From edbe168e4223631b144d5a503ad1db0b1d918aee Mon Sep 17 00:00:00 2001
From: James Roseborough <james.roseborough@luaj.org>
Date: Tue, 25 Sep 2007 00:32:25 +0000
Subject: [PATCH] Add Platform manager

---
 .../java/lua/addon/compile/Compiler.java      |  7 +--
 .../java/lua/addon/compile/FuncState.java     |  2 +-
 .../java/lua/addon/luacompat/LuaCompat.java   |  2 +-
 .../java/lua/addon/luacompat/Platform.java    | 58 +++++++++++++++++++
 4 files changed, 63 insertions(+), 6 deletions(-)
 create mode 100644 src/addon/java/lua/addon/luacompat/Platform.java

diff --git a/src/addon/java/lua/addon/compile/Compiler.java b/src/addon/java/lua/addon/compile/Compiler.java
index 6287f46e..920c44e5 100644
--- a/src/addon/java/lua/addon/compile/Compiler.java
+++ b/src/addon/java/lua/addon/compile/Compiler.java
@@ -2,10 +2,10 @@ package lua.addon.compile;
 
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.InputStreamReader;
 import java.io.Reader;
 import java.util.Hashtable;
 
+import lua.addon.luacompat.Platform;
 import lua.io.Proto;
 import lua.value.LString;
 
@@ -33,10 +33,9 @@ public class Compiler {
 		int c = stream.read();
 		if ( c == LUAC_BINARY_SIG )
 			return null;
-		// TODO: handle UTF-8 here!
-		InputStreamReader isr = new InputStreamReader(stream);
+		Reader r = Platform.getInstance().createReader( stream );
 		Compiler compiler = new Compiler();
-		return compiler.luaY_parser(c, isr, name);
+		return compiler.luaY_parser(c, r, name);
 	}
 
 	public int nCcalls;
diff --git a/src/addon/java/lua/addon/compile/FuncState.java b/src/addon/java/lua/addon/compile/FuncState.java
index 44fb85bb..7c7efe2f 100644
--- a/src/addon/java/lua/addon/compile/FuncState.java
+++ b/src/addon/java/lua/addon/compile/FuncState.java
@@ -818,7 +818,7 @@ public class FuncState extends LuaC {
 		case OP_MOD:
 			r = (LNumber) v2.luaBinOpUnknown(op, v1);
 			break;
-			//* TODO: replace this with something reasonable.
+			/* TODO: replace this with something reasonable.
 		case OP_POW:
 			r = new LDouble( Math.pow(v1.luaAsDouble(), v2.luaAsDouble() ) );
 			break;
diff --git a/src/addon/java/lua/addon/luacompat/LuaCompat.java b/src/addon/java/lua/addon/luacompat/LuaCompat.java
index 966e4588..ec036a4c 100644
--- a/src/addon/java/lua/addon/luacompat/LuaCompat.java
+++ b/src/addon/java/lua/addon/luacompat/LuaCompat.java
@@ -497,7 +497,7 @@ public class LuaCompat extends LFunction {
 		String script;
 		if ( ! "".equals(fileName) ) {
 			script = fileName;
-			is = vm.getClass().getResourceAsStream( "/"+script );
+			is = Platform.getInstance().openFile(fileName);
 			if ( is == null ) {
 				vm.setErrorResult( LNil.NIL, "cannot open "+fileName+": No such file or directory" );
 				return false;
diff --git a/src/addon/java/lua/addon/luacompat/Platform.java b/src/addon/java/lua/addon/luacompat/Platform.java
new file mode 100644
index 00000000..4aa89ceb
--- /dev/null
+++ b/src/addon/java/lua/addon/luacompat/Platform.java
@@ -0,0 +1,58 @@
+package lua.addon.luacompat;
+
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Reader;
+
+/**
+ * Singleton to manage platform-specific behaviors. 
+ *
+ */
+abstract public class Platform {
+	private static Platform instance;
+
+	/**
+	 * Singleton to be used for platform operations.
+	 * 
+	 * The default Platform gets files as resources, 
+	 * and converts them to characters using the default
+	 * InputStreamReader class.
+	 */
+	public static Platform getInstance() {
+		if ( instance == null ) {
+			instance = new Platform() {
+				public Reader createReader(InputStream inputStream) {
+					return new InputStreamReader(inputStream);
+				}
+				public InputStream openFile(String fileName) {
+					return getClass().getResourceAsStream("/"+fileName);
+				}
+			};
+		}
+		return instance;
+	}
+
+	/**
+	 * Set the Platform instance.
+	 * 
+	 * This may be useful to define a file search path, 
+	 * or custom character encoding conversion properties.
+	 */
+	public static void setInstance( Platform platform ) {
+		instance = platform;
+	}
+	
+	/**
+	 * Return an InputStream or null if not found for a particular file name.
+	 * @param fileName Name of the file to open
+	 * @return InputStream or null if not found.
+	 */
+	abstract public InputStream openFile( String fileName );
+	
+	/**
+	 * Create Reader from an InputStream
+	 * @param inputStream InputStream to read from
+	 * @return Reader instance to use for character input
+	 */
+	abstract public Reader createReader( InputStream inputStream );
+}