const { test } = require('node:test')
const assert = require('node:assert/strict')
const fs = require('node:fs')
const vm = require('node:vm')
const ts = require('typescript')
const React = require('react')

function harness() {
  let layoutEffects = []
  let effects = []
  let resizeCallback
  let disconnected = false
  const states = []
  const refs = []
  let stateIndex = 0
  let refIndex = 0
  const submissions = []
  const input = {
    style: {}, scrollHeight: 56,
    getBoundingClientRect: () => ({ width: 300 })
  }
  const exports = {}
  const source = fs.readFileSync(require.resolve('../src/renderer/src/components/ChatWidgets.tsx'), 'utf8')
  vm.runInNewContext(ts.transpileModule(source, {
    compilerOptions: { module: ts.ModuleKind.CommonJS, target: ts.ScriptTarget.ES2022, jsx: ts.JsxEmit.ReactJSX }
  }).outputText, {
    exports,
    window: { getComputedStyle: () => ({ lineHeight: '20px', paddingTop: '10px', paddingBottom: '10px', borderTopWidth: '0px', borderBottomWidth: '0px', minHeight: '56px' }) },
    ResizeObserver: class {
      constructor(callback) { resizeCallback = callback }
      observe(element) { assert.equal(element, input) }
      disconnect() { disconnected = true }
    },
    require(name) {
      if (name === '../i18n') return { t: key => key, useLocaleRender() {} }
      if (name === './chatAttachments') return {}
      if (name === './ChatTextContextMenu') return { ChatTextContextMenu: () => null }
      if (name === './ChatImageAttachments') return { ChatImageAttachments: () => null }
      if (name === './ChatCodeBlock') return {}
      if (name === 'react') return {
        ...React,
        useState(initial) {
          const index = stateIndex++
          if (!(index in states)) states[index] = initial
          return [states[index], value => { states[index] = value }]
        },
        useRef(initial) { return refs[refIndex++] ??= { current: initial } },
        useEffect(callback) { effects.push(callback) },
        useLayoutEffect(callback) { layoutEffects.push(callback) }
      }
      return require(name)
    }
  })
  function find(node, type) {
    if (!React.isValidElement(node)) return null
    if (node.type === type) return node
    return React.Children.toArray(node.props.children).map(child => find(child, type)).find(Boolean)
  }
  function render() {
    stateIndex = 0
    refIndex = 0
    layoutEffects = []
    effects = []
    const tree = exports.QaInputBox.type({ dark: true, busy: false, disabled: false, onStop() {}, onSubmit: content => submissions.push(content) })
    const textarea = find(tree, 'textarea')
    textarea.props.ref.current = input
    layoutEffects.forEach(callback => callback())
    return textarea
  }
  return {
    input, render, submissions,
    mountEffects: () => effects.map(callback => callback()),
    resize: width => resizeCallback([{ contentRect: { width } }]),
    disconnected: () => disconnected
  }
}

test('input grows to eight visible lines and scrolls only above the cap', () => {
  const h = harness()
  h.render()
  assert.equal(h.input.style.height, '56px')
  assert.equal(h.input.style.overflowY, 'hidden')
  h.input.scrollHeight = 100
  h.render()
  assert.equal(h.input.style.height, '100px')
  h.input.scrollHeight = 180
  h.render()
  assert.equal(h.input.style.height, '180px')
  assert.equal(h.input.style.overflowY, 'hidden')
  h.input.scrollHeight = 300
  h.render()
  assert.equal(h.input.style.height, '180px')
  assert.equal(h.input.style.overflowY, 'auto')
})

test('deleting text and submitting restore the initial height', () => {
  const h = harness()
  let textarea = h.render()
  textarea.props.onChange({ target: { value: 'question\nsecond line\nthird line' } })
  h.input.scrollHeight = 80
  textarea = h.render()
  assert.equal(h.input.style.height, '80px')
  let prevented = false
  textarea.props.onKeyDown({ key: 'Enter', shiftKey: false, nativeEvent: {}, preventDefault() { prevented = true } })
  assert.equal(prevented, true)
  assert.equal(h.submissions.length, 1)
  h.input.scrollHeight = 40
  textarea = h.render()
  assert.equal(textarea.props.value, '')
  assert.equal(h.input.style.height, '56px')
  assert.equal(h.input.style.overflowY, 'hidden')
})

test('Shift+Enter and IME composition do not submit', () => {
  const h = harness()
  let textarea = h.render()
  textarea.props.onChange({ target: { value: 'question' } })
  textarea = h.render()
  const preventDefault = () => assert.fail('newline or composing Enter must not be intercepted')
  textarea.props.onKeyDown({ key: 'Enter', shiftKey: true, nativeEvent: {}, preventDefault })
  textarea.props.onKeyDown({ key: 'Enter', shiftKey: false, nativeEvent: { isComposing: true }, preventDefault })
  assert.equal(h.submissions.length, 0)
})

test('panel width changes recalculate wrapped lines and observer disconnects on unmount', () => {
  const h = harness()
  h.render()
  const cleanups = h.mountEffects()
  h.input.scrollHeight = 120
  h.resize(180)
  assert.equal(h.input.style.height, '120px')
  h.input.scrollHeight = 50
  h.resize(400)
  assert.equal(h.input.style.height, '56px')
  cleanups.forEach(cleanup => cleanup?.())
  assert.equal(h.disconnected(), true)
})