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         fileInfo, _ := os.Stat(filename)
 247
 248         if err == nil && fileInfo.IsDir() {
 249                 messenger.Error(filename, " is a directory")
 250                 return
 251         }
 252
 253         defer file.Close()
 254
 255         var buf *Buffer
 256         if err != nil {
 257                 messenger.Message(err.Error())
 258                 // File does not exist -- create an empty buffer with that name
 259                 buf = NewBuffer(strings.NewReader(""), filename)
 260         } else {
 261                 buf = NewBuffer(file, filename)
 262         }
 263         v.OpenBuffer(buf)
 264 }
 265
 266 // CloseBuffer performs any closing functions on the buffer
 267 func (v *View) CloseBuffer() {
 268         if v.Buf != nil {
 269                 v.Buf.Serialize()
 270         }
 271 }
 272
 273 // ReOpen reloads the current buffer
 274 func (v *View) ReOpen() {
 275         if v.CanClose() {
 276                 screen.Clear()
 277                 v.Buf.ReOpen()
 278                 v.Relocate()
 279                 v.matches = Match(v)
 280         }
 281 }
 282
 283 // HSplit opens a horizontal split with the given buffer
 284 func (v *View) HSplit(buf *Buffer) {
 285         i := 0
 286         if v.Buf.Settings["splitBottom"].(bool) {
 287                 i = 1
 288         }
 289         v.splitNode.HSplit(buf, v.Num+i)
 290 }
 291
 292 // VSplit opens a vertical split with the given buffer
 293 func (v *View) VSplit(buf *Buffer) {
 294         i := 0
 295         if v.Buf.Settings["splitRight"].(bool) {
 296                 i = 1
 297         }
 298         v.splitNode.VSplit(buf, v.Num+i)
 299 }
 300
 301 // HSplitIndex opens a horizontal split with the given buffer at the given index
 302 func (v *View) HSplitIndex(buf *Buffer, splitIndex int) {
 303         v.splitNode.HSplit(buf, splitIndex)
 304 }
 305
 306 // VSplitIndex opens a vertical split with the given buffer at the given index
 307 func (v *View) VSplitIndex(buf *Buffer, splitIndex int) {
 308         v.splitNode.VSplit(buf, splitIndex)
 309 }
 310
 311 // GetSoftWrapLocation gets the location of a visual click on the screen and converts it to col,line
 312 func (v *View) GetSoftWrapLocation(vx, vy int) (int, int) {
 313         if !v.Buf.Settings["softwrap"].(bool) {
 314                 if vy >= v.Buf.NumLines {
 315                         vy = v.Buf.NumLines - 1
 316                 }
 317                 vx = v.Cursor.GetCharPosInLine(vy, vx)
 318                 return vx, vy
 319         }
 320
 321         screenX, screenY := 0, v.Topline
 322         for lineN := v.Topline; lineN < v.Bottomline(); lineN++ {
 323                 line := v.Buf.Line(lineN)
 324                 if lineN >= v.Buf.NumLines {
 325                         return 0, v.Buf.NumLines - 1
 326                 }
 327
 328                 colN := 0
 329                 for _, ch := range line {
 330                         if screenX >= v.Width-v.lineNumOffset {
 331                                 screenX = 0
 332                                 screenY++
 333                         }
 334
 335                         if screenX == vx && screenY == vy {
 336                                 return colN, lineN
 337                         }
 338
 339                         if ch == '\t' {
 340                                 screenX += int(v.Buf.Settings["tabsize"].(float64)) - 1
 341                         }
 342
 343                         screenX++
 344                         colN++
 345                 }
 346                 if screenY == vy {
 347                         return colN, lineN
 348                 }
 349                 screenX = 0
 350                 screenY++
 351         }
 352
 353         return 0, 0
 354 }
 355
 356 func (v *View) Bottomline() int {
 357         if !v.Buf.Settings["softwrap"].(bool) {
 358                 return v.Topline + v.Height
 359         }
 360
 361         screenX, screenY := 0, 0
 362         numLines := 0
 363         for lineN := v.Topline; lineN < v.Topline+v.Height; lineