/**
 * 读取当前仓库生效的 git 提交者身份（user.name / user.email）。
 *
 * 提交代码前先查一遍：身份缺失时 git commit 会直接失败，与其让后台 claude
 * 跑十几分钟后才报错，不如一开始就把话说清楚。
 */

import { execFile } from 'node:child_process'

export interface GitIdentity {
  name: string
  email: string
}

export type GitIdentityKey = 'user.name' | 'user.email'

export function missingGitIdentityKeys(identity: GitIdentity): GitIdentityKey[] {
  const missing: GitIdentityKey[] = []
  if (!identity.name.trim())
    missing.push('user.name')
  if (!identity.email.trim())
    missing.push('user.email')
  return missing
}

function readGitConfig(cwd: string, key: GitIdentityKey): Promise<string> {
  return new Promise<string>((resolve) => {
    execFile(
      'git',
      ['-C', cwd, 'config', '--get', key],
      { timeout: 10_000, encoding: 'utf8' },
      (err, stdout) => {
        // 未设置该项时 git 以退出码 1 结束且无输出，视同空串即可
        resolve(err ? '' : (stdout ?? '').trim())
      },
    )
  })
}

export async function readGitIdentity(cwd: string): Promise<GitIdentity> {
  const [name, email] = await Promise.all([
    readGitConfig(cwd, 'user.name'),
    readGitConfig(cwd, 'user.email'),
  ])
  return { name, email }
}