-
-
Notifications
You must be signed in to change notification settings - Fork 690
Expand file tree
/
Copy pathansi.go
More file actions
394 lines (374 loc) · 10.8 KB
/
Copy pathansi.go
File metadata and controls
394 lines (374 loc) · 10.8 KB
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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
package tview
import (
"bytes"
"fmt"
"io"
"strconv"
"strings"
)
// The states of the ANSI escape code parser.
const (
ansiText = iota
ansiEscape
ansiSubstring
ansiControlSequence
ansiStyleTagOpened
ansiStyleTagForeground
ansiStyleTagBackground
ansiStyleTagAttrs
ansiStyleTagURL
)
// ansi is a io.Writer which translates ANSI escape codes into tview color
// tags.
type ansi struct {
io.Writer
// Reusable buffers.
buffer *bytes.Buffer // The entire output text of one Write().
csiParameter, csiIntermediate *bytes.Buffer // Partial CSI strings.
attributes string // The buffer's current text attributes (a tview attribute string).
// The current state of the parser. One of the ansi constants.
state int
}
// ANSIWriter returns an io.Writer which translates any ANSI escape codes
// written to it into tview style tags. Other escape codes don't have an effect
// and are simply removed. The translated text is written to the provided
// writer.
func ANSIWriter(writer io.Writer) io.Writer {
return &ansi{
Writer: writer,
buffer: new(bytes.Buffer),
csiParameter: new(bytes.Buffer),
csiIntermediate: new(bytes.Buffer),
state: ansiText,
}
}
// Write parses the given text as a string of runes, translates ANSI escape
// codes to style tags and writes them to the output writer.
func (a *ansi) Write(text []byte) (int, error) {
defer func() {
a.buffer.Reset()
}()
// Helper function which checks if the given byte is one of a list of
// characters, including letters and digits.
isOneOf := func(r rune, chars string) bool {
if r >= 'a' && r <= 'z' || r >= 'A' && r <= 'Z' || r >= '0' && r <= '9' {
return true
}
return strings.IndexRune(chars, r) >= 0
}
for _, r := range string(text) {
switch a.state {
case ansiEscape:
switch r {
case '[': // Control Sequence Introducer.
a.csiParameter.Reset()
a.csiIntermediate.Reset()
a.state = ansiControlSequence
case 'c': // Reset.
fmt.Fprint(a.buffer, "[-:-:-]")
a.state = ansiText
case 'P', ']', 'X', '^', '_': // Substrings and commands.
a.state = ansiSubstring
default: // Ignore.
a.state = ansiText
}
case ansiControlSequence:
switch {
case r >= 0x30 && r <= 0x3f: // '0' - '?' (includes numbers), parameter bytes.
if _, err := a.csiParameter.WriteRune(r); err != nil {
return 0, err
}
case r >= 0x20 && r <= 0x2f: // ' ' - '/', intermediate bytes.
if _, err := a.csiIntermediate.WriteRune(r); err != nil {
return 0, err
}
case r >= 0x40 && r <= 0x7e: // '@' - '~' (includes all letters), final byte.
switch r {
case 'E': // Next line.
count, _ := strconv.Atoi(a.csiParameter.String())
if count == 0 {
count = 1
}
fmt.Fprint(a.buffer, strings.Repeat("\n", count))
case 'm': // Select Graphic Rendition.
var background, foreground string
params := a.csiParameter.String()
fields := strings.Split(params, ";")
if len(params) == 0 || fields[0] == "" || fields[0] == "0" {
// Reset.
