import assert from 'node:assert/strict'
import { execFileSync, spawnSync } from 'node:child_process'
import { copyFileSync, mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs'
import { tmpdir } from 'node:os'
import { join } from 'node:path'
import { test } from 'node:test'

const SCRIPT = new URL('../scripts/check-sending-policy.mjs', import.meta.url)

function config(value) {
  return `export const SENDING = ${JSON.stringify(value)}\n`
}

function runGate({ main, branch, baseRef = 'main' }) {
  const dir = mkdtempSync(join(tmpdir(), 'sending-gate-'))
  const git = (...args) => execFileSync('git', args, { cwd: dir, stdio: 'pipe' })
  try {
    mkdirSync(join(dir, 'scripts'))
    mkdirSync(join(dir, 'src'))
    copyFileSync(SCRIPT, join(dir, 'scripts/check-sending-policy.mjs'))
    git('init', '-q', '-b', 'main')
    git('config', 'user.email', 'gate@example.com')
    git('config', 'user.name', 'gate')
    if (main !== undefined) writeFileSync(join(dir, 'src/config.js'), config(main))
    git('add', '.')
    git('commit', '-q', '-m', 'main')
    git('switch', '-q', '-c', 'feature')
    writeFileSync(join(dir, 'src/config.js'), config(branch))
    const result = spawnSync(process.execPath, ['scripts/check-sending-policy.mjs'], {
      cwd: dir,
      encoding: 'utf8',
      env: { ...process.env, SENDING_BASE_REF: baseRef },
    })
    return { status: result.status, output: result.stdout + result.stderr }
  } finally {
    rmSync(dir, { recursive: true, force: true })
  }
}

test('sending gate fails a branch that turns sending on while main is barred', () => {
  const { status, output } = runGate({ main: 'barred', branch: 'allowed' })
  assert.equal(status, 1, output)
  assert.match(output, /this branch turns sending on/)
})

test('sending gate fails a branch that sets allowed when main has no config', () => {
  assert.equal(runGate({ main: undefined, branch: 'allowed' }).status, 1)
})

test('sending gate passes a branch that inherits allowed from main', () => {
  const { status, output } = runGate({ main: 'allowed', branch: 'allowed' })
  assert.equal(status, 0, output)
})

test('sending gate passes barred branches, and a branch that bars sending again', () => {
  assert.equal(runGate({ main: 'barred', branch: 'barred' }).status, 0)
  assert.equal(runGate({ main: 'allowed', branch: 'barred' }).status, 0)
})

test('sending gate fails closed when it cannot read the base ref', () => {
  const { status, output } = runGate({ main: 'allowed', branch: 'allowed', baseRef: 'origin/missing' })
  assert.equal(status, 1, output)
  assert.match(output, /cannot read src\/config\.js at origin\/missing/)
})