1  import sliceAnsi from '../utils/sliceAnsi.js'
 2  import { stringWidth } from './stringWidth.js'
 3  import type { Styles } from './styles.js'
 4  import { wrapAnsi } from './wrapAnsi.js'
 5  
 6  const ELLIPSIS = '…'
 7  
 8  // sliceAnsi may include a boundary-spanning wide char (e.g. CJK at position
 9  // end-1 with width 2 overshoots by 1). Retry with a tighter bound once.
10  function sliceFit(text: string, start: number, end: number): string {
11    const s = sliceAnsi(text, start, end)
12    return stringWidth(s) > end - start ? sliceAnsi(text, start, end - 1) : s
13  }
14  
15  function truncate(
16    text: string,
17    columns: number,
18    position: 'start' | 'middle' | 'end',
19  ): string {
20    if (columns < 1) return ''
21    if (columns === 1) return ELLIPSIS
22  
23    const length = stringWidth(text)
24    if (length <= columns) return text
25  
26    if (position === 'start') {
27      return ELLIPSIS + sliceFit(text, length - columns + 1, length)
28    }
29    if (position === 'middle') {
30      const half = Math.floor(columns / 2)
31      return (
32        sliceFit(text, 0, half) +
33        ELLIPSIS +
34        sliceFit(text, length - (columns - half) + 1, length)
35      )
36    }
37    return sliceFit(text, 0, columns - 1) + ELLIPSIS
38  }
39  
40  export default function wrapText(
41    text: string,
42    maxWidth: number,
43    wrapType: Styles['textWrap'],
44  ): string {
45    if (wrapType === 'wrap') {
46      return wrapAnsi(text, maxWidth, {
47        trim: false,
48        hard: true,
49      })
50    }
51  
52    if (wrapType === 'wrap-trim') {
53      return wrapAnsi(text, maxWidth, {
54        trim: true,
55        hard: true,
56      })
57    }
58  
59    if (wrapType!.startsWith('truncate')) {
60      let position: 'end' | 'middle' | 'start' = 'end'
61  
62      if (wrapType === 'truncate-middle') {
63        position = 'middle'
64      }
65  
66      if (wrapType === 'truncate-start') {
67        position = 'start'
68      }
69  
70      return truncate(text, maxWidth, position)
71    }
72  
73    return text
74  }