Function useVimInput

src/hooks/useVimInput.ts:34–316

(props: UseVimInputProps)

}

export function useVimInput(props: UseVimInputProps): VimInputState {
  const vimStateRef = React.useRef<VimState>(createInitialVimState())
  const [mode, setMode] = useState<VimMode>('INSERT')

  const persistentRef = React.useRef<PersistentState>(
    createInitialPersistentState(),
  )

  // inputFilter is applied once at the top of handleVimInput (not here) so
  // vim-handled paths that return without calling textInput.onInput still
  // run the filter — otherwise a stateful filter (e.g. lazy-space-after-
  // pill) stays armed across an Escape → NORMAL → INSERT round-trip.
  const textInput = useTextInput({ ...props, inputFilter: undefined })
  const { onModeChange, inputFilter } = props

  const switchToInsertMode = useCallback(
    (offset?: number): void => {
      if (offset !== undefined) {
        textInput.setOffset(offset)
      }
      vimStateRef.current = { mode: 'INSERT', insertedText: '' }
      setMode('INSERT')
      onModeChange?.('INSERT')
    },
    [textInput, onModeChange],
  )

  const switchToNormalMode = useCallback((): void => {
    const current = vimStateRef.current
    if (current.mode === 'INSERT' && current.insertedText) {
      persistentRef.current.lastChange = {
        type: 'insert',
        text: current.insertedText,
      }
    }

    // Vim behavior: move cursor left by 1 when exiting insert mode
    // (unless at beginning of line or at offset 0)
    const offset = textInput.offset
    if (offset > 0 && props.value[offset - 1] !== '\n') {
      textInput.setOffset(offset - 1)
    }

    vimStateRef.current = { mode: 'NORMAL', command: { type: 'idle' } }
    setMode('NORMAL')
    onModeChange?.('NORMAL')
  }, [onModeChange, textInput, props.value])

  function createOperatorContext(
    cursor: Cursor,
    isReplay: boolean = false,
  ): OperatorContext {
    return {
      cursor,
      text: props.value,
      setText: (newText: string) => props.onChange(newText),
      setOffset: (offset: number) => textInput.setOffset(offset),
      enterInsert: (offset: number) => switchToInsertMode(offset),