foreground = "-"
background = "-"
a.attributes = "-"
}
lookupColor := func(colorNumber int) string {
if colorNumber < 0 || colorNumber > 15 {
return "black"
}
return []string{
"black",
"maroon",
"green",
"olive",
"navy",
"purple",
"teal",
"silver",
"gray",
"red",
"lime",
"yellow",
"blue",
"fuchsia",
"aqua",
"white",
}[colorNumber]
}
FieldLoop:
for index, field := range fields {
switch field {
case "0", "00":
foreground = "-"
background = "-"
a.attributes = "-"
case "1", "01":
if !strings.ContainsRune(a.attributes, 'b') {
a.attributes += "b"
}
case "2", "02":
if !strings.ContainsRune(a.attributes, 'd') {
a.attributes += "d"
}
case "3", "03":
if !strings.ContainsRune(a.attributes, 'i') {
a.attributes += "i"
}
case "4", "04":
if !strings.ContainsRune(a.attributes, 'u') {
a.attributes += "u"
}
case "5", "05":
if !strings.ContainsRune(a.attributes, 'l') {
a.attributes += "l"
}
case "7", "07":
if !strings.ContainsRune(a.attributes, 'r') {
a.attributes += "r"
}
case "9", "09":
if !strings.ContainsRune(a.attributes, 's') {
a.attributes += "s"
}
case "22":
if i := strings.IndexRune(a.attributes, 'b'); i >= 0 {
a.attributes = a.attributes[:i] + a.attributes[i+1:]
}
if i := strings.IndexRune(a.attributes, 'd'); i >= 0 {
a.attributes = a.attributes[:i] + a.attributes[i+1:]
}
case "23":
if i := strings.IndexRune(a.attributes, 'i'); i >= 0 {
a.attributes = a.attributes[:i] + a.attributes[i+1:]
}
case "24":
if i := strings.IndexRune(a.attributes, 'u'); i >= 0 {
a.attributes = a.attributes[:i] + a.attributes[i+1:]
}
case "25":
if i := strings.IndexRune(a.attributes, 'l'); i >= 0 {
a.attributes = a.attributes[:i] + a.attributes[i+1:]
}
case "27":
if i := strings.IndexRune(a.attributes, 'r'); i >= 0 {
a.attributes = a.attributes[:i] + a.attributes[i+1:]
}
case "29":
if i := strings.IndexRune(a.attributes, 's'); i >= 0 {
a.attributes = a.attributes[:i] + a.attributes[i+1:]
}
case "30", "31", "32", "33", "34", "35", "36", "37":
colorNumber, _ := strconv.Atoi(field)
foreground = lookupColor(colorNumber - 30)
case "39":
foreground = "-"
case "40", "41", "42", "43", "44", "45", "46", "47":
colorNumber, _ := strconv.Atoi(field)
background = lookupColor(colorNumber - 40)
case "49":
background = "-"
case "90", "91", "92", "93", "94", "95", "96", "97":
colorNumber, _ := strconv.Atoi(field)
foreground = lookupColor(colorNumber - 82)
case "100", "101", "102", "103", "104", "105", "106", "107":
colorNumber, _ := strconv.Atoi(field)
background = lookupColor(colorNumber - 92)
case "38", "48":
var color string
if len(fields) > index+1 {
if fields[index+1] == "5" && len(fields) > index+2 { // 8-bit colors.
colorNumber, _ := strconv.Atoi(fields[index+2])
if colorNumber <= 15 {
color = lookupColor(colorNumber)
} else if colorNumber <= 231 {
red := (colorNumber - 16) / 36
green := ((colorNumber - 16) / 6) % 6
blue := (colorNumber - 16) % 6
color = fmt.Sprintf("#%02x%02x%02x", 255*red/5, 255*green/5, 255*blue/5)
} else if colorNumber <= 255 {
grey := 255 * (colorNumber - 232) / 23
color = fmt.Sprintf("#%02x%02x%02x", grey, grey, grey)
}
} else if fields[index+1] == "2" && len(fields) > index+4 { // 24-bit colors.
