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                 if vy >= v.Buf.NumLines {
 308                         vy = v.Buf.NumLines - 1
 309                 }
 310                 vx = v.Cursor.GetCharPosInLine(vy, vx)
 311                 return vx, vy
 312         }
 313
 314         screenX, screenY := 0, v.Topline
 315         for lineN := v.Topline; lineN < v.Bottomline(); lineN++ {
 316                 line := v.Buf.Line(lineN)
 317                 if lineN >= v.Buf.NumLines {
 318                         return 0, v.Buf.NumLines - 1
 319                 }
 320
 321                 colN := 0
 322                 for _, ch := range line {
 323                         if screenX >= v.Width-v.lineNumOffset {
 324                                 screenX = 0
 325                                 screenY++
 326                         }
 327
 328                         if screenX == vx && screenY == vy {
 329                                 return colN, lineN
 330                         }
 331
 332                         if ch == '\t' {
 333                                 screenX += int(v.Buf.Settings["tabsize"].(float64)) - 1
 334                         }
 335
 336                         screenX++
 337                         colN++
 338                 }
 339                 if screenY == vy {
 340                         return colN, lineN
 341                 }
 342                 screenX = 0
 343                 screenY++
 344         }
 345
 346         return 0, 0
 347 }
 348
 349 func (v *View) Bottomline() int {
 350         if !v.Buf.Settings["softwrap"].(bool) {
 351                 return v.Topline + v.Height
 352         }
 353
 354         screenX, screenY := 0, 0
 355         numLines := 0
 356         for lineN := v.Topline; lineN < v.Topline+v.Height; lineN++ {
 357                 line := v.Buf.Line(lineN)
 358
 359                 colN := 0
 360                 for _, ch := range line {
 361                         if screenX >= v.Width-v.lineNumOffset {
 362                                 screenX = 0
 363                                 screenY++
 364                         }
 365
 366                         if ch == '\t' {
 367                                 screenX += int(v.Buf.Settings["tabsize"].(float64)) - 1
 368                         }
 369
 370                         screenX++
 371                         colN++
 372                 }
 373                 screenX = 0
 374                 screenY++
 375                 numLines++
 376
 377                 if screenY >= v.Height {
 378                         break
 379                 }
 380         }
 381         return numLines + v.Topline
 382 }
 383
 384 // Relocate moves the view window so that the cursor is in view
 385 // This is useful if the user has scrolled far away, and then starts typing
 386 func (v *View) Relocate() bool {
 387         height := v.Bottomline() - v.Topline
 388         ret := false
 389         cy := v.Cursor.Y
 390         scrollmargin := int(v.Buf.Settings["scrollmargin"].(float64))
 391         if cy < v.Topline+scrollmargin && cy > scrollmargin-1 {
 392                 v.Topline = cy - scrollmargin
 393                 ret = true
 394         } else if cy < v.Topline {
 395                 v.Topline = cy
 396                 ret = true
 397         }
 398         if cy > v.Topline+height-1-scrollmargin && cy < v.Buf.NumLines-scrollmargin {
 399                 v.Topline = cy - height + 1 + scrollmargin
 400                 ret = true
 401         } else if cy >= v.Buf.NumLines-scrollmargin && cy > height {
 402                 v.Topline = v.Buf.NumLines - height
 403                 ret = true
 404         }
 405
 406         if !v.Buf.Settings["softwrap"].(bool) {
 407                 cx := v.Cursor.GetVisualX()
 408                 if cx < v.leftCol {
 409                         v.leftCol = cx
 410                         ret = true
 411                 }
 412                 if cx+v.lineNumOffset+1 > v.leftCol+v.Width {
 413                         v.leftCol = cx - v.Width + v.lineNumOffset + 1
 414                         ret = true
 415                 }
 416         }
 417         return ret
 418 }
 419
 420 // MoveToMouseClick moves the cursor to location x, y assuming x, y were given
 421 // by a mouse click
 422 func (v *View) MoveToMouseClick(x, y int) {
 423         if y-v.Topline > v.Height-1 {
 424                 v.ScrollDown(1)
 425                 y = v.Height + v.Topline - 1
 426         }
 427         if y < 0 {
 428                 y = 0
 429         }
 430         if x < 0 {
 431                 x = 0
 432         }
 433
 434         x, y = v.GetSoftWrapLocation(x, y)
 435         // x = v.Cursor.GetCharPosInLine(y, x)
 436         if x > Count(v.Buf.Line(y)) {
 437                 x = Count(v.Buf.Line(y))
 438         }
 439         v.Cursor.X = x
 440         v.Cursor.Y = y
 441         v.Cursor.LastVisualX = v.Cursor.GetVisualX()
 442 }
 443
 444 // HandleEvent handles an event passed by the main loop
 445 func (v *View) HandleEvent(event tcell.Event) {
 446         // This bool determines whether the view is relocated at the end of the function
 447         // By default it's true because most events should cause a relocate
 448         relocate := true
