From 77a41d47c3265c96042e19b65611a8340c130374 Mon Sep 17 00:00:00 2001
From: n loewen <nick@nloewen.com>
Date: Sat, 2 Sep 2023 20:55:45 -0700
Subject: [PATCH] assembler - Change to a tidier approach, made possible by new
 Opter library

---
 src/assembler.js | 55 +++++++++++++++++++++++++++---------------------
 1 file changed, 31 insertions(+), 24 deletions(-)

diff --git a/src/assembler.js b/src/assembler.js
index 68b54aa..ba9bf01 100755
--- a/src/assembler.js
+++ b/src/assembler.js
@@ -175,6 +175,7 @@ function handleConstantDefinitions(op, arg, IP, constants) {
  * @param {string} source - Assembly source to decode
  * @return {{ sourceInfo: Object, machineCode: Array }};
  **/
+// TODO rename?
 function decodeInstructions(source) {
   dbg.nit('Pre-parsing...');
   let lines = preparseSourceCode(source);
@@ -212,8 +213,8 @@ function decodeInstructions(source) {
   let labels = {};
   let constants = {};
 
-
   // Decode line by line...
+
   for (let i = 0; i < lines.length; i++) {
     let line = lines[i];
     // dbg(2, `line info:`);
@@ -239,7 +240,6 @@ function decodeInstructions(source) {
         }
       }
 
-
       // *** Decode special operations ***
 
       // Opcodes - Handle label definitions
@@ -350,7 +350,6 @@ function decodeInstructions(source) {
         machine: [decodedOp, decodedArg]
       };
 
-
       dbg.i();
       dbg.i(`Line ${line.number}: ${line.source}`);
       if (line.argument) {
@@ -409,27 +408,37 @@ function stripWhitespaceFromEnds(line) {
  * If 'includeMetadata' is true, a JSON object containing
  * both machine code and metadata is written to the output file.
  * Otherwise, a string of decimal numbers is written.
- * @arg {string} sourceCode - Source code to assemble
- * @arg {string} [outputFile] -  Output file for machine code (and optional metadata)
- * @arg {boolean} [includeMetadata=false] - Include metadata when writing output to a file? (for use when debugging using the simulator)
+ * @arg {string} inputFilename File containing code to assemble
+ * @arg {boolean} outputToFile If false, output is on stdout
+ * @arg {boolean} includeMetadata Include metadata when writing output to a file? (for use when debugging using the simulator)
+ * @arg {string} [outputFilename] Output file for machine code (and optional metadata)
  **/
-function assemble(sourceCode, outputFile='out.txt', includeMetadata=false) {
+function assemble(inputFilename, outputToFile, includeMetadata, outputFilename=null) {
+  const sourceCode = fs.readFileSync(inputFilename, 'utf8');
   const out = decodeInstructions(sourceCode);
 
-  if (returnOnStdout) {
+  if (includeMetadata) {
     const debugJSON = JSON.stringify(out);
-    console.log(debugJSON);
-  } else if (!includeMetadata) {
-    const asciiMachineCode = out.machineCode.toString().replace(/,/g, ' ');
-    fs.writeFileSync(outputFile, asciiMachineCode);
+    if (outputToFile) {
+      fs.writeFileSync(outputFilename, debugJSON);
+    } else {
+      console.log(debugJSON);
+    }
   } else {
-    const debugJSON = JSON.stringify(out);
-    fs.writeFileSync(outputFile, debugJSON);
+    const asciiMachineCode = out.machineCode.toString().replace(/,/g, ' ');
+    if (outputToFile) {
+      fs.writeFileSync(outputFilename, asciiMachineCode);
+    } else {
+      console.log(asciiMachineCode);
+    }
   }
 }
 
 /** MAIN **/
 
+// Initialize debugger...
+const dbg = new DBG('nitpick');
+
 // Handle command-line options...
 const opts = new Opter(process.argv);
 opts.synonymize('-d', '--debug');
@@ -438,16 +447,14 @@ opts.requireOptionArgument('-i', 1, 1, 'Input file required (-i prog.asm)');
 opts.requireOptionArgument('-o', 1, 1, 'Missing output file name (-o prog.asm)');
 
 const inputFilename = opts.opts.i[0];
-const inputFile_str = fs.readFileSync(inputFilename, 'utf8');
-
-let outputFileProvided = opts.contains('-o');
-let returnOnStdout = !outputFileProvided;
-let outputFilename = outputFileProvided ? opts.opts.o[0] : null;
-
+const outputToFile = opts.contains('-o');
 let outputWithMetadata = opts.contains('--debug');
 
-// Initialize debugger...
-const dbg = returnOnStdout ? new DBG('none') : new DBG('nitpick');
-
 // Assemble...!
-assemble(inputFile_str, outputFilename, outputWithMetadata);
+if (outputToFile) {
+  const outputFilename = opts.opts.o[0];
+  assemble(inputFilename, outputToFile, outputWithMetadata, outputFilename);
+} else {
+  dbg.setLevel('none');
+  assemble(inputFilename, outputToFile, outputWithMetadata);
+}