]> git.lizzy.rs Git - micro.git/blob - cmd/micro/view.go
Merge pull request #499 from 10sr/addrmtrailingws
[micro.git] / cmd / micro / view.go
1 package main
2
3 import (
4         "os"
5         "strconv"
6         "strings"
7         "time"
8
9         "github.com/mattn/go-runewidth"
10         "github.com/mitchellh/go-homedir"
11         "github.com/zyedidia/tcell"
12 )
13
14 type ViewType int
15
16 const (
17         vtDefault ViewType = iota
18         vtHelp
19         vtLog
20 )
21
22 // The View struct stores information about a view into a buffer.
23 // It stores information about the cursor, and the viewport
24 // that the user sees the buffer from.
25 type View struct {
26         // A pointer to the buffer's cursor for ease of access
27         Cursor *Cursor
28
29         // The topmost line, used for vertical scrolling
30         Topline int
31         // The leftmost column, used for horizontal scrolling
32         leftCol int
33
34         // Specifies whether or not this view holds a help buffer
35         Type ViewType
36
37         // Actual width and height
38         Width  int
39         Height int
40
41         LockWidth  bool
42         LockHeight bool
43
44         // Where this view is located
45         x, y int
46
47         // How much to offset because of line numbers
48         lineNumOffset int
49
50         // Holds the list of gutter messages
51         messages map[string][]GutterMessage
52
53         // This is the index of this view in the views array
54         Num int
55         // What tab is this view stored in
56         TabNum int
57
58         // The buffer
59         Buf *Buffer
60         // The statusline
61         sline Statusline
62
63         // Since tcell doesn't differentiate between a mouse release event
64         // and a mouse move event with no keys pressed, we need to keep
65         // track of whether or not the mouse was pressed (or not released) last event to determine
66         // mouse release events
67         mouseReleased bool
68
69         // This stores when the last click was
70         // This is useful for detecting double and triple clicks
71         lastClickTime time.Time
72
73         // lastCutTime stores when the last ctrl+k was issued.
74         // It is used for clearing the clipboard to replace it with fresh cut lines.
75         lastCutTime time.Time
76
77         // freshClip returns true if the clipboard has never been pasted.
78         freshClip bool
79
80         // Was the last mouse event actually a double click?
81         // Useful for detecting triple clicks -- if a double click is detected
82         // but the last mouse event was actually a double click, it's a triple click
83         doubleClick bool
84         // Same here, just to keep track for mouse move events
85         tripleClick bool
86
87         // Syntax highlighting matches
88         matches SyntaxMatches
89
90         splitNode *LeafNode
91 }
92
93 // NewView returns a new fullscreen view
94 func NewView(buf *Buffer) *View {
95         screenW, screenH := screen.Size()
96         return NewViewWidthHeight(buf, screenW, screenH)
97 }
98
99 // NewViewWidthHeight returns a new view with the specified width and height
100 // Note that w and h are raw column and row values
101 func NewViewWidthHeight(buf *Buffer, w, h int) *View {
102         v := new(View)
103
104         v.x, v.y = 0, 0
105
106         v.Width = w
107         v.Height = h
108
109         v.ToggleTabbar()
110
111         v.OpenBuffer(buf)
112
113         v.messages = make(map[string][]GutterMessage)
114
115         v.sline = Statusline{
116                 view: v,
117         }
118
119         if v.Buf.Settings["statusline"].(bool) {
120                 v.Height--
121         }
122
123         for pl := range loadedPlugins {
124                 _, err := Call(pl+".onViewOpen", v)
125                 if err != nil && !strings.HasPrefix(err.Error(), "function does not exist") {
126                         TermMessage(err)
127                         continue
128                 }
129         }
130
131         return v
132 }
133
134 // ToggleStatusLine creates an extra row for the statusline if necessary
135 func (v *View) ToggleStatusLine() {
136         if v.Buf.Settings["statusline"].(bool) {
137                 v.Height--
138         } else {
139                 v.Height++
140         }
141 }
142
143 // ToggleTabbar creates an extra row for the tabbar if necessary
144 func (v *View) ToggleTabbar() {
145         if len(tabs) > 1 {
146                 if v.y == 0 {
147                         // Include one line for the tab bar at the top
148                         v.Height--
149                         v.y = 1
150                 }
151         } else {
152                 if v.y == 1 {
153                         v.y = 0
154                         v.Height++
155                 }
156         }
157 }
158
159 func (v *View) paste(clip string) {
160         leadingWS := GetLeadingWhitespace(v.Buf.Line(v.Cursor.Y))
161
162         if v.Cursor.HasSelection() {
