import { describe, expect, it, vi } from 'vitest'

import { TerminalPipeline } from '../../src/utils/terminalPipeline'

describe('TerminalPipeline', () => {
  it('routes input and reports output bytes through one boundary', () => {
    const input = vi.fn()
    const write = vi.fn()
    const onOutputBytes = vi.fn()
    const scheduled: Array<() => void> = []
    const pipeline = new TerminalPipeline({
      input,
      output: {
        write,
        schedule: (callback) => {
          scheduled.push(callback)
          return scheduled.length
        },
        cancel: vi.fn(),
      },
      onOutputBytes,
    })

    pipeline.input('date\r')
    pipeline.output(Uint8Array.from([0x68, 0x69]))
    scheduled.shift()?.()

    expect(input).toHaveBeenCalledWith('date\r')
    expect(onOutputBytes).toHaveBeenCalledWith(2)
    expect(write).toHaveBeenCalledWith('hi')
  })

  it('keeps split UTF-8 output intact and catches async input failures', async () => {
    const write = vi.fn()
    const onError = vi.fn()
    const scheduled: Array<() => void> = []
    const pipeline = new TerminalPipeline({
      input: () => Promise.reject(new Error('closed')),
      output: {
        write,
        schedule: (callback) => {
          scheduled.push(callback)
          return scheduled.length
        },
        cancel: vi.fn(),
      },
      onError,
    })

    pipeline.input('x')
    pipeline.output(Uint8Array.from([0xe4, 0xb8]))
    pipeline.output(Uint8Array.from([0xad]))
    scheduled.shift()?.()
    await Promise.resolve()

    expect(write).toHaveBeenCalledWith('中')
    expect(onError).toHaveBeenCalledOnce()
  })
})