cmd/micro/view.go

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