163                 v.Cursor.DeleteSelection()
164                 v.Cursor.ResetSelection()
165         }
166         clip = strings.Replace(clip, "\n", "\n"+leadingWS, -1)
167         v.Buf.Insert(v.Cursor.Loc, clip)
168         v.Cursor.Loc = v.Cursor.Loc.Move(Count(clip), v.Buf)
169         v.freshClip = false
170         messenger.Message("Pasted clipboard")
171 }
172
173 // ScrollUp scrolls the view up n lines (if possible)
174 func (v *View) ScrollUp(n int) {
175         // Try to scroll by n but if it would overflow, scroll by 1
176         if v.Topline-n >= 0 {
177                 v.Topline -= n
178         } else if v.Topline > 0 {
179                 v.Topline--
180         }
181 }
182
183 // ScrollDown scrolls the view down n lines (if possible)
184 func (v *View) ScrollDown(n int) {
185         // Try to scroll by n but if it would overflow, scroll by 1
186         if v.Topline+n <= v.Buf.NumLines-v.Height {
187                 v.Topline += n
188         } else if v.Topline < v.Buf.NumLines-v.Height {
189                 v.Topline++
190         }
191 }
192
193 // CanClose returns whether or not the view can be closed
194 // If there are unsaved changes, the user will be asked if the view can be closed
195 // causing them to lose the unsaved changes
196 func (v *View) CanClose() bool {
197         if v.Type == vtDefault && v.Buf.IsModified {
198                 var char rune
199                 var canceled bool
200                 if v.Buf.Settings["autosave"].(bool) {
201                         char = 'y'
202                 } else {
203                         char, canceled = messenger.LetterPrompt("Save changes to "+v.Buf.GetName()+" before closing? (y,n,esc) ", 'y', 'n')
204                 }
205                 if !canceled {
206                         if char == 'y' {
207                                 v.Save(true)
208                                 return true
209                         } else if char == 'n' {
210                                 return true
211                         }
212                 }
213         } else {
214                 return true
215         }
216         return false
217 }
218
219 // OpenBuffer opens a new buffer in this view.
220 // This resets the topline, event handler and cursor.
221 func (v *View) OpenBuffer(buf *Buffer) {
222         screen.Clear()
223         v.CloseBuffer()
224         v.Buf = buf
225         v.Cursor = &buf.Cursor
226         v.Topline = 0
227         v.leftCol = 0
228         v.Cursor.ResetSelection()
229         v.Relocate()
230         v.Center(false)
231         v.messages = make(map[string][]GutterMessage)
232
233         v.matches = Match(v)
234
235         // Set mouseReleased to true because we assume the mouse is not being pressed when
236         // the editor is opened
237         v.mouseReleased = true
238         v.lastClickTime = time.Time{}
239 }
240
241 // Open opens the given file in the view
242 func (v *View) Open(filename string) {
243         home, _ := homedir.Dir()
244         filename = strings.Replace(filename, "~", home, 1)
245         file, err := os.Open(filename)
246         defer file.Close()
247
248         var buf *Buffer
249         if err != nil {
250                 messenger.Message(err.Error())
251                 // File does not exist -- create an empty buffer with that name
252                 buf = NewBuffer(strings.NewReader(""), filename)
253         } else {
254                 buf = NewBuffer(file, filename)
255         }
256         v.OpenBuffer(buf)
257 }
258
259 // CloseBuffer performs any closing functions on the buffer
260 func (v *View) CloseBuffer() {
261         if v.Buf != nil {
262                 v.Buf.Serialize()
263         }
264 }
265
266 // ReOpen reloads the current buffer
267 func (v *View) ReOpen() {
268         if v.CanClose() {
269                 screen.Clear()
270                 v.Buf.ReOpen()
271                 v.Relocate()
272                 v.matches = Match(v)
273         }
274 }
275
276 // HSplit opens a horizontal split with the given buffer
277 func (v *View) HSplit(buf *Buffer) {
278         i := 0
279         if v.Buf.Settings["splitBottom"].(bool) {
280                 i = 1
281         }
282         v.splitNode.HSplit(buf, v.Num+i)
283 }
284
285 // VSplit opens a vertical split with the given buffer
286 func (v *View) VSplit(buf *Buffer) {
287         i := 0
288         if v.Buf.Settings["splitRight"].(bool) {
289                 i = 1
290         }
291         v.splitNode.VSplit(buf, v.Num+i)
292 }
293
294 // HSplitIndex opens a horizontal split with the given buffer at the given index
295 func (v *View) HSplitIndex(buf *Buffer, splitIndex int) {
296         v.splitNode.HSplit(buf, splitIndex)
297 }
298
299 // VSplitIndex opens a vertical split with the given buffer at the given index
300 func (v *View) VSplitIndex(buf *Buffer, splitIndex int) {
301         v.splitNode.VSplit(buf, splitIndex)
302 }
303
304 // GetSoftWrapLocation gets the location of a visual click on the screen and converts it to col,line
