feat: new sharing system

feat: support legacy layout import

src/lib/share/action-array.ts

@@ -0,0 +1,52 @@
+import {compressActions, decompressActions} from "$lib/serialization/actions"
+import {CHARA_FILE_TYPES} from "$lib/share/share-url"
+
+export type ActionArray = number[] | ActionArray[]
+export function serializeActionArray(array: ActionArray): Uint8Array {
+  let out = new Uint8Array(5)
+  const writer = new DataView(out.buffer)
+  writer.setUint32(0, array.length)
+
+  if (array.length === 0) {
+    return out
+  } else if (typeof array[0] === "number") {
+    writer.setUint8(4, CHARA_FILE_TYPES.indexOf("number"))
+    return concatUint8Arrays(out, compressActions(array as number[]))
+  } else if (Array.isArray(array[0])) {
+    writer.setUint8(4, CHARA_FILE_TYPES.indexOf("array"))
+    return concatUint8Arrays(out, ...(array as ActionArray[]).map(serializeActionArray))
+  } else {
+    throw new Error("Not implemented")
+  }
+}
+
+export function deserializeActionArray(raw: Uint8Array): ActionArray {
+  const reader = new DataView(raw.buffer)
+  const length = reader.getUint32(0)
+  const type = CHARA_FILE_TYPES[reader.getUint8(4)]
+
+  if (type === "number") {
+    return decompressActions(raw.slice(5, 5 + length))
+  } else if (type === "array") {
+    const innerLength = reader.getUint32(5)
+    const out = []
+    let cursor = 5
+    for (let i = 0; i < length; i++) {
+      out.push(deserializeActionArray(raw.slice(cursor, cursor + innerLength)))
+      cursor += innerLength
+    }
+    return out
+  } else {
+    throw new Error("Not implemented")
+  }
+}
+
+export function concatUint8Arrays(...arrays: Uint8Array[]): Uint8Array {
+  const out = new Uint8Array(arrays.reduce((a, b) => a + b.length, 0))
+  let offset = 0
+  for (const array of arrays) {
+    out.set(array, offset)
+    offset += array.length
+  }
+  return out
+}

src/lib/share/chara-file.ts

@@ -0,0 +1,15 @@
+export interface CharaFile<T extends string> {
+  charaVersion: 1
+  type: T
+}
+
+export interface CharaLayoutFile extends CharaFile<"layout"> {
+  device: "one" | "lite" | string
+  layout: [number[], number[], number[]]
+}
+
+export interface CharaChordFile extends CharaFile<"chords"> {
+  chords: [number[], number[]]
+}
+
+export type CharaFiles = CharaLayoutFile | CharaChordFile

src/lib/share/share-url.ts

@@ -0,0 +1,61 @@
+import type {CharaFile, CharaFiles} from "$lib/share/chara-file"
+import type {ActionArray} from "$lib/share/action-array"
+import {deserializeActionArray, serializeActionArray} from "$lib/share/action-array"
+import {fromBase64, toBase64} from "$lib/serialization/base64"
+
+type CharaLayoutOrder = {
+  [K in CharaFiles["type"]]: Array<
+    [Exclude<keyof Extract<CharaFiles, {type: K}>, keyof CharaFile<any>>, (typeof CHARA_FILE_TYPES)[number]]
+  >
+}
+
+const keys: CharaLayoutOrder = {
+  layout: [
+    ["layout", "array"],
+    ["device", "string"],
+  ],
+  chords: [["chords", "array"]],
+}
+
+export const CHARA_FILE_TYPES = ["unknown", "number", "string", "array"] as const
+
+const sep = "\n"
+
+export async function charaFileToUriComponent<T extends CharaFiles>(file: T): Promise<string> {
+  let url = `${file.type}${sep}${file.charaVersion}`
+
+  for (const [key, type] of keys[file.type]) {
+    const value = file[key as keyof T]
+    url += sep
+    if (type === "string") {
+      url += value as string
+    } else if (type === "array") {
+      const stream = new Blob([serializeActionArray(value as ActionArray)])
+        .stream()
+        .pipeThrough(new CompressionStream("deflate"))
+      url += await toBase64(await new Response(stream).blob())
+    } else {
+      throw new Error("Not implemented")
+    }
+  }
+
+  return url
+}
+
+export async function charaFileFromUriComponent<T extends CharaFiles>(uriComponent: string): Promise<T> {
+  const [fileType, version, ...values] = uriComponent.split(sep)
+  const file: any = {type: fileType, version: Number(version)}
+
+  for (const [key, type] of keys[fileType as keyof typeof keys]) {
+    const value = values.pop()!
+    if (type === "string") {
+      file[key] = value
+    } else if (type === "array") {
+      const stream = (await fromBase64(value)).stream().pipeThrough(new DecompressionStream("deflate"))
+      const actions = new Uint8Array(await new Response(stream).arrayBuffer())
+      file[key] = deserializeActionArray(actions)
+    }
+  }
+
+  return file
+}