Add a builtin audio decoder to support caching audio files via the C_Resources API

Config/eslint.json

@@ -54,12 +54,14 @@
 		"C_WebView": "writable",
 		"BinaryReader": "writable",
 		"Bitmap": "writable",
+		"BuiltinAudioDecoder": "writable",
 		"Button": "writable",
 		"Canvas": "writable",
 		"Channels": "writable",
 		"CheckButton": "writable",
 		"Color": "writable",
 		"CRC32": "writable",
+		"Decoder": "writable",
 		"EditBox": "writable",
 		"Enum": "writable",
 		"FieldSet": "writable",

Core/API/WebAudio/BuiltinAudioDecoder.js

@@ -0,0 +1,12 @@
+// This doesn't do any actual decoding; it merely serves to utilize the Resource cache for audio playback
+// The audio engine supports no caching mechanism of its own, so we wrap any calls to disk and serve Resources instead
+class BuiltinAudioDecoder extends Decoder {
+	fileTypes = { mp3: true, ogg: true, wav: true };
+	// No need to do any decoding as these audio formats are supported natively
+	decode(resource) {
+		return resource;
+	}
+	getSupportedFileTypes() {
+		return this.fileTypes;
+	}
+}

Core/APIs/C_Decoding.js

@@ -24,15 +24,17 @@ const C_Decoding = {
 		return true;
 	},
 	addDecoder(decoder) {
-		const fileType = decoder.getSupportedFileType();
+		const fileTypes = decoder.getSupportedFileTypes();
 
-		if (this.registeredDecoders[fileType]) {
-			NOTICE(format("Failed to register decoder for file type %s (already registered)", fileType));
-			return;
-		}
+		for (const fileType of Object.keys(fileTypes)) {
+			if (this.registeredDecoders[fileType]) {
+				NOTICE(format("Failed to register decoder for file type %s (already registered)", fileType));
+				return;
+			}
 
-		this.registeredDecoders[fileType] = decoder;
-		DEBUG(format("Registered new decoder for file type *.%s", fileType.toUpperCase()));
+			this.registeredDecoders[fileType] = decoder;
+			DEBUG(format("Registered new decoder for file type *.%s", fileType.toUpperCase()));
+		}
 	},
 	decodeFile(filePath) {
 		const resource = C_Resources.load(filePath);

Core/Builtins/Decoder.js

@@ -0,0 +1,12 @@
+class Decoder {
+	fileTypes = {};
+	constructor(decodingFunction) {
+		this.decode = decodingFunction || this.decode; // NO-OP as a safe default
+	}
+	getSupportedFileTypes() {
+		return this.fileTypes;
+	}
+	decode(resource) {
+		return resource;
+	}
+}

Tests/API/C_WebAudio/BuiltinAudioDecoder.js

@@ -0,0 +1,27 @@
+describe("BuiltinAudioDecoder", () => {
+	const decoder = new BuiltinAudioDecoder();
+	it("should be exported into the global environment", () => {
+		assertEquals(decoder.constructor.name, "BuiltinAudioDecoder");
+	});
+
+	let exportedApiSurface = ["getSupportedFileTypes", "decode"];
+
+	exportedApiSurface.forEach((namedExport) => {
+		it("should export function " + namedExport, () => {
+			assertEquals(typeof decoder[namedExport], "function");
+		});
+	});
+
+	const supportedFormats = decoder.getSupportedFileTypes();
+	it("should indicate that MP3 files can be decoded", () => {
+		assertTrue(supportedFormats["mp3"]);
+	});
+
+	it("should indicate that OGG files can be decoded", () => {
+		assertTrue(supportedFormats["ogg"]);
+	});
+
+	it("should indicate that WAV files can be decoded", () => {
+		assertTrue(supportedFormats["wav"]);
+	});
+});

Tests/Builtins/Decoder.js

@@ -0,0 +1,16 @@
+describe("Decoder", () => {
+	const decoder = new Decoder();
+	it("should be exported into the global environment", () => {
+		assertEquals(decoder.constructor.name, "Decoder");
+	});
+
+	let exportedApiSurface = ["getSupportedFileTypes", "decode"];
+
+	exportedApiSurface.forEach((namedExport) => {
+		it("should export function " + namedExport, () => {
+			assertEquals(typeof decoder[namedExport], "function");
+		});
+	});
+
+	// Since this is just an interface that needs to be implemented, there's no implementation to test
+});

Tests/run-renderer-tests.js

@@ -1,11 +1,18 @@
 const testSuites = {
 	SharedConstants: ["SharedConstants/Aliases.js", "SharedConstants/Paths.js"],
-	Builtins: ["Builtins/Assertions.js", "Builtins/LocalCacheTests.js", "Builtins/UniqueID.js", "Builtins/Validators.js"],
+	Builtins: [
+		"Builtins/Assertions.js",
+		"Builtins/LocalCacheTests.js",
+		"Builtins/Decoder.js",
+		"Builtins/UniqueID.js",
+		"Builtins/Validators.js",
+	],
 	C_Settings: [
 		"API/C_Settings/validate.js",
 		"API/C_Settings/validateDefaultSettings.js",
 		"API/C_Settings/validateUserSettings.js",
 	],
+	C_WebAudio: ["API/C_WebAudio/BuiltinAudioDecoder.js"],
 };
 
 for (const namespace in testSuites) {

index.html

@@ -65,8 +65,6 @@
 		<!-- The core/engine must be loaded before the WebClient can be started -->
 		<script src="Core/Classes/AddOn.js"></script>
 
-		<script src="Core/Classes/Decoder.js"></script>
-
 		<script src="Core/Classes/HeightMap.js"></script>
 		<script src="Core/Classes/NavigationMap.js"></script>
 		<script src="Core/Classes/TerrainMap.js"></script>
@@ -140,6 +138,8 @@
 			StartWebClient();
 		</script>
 	</body>
+	<script src="Core/Builtins/Decoder.js"></script>
 	<script src="Core/Builtins/Validation.js"></script>
 	<script src="Core/Builtins/UniqueID.js"></script>
+	<script src="Core/API/WebAudio/BuiltinAudioDecoder.js"></script>
 </html>