305 func (v *View) GetSoftWrapLocation(vx, vy int) (int, int) {
306         if !v.Buf.Settings["softwrap"].(bool) {
307                 vx = v.Cursor.GetCharPosInLine(vy, vx)
308                 return vx, vy
309         }
310
311         screenX, screenY := 0, v.Topline
312         for lineN := v.Topline; lineN < v.Bottomline(); lineN++ {
313                 line := v.Buf.Line(lineN)
314
315                 colN := 0
316                 for _, ch := range line {
317                         if screenX >= v.Width-v.lineNumOffset {
318                                 screenX = 0
319                                 screenY++
320                         }
321
322                         if screenX == vx && screenY == vy {
323                                 return colN, lineN
324                         }
325
326                         if ch == '\t' {
327                                 screenX += int(v.Buf.Settings["tabsize"].(float64)) - 1
328                         }
329
330                         screenX++
331                         colN++
332                 }
333                 if screenY == vy {
334                         return colN, lineN
335                 }
336                 screenX = 0
337                 screenY++
338         }
339
340         return 0, 0
341 }
342
343 func (v *View) Bottomline() int {
344         if !v.Buf.Settings["softwrap"].(bool) {
345                 return v.Topline + v.Height
346         }
347
348         screenX, screenY := 0, 0
349         numLines := 0
350         for lineN := v.Topline; lineN < v.Topline+v.Height; lineN++ {
351                 line := v.Buf.Line(lineN)
352
353                 colN := 0
354                 for _, ch := range line {
355                         if screenX >= v.Width-v.lineNumOffset {
356                                 screenX = 0
357                                 screenY++
358                         }
359
360                         if ch == '\t' {
361                                 screenX += int(v.Buf.Settings["tabsize"].(float64)) - 1
362                         }
363
364                         screenX++
365                         colN++
366                 }
367                 screenX = 0
368                 screenY++
369                 numLines++
370
371                 if screenY >= v.Height {
372                         break
373                 }
374         }
375         return numLines + v.Topline
376 }
377
378 // Relocate moves the view window so that the cursor is in view
379 // This is useful if the user has scrolled far away, and then starts typing
380 func (v *View) Relocate() bool {
381         height := v.Bottomline() - v.Topline
382         ret := false
383         cy := v.Cursor.Y
384         scrollmargin := int(v.Buf.Settings["scrollmargin"].(float64))
385         if cy < v.Topline+scrollmargin && cy > scrollmargin-1 {
386                 v.Topline = cy - scrollmargin
387                 ret = true
388         } else if cy < v.Topline {
389                 v.Topline = cy
390                 ret = true
391         }
392         if cy > v.Topline+height-1-scrollmargin && cy < v.Buf.NumLines-scrollmargin {
393                 v.Topline = cy - height + 1 + scrollmargin
394                 ret = true
395         } else if cy >= v.Buf.NumLines-scrollmargin && cy > height {
396                 v.Topline = v.Buf.NumLines - height
397                 ret = true
398         }
399
400         if !v.Buf.Settings["softwrap"].(bool) {
401                 cx := v.Cursor.GetVisualX()
402                 if cx < v.leftCol {
403                         v.leftCol = cx
404                         ret = true
405                 }
406                 if cx+v.lineNumOffset+1 > v.leftCol+v.Width {
407                         v.leftCol = cx - v.Width + v.lineNumOffset + 1
408                         ret = true
409                 }
410         }
411         return ret
412 }
413
414 // MoveToMouseClick moves the cursor to location x, y assuming x, y were given
415 // by a mouse click
416 func (v *View) MoveToMouseClick(x, y int) {
417         if y-v.Topline > v.Height-1 {
418                 v.ScrollDown(1)
419                 y = v.Height + v.Topline - 1
420         }
421         if y < 0 {
422                 y = 0
423         }
424         if x < 0 {
425                 x = 0
426         }
427
428         x, y = v.GetSoftWrapLocation(x, y)
429         // x = v.Cursor.GetCharPosInLine(y, x)
430         if x > Count(v.Buf.Line(y)) {
431                 x = Count(v.Buf.Line(y))
432         }
433         v.Cursor.X = x
434         v.Cursor.Y = y
435         v.Cursor.LastVisualX = v.Cursor.GetVisualX()
436 }
437
438 // HandleEvent handles an event passed by the main loop
439 func (v *View) HandleEvent(event tcell.Event) {
440         // This bool determines whether the view is relocated at the end of the function
441         // By default it's true because most events should cause a relocate
442         relocate := true
443
444         v.Buf.CheckModTime()
445
446         switch e := event.(type) {
