1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
/**
* @license Apache-2.0
*
* Copyright (c) 2019 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// MODULES //
var repeat = require( '@stdlib/string/repeat' );
var escapeCode = require( './ansi_escape_code.js' );
var fillLine = require( './fill_line.js' );
// VARIABLES //
var RESET = escapeCode( 'RESET' );
var ESC = RESET[ 0 ];
var END = RESET[ RESET.length-1 ]; // Note: last character should be the same for all ANSI escape codes
var DEFAULT_PATTERN = '-';
var RE_UTF16_HIGH_SURROGATE = /[\uD800-\uDBFF]/; // TODO: use stdlib package
// MAIN //
/**
* Generates a horizontal rule.
*
* @private
* @param {PositiveInteger} width - slide width
* @param {string} pattern - rule pattern
* @param {NonNegativeInteger} len - effective pattern length
* @param {string} fill - fill character
* @param {NonNegativeInteger} padding - padding
* @returns {string} horizontal rule
*/
function rule( width, pattern, len, fill, padding ) {
var reset;
var ANSI;
var rlen;
var left;
var str;
var rem;
var ch;
var N;
var i;
if ( pattern === '' ) {
pattern = DEFAULT_PATTERN;
len = pattern.length;
}
reset = '';
// Determine the number of complete repeats:
rlen = width - padding;
N = ( rlen/len )|0; // Note: assume never greater than 2^31-1!
// Generate an initial rule consisting of a whole number of repeats:
str = repeat( pattern, N );
// Handle whatever is remaining...
rem = rlen - (len*N);
if ( rem > 0 ) {
for ( i = 0; i < pattern.length; i++ ) {
ch = pattern[ i ];
// Note: order matters for what follows...
if ( ch === END ) {
// Disable the `ANSI` flag upon closing an ANSI escape code...
if ( ANSI ) {
ANSI = false;
}
str += ch;
continue;
}
// Ensure we retain ANSI escape codes...
if ( ANSI ) {
str += ch;
continue;
}
// If we encounter an ASCI escape sequence, toggle the `ANSI` flag...
if ( ch === ESC ) {
str += ch;
ANSI = true;
reset += RESET; // ensure we reset styles in the event we cut the pattern string before it includes such a reset
continue;
}
// Do not cut surrogate pairs...
if ( RE_UTF16_HIGH_SURROGATE.test( ch ) ) {
if ( rem <= 1 ) {
str += fill;
break;
}
str += ch;
rem -= 1;
continue;
}
// Pattern character...
str += ch;
rem -= 1;
if ( rem === 0 ) {
break;
}
}
}
left = (padding/2)|0; // Note: assume never greater than 2^31-1!
return fillLine( str+reset, fill, left, padding-left );
}
// EXPORTS //
module.exports = rule;
|