 449
 450         v.Buf.CheckModTime()
 451
 452         switch e := event.(type) {
 453         case *tcell.EventKey:
 454                 // Check first if input is a key binding, if it is we 'eat' the input and don't insert a rune
 455                 isBinding := false
 456                 if e.Key() != tcell.KeyRune || e.Modifiers() != 0 {
 457                         for key, actions := range bindings {
 458                                 if e.Key() == key.keyCode {
 459                                         if e.Key() == tcell.KeyRune {
 460                                                 if e.Rune() != key.r {
 461                                                         continue
 462                                                 }
 463                                         }
 464                                         if e.Modifiers() == key.modifiers {
 465                                                 relocate = false
 466                                                 isBinding = true
 467                                                 for _, action := range actions {
 468                                                         relocate = action(v, true) || relocate
 469                                                         funcName := FuncName(action)
 470                                                         if funcName != "main.(*View).ToggleMacro" && funcName != "main.(*View).PlayMacro" {
 471                                                                 if recordingMacro {
 472                                                                         curMacro = append(curMacro, action)
 473                                                                 }
 474                                                         }
 475                                                 }
 476                                                 break
 477                                         }
 478                                 }
 479                         }
 480                 }
 481                 if !isBinding && e.Key() == tcell.KeyRune {
 482                         // Insert a character
 483                         if v.Cursor.HasSelection() {
 484                                 v.Cursor.DeleteSelection()
 485                                 v.Cursor.ResetSelection()
 486                         }
 487                         v.Buf.Insert(v.Cursor.Loc, string(e.Rune()))
 488                         v.Cursor.Right()
 489
 490                         for pl := range loadedPlugins {
 491                                 _, err := Call(pl+".onRune", string(e.Rune()), v)
 492                                 if err != nil && !strings.HasPrefix(err.Error(), "function does not exist") {
 493                                         TermMessage(err)
 494                                 }
 495                         }
 496
 497                         if recordingMacro {
 498                                 curMacro = append(curMacro, e.Rune())
 499                         }
 500                 }
 501         case *tcell.EventPaste:
 502                 if !PreActionCall("Paste", v) {
 503                         break
 504                 }
 505
 506                 v.paste(e.Text())
 507
 508                 PostActionCall("Paste", v)
 509         case *tcell.EventMouse:
 510                 x, y := e.Position()
 511                 x -= v.lineNumOffset - v.leftCol + v.x
 512                 y += v.Topline - v.y
 513                 // Don't relocate for mouse events
 514                 relocate = false
 515
 516                 button := e.Buttons()
 517
 518                 switch button {
 519                 case tcell.Button1:
 520                         // Left click
 521                         if v.mouseReleased {
 522                                 v.MoveToMouseClick(x, y)
 523                                 if time.Since(v.lastClickTime)/time.Millisecond < doubleClickThreshold {
 524                                         if v.doubleClick {
 525                                                 // Triple click
 526                                                 v.lastClickTime = time.Now()
 527
 528                                                 v.tripleClick = true
 529                                                 v.doubleClick = false
 530
 531                                                 v.Cursor.SelectLine()
 532                                                 v.Cursor.CopySelection("primary")
 533                                         } else {
 534                                                 // Double click
 535                                                 v.lastClickTime = time.Now()
 536
 537                                                 v.doubleClick = true
 538                                                 v.tripleClick = false
 539
 540                                                 v.Cursor.SelectWord()
 541                                                 v.Cursor.CopySelection("primary")
 542                                         }
 543                                 } else {
 544                                         v.doubleClick = false
 545                                         v.tripleClick = false
 546                                         v.lastClickTime = time.Now()