447         case *tcell.EventResize:
448                 // Window resized
449                 tabs[v.TabNum].Resize()
450         case *tcell.EventKey:
451                 // Check first if input is a key binding, if it is we 'eat' the input and don't insert a rune
452                 isBinding := false
453                 if e.Key() != tcell.KeyRune || e.Modifiers() != 0 {
454                         for key, actions := range bindings {
455                                 if e.Key() == key.keyCode {
456                                         if e.Key() == tcell.KeyRune {
457                                                 if e.Rune() != key.r {
458                                                         continue
459                                                 }
460                                         }
461                                         if e.Modifiers() == key.modifiers {
462                                                 relocate = false
463                                                 isBinding = true
464                                                 for _, action := range actions {
465                                                         relocate = action(v, true) || relocate
466                                                         funcName := FuncName(action)
467                                                         if funcName != "main.(*View).ToggleMacro" && funcName != "main.(*View).PlayMacro" {
468                                                                 if recordingMacro {
469                                                                         curMacro = append(curMacro, action)
470                                                                 }
471                                                         }
472                                                 }
473                                                 break
474                                         }
475                                 }
476                         }
477                 }
478                 if !isBinding && e.Key() == tcell.KeyRune {
479                         // Insert a character
480                         if v.Cursor.HasSelection() {
481                                 v.Cursor.DeleteSelection()
482                                 v.Cursor.ResetSelection()
483                         }
484                         v.Buf.Insert(v.Cursor.Loc, string(e.Rune()))
485                         v.Cursor.Right()
486
487                         for pl := range loadedPlugins {
488                                 _, err := Call(pl+".onRune", string(e.Rune()), v)
489                                 if err != nil && !strings.HasPrefix(err.Error(), "function does not exist") {
490                                         TermMessage(err)
491                                 }
492                         }
493
494                         if recordingMacro {
495                                 curMacro = append(curMacro, e.Rune())
496                         }
497                 }
498         case *tcell.EventPaste:
499                 if !PreActionCall("Paste", v) {
500                         break
501                 }
502
503                 v.paste(e.Text())
504
505                 PostActionCall("Paste", v)
506         case *tcell.EventMouse:
507                 x, y := e.Position()
508                 x -= v.lineNumOffset - v.leftCol + v.x
509                 y += v.Topline - v.y
510                 // Don't relocate for mouse events
511                 relocate = false
512
513                 button := e.Buttons()
514
515                 switch button {
516                 case tcell.Button1:
517                         // Left click
518                         if v.mouseReleased {
519                                 v.MoveToMouseClick(x, y)
520                                 if time.Since(v.lastClickTime)/time.Millisecond < doubleClickThreshold {
521                                         if v.doubleClick {
522                                                 // Triple click
523                                                 v.lastClickTime = time.Now()
524
525                                                 v.tripleClick = true
526                                                 v.doubleClick = false
527
528                                                 v.Cursor.SelectLine()
529                                         } else {
530                                                 // Double click
531                                                 v.lastClickTime = time.Now()
532
533                                                 v.doubleClick = true
534                                                 v.tripleClick = false
535
536                                                 v.Cursor.SelectWord()
537                                         }
538                                 } else {
539                                         v.doubleClick = false
540                                         v.tripleClick = false
