Serialize embedded schematic image storage

lib/serialization/serialize-altium-binary-documents.ts

@@ -1,2 +1,6 @@
 export { serializeAltiumPcbDocToBinary } from "./serialize-altium-pcb-doc-to-binary"
-export { serializeAltiumSchDocToBinary } from "./serialize-altium-sch-doc-to-binary"
+export {
+  type AltiumSchematicEmbeddedImageInput,
+  type SerializeAltiumSchDocToBinaryOptions,
+  serializeAltiumSchDocToBinary,
+} from "./serialize-altium-sch-doc-to-binary"

lib/serialization/serialize-altium-sch-doc-to-binary.ts

@@ -1,4 +1,5 @@
 import type { AltiumSchDoc } from "../altium-sch-doc"
+import { encodeAltiumText } from "../parser/decode-altium-text"
 import {
   addAltiumCompoundStream,
   concatAltiumBinaryBytes,
@@ -11,9 +12,19 @@ import {
   toAltiumBinaryRecordBytes,
 } from "./altium-binary-record-encoding"
 
+export type AltiumSchematicEmbeddedImageInput = {
+  compressedBytes: Uint8Array
+  name: string
+}
+
+export type SerializeAltiumSchDocToBinaryOptions = {
+  embeddedImages?: readonly AltiumSchematicEmbeddedImageInput[]
+}
+
 /** Encodes an ASCII schematic into Altium's native OLE/CFB SchDoc container. */
 export function serializeAltiumSchDocToBinary(
   document: string | AltiumSchDoc,
+  options: SerializeAltiumSchDocToBinaryOptions = {},
 ): Uint8Array {
   const asciiDocument = getAsciiAltiumSource(document)
   const recordSources = asciiDocument
@@ -41,9 +52,7 @@ export function serializeAltiumSchDocToBinary(
   })
   addAltiumCompoundStream({
     compoundFile,
-    content: toLengthPrefixedTextBlock(
-      toAltiumBinaryRecordBytes("|HEADER=Icon storage"),
-    ),
+    content: serializeSchematicImageStorage(options.embeddedImages ?? []),
     path: "/Storage",
   })
   addAltiumCompoundStream({
@@ -56,6 +65,40 @@ export function serializeAltiumSchDocToBinary(
   return writeAltiumCompoundFile(compoundFile)
 }
 
+function serializeSchematicImageStorage(
+  embeddedImages: readonly AltiumSchematicEmbeddedImageInput[],
+): Uint8Array {
+  const header = toLengthPrefixedTextBlock(
+    toAltiumBinaryRecordBytes("|HEADER=Icon storage"),
+  )
+  const entries = embeddedImages.map(({ compressedBytes, name }) => {
+    const nameBytes = encodeAltiumText(name, "windows-1252")
+    if (nameBytes.byteLength === 0 || nameBytes.byteLength > 255) {
+      throw new RangeError(
+        "Embedded schematic image names must be 1 to 255 Windows-1252 bytes",
+      )
+    }
+    if (compressedBytes.byteLength === 0) {
+      throw new RangeError(
+        "Embedded schematic image compressed bytes must not be empty",
+      )
+    }
+    const entry = concatAltiumBinaryBytes([
+      Uint8Array.of(0xd0, nameBytes.byteLength),
+      nameBytes,
+      uint32AltiumBytes(compressedBytes.byteLength),
+      compressedBytes,
+    ])
+    if (entry.byteLength > 0x00ff_ffff) {
+      throw new RangeError(
+        "Embedded schematic image storage entries must fit in 24 bits",
+      )
+    }
+    return concatAltiumBinaryBytes([uint32AltiumBytes(entry.byteLength), entry])
+  })
+  return concatAltiumBinaryBytes([header, ...entries])
+}
+
 function toLengthPrefixedTextBlock(recordBytes: Uint8Array): Uint8Array {
   return concatAltiumBinaryBytes([
     uint32AltiumBytes(recordBytes.byteLength),

tests/binary-schematic-document-creation.test.ts

@@ -16,3 +16,24 @@ test("creates native binary schematic documents", () => {
   expect(document.components).toHaveLength(1)
   expect(document.components[0]?.getDecoded("COMMENT")).toBe("10k Ω")
 })
+
+test("creates native schematic image storage", () => {
+  const compressedBytes = Uint8Array.of(0x78, 0x9c, 0x01, 0x02, 0x03)
+  const bytes = serializeAltiumSchDocToBinary(
+    [
+      "|HEADER=Protel for Windows - Schematic Capture Ascii File Version 5.0|WEIGHT=2",
+      "|RECORD=31|CUSTOMX=1000|CUSTOMY=800|USECUSTOMSHEET=T",
+      "|RECORD=30|OWNERINDEX=-1|FILENAME=logo.png|LOCATION.X=10|LOCATION.Y=10|CORNER.X=20|CORNER.Y=20",
+    ].join("\r\n"),
+    {
+      embeddedImages: [{ compressedBytes, name: "logo.png" }],
+    },
+  )
+  const document = parseAltiumSchDoc(bytes)
+
+  expect(document.embeddedImages).toHaveLength(1)
+  expect(document.embeddedImages[0]?.name).toBe("logo.png")
+  expect(document.embeddedImages[0]?.getCompressedBytes()).toEqual(
+    compressedBytes,
+  )
+})