init helder

src/main/git-service.ts

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+import { readFile } from 'node:fs/promises'
+import { join } from 'node:path'
+import { simpleGit, type SimpleGit } from 'simple-git'
+
+export type GitStatusLetter = 'A' | 'M' | 'D' | 'R' | 'U'
+
+export interface GitChange {
+  path: string
+  status: GitStatusLetter
+  staged: boolean
+  original: string
+  updated: string
+}
+
+export interface GitLoad {
+  branch: string
+  changes: GitChange[]
+}
+
+function git(root: string): SimpleGit {
+  return simpleGit({ baseDir: root, maxConcurrentProcesses: 4 })
+}
+
+/** Map a porcelain code pair to our display letter + staged flag. */
+function classify(index: string, working: string): { letter: GitStatusLetter; staged: boolean } {
+  const staged = index !== ' ' && index !== '?'
+  const code = staged ? index : working
+  let letter: GitStatusLetter
+  switch (code) {
+    case 'A': case 'C': case '?': letter = 'A'; break
+    case 'D': letter = 'D'; break
+    case 'R': letter = 'R'; break
+    case 'U': letter = 'M'; break
+    case 'M': default: letter = 'M'; break
+  }
+  return { letter, staged }
+}
+
+async function headText(g: SimpleGit, path: string): Promise<string> {
+  try {
+    return await g.show([`HEAD:${path}`])
+  } catch {
+    return ''
+  }
+}
+
+async function diskText(root: string, path: string): Promise<string> {
+  try {
+    const buf = await readFile(join(root, path))
+    // skip obvious binaries
+    for (let i = 0; i < Math.min(buf.length, 8000); i++) if (buf[i] === 0) return ''
+    return buf.toString('utf8')
+  } catch {
+    return ''
+  }
+}
+
+export async function isRepo(root: string): Promise<boolean> {
+  try {
+    return await git(root).checkIsRepo()
+  } catch {
+    return false
+  }
+}
+
+export async function load(root: string): Promise<GitLoad | null> {
+  const g = git(root)
+  if (!(await isRepo(root))) return null
+
+  const status = await g.status()
+  const branch = status.current || 'HEAD'
+
+  const changes: GitChange[] = []
+  for (const f of status.files) {
+    // simple-git uses path "from -> to" for renames; take the destination.
+    const path = f.path.includes(' -> ') ? f.path.split(' -> ').pop()! : f.path
+    const { letter, staged } = classify(f.index, f.working_dir)
+    const isNew = f.index === '?' || f.index === 'A'
+    const isDeleted = letter === 'D'
+    const original = isNew ? '' : await headText(g, path)
+    const updated = isDeleted ? '' : await diskText(root, path)
+    changes.push({ path, status: letter, staged, original, updated })
+  }
+
+  return { branch, changes }
+}
+
+export async function stage(root: string, paths: string[]): Promise<void> {
+  // `git add` stages modifications, additions AND deletions of the given paths.
+  await git(root).add(paths)
+}
+
+export async function unstage(root: string, paths: string[]): Promise<void> {
+  try {
+    await git(root).reset(['--', ...paths])
+  } catch {
+    // empty repo (no HEAD yet): fall back to removing from the index.
+    await git(root).raw(['rm', '--cached', '-r', '--', ...paths])
+  }
+}
+
+export async function commit(root: string, message: string): Promise<void> {
+  await git(root).commit(message)
+}
+
+export async function discard(root: string, paths: string[]): Promise<void> {
+  await git(root).checkout(['--', ...paths])
+}