541                                         v.lastClickTime = time.Now()
542
543                                         v.Cursor.OrigSelection[0] = v.Cursor.Loc
544                                         v.Cursor.CurSelection[0] = v.Cursor.Loc
545                                         v.Cursor.CurSelection[1] = v.Cursor.Loc
546                                 }
547                                 v.mouseReleased = false
548                         } else if !v.mouseReleased {
549                                 v.MoveToMouseClick(x, y)
550                                 if v.tripleClick {
551                                         v.Cursor.AddLineToSelection()
552                                 } else if v.doubleClick {
553                                         v.Cursor.AddWordToSelection()
554                                 } else {
555                                         v.Cursor.SetSelectionEnd(v.Cursor.Loc)
556                                 }
557                         }
558                 case tcell.Button2:
559                         // Middle mouse button was clicked,
560                         // We should paste primary
561                         v.PastePrimary(true)
562                 case tcell.ButtonNone:
563                         // Mouse event with no click
564                         if !v.mouseReleased {
565                                 // Mouse was just released
566
567                                 // Relocating here isn't really necessary because the cursor will
568                                 // be in the right place from the last mouse event
569                                 // However, if we are running in a terminal that doesn't support mouse motion
570                                 // events, this still allows the user to make selections, except only after they
571                                 // release the mouse
572
573                                 if !v.doubleClick && !v.tripleClick {
574                                         v.MoveToMouseClick(x, y)
575                                         v.Cursor.SetSelectionEnd(v.Cursor.Loc)
576                                 }
577                                 v.mouseReleased = true
578                         }
579                 case tcell.WheelUp:
580                         // Scroll up
581                         scrollspeed := int(v.Buf.Settings["scrollspeed"].(float64))
582                         v.ScrollUp(scrollspeed)
583                 case tcell.WheelDown:
584                         // Scroll down
585                         scrollspeed := int(v.Buf.Settings["scrollspeed"].(float64))
586                         v.ScrollDown(scrollspeed)
587                 }
588         }
589
590         if relocate {
591                 v.Relocate()
592         }
593 }
594
595 // GutterMessage creates a message in this view's gutter
596 func (v *View) GutterMessage(section string, lineN int, msg string, kind int) {
597         lineN--
598         gutterMsg := GutterMessage{
599                 lineNum: lineN,
600                 msg:     msg,
601                 kind:    kind,
602         }
603         for _, v := range v.messages {
604                 for _, gmsg := range v {
605                         if gmsg.lineNum == lineN {
606                                 return
607                         }
608                 }
609         }
610         messages := v.messages[section]
611         v.messages[section] = append(messages, gutterMsg)
612 }
613
614 // ClearGutterMessages clears all gutter messages from a given section
615 func (v *View) ClearGutterMessages(section string) {
616         v.messages[section] = []GutterMessage{}
617 }
618
619 // ClearAllGutterMessages clears all the gutter messages
620 func (v *View) ClearAllGutterMessages() {
621         for k := range v.messages {
622                 v.messages[k] = []GutterMessage{}
623         }
624 }
625
626 // Opens the given help page in a new horizontal split
627 func (v *View) openHelp(helpPage string) {
628         if data, err := FindRuntimeFile(RTHelp, helpPage).Data(); err != nil {
629                 TermMessage("Unable to load help text", helpPage, "\n", err)
630         } else {
631                 helpBuffer := NewBuffer(strings.NewReader(string(data)), helpPage+".md")
632                 helpBuffer.name = "Help"
633
634                 if v.Type == vtHelp {
635                         v.OpenBuffer(helpBuffer)
636                 } else {
637                         v.HSplit(helpBuffer)
638                         CurView().Type = vtHelp
639                 }
640         }
641 }
642
643 func (v *View) drawCell(x, y int, ch rune, combc []rune, style tcell.Style) {
644         if x >= v.x && x < v.x+v.Width && y >= v.y && y < v.y+v.Height {
645                 screen.SetContent(x, y, ch, combc, style)
646         }
647 }
648
649 // DisplayView renders the view to the screen
650 func (v *View) DisplayView() {
651         if v.Type == vtLog {
652                 // Log views should always follow the cursor...
