fix: use proper phrase decompress algorithm

[deploy]

src/lib/assets/keymaps/action-codes.yml

@@ -1,5 +1,5 @@
 name: Action Codes
-description: 10-bit action codes 0x00-0x1F
+description: Invalid action codes
 actions:
   0x00:
     id: "0x00"

src/lib/serial/chord.spec.ts

@@ -28,11 +28,11 @@ describe("chords", function () {
 
   describe("phrase", function () {
     it("should stringify", function () {
-      expect(stringifyPhrase([0x01, 0x68, 0x72, 0xd4, 0x65])).toEqual("016872D465")
+      expect(stringifyPhrase([0x20, 0x68, 0x72, 0xd4, 0x65, 0x1fff])).toEqual("206872D4651FFF")
     })
 
     it("should parse", function () {
-      expect(parsePhrase("016872D465")).toEqual([0x01, 0x68, 0x72, 0xd4, 0x65])
+      expect(parsePhrase("206872D4651FFF")).toEqual([0x20, 0x68, 0x72, 0xd4, 0x65, 0x1fff])
     })
   })
 

src/lib/serial/chord.ts

@@ -1,16 +1,20 @@
+import {compressActions, decompressActions} from "../serialization/actions"
+
 export interface Chord {
   actions: number[]
   phrase: number[]
 }
 
 export function parsePhrase(phrase: string): number[] {
-  return Array.from({length: phrase.length / 2}).map((_, i) =>
-    Number.parseInt(phrase.slice(i * 2, i * 2 + 2), 16),
+  return decompressActions(
+    Uint8Array.from({length: phrase.length / 2}).map((_, i) =>
+      Number.parseInt(phrase.slice(i * 2, i * 2 + 2), 16),
+    ),
   )
 }
 
 export function stringifyPhrase(phrase: number[]): string {
-  return phrase
+  return [...compressActions(phrase)]
     .map(it => it.toString(16).padStart(2, "0"))
     .join("")
     .toUpperCase()

src/lib/serialization/actions.spec.ts

@@ -2,27 +2,11 @@ import {describe, it, expect} from "vitest"
 import {compressActions, decompressActions} from "./actions"
 
 describe("layout", function () {
-  const actions = [1, 5, 2, 1023, 42, 2, 4, 78]
+  const actions = [1023, 255, 256, 42, 32, 532, 8000]
 
   describe("compression", function () {
     it("should compress back and forth arrays divisible by 4", function () {
       expect(decompressActions(compressActions(actions))).toEqual(actions)
     })
-
-    it("should compress back and forth arrays divisible not divisible by 4", function () {
-      expect(decompressActions(compressActions([...actions, 1023, 512, 123]))).toEqual([
-        ...actions,
-        1023,
-        512,
-        123,
-      ])
-      expect(decompressActions(compressActions([...actions, 1023, 512]))).toEqual([...actions, 1023, 512])
-      expect(decompressActions(compressActions([...actions, 1023]))).toEqual([...actions, 1023])
-    })
-
-    it("should compress alternating 0/1023", function () {
-      const array = Array.from({length: 128}).map((_, i) => (i % 2 === 0 ? 0 : 1023))
-      expect(decompressActions(compressActions(array))).toEqual(array)
-    })
   })
 })

src/lib/serialization/actions.ts

@@ -1,23 +1,18 @@
 /**
- * Compresses an action list into a Uint8Array of 10-bit integers, supporting values of up to 1023
+ * Compresses an action list into a Uint8Array of variable-length 8/13-bit integers.
+ *
+ * Action codes <32 are invalid.
  */
 export function compressActions(actions: number[]): Uint8Array {
-  const overflow = actions.length % 4
-  const array = new Uint8Array(
-    Math.ceil((actions.length - overflow) * 1.25 + (overflow === 0 ? 0 : overflow + 1)),
-  )
-  let arrayOffset = 0
-  for (let i = 0; i < actions.length; i += 4) {
-    let final = 0
-    for (let j = 0; j < 4 && i + j < actions.length; j++) {
-      const action = actions[i + j]
-      array[arrayOffset++] = (action >>> 2) & 0xff
-      final |= (action & 0x03) << (j * 2)
+  const buffer = new Uint8Array(actions.length * 2)
+  let i = 0
+  for (const action of actions) {
+    if (action > 0xff) {
+      buffer[i++] = action >>> 8
     }
-    array[arrayOffset++] = final
+    buffer[i++] = action & 0xff
   }
-  console.assert(arrayOffset === array.length)
-  return array
+  return buffer.slice(0, i)
 }
 
 /**
@@ -27,12 +22,12 @@ export function compressActions(actions: number[]): Uint8Array {
  */
 export function decompressActions(raw: Uint8Array): number[] {
   const actions: number[] = []
-  for (let i = 0; i < raw.length + 4; i += 5) {
-    const overflow = raw[Math.min(i + 4, raw.length - 1)]
-
-    for (let j = 0; j < 4 && i + j < raw.length - 1; j++) {
-      actions.push((raw[i + j] << 2) | ((overflow >>> (j * 2)) & 0x3))
+  for (let i = 0; i < raw.length; i++) {
+    let action = raw[i]
+    if (action < 32) {
+      action = (action << 8) | raw[++i]
     }
+    actions.push(action)
   }
   return actions
 }

src/routes/config/+layout.svelte

@@ -2,7 +2,7 @@
   import {page} from "$app/stores"
   import LL from "../../i18n/i18n-svelte"
 
-  const paths = [
+  $: paths = [
     {href: "/config/chords/", title: $LL.configure.chords.TITLE(), icon: "piano"},
     {href: "/config/layout/", title: $LL.configure.layout.TITLE(), icon: "keyboard"},
     {href: "/config/settings/", title: $LL.configure.settings.TITLE(), icon: "settings"},