import { describe, expect, it, vi } from 'vitest'
import {
  defaultConcurrency,
  formatGateResultReason,
  gatesForMode,
  runGate,
  runGates,
  type Gate,
  type GateResult,
} from './run-gates.ts'

function gate(id: string, options: Partial<Gate> = {}): Gate {
  return {
    id,
    label: id,
    displayCommand: `run ${id}`,
    command: process.execPath,
    args: ['-e', ''],
    ...options,
  }
}

function resultFor(subject: Gate, status: GateResult['status'] = 'passed'): GateResult {
  return {
    gate: subject,
    status,
    durationMs: 10,
    output: [],
    exitCode: status === 'passed' ? 0 : 1,
    signalCode: null,
  }
}

function withPnpmEntrypoint<T>(action: () => T): T {
  const previous = process.env.npm_execpath
  process.env.npm_execpath = '/private/pnpm.cjs'
  try {
    return action()
  } finally {
    if (previous === undefined) Reflect.deleteProperty(process.env, 'npm_execpath')
    else process.env.npm_execpath = previous
  }
}

describe('gate graph validation', () => {
  it.each([
    'ci-primary',
    'ci-static',
    'ci-lint',
    'ci-coverage',
    'ci-snapshot',
    'ci-artifacts',
    'ci-consumers',
    'ci-windows-blocking',
    'ci-windows-complete',
    'ci-windows-observational',
    'node-compat',
    'check-all',
    'doc-sync',
  ] as const)('constructs and executes preflight for a valid non-empty %s graph', async (mode) => {
    const subject = withPnpmEntrypoint(() => gatesForMode(mode))
    const execute = vi.fn(async (item: Gate) => resultFor(item))

    await expect(runGates(subject, subject.length, execute)).resolves.toHaveLength(subject.length)
  })

  it.each([
    ['empty', [], /gate graph has no gates/],
    ['duplicate ids', [gate('same'), gate('same')], /duplicate gate id "same"/],
    ['unknown dependencies', [gate('subject', { needs: ['missing'] })], /depends on unknown gate "missing"/],
    ['cycles', [gate('first', { needs: ['second'] }), gate('second', { needs: ['first'] })], /dependency cycle: first -> second -> first/],
  ] as const)('rejects %s before starting a child', async (_label, invalid, message) => {
    const execute = vi.fn(async (subject: Gate) => resultFor(subject))

    await expect(runGates([...invalid], 1, execute)).rejects.toThrow(message)
    expect(execute).not.toHaveBeenCalled()
  })

  it('rejects an invalid worker count before starting a child', async () => {
    const execute = vi.fn(async (subject: Gate) => resultFor(subject))

    await expect(runGates([gate('subject')], 0, execute)).rejects.toThrow('max concurrency must be a positive integer')
    expect(execute).not.toHaveBeenCalled()
  })

  it('skips dependents after their prerequisite fails', async () => {
    const dependent = gate('dependent', { needs: ['root'] })
    const root = gate('root')
    const execute = vi.fn(async (subject: Gate) => resultFor(subject, 'failed'))

    const results = await runGates([dependent, root], 1, execute)

    expect(execute).toHaveBeenCalledOnce()
    expect(execute).toHaveBeenCalledWith(root)
    expect(results[0]).toMatchObject({ gate: dependent, status: 'skipped', error: 'dependency failed or skipped: root' })
  })
})

describe('Node 24 consumer graph', () => {
  it('owns the seven-command pool and orders restored-artifact consumers', () => {
    const subject = withPnpmEntrypoint(() => gatesForMode('ci-consumers'))

    expect(defaultConcurrency('ci-consumers', subject.length, 4)).toEqual({
      workers: 7,
      source: 'ci-consumers gate count',
    })
    expect(subject.map(item => item.id)).toEqual([
      'lint-and-duplication',
      'node-compat',
      'snapshot',
      'publint',
      'node-next-types',
      'built-package-invariants',
      'built-bin-smoke',
    ])
    expect(subject.find(item => item.id === 'publint')?.needs).toBeUndefined()
    expect(subject.find(item => item.id === 'built-package-invariants')?.needs).toEqual(['publint'])
    expect(subject.find(item => item.id === 'lint-and-duplication')?.needs).toEqual(['built-package-invariants'])
    for (const id of ['snapshot', 'node-next-types', 'built-bin-smoke']) {
      expect(subject.find(item => item.id === id)?.needs).toEqual(['built-package-invariants'])
    }
    expect(subject.find(item => item.id === 'snapshot')?.env).toEqual({ DSH_EXAMPLE_MODE: 'lib' })
  })
})

describe('gate process outcomes', () => {
  it.skipIf(process.platform === 'win32')('reports signal termination independently from exit status', async () => {
    const result = await runGate(gate('terminated', {
      args: ['-e', "process.kill(process.pid, 'SIGTERM')"],
    }))

    expect(result.status).toBe('failed')
    expect(result.exitCode).toBeNull()
    expect(result.signalCode).toBe('SIGTERM')
    expect(formatGateResultReason(result)).toBe('signal SIGTERM')
  })
})