653                 v.Relocate()
654         }
655
656         if v.Buf.Settings["syntax"].(bool) {
657                 v.matches = Match(v)
658         }
659
660         // The charNum we are currently displaying
661         // starts at the start of the viewport
662         charNum := Loc{0, v.Topline}
663
664         // Convert the length of buffer to a string, and get the length of the string
665         // We are going to have to offset by that amount
666         maxLineLength := len(strconv.Itoa(v.Buf.NumLines))
667
668         if v.Buf.Settings["ruler"] == true {
669                 // + 1 for the little space after the line number
670                 v.lineNumOffset = maxLineLength + 1
671         } else {
672                 v.lineNumOffset = 0
673         }
674
675         // We need to add to the line offset if there are gutter messages
676         var hasGutterMessages bool
677         for _, v := range v.messages {
678                 if len(v) > 0 {
679                         hasGutterMessages = true
680                 }
681         }
682         if hasGutterMessages {
683                 v.lineNumOffset += 2
684         }
685
686         if v.x != 0 {
687                 // One space for the extra split divider
688                 v.lineNumOffset++
689         }
690
691         // These represent the current screen coordinates
692         screenX, screenY := v.x, v.y-1
693
694         highlightStyle := defStyle
695         curLineN := 0
696
697         // ViewLine is the current line from the top of the viewport
698         for viewLine := 0; viewLine < v.Height; viewLine++ {
699                 screenY++
700                 screenX = v.x
701
702                 // This is the current line number of the buffer that we are drawing
703                 curLineN = viewLine + v.Topline
704
705                 if screenY-v.y >= v.Height {
706                         break
707                 }
708
709                 if v.x != 0 {
710                         // Draw the split divider
711                         v.drawCell(screenX, screenY, '|', nil, defStyle.Reverse(true))
712                         screenX++
713                 }
714
715                 // If the buffer is smaller than the view height we have to clear all this space
716                 if curLineN >= v.Buf.NumLines {
717                         for i := screenX; i < v.x+v.Width; i++ {
718                                 v.drawCell(i, screenY, ' ', nil, defStyle)
719                         }
720
721                         continue
722                 }
723                 line := v.Buf.Line(curLineN)
724
725                 // If there are gutter messages we need to display the '>>' symbol here
726                 if hasGutterMessages {
727                         // msgOnLine stores whether or not there is a gutter message on this line in particular
728                         msgOnLine := false
729                         for k := range v.messages {
730                                 for _, msg := range v.messages[k] {
731                                         if msg.lineNum == curLineN {
732                                                 msgOnLine = true
733                                                 gutterStyle := defStyle
734                                                 switch msg.kind {
735                                                 case GutterInfo:
736                                                         if style, ok := colorscheme["gutter-info"]; ok {
737                                                                 gutterStyle = style
738                                                         }
739                                                 case GutterWarning:
740                                                         if style, ok := colorscheme["gutter-warning"]; ok {
741                                                                 gutterStyle = style
742                                                         }
743                                                 case GutterError:
744                                                         if style, ok := colorscheme["gutter-error"]; ok {
745                                                                 gutterStyle = style
746                                                         }
747                                                 }
748                                                 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
749                                                 screenX++
750                                                 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
751                                                 screenX++
752                                                 if v.Cursor.Y == curLineN && !messenger.hasPrompt {
753                                                         messenger.Message(msg.msg)
754                                                         messenger.gutterMessage = true
755                                                 }
756                                         }
757                                 }
758                         }
759                         // If there is no message on this line we just display an empty offset
760                         if !msgOnLine {
761                                 v.drawCell(screenX, screenY, ' ', nil, defStyle)
762                                 screenX++
763                                 v.drawCell(screenX, screenY, ' ', nil, defStyle)
764                                 screenX++
765                                 if v.Cursor.Y == curLineN && messenger.gutterMessage {
766                                         messenger.Reset()
767                                         messenger.gutterMessage = false
768                                 }
769                         }
