	// storedVersionID
+			loadString(file);	// gameDescription
+			int gameDataLength = atoi(loadString(file).c_str());
+			loadString(file);	// gamedataUncompressedLength
+			// Skip the savegame data
+			file->skip(gameDataLength);
+
+			int thumbnailSize = file->size() - file->pos();
+
+			if (thumbnailSize <= 0) {
+				warning("Saved game at slot %d does not contain a thumbnail", slotNum);
+				delete file;
+				return 0;
+			}
+
+			if (fileSizePtr)
+				*fileSizePtr = thumbnailSize;
+
+			byte *thumbnail = new byte[thumbnailSize];
+			file->read(thumbnail, thumbnailSize);
+			
+			delete file;
+			return thumbnail;
+		}
+	}
+
 	Common::ArchiveMemberPtr fileNode = getArchiveMember(normalizePath(fileName, _currentDirectory));
 	if (!fileNode)
 		return 0;