 547
 548                                         v.Cursor.OrigSelection[0] = v.Cursor.Loc
 549                                         v.Cursor.CurSelection[0] = v.Cursor.Loc
 550                                         v.Cursor.CurSelection[1] = v.Cursor.Loc
 551                                 }
 552                                 v.mouseReleased = false
 553                         } else if !v.mouseReleased {
 554                                 v.MoveToMouseClick(x, y)
 555                                 if v.tripleClick {
 556                                         v.Cursor.AddLineToSelection()
 557                                 } else if v.doubleClick {
 558                                         v.Cursor.AddWordToSelection()
 559                                 } else {
 560                                         v.Cursor.SetSelectionEnd(v.Cursor.Loc)
 561                                         v.Cursor.CopySelection("primary")
 562                                 }
 563                         }
 564                 case tcell.Button2:
 565                         // Middle mouse button was clicked,
 566                         // We should paste primary
 567                         v.PastePrimary(true)
 568                 case tcell.ButtonNone:
 569                         // Mouse event with no click
 570                         if !v.mouseReleased {
 571                                 // Mouse was just released
 572
 573                                 // Relocating here isn't really necessary because the cursor will
 574                                 // be in the right place from the last mouse event
 575                                 // However, if we are running in a terminal that doesn't support mouse motion
 576                                 // events, this still allows the user to make selections, except only after they
 577                                 // release the mouse
 578
 579                                 if !v.doubleClick && !v.tripleClick {
 580                                         v.MoveToMouseClick(x, y)
 581                                         v.Cursor.SetSelectionEnd(v.Cursor.Loc)
 582                                         v.Cursor.CopySelection("primary")
 583                                 }
 584                                 v.mouseReleased = true
 585                         }
 586                 case tcell.WheelUp:
 587                         // Scroll up
 588                         scrollspeed := int(v.Buf.Settings["scrollspeed"].(float64))
 589                         v.ScrollUp(scrollspeed)
 590                 case tcell.WheelDown:
 591                         // Scroll down
 592                         scrollspeed := int(v.Buf.Settings["scrollspeed"].(float64))
 593                         v.ScrollDown(scrollspeed)
 594                 }
 595         }
 596
 597         if relocate {
 598                 v.Relocate()
 599         }
 600 }
 601
 602 // GutterMessage creates a message in this view's gutter
 603 func (v *View) GutterMessage(section string, lineN int, msg string, kind int) {
 604         lineN--
 605         gutterMsg := GutterMessage{
 606                 lineNum: lineN,
 607                 msg:     msg,
 608                 kind:    kind,
 609         }
 610         for _, v := range v.messages {
 611                 for _, gmsg := range v {
 612                         if gmsg.lineNum == lineN {
 613                                 return
 614                         }
 615                 }
 616         }
 617         messages := v.messages[section]
 618         v.messages[section] = append(messages, gutterMsg)
 619 }
 620
 621 // ClearGutterMessages clears all gutter messages from a given section
 622 func (v *View) ClearGutterMessages(section string) {
 623         v.messages[section] = []GutterMessage{}
 624 }
 625
 626 // ClearAllGutterMessages clears all the gutter messages
 627 func (v *View) ClearAllGutterMessages() {
 628         for k := range v.messages {
 629                 v.messages[k] = []GutterMessage{}
 630         }
 631 }
 632
 633 // Opens the given help page in a new horizontal split
 634 func (v *View) openHelp(helpPage string) {
 635         if data, err := FindRuntimeFile(RTHelp, helpPage).Data(); err != nil {
 636                 TermMessage("Unable to load help text", helpPage, "\n", err)
 637         } else {
 638                 helpBuffer := NewBuffer(strings.NewReader(string(data)), helpPage+".md")
 639                 helpBuffer.name = "Help"
 640
 641                 if v.Type == vtHelp {
 642                         v.OpenBuffer(helpBuffer)
 643                 } else {
 644                         v.HSplit(helpBuffer)
 645                         CurView().Type = vtHelp
 646                 }
 647         }
 648 }
 649
 650 func (v *View) drawCell(x, y int, ch rune, combc []rune, style tcell.Style) {
 651         if x >= v.x && x < v.x+v.Width && y >= v.y && y < v.y+v.Height {
 652                 screen.SetContent(x, y, ch, combc, style)
 653         }
 654 }
 655
 656 // DisplayView renders the view to the screen
 657 func (v *View) DisplayView() {
 658         if v.Type == vtLog {
 659                 // Log views should always follow the cursor...