770                 }
771
772                 lineNumStyle := defStyle
773                 if v.Buf.Settings["ruler"] == true {
774                         // Write the line number
775                         if style, ok := colorscheme["line-number"]; ok {
776                                 lineNumStyle = style
777                         }
778                         if style, ok := colorscheme["current-line-number"]; ok {
779                                 if curLineN == v.Cursor.Y && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() {
780                                         lineNumStyle = style
781                                 }
782                         }
783
784                         lineNum := strconv.Itoa(curLineN + 1)
785
786                         // Write the spaces before the line number if necessary
787                         for i := 0; i < maxLineLength-len(lineNum); i++ {
788                                 v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
789                                 screenX++
790                         }
791                         // Write the actual line number
792                         for _, ch := range lineNum {
793                                 v.drawCell(screenX, screenY, ch, nil, lineNumStyle)
794                                 screenX++
795                         }
796
797                         // Write the extra space
798                         v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
799                         screenX++
800                 }
801
802                 // Now we actually draw the line
803                 colN := 0
804                 strWidth := 0
805                 tabSize := int(v.Buf.Settings["tabsize"].(float64))
806                 for _, ch := range line {
807                         if v.Buf.Settings["softwrap"].(bool) {
808                                 if screenX-v.x >= v.Width {
809                                         screenY++
810                                         for i := 0; i < v.lineNumOffset; i++ {
811                                                 screen.SetContent(v.x+i, screenY, ' ', nil, lineNumStyle)
812                                         }
813                                         screenX = v.x + v.lineNumOffset
814                                 }
815                         }
816
817                         if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN && colN == v.Cursor.X {
818                                 v.DisplayCursor(screenX-v.leftCol, screenY)
819                         }
820
821                         lineStyle := defStyle
822
823                         if v.Buf.Settings["syntax"].(bool) {
824                                 // Syntax highlighting is enabled
825                                 highlightStyle = v.matches[viewLine][colN]
826                         }
827
828                         if v.Cursor.HasSelection() &&
829                                 (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
830                                         charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
831                                 // The current character is selected
832                                 lineStyle = defStyle.Reverse(true)
833
834                                 if style, ok := colorscheme["selection"]; ok {
835                                         lineStyle = style
836                                 }
837                         } else {
838                                 lineStyle = highlightStyle
839                         }
840
841                         // We need to display the background of the linestyle with the correct color if cursorline is enabled
842                         // and this is the current view and there is no selection on this line and the cursor is on this line
843                         if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
844                                 if style, ok := colorscheme["cursor-line"]; ok {
845                                         fg, _, _ := style.Decompose()
846                                         lineStyle = lineStyle.Background(fg)
847                                 }
848                         }
849
850                         if ch == '\t' {
851                                 // If the character we are displaying is a tab, we need to do a bunch of special things
852
853                                 // First the user may have configured an `indent-char` to be displayed to show that this
854                                 // is a tab character
855                                 lineIndentStyle := defStyle
856                                 if style, ok := colorscheme["indent-char"]; ok && v.Buf.Settings["indentchar"].(string) != " " {
857                                         lineIndentStyle = style
858                                 }
859                                 if v.Cursor.HasSelection() &&
860                                         (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
861                                                 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
862
863                                         lineIndentStyle = defStyle.Reverse(true)
864
865                                         if style, ok := colorscheme["selection"]; ok {
866                                                 lineIndentStyle = style
867                                         }
868                                 }
869                                 if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
870                                         if style, ok := colorscheme["cursor-line"]; ok {
871                                                 fg, _, _ := style.Decompose()
