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1import stringWidth from 'string-width';
2import stripAnsi from 'strip-ansi';
3import ansiStyles from 'ansi-styles';
4
5const ESCAPES = new Set([
6	'\u001B',
7	'\u009B',
8]);
9
10const END_CODE = 39;
11const ANSI_ESCAPE_BELL = '\u0007';
12const ANSI_CSI = '[';
13const ANSI_OSC = ']';
14const ANSI_SGR_TERMINATOR = 'm';
15const ANSI_ESCAPE_LINK = `${ANSI_OSC}8;;`;
16
17const wrapAnsiCode = code => `${ESCAPES.values().next().value}${ANSI_CSI}${code}${ANSI_SGR_TERMINATOR}`;
18const wrapAnsiHyperlink = uri => `${ESCAPES.values().next().value}${ANSI_ESCAPE_LINK}${uri}${ANSI_ESCAPE_BELL}`;
19
20// Calculate the length of words split on ' ', ignoring
21// the extra characters added by ansi escape codes
22const wordLengths = string => string.split(' ').map(character => stringWidth(character));
23
24// Wrap a long word across multiple rows
25// Ansi escape codes do not count towards length
26const wrapWord = (rows, word, columns) => {
27	const characters = [...word];
28
29	let isInsideEscape = false;
30	let isInsideLinkEscape = false;
31	let visible = stringWidth(stripAnsi(rows[rows.length - 1]));
32
33	for (const [index, character] of characters.entries()) {
34		const characterLength = stringWidth(character);
35
36		if (visible + characterLength <= columns) {
37			rows[rows.length - 1] += character;
38		} else {
39			rows.push(character);
40			visible = 0;
41		}
42
43		if (ESCAPES.has(character)) {
44			isInsideEscape = true;
45			isInsideLinkEscape = characters.slice(index + 1).join('').startsWith(ANSI_ESCAPE_LINK);
46		}
47
48		if (isInsideEscape) {
49			if (isInsideLinkEscape) {
50				if (character === ANSI_ESCAPE_BELL) {
51					isInsideEscape = false;
52					isInsideLinkEscape = false;
53				}
54			} else if (character === ANSI_SGR_TERMINATOR) {
55				isInsideEscape = false;
56			}
57
58			continue;
59		}
60
61		visible += characterLength;
62
63		if (visible === columns && index < characters.length - 1) {
64			rows.push('');
65			visible = 0;
66		}
67	}
68
69	// It's possible that the last row we copy over is only
70	// ansi escape characters, handle this edge-case
71	if (!visible && rows[rows.length - 1].length > 0 && rows.length > 1) {
72		rows[rows.length - 2] += rows.pop();
73	}
74};
75
76// Trims spaces from a string ignoring invisible sequences
77const stringVisibleTrimSpacesRight = string => {
78	const words = string.split(' ');
79	let last = words.length;
80
81	while (last > 0) {
82		if (stringWidth(words[last - 1]) > 0) {
83			break;
84		}
85
86		last--;
87	}
88
89	if (last === words.length) {
90		return string;
91	}
92
93	return words.slice(0, last).join(' ') + words.slice(last).join('');
94};
95
96// The wrap-ansi module can be invoked in either 'hard' or 'soft' wrap mode
97//
98// 'hard' will never allow a string to take up more than columns characters
99//
100// 'soft' allows long words to expand past the column length
101const exec = (string, columns, options = {}) => {
102	if (options.trim !== false && string.trim() === '') {
103		return '';
104	}
105
106	let returnValue = '';
107	let escapeCode;
108	let escapeUrl;
109
110	const lengths = wordLengths(string);
111	let rows = [''];
112
113	for (const [index, word] of string.split(' ').entries()) {
114		if (options.trim !== false) {
115			rows[rows.length - 1] = rows[rows.length - 1].trimStart();
116		}
117
118		let rowLength = stringWidth(rows[rows.length - 1]);
119
120		if (index !== 0) {
121			if (rowLength >= columns && (options.wordWrap === false || options.trim === false)) {
122				// If we start with a new word but the current row length equals the length of the columns, add a new row
123				rows.push('');
124				rowLength = 0;
125			}
126
127			if (rowLength > 0 || options.trim === false) {
128				rows[rows.length - 1] += ' ';
129				rowLength++;
130			}
131		}
132
133		// In 'hard' wrap mode, the length of a line is never allowed to extend past 'columns'
134		if (options.hard && lengths[index] > columns) {
135			const remainingColumns = (columns - rowLength);
136			const breaksStartingThisLine = 1 + Math.floor((lengths[index] - remainingColumns - 1) / columns);
137			const breaksStartingNextLine = Math.floor((lengths[index] - 1) / columns);
138			if (breaksStartingNextLine < breaksStartingThisLine) {
139				rows.push('');
140			}
141
142			wrapWord(rows, word, columns);
143			continue;
144		}
145
146		if (rowLength + lengths[index] > columns && rowLength > 0 && lengths[index] > 0) {
147			if (options.wordWrap === false && rowLength < columns) {
148				wrapWord(rows, word, columns);
149				continue;
150			}
151
152			rows.push('');
153		}
154
155		if (rowLength + lengths[index] > columns && options.wordWrap === false) {
156			wrapWord(rows, word, columns);
157			continue;
158		}
159
160		rows[rows.length - 1] += word;
161	}
162
163	if (options.trim !== false) {
164		rows = rows.map(row => stringVisibleTrimSpacesRight(row));
165	}
166
167	const pre = [...rows.join('\n')];
168
169	for (const [index, character] of pre.entries()) {
170		returnValue += character;
171
172		if (ESCAPES.has(character)) {
173			const {groups} = new RegExp(`(?:\\${ANSI_CSI}(?<code>\\d+)m|\\${ANSI_ESCAPE_LINK}(?<uri>.*)${ANSI_ESCAPE_BELL})`).exec(pre.slice(index).join('')) || {groups: {}};
174			if (groups.code !== undefined) {
175				const code = Number.parseFloat(groups.code);
176				escapeCode = code === END_CODE ? undefined : code;
177			} else if (groups.uri !== undefined) {
178				escapeUrl = groups.uri.length === 0 ? undefined : groups.uri;
179			}
180		}
181
182		const code = ansiStyles.codes.get(Number(escapeCode));
183
184		if (pre[index + 1] === '\n') {
185			if (escapeUrl) {
186				returnValue += wrapAnsiHyperlink('');
187			}
188
189			if (escapeCode && code) {
190				returnValue += wrapAnsiCode(code);
191			}
192		} else if (character === '\n') {
193			if (escapeCode && code) {
194				returnValue += wrapAnsiCode(escapeCode);
195			}
196
197			if (escapeUrl) {
198				returnValue += wrapAnsiHyperlink(escapeUrl);
199			}
200		}
201	}
202
203	return returnValue;
204};
205
206// For each newline, invoke the method separately
207export default function wrapAnsi(string, columns, options) {
208	return String(string)
209		.normalize()
210		.replace(/\r\n/g, '\n')
211		.split('\n')
212		.map(line => exec(line, columns, options))
213		.join('\n');
214}
215