Merge pull request 'Refactor jef reader for .jef files' (#2) from refactor_jef into main

Reviewed-on: #2

package.json

@@ -1,7 +1,7 @@
 {
   "name": "embroidery-viewer",
   "private": true,
-  "version": "1.2.1",
+  "version": "1.2.2",
   "type": "module",
   "scripts": {
     "dev": "vite",

src/format-readers/jef.js

@@ -82,54 +82,52 @@ const colors = [
   new Color(227, 172, 129, "Bamboo"),
 ];
 
-function jefDecode(inputByte) {
-  return inputByte >= 0x80 ? -(~inputByte & 0xff) - 1 : inputByte;
+const jefDecode = (byte) => (byte >= 0x80 ? -(~byte & 0xff) - 1 : byte);
+const isSpecialStitch = (byte) => byte === 0x80;
+const isStopOrTrim = (byte) => (byte & 0x01) !== 0 || byte === 0x02 || byte === 0x04;
+const isEndOfPattern = (byte) => byte === 0x10;
+const isStop = (byte) => byte & 0x01;
+const readStitchData = (file) => ({ byte1: file.getUint8(), byte2: file.getUint8() });
+
+const addColorsToPattern = (file, pattern, colorCount) => {
+  for (let i = 0; i < colorCount; i++) {
+    pattern.addColor(colors[file.getUint32(file.tell(), true) % colors.length]);
+  }
+};
+
+const determineStitchType = (file, byte1, byte2) => {
+  if (isSpecialStitch(byte1)) {
+    if (isStopOrTrim(byte2)) {
+      return { type: isStop(byte2) ? stitchTypes.stop : stitchTypes.trim, byte1: file.getUint8(), byte2: file.getUint8() };
+    } else if (isEndOfPattern(byte2)) {
+      return { type: stitchTypes.end, byte1: 0, byte2: 0, end: true };
+    }
+  }
+  return { type: stitchTypes.normal, byte1, byte2 };
+}
+
+const processStitches = (file, pattern, stitchCount) => {
+  let stitchesProcessed = 0;
+  while (stitchesProcessed < stitchCount + 100) {
+    let { byte1, byte2 } = readStitchData(file);
+    let { type, byte1: decodedByte1, byte2: decodedByte2, end } = determineStitchType(file, byte1, byte2);
+    pattern.addStitchRel(jefDecode(decodedByte1), jefDecode(decodedByte2), type, true);
+    if (end) break;
+    stitchesProcessed++;
+  }
 }
 
 export function jefRead(file, pattern) {
   file.seek(24);
-  const numberOfColors = file.getInt32(file.tell(), true);
-  const numberOfStitches = file.getInt32(file.tell(), true);
+  const colorCount = file.getInt32(file.tell(), true);
+  const stitchCount = file.getInt32(file.tell(), true);
   file.seek(file.tell() + 84);
 
-  for (let i = 0; i < numberOfColors; i += 1) {
-    pattern.addColor(colors[file.getUint32(file.tell(), true) % 78]);
-  }
-  for (let i = 0; i < 6 - numberOfColors; i += 1) {
-    file.getUint32();
-  }
+  addColorsToPattern(file, pattern, colorCount);
+  file.seek(file.tell() + (6 - colorCount) * 4);
 
-  let flags,
-    b0,
-    b1,
-    dx,
-    dy,
-    stitchCount = 0;
-  while (stitchCount < numberOfStitches + 100) {
-    flags = stitchTypes.normal;
-    b0 = file.getUint8();
-    b1 = file.getUint8();
-
-    if (b0 === 0x80) {
-      if (b1 & 0x01) {
-        b0 = file.getUint8();
-        b1 = file.getUint8();
-        flags = stitchTypes.stop;
-      } else if (b1 === 0x02 || b1 === 0x04) {
-        b0 = file.getUint8();
-        b1 = file.getUint8();
-        flags = stitchTypes.trim;
-      } else if (b1 === 0x10) {
-        pattern.addStitchRel(0, 0, stitchTypes.end, true);
-        break;
-      }
-    }
-    dx = jefDecode(b0);
-    dy = jefDecode(b1);
-    pattern.addStitchRel(dx, dy, flags, true);
-    stitchCount += 1;
-  }
+  processStitches(file, pattern, stitchCount);
   pattern.invertPatternVertical();
 }
 
-export const jefColors = colors;
+export const jefColors = colors;