 660                 v.Relocate()
 661         }
 662
 663         if v.Buf.Settings["syntax"].(bool) {
 664                 v.matches = Match(v)
 665         }
 666
 667         // The charNum we are currently displaying
 668         // starts at the start of the viewport
 669         charNum := Loc{0, v.Topline}
 670
 671         // Convert the length of buffer to a string, and get the length of the string
 672         // We are going to have to offset by that amount
 673         maxLineLength := len(strconv.Itoa(v.Buf.NumLines))
 674
 675         if v.Buf.Settings["ruler"] == true {
 676                 // + 1 for the little space after the line number
 677                 v.lineNumOffset = maxLineLength + 1
 678         } else {
 679                 v.lineNumOffset = 0
 680         }
 681
 682         // We need to add to the line offset if there are gutter messages
 683         var hasGutterMessages bool
 684         for _, v := range v.messages {
 685                 if len(v) > 0 {
 686                         hasGutterMessages = true
 687                 }
 688         }
 689         if hasGutterMessages {
 690                 v.lineNumOffset += 2
 691         }
 692
 693         if v.x != 0 {
 694                 // One space for the extra split divider
 695                 v.lineNumOffset++
 696         }
 697
 698         // These represent the current screen coordinates
 699         screenX, screenY := v.x, v.y-1
 700
 701         highlightStyle := defStyle
 702         curLineN := 0
 703
 704         // ViewLine is the current line from the top of the viewport
 705         for viewLine := 0; viewLine < v.Height; viewLine++ {
 706                 screenY++
 707                 screenX = v.x
 708
 709                 // This is the current line number of the buffer that we are drawing
 710                 curLineN = viewLine + v.Topline
 711
 712                 if screenY-v.y >= v.Height {
 713                         break
 714                 }
 715
 716                 if v.x != 0 {
 717                         dividerStyle := defStyle
 718                                         if style, ok := colorscheme["divider"]; ok {
 719                                                         dividerStyle = style
 720                                         }
 721                         // Draw the split divider
 722                         v.drawCell(screenX, screenY, tcell.RuneVLine, nil, dividerStyle)
 723                         screenX++
 724                 }
 725
 726                 // If the buffer is smaller than the view height we have to clear all this space
 727                 if curLineN >= v.Buf.NumLines {
 728                         for i := screenX; i < v.x+v.Width; i++ {
 729                                 v.drawCell(i, screenY, ' ', nil, defStyle)
 730                         }
 731
 732                         continue
 733                 }
 734                 line := v.Buf.Line(curLineN)
 735
 736                 // If there are gutter messages we need to display the '>>' symbol here
 737                 if hasGutterMessages {
 738                         // msgOnLine stores whether or not there is a gutter message on this line in particular
 739                         msgOnLine := false
 740                         for k := range v.messages {
 741                                 for _, msg := range v.messages[k] {
 742                                         if msg.lineNum == curLineN {
 743                                                 msgOnLine = true
 744                                                 gutterStyle := defStyle
 745                                                 switch msg.kind {
 746                                                 case GutterInfo:
 747                                                         if style, ok := colorscheme["gutter-info"]; ok {
 748                                                                 gutterStyle = style
 749                                                         }
 750                                                 case GutterWarning:
 751                                                         if style, ok := colorscheme["gutter-warning"]; ok {
 752                                                                 gutterStyle = style
 753                                                         }
 754                                                 case GutterError:
 755                                                         if style, ok := colorscheme["gutter-error"]; ok {
 756                                                                 gutterStyle = style
 757                                                         }
 758                                                 }
 759                                                 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
 760                                                 screenX++
 761                                                 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
 762                                                 screenX++
 763                                                 if v.Cursor.Y == curLineN && !messenger.hasPrompt {
 764                                                         messenger.Message(msg.msg)
 765                                                         messenger.gutterMessage = true
 766                                                 }
 767                                         }
 768                                 }
 769                         }
 770                         // If there is no message on this line we just display an empty offset
 771                         if !msgOnLine {
 772                                 v.drawCell(screenX, screenY, ' ', nil, defStyle)
 773                                 screenX++
 774                                 v.drawCell(screenX, screenY, ' ', nil, defStyle)
 775                                 screenX++
 776                                 if v.Cursor.Y == curLineN && messenger.gutterMessage {
 777                                         messenger.Reset()
 778                                         messenger.gutterMessage = false
 779                                 }
