cmd/micro/view.go

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