import { spawnSync } from 'node:child_process'

const isWin = process.platform === 'win32'
const windowsShell = process.env.ComSpec || process.env.COMSPEC || 'cmd.exe'

const runners = [
  {
    probe: 'pnpm',
    run(command) {
      return `pnpm ${command}`
    }
  },
  {
    probe: 'corepack',
    run(command) {
      return `corepack pnpm ${command}`
    }
  }
]

const checks = [
  {
    name: 'Format Check',
    command: 'run format:check',
    fixCommand: 'run format',
    help: 'Formatting issues were reported above and could not be auto-fixed. Review the listed files and fix them before committing again.'
  },
  {
    name: 'Lint Check',
    command: 'run lint:check',
    fixCommand: 'run lint',
    help: 'Lint errors were reported above and could not be auto-fixed. Review them and fix the affected code before committing again.'
  },
  {
    name: 'Type Check',
    command: 'run typecheck',
    help: 'Type errors were reported above. Review them and fix the affected code before committing again.'
  }
]

function spawnCommand(command, { stdio = 'inherit' } = {}) {
  if (isWin) {
    return spawnSync(windowsShell, ['/d', '/s', '/c', command], {
      cwd: process.cwd(),
      stdio
    })
  }

  return spawnSync('sh', ['-lc', command], {
    cwd: process.cwd(),
    stdio
  })
}

function commandExists(command) {
  const probe = isWin ? `where ${command}` : `command -v ${command}`
  const result = spawnCommand(probe, { stdio: 'ignore' })
  return !result.error && result.status === 0
}

function gitCommand(args, { stdio = 'inherit' } = {}) {
  return spawnSync('git', args, {
    cwd: process.cwd(),
    stdio
  })
}

function getStagedFiles() {
  const result = gitCommand(['diff', '--name-only', '--cached', '--diff-filter=ACMR', '-z'], {
    stdio: 'pipe'
  })

  if (result.error || result.status !== 0) {
    console.error('[pre-commit] Failed to read staged files for auto-fix restaging.')
    if (result.error) {
      console.error(result.error.message)
    }
    process.exit(result.status ?? 1)
  }

  return result.stdout.toString('utf8').split('\0').filter(Boolean)
}

function restageFiles(files) {
  if (files.length === 0) {
    return
  }

  const result = gitCommand(['add', '--', ...files])

  if (result.error || result.status !== 0) {
    console.error('[pre-commit] Auto-fix completed, but failed to restage fixed files.')
    if (result.error) {
      console.error(result.error.message)
    }
    process.exit(result.status ?? 1)
  }
}

function printDivider() {
  console.log('========================================')
}

const runner = runners.find(({ probe }) => commandExists(probe))

if (!runner) {
  console.error('[pre-commit] Unable to find pnpm or corepack in PATH.')
  process.exit(1)
}

printDivider()
console.log('[pre-commit] Running checks before commit')
printDivider()

for (const check of checks) {
  console.log(`\n[pre-commit] ${check.name}`)
  let result = spawnCommand(runner.run(check.command))

  if (result.error) {
    console.error(`\n[pre-commit] Failed to run "${check.command}".`)
    console.error(result.error.message)
    process.exit(1)
  }

  if (result.status !== 0 && check.fixCommand) {
    console.log(`\n[pre-commit] ${check.name} failed. Running auto-fix...`)
    const fixResult = spawnCommand(runner.run(check.fixCommand))

    if (fixResult.error) {
      console.error(`\n[pre-commit] Failed to run "${check.fixCommand}".`)
      console.error(fixResult.error.message)
      process.exit(1)
    }

    if (fixResult.status !== 0) {
      console.error(`\n[pre-commit] Auto-fix command "${check.fixCommand}" failed.`)
      console.error(`[pre-commit] ${check.help}`)
      console.error('[pre-commit] Commit aborted.')
      process.exit(fixResult.status ?? 1)
    }

    restageFiles(getStagedFiles())
    console.log(`[pre-commit] Auto-fix completed. Re-running ${check.name}.`)
    result = spawnCommand(runner.run(check.command))

    if (result.error) {
      console.error(`\n[pre-commit] Failed to run "${check.command}".`)
      console.error(result.error.message)
      process.exit(1)
    }
  }

  if (result.status !== 0) {
    console.error(`\n[pre-commit] ${check.name.toUpperCase()} FAILED`)
    console.error(`[pre-commit] ${check.help}`)
    console.error('[pre-commit] Commit aborted.')
    process.exit(result.status ?? 1)
  }

  console.log(`[pre-commit] ${check.name} passed.`)
}

console.log('\n[pre-commit] All checks passed. Proceeding with commit.')