872                                                 lineIndentStyle = lineIndentStyle.Background(fg)
873                                         }
874                                 }
875                                 // Here we get the indent char
876                                 indentChar := []rune(v.Buf.Settings["indentchar"].(string))
877                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
878                                         v.drawCell(screenX-v.leftCol, screenY, indentChar[0], nil, lineIndentStyle)
879                                 }
880                                 // Now the tab has to be displayed as a bunch of spaces
881                                 visLoc := strWidth
882                                 remainder := tabSize - (visLoc % tabSize)
883                                 for i := 0; i < remainder-1; i++ {
884                                         screenX++
885                                         if screenX-v.x-v.leftCol >= v.lineNumOffset {
886                                                 v.drawCell(screenX-v.leftCol, screenY, ' ', nil, lineStyle)
887                                         }
888                                 }
889                                 strWidth += remainder
890                         } else if runewidth.RuneWidth(ch) > 1 {
891                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
892                                         v.drawCell(screenX, screenY, ch, nil, lineStyle)
893                                 }
894                                 for i := 0; i < runewidth.RuneWidth(ch)-1; i++ {
895                                         screenX++
896                                         if screenX-v.x-v.leftCol >= v.lineNumOffset {
897                                                 v.drawCell(screenX-v.leftCol, screenY, '<', nil, lineStyle)
898                                         }
899                                 }
900                                 strWidth += StringWidth(string(ch), tabSize)
901                         } else {
902                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
903                                         v.drawCell(screenX-v.leftCol, screenY, ch, nil, lineStyle)
904                                 }
905                                 strWidth += StringWidth(string(ch), tabSize)
906                         }
907                         charNum = charNum.Move(1, v.Buf)
908                         screenX++
909                         colN++
910                 }
911                 // Here we are at a newline
912
913                 if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN && colN == v.Cursor.X {
914                         v.DisplayCursor(screenX-v.leftCol, screenY)
915                 }
916
917                 // The newline may be selected, in which case we should draw the selection style
918                 // with a space to represent it
919                 if v.Cursor.HasSelection() &&
920                         (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
921                                 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
922
923                         selectStyle := defStyle.Reverse(true)
924
925                         if style, ok := colorscheme["selection"]; ok {
926                                 selectStyle = style
927                         }
928                         v.drawCell(screenX, screenY, ' ', nil, selectStyle)
929                         screenX++
930                 }
931
932                 charNum = charNum.Move(1, v.Buf)
933
934                 for i := 0; i < v.Width; i++ {
935                         lineStyle := defStyle
936                         if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
937                                 if style, ok := colorscheme["cursor-line"]; ok {
938                                         fg, _, _ := style.Decompose()
939                                         lineStyle = lineStyle.Background(fg)
940                                 }
941                         }
942                         if screenX-v.x-v.leftCol+i >= v.lineNumOffset {
943                                 colorcolumn := int(v.Buf.Settings["colorcolumn"].(float64))
944                                 if colorcolumn != 0 && screenX-v.lineNumOffset+i == colorcolumn-1 {
945                                         if style, ok := colorscheme["color-column"]; ok {
946                                                 fg, _, _ := style.Decompose()
947                                                 lineStyle = lineStyle.Background(fg)
948                                         }
949                                 }
950                                 v.drawCell(screenX-v.leftCol+i, screenY, ' ', nil, lineStyle)
951                         }
952                 }
953         }
954 }
955
956 // DisplayCursor draws the current buffer's cursor to the screen
957 func (v *View) DisplayCursor(x, y int) {
958         // screen.ShowCursor(v.x+v.Cursor.GetVisualX()+v.lineNumOffset-v.leftCol, y)
959         screen.ShowCursor(x, y)
960 }
961
962 // Display renders the view, the cursor, and statusline
963 func (v *View) Display() {
964         v.DisplayView()
965         // Don't draw the cursor if it is out of the viewport or if it has a selection
966         if (v.Cursor.Y-v.Topline < 0 || v.Cursor.Y-v.Topline > v.Height-1) || v.Cursor.HasSelection() {
967                 screen.HideCursor()
968         }
969         _, screenH := screen.Size()
970         if v.Buf.Settings["statusline"].(bool) {
971                 v.sline.Display()
972         } else if (v.y + v.Height) != screenH-1 {
973                 for x := 0; x < v.Width; x++ {
974                         screen.SetContent(v.x+x, v.y+v.Height, '-', nil, defStyle.Reverse(true))
975                 }
976         }
977 }