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