 780                         }
 781                 }
 782
 783                 lineNumStyle := defStyle
 784                 if v.Buf.Settings["ruler"] == true {
 785                         // Write the line number
 786                         if style, ok := colorscheme["line-number"]; ok {
 787                                 lineNumStyle = style
 788                         }
 789                         if style, ok := colorscheme["current-line-number"]; ok {
 790                                 if curLineN == v.Cursor.Y && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() {
 791                                         lineNumStyle = style
 792                                 }
 793                         }
 794
 795                         lineNum := strconv.Itoa(curLineN + 1)
 796
 797                         // Write the spaces before the line number if necessary
 798                         for i := 0; i < maxLineLength-len(lineNum); i++ {
 799                                 v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
 800                                 screenX++
 801                         }
 802                         // Write the actual line number
 803                         for _, ch := range lineNum {
 804                                 v.drawCell(screenX, screenY, ch, nil, lineNumStyle)
 805                                 screenX++
 806                         }
 807
 808                         // Write the extra space
 809                         v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
 810                         screenX++
 811                 }
 812
 813                 // Now we actually draw the line
 814                 colN := 0
 815                 strWidth := 0
 816                 tabSize := int(v.Buf.Settings["tabsize"].(float64))
 817                 for _, ch := range line {
 818                         if v.Buf.Settings["softwrap"].(bool) {
 819                                 if screenX-v.x >= v.Width {
 820                                         screenY++
 821
 822                                         x := 0
 823                                         if hasGutterMessages {
 824                                                 v.drawCell(v.x+x, screenY, ' ', nil, defStyle)
 825                                                 x++
 826                                                 v.drawCell(v.x+x, screenY, ' ', nil, defStyle)
 827                                                 x++
 828                                         }
 829                                         for i := 0; i < v.lineNumOffset; i++ {
 830                                                 screen.SetContent(v.x+i+x, screenY, ' ', nil, lineNumStyle)
 831                                         }
 832                                         screenX = v.x + v.lineNumOffset
 833                                 }
 834                         }
 835
 836                         if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN && colN == v.Cursor.X {
 837                                 v.DisplayCursor(screenX-v.leftCol, screenY)
 838                         }
 839
 840                         lineStyle := defStyle
 841
 842                         if v.Buf.Settings["syntax"].(bool) {
 843                                 // Syntax highlighting is enabled
 844                                 highlightStyle = v.matches[viewLine][colN]
 845                         }
 846
 847                         if v.Cursor.HasSelection() &&
 848                                 (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
 849                                         charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
 850                                 // The current character is selected
 851                                 lineStyle = defStyle.Reverse(true)
 852
 853                                 if style, ok := colorscheme["selection"]; ok {
 854                                         lineStyle = style
 855                                 }
 856                         } else {
 857                                 lineStyle = highlightStyle
 858                         }
 859
 860                         // We need to display the background of the linestyle with the correct color if cursorline is enabled
 861                         // and this is the current view and there is no selection on this line and the cursor is on this line
 862                         if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
 863                                 if style, ok := colorscheme["cursor-line"]; ok {
 864                                         fg, _, _ := style.Decompose()
 865                                         lineStyle = lineStyle.Background(fg)
 866                                 }
 867                         }
 868
 869                         if ch == '\t' {
 870                                 // If the character we are displaying is a tab, we need to do a bunch of special things
 871
 872                                 // First the user may have configured an `indent-char` to be displayed to show that this
 873                                 // is a tab character
 874                                 lineIndentStyle := defStyle
 875                                 if style, ok := colorscheme["indent-char"]; ok && v.Buf.Settings["indentchar"].(string) != " " {
 876                                         lineIndentStyle = style
 877                                 }
 878                                 if v.Cursor.HasSelection() &&
 879                                         (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
 880                                                 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
 881
 882                                         lineIndentStyle = defStyle.Reverse(true)
 883
 884                                         if style, ok := colorscheme["selection"]; ok {
 885                                                 lineIndentStyle = style
 886                                         }
 887                                 }
 888                                 if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