red, _ := strconv.Atoi(fields[index+2])
green, _ := strconv.Atoi(fields[index+3])
blue, _ := strconv.Atoi(fields[index+4])
color = fmt.Sprintf("#%02x%02x%02x", red, green, blue)
}
}
if len(color) > 0 {
if field == "38" {
foreground = color
} else {
background = color
}
}
break FieldLoop
}
}
var colon string
if len(a.attributes) > 1 && a.attributes[0] == '-' {
a.attributes = a.attributes[1:]
}
if len(a.attributes) > 0 {
colon = ":"
}
if len(foreground) > 0 || len(background) > 0 || len(a.attributes) > 0 {
fmt.Fprintf(a.buffer, "[%s:%s%s%s]", foreground, background, colon, a.attributes)
}
}
a.state = ansiText
default: // Undefined byte.
a.state = ansiText // Abort CSI.
}
case ansiSubstring:
if r == 27 { // Most likely the end of the substring.
a.state = ansiEscape
} // Ignore all other characters.
case ansiStyleTagOpened:
switch {
case isOneOf(r, "#-"):
a.state = ansiStyleTagForeground
case r == ':':
a.state = ansiStyleTagBackground
case r == 27:
a.state = ansiEscape
default:
a.state = ansiText // Nevermind. Not a style tag.
}
if _, err := a.buffer.WriteRune(r); err != nil {
return 0, err
}
case ansiStyleTagForeground:
switch {
case isOneOf(r, "#-"):
break
case r == ':':
a.state = ansiStyleTagBackground
case r == ']':
// This is the end of a style tag. Escape it.
if _, err := a.buffer.WriteRune('['); err != nil {
return 0, err
}
a.state = ansiText
case r == 27:
a.state = ansiEscape
default:
a.state = ansiText // Nevermind. Not a style tag.
}
if _, err := a.buffer.WriteRune(r); err != nil {
return 0, err
}
case ansiStyleTagBackground:
switch {
case isOneOf(r, "#-"):
break
case r == ':':
a.state = ansiStyleTagAttrs
case r == ']':
// This is the end of a style tag. Escape it.
if _, err := a.buffer.WriteRune('['); err != nil {
return 0, err
}
a.state = ansiText
case r == 27:
a.state = ansiEscape
default:
a.state = ansiText // Nevermind. Not a style tag.
}
if _, err := a.buffer.WriteRune(r); err != nil {
return 0, err
}
case ansiStyleTagAttrs:
switch {
case isOneOf(r, "-"):
break
case r == ':':
a.state = ansiStyleTagURL
case r == ']':
// This is the end of a style tag. Escape it.
if _, err := a.buffer.WriteRune('['); err != nil {
return 0, err
}
a.state = ansiText
case r == 27:
a.state = ansiEscape
default:
a.state = ansiText // Nevermind. Not a style tag.
}
if _, err := a.buffer.WriteRune(r); err != nil {
return 0, err
}
case ansiStyleTagURL:
switch {
case r == ']':
// This is the end of a style tag. Escape it.
if _, err := a.buffer.WriteRune('['); err != nil {
return 0, err
}
a.state = ansiText
case r == 27:
a.state = ansiEscape
}
if _, err := a.buffer.WriteRune(r); err != nil {
return 0, err
}
default:
if r == 27 {
// This is the start of an escape sequence.
a.state = ansiEscape
} else {
// Just a regular rune. Keep track of style tags so we can
// escape them if they are part of the text.
if r == '[' {
a.state = ansiStyleTagOpened
}
if _, err := a.buffer.WriteRune(r); err != nil {
return 0, err
}
}
}
}
// Write buffer to target writer.
n, err := a.buffer.WriteTo(a.Writer)
if err != nil {
return int(n), err
}
return len(text), nil
}
// TranslateANSI replaces ANSI escape sequences found in the provided string
// with tview's style tags and returns the resulting string.
func TranslateANSI(text string) string {
var buffer bytes.Buffer
writer := ANSIWriter(&buffer)
writer.Write([]byte(text))
return buffer.String()
}