Cleaned up the frame.ts by splitting payload parsing to subpackages

src/payload.item.ts

@@ -0,0 +1,149 @@
+import { FieldType, type Segment } from "@hamradio/packet";
+
+import { DO_NOT_ARCHIVE_MARKER, DataType, type IPosition, type ItemPayload, type Payload } from "./frame.types";
+import { attachExtras, decodeCommentExtras } from "./payload.extras";
+import { isCompressedPosition, parseCompressedPosition, parseUncompressedPosition } from "./payload.position";
+import Timestamp from "./timestamp";
+
+export const decodeItemPayload = (
+  raw: string,
+  withStructure: boolean = false
+): {
+  payload: Payload | null;
+  segment?: Segment[];
+} => {
+  // Item format is similar to Object but name may be 3-9 chars (stored in a 9-char field)
+  // Example: )NNN... where ) is data type, next 9 chars are name, then state char, then timestamp, then position
+  if (raw.length < 12) return { payload: null }; // minimal: 1 + 3 + 1 + 7
+
+  let offset = 1; // skip data type identifier ')'
+  const segment: Segment[] = withStructure ? [] : [];
+
+  // Read 9-char name field (pad/truncate as present)
+  const rawName = raw.substring(offset, offset + 9);
+  const name = rawName.trimEnd();
+  if (withStructure) {
+    segment.push({
+      name: "item name",
+      data: new TextEncoder().encode(rawName).buffer,
+      isString: true,
+      fields: [{ type: FieldType.STRING, name: "name", length: 9 }]
+    });
+  }
+  offset += 9;
+
+  // State character: '*' = alive, '_' = killed
+  const stateChar = raw.charAt(offset);
+  if (stateChar !== "*" && stateChar !== "_") {
+    return { payload: null };
+  }
+  const alive = stateChar === "*";
+  if (withStructure) {
+    segment.push({
+      name: "item state",
+      data: new TextEncoder().encode(stateChar).buffer,
+      isString: true,
+      fields: [
+        {
+          type: FieldType.CHAR,
+          name: "State (* alive, _ killed)",
+          length: 1
+        }
+      ]
+    });
+  }
+  offset += 1;
+
+  // Timestamp (7 chars)
+  const timeStr = raw.substring(offset, offset + 7);
+  const { timestamp, segment: timestampSection } = Timestamp.fromString(timeStr.substring(offset), withStructure);
+  if (!timestamp) return { payload: null };
+  if (timestampSection) segment.push(timestampSection);
+  offset += 7;
+
+  const isCompressed = isCompressedPosition(raw.substring(offset));
+
+  // eslint-disable-next-line no-useless-assignment
+  let position: IPosition | null = null;
+  // eslint-disable-next-line no-useless-assignment
+  let consumed = 0;
+
+  if (isCompressed) {
+    const { position: compressed, segment: compressedSection } = parseCompressedPosition(
+      raw.substring(offset),
+      withStructure
+    );
+    if (!compressed) return { payload: null };
+
+    position = {
+      latitude: compressed.latitude,
+      longitude: compressed.longitude,
+      symbol: compressed.symbol,
+      altitude: compressed.altitude
+    };
+    consumed = 13;
+
+    if (compressedSection) segment.push(compressedSection);
+  } else {
+    const { position: uncompressed, segment: uncompressedSection } = parseUncompressedPosition(
+      raw.substring(offset),
+      withStructure
+    );
+    if (!uncompressed) return { payload: null };
+
+    position = {
+      latitude: uncompressed.latitude,
+      longitude: uncompressed.longitude,
+      symbol: uncompressed.symbol,
+      ambiguity: uncompressed.ambiguity
+    };
+    consumed = 19;
+
+    if (uncompressedSection) segment.push(uncompressedSection);
+  }
+
+  offset += consumed;
+  const remainder = raw.substring(offset);
+  const doNotArchive = remainder.includes(DO_NOT_ARCHIVE_MARKER);
+  let comment = remainder;
+
+  const extras = decodeCommentExtras(comment, withStructure);
+  comment = extras.comment;
+
+  if (comment) {
+    position.comment = comment;
+    if (withStructure) {
+      segment.push({
+        name: "comment",
+        data: new TextEncoder().encode(remainder).buffer,
+        isString: true,
+        fields: extras.fields || []
+      });
+    }
+  } else if (withStructure && extras.fields) {
+    // No free-text comment, but extras fields exist: emit comment-only segment
+    segment.push({
+      name: "comment",
+      data: new TextEncoder().encode(remainder).buffer,
+      isString: true,
+      fields: extras.fields || []
+    });
+  }
+
+  const payload: ItemPayload = {
+    type: DataType.Item,
+    doNotArchive,
+    name,
+    alive,
+    position
+  };
+  attachExtras(payload, extras);
+
+  if (withStructure) {
+    return { payload, segment };
+  }
+
+  return { payload };
+};
+
+export default decodeItemPayload;