 889                                         if style, ok := colorscheme["cursor-line"]; ok {
 890                                                 fg, _, _ := style.Decompose()
 891                                                 lineIndentStyle = lineIndentStyle.Background(fg)
 892                                         }
 893                                 }
 894                                 // Here we get the indent char
 895                                 indentChar := []rune(v.Buf.Settings["indentchar"].(string))
 896                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
 897                                         v.drawCell(screenX-v.leftCol, screenY, indentChar[0], nil, lineIndentStyle)
 898                                 }
 899                                 // Now the tab has to be displayed as a bunch of spaces
 900                                 visLoc := strWidth
 901                                 remainder := tabSize - (visLoc % tabSize)
 902                                 for i := 0; i < remainder-1; i++ {
 903                                         screenX++
 904                                         if screenX-v.x-v.leftCol >= v.lineNumOffset {
 905                                                 v.drawCell(screenX-v.leftCol, screenY, ' ', nil, lineStyle)
 906                                         }
 907                                 }
 908                                 strWidth += remainder
 909                         } else if runewidth.RuneWidth(ch) > 1 {
 910                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
 911                                         v.drawCell(screenX, screenY, ch, nil, lineStyle)
 912                                 }
 913                                 for i := 0; i < runewidth.RuneWidth(ch)-1; i++ {
 914                                         screenX++
 915                                         if screenX-v.x-v.leftCol >= v.lineNumOffset {
 916                                                 v.drawCell(screenX-v.leftCol, screenY, '<', nil, lineStyle)
 917                                         }
 918                                 }
 919                                 strWidth += StringWidth(string(ch), tabSize)
 920                         } else {
 921                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
 922                                         v.drawCell(screenX-v.leftCol, screenY, ch, nil, lineStyle)
 923                                 }
 924                                 strWidth += StringWidth(string(ch), tabSize)
 925                         }
 926                         charNum = charNum.Move(1, v.Buf)
 927                         screenX++
 928                         colN++
 929                 }
 930                 // Here we are at a newline
 931
 932                 if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN && colN == v.Cursor.X {
 933                         v.DisplayCursor(screenX-v.leftCol, screenY)
 934                 }
 935
 936                 // The newline may be selected, in which case we should draw the selection style
 937                 // with a space to represent it
 938                 if v.Cursor.HasSelection() &&
 939                         (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
 940                                 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
 941
 942                         selectStyle := defStyle.Reverse(true)
 943
 944                         if style, ok := colorscheme["selection"]; ok {
 945                                 selectStyle = style
 946                         }
 947                         v.drawCell(screenX, screenY, ' ', nil, selectStyle)
 948                         screenX++
 949                 }
 950
 951                 charNum = charNum.Move(1, v.Buf)
 952
 953                 for i := 0; i < v.Width; i++ {
 954                         lineStyle := defStyle
 955                         if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
 956                                 if style, ok := colorscheme["cursor-line"]; ok {
 957                                         fg, _, _ := style.Decompose()
 958                                         lineStyle = lineStyle.Background(fg)
 959                                 }
 960                         }
 961                         if screenX-v.x-v.leftCol+i >= v.lineNumOffset {
 962                                 colorcolumn := int(v.Buf.Settings["colorcolumn"].(float64))
 963                                 if colorcolumn != 0 && screenX-v.lineNumOffset+i == colorcolumn-1 {
 964                                         if style, ok := colorscheme["color-column"]; ok {
 965                                                 fg, _, _ := style.Decompose()
 966                                                 lineStyle = lineStyle.Background(fg)
 967                                         }
 968                                 }
 969                                 v.drawCell(screenX-v.leftCol+i, screenY, ' ', nil, lineStyle)
 970                         }
 971                 }
 972         }
 973 }
 974
 975 // DisplayCursor draws the current buffer's cursor to the screen
 976 func (v *View) DisplayCursor(x, y int) {
 977         // screen.ShowCursor(v.x+v.Cursor.GetVisualX()+v.lineNumOffset-v.leftCol, y)
 978         screen.ShowCursor(x, y)
 979 }
 980
 981 // Display renders the view, the cursor, and statusline
 982 func (v *View) Display() {
 983         v.DisplayView()
 984         // Don't draw the cursor if it is out of the viewport or if it has a selection
 985         if (v.Cursor.Y-v.Topline < 0 || v.Cursor.Y-v.Topline > v.Height-1) || v.Cursor.HasSelection() {
 986                 screen.HideCursor()
 987         }
 988         _, screenH := screen.Size()
 989         if v.Buf.Settings["statusline"].(bool) {
 990                 v.sline.Display()
 991         } else if (v.y + v.Height) != screenH-1 {
 992                 for x := 0; x < v.Width; x++ {
 993                         screen.SetContent(v.x+x, v.y+v.Height, '-', nil, defStyle.Reverse(true))
 994                 }
 995         }
 996 }