1 const Base64 = {
2 _keyStr: 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=',
3 _utf8_encode: function(string:string) {
4 string = string.replace(/\r\n/g, '\n')
5 let utftext = ''
6 for (let n = 0; n < string.length; n++) {
7 const c = string.charCodeAt(n)
8 if (c < 128) {
9 utftext += String.fromCharCode(c)
10 } else if ((c > 127) && (c < 2048)) {
11 utftext += String.fromCharCode((c >> 6) | 192)
12 utftext += String.fromCharCode((c & 63) | 128)
13 } else {
14 utftext += String.fromCharCode((c >> 12) | 224)
15 utftext += String.fromCharCode(((c >> 6) & 63) | 128)
16 utftext += String.fromCharCode((c & 63) | 128)
17 }
18 }
19 return utftext
20 },
21 _utf8_decode: function(utftext:string) {
22 let string = ''
23 let i = 0
24 let c = 0
25 let c1 = 0
26 let c2 = 0
27 while (i < utftext.length) {
28 c = utftext.charCodeAt(i)
29 if (c < 128) {
30 string += String.fromCharCode(c)
31 i++
32 } else if ((c > 191) && (c < 224)) {
33 c1 = utftext.charCodeAt(i + 1)
34 string += String.fromCharCode(((c & 31) << 6) | (c1 & 63))
35 i += 2
36 } else {
37 c1 = utftext.charCodeAt(i + 1)
38 c2 = utftext.charCodeAt(i + 2)
39 string += String.fromCharCode(((c & 15) << 12) | ((c1 & 63) << 6) | (c2 & 63))
40 i += 3
41 }
42 }
43 return string
44 },
45 encode: function(input:string) {
46 let output = ''
47 let chr1, chr2, chr3, enc1, enc2, enc3, enc4
48 let i = 0
49 input = this._utf8_encode(input)
50 while (i < input.length) {
51 chr1 = input.charCodeAt(i++)
52 chr2 = input.charCodeAt(i++)
53 chr3 = input.charCodeAt(i++)
54 enc1 = chr1 >> 2
55 enc2 = ((chr1 & 3) << 4) | (chr2 >> 4)
56 enc3 = ((chr2 & 15) << 2) | (chr3 >> 6)
57 enc4 = chr3 & 63
58 if (isNaN(chr2)) {
59 enc3 = enc4 = 64
60 } else if (isNaN(chr3)) {
61 enc4 = 64
62 }
63 output = output +
64 this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
65 this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4)
66 }
67 return output
68 },
69 decode: function(input:string) {
70 let output = ''
71 let chr1, chr2, chr3
72 let enc1, enc2, enc3, enc4
73 let i = 0
74 // eslint-disable-next-line no-useless-escape
75 input = input.replace(/[^A-Za-z0-9\+\/\=]/g, '')
76 while (i < input.length) {
77 enc1 = this._keyStr.indexOf(input.charAt(i++))
78 enc2 = this._keyStr.indexOf(input.charAt(i++))
79 enc3 = this._keyStr.indexOf(input.charAt(i++))
80 enc4 = this._keyStr.indexOf(input.charAt(i++))
81 chr1 = (enc1 << 2) | (enc2 >> 4)
82 chr2 = ((enc2 & 15) << 4) | (enc3 >> 2)
83 chr3 = ((enc3 & 3) << 6) | enc4
84 output = output + String.fromCharCode(chr1)
85 if (enc3 !== 64) {
86 output = output + String.fromCharCode(chr2)
87 }
88 if (enc4 !== 64) {
89 output = output + String.fromCharCode(chr3)
90 }
91 }
92 output = this._utf8_decode(output)
93 return output
94 }
95 }
96
97 const base64 = {
98 encode: Base64.encode.bind(Base64),
99 decode: Base64.decode.bind(Base64)
100 }
101
102 export default base64
