feat: publish HoloLake model-native living system source

product-source/hololake-platform/src/utils/markdownFences.ts

@@ -0,0 +1,92 @@
+export type MarkdownFenceCharacter = '`' | '~'
+
+export interface MarkdownFence {
+  character: MarkdownFenceCharacter
+  length: number
+}
+
+export interface MarkdownFenceScanOptions {
+  closingMustEndLine?: boolean
+  maxLeadingSpaces?: number | null
+}
+
+const DEFAULT_MAX_LEADING_SPACES = 3
+
+function fencePrefixPattern(options: MarkdownFenceScanOptions): RegExp {
+  return options.maxLeadingSpaces === null
+    ? /^(\s*)(`{3,}|~{3,})/u
+    : /^( *)(`{3,}|~{3,})/u
+}
+
+function hasAllowedIndent(match: RegExpExecArray, options: MarkdownFenceScanOptions): boolean {
+  if (options.maxLeadingSpaces === null) return true
+  return (match[1]?.length ?? 0) <= (options.maxLeadingSpaces ?? DEFAULT_MAX_LEADING_SPACES)
+}
+
+function readFenceMatch(line: string, options: MarkdownFenceScanOptions): RegExpExecArray | null {
+  const match = fencePrefixPattern(options).exec(line)
+  return match && hasAllowedIndent(match, options) ? match : null
+}
+
+function fenceFromMatch(match: RegExpExecArray): MarkdownFence {
+  const fence = match[2] ?? ''
+  return {
+    character: fence.charAt(0) as MarkdownFenceCharacter,
+    length: fence.length,
+  }
+}
+
+export function readMarkdownFence(
+  line: string,
+  options: MarkdownFenceScanOptions = {},
+): MarkdownFence | null {
+  const match = readFenceMatch(line, options)
+  return match ? fenceFromMatch(match) : null
+}
+
+function closingTailIsAllowed(
+  line: string,
+  match: RegExpExecArray,
+  options: MarkdownFenceScanOptions,
+): boolean {
+  if (options.closingMustEndLine === false) return true
+  return /^[ \t]*$/u.test(line.slice(match[0].length))
+}
+
+function isClosingMarkdownFence(
+  line: string,
+  opening: MarkdownFence,
+  options: MarkdownFenceScanOptions,
+): boolean {
+  const match = readFenceMatch(line, options)
+  if (!match) return false
+
+  const closing = fenceFromMatch(match)
+  return closing.character === opening.character
+    && closing.length >= opening.length
+    && closingTailIsAllowed(line, match, options)
+}
+
+export function advanceMarkdownFence(
+  line: string,
+  current: MarkdownFence | null,
+  options: MarkdownFenceScanOptions = {},
+): MarkdownFence | null {
+  if (current) {
+    return isClosingMarkdownFence(line, current, options) ? null : current
+  }
+  return readMarkdownFence(line, options)
+}
+
+export function isInsideMarkdownFence(
+  markdownBeforeCursor: string,
+  options: MarkdownFenceScanOptions = {},
+): boolean {
+  let fence: MarkdownFence | null = null
+
+  for (const line of markdownBeforeCursor.split(/\r?\n/u)) {
+    fence = advanceMarkdownFence(line, fence, options)
+  }
+
+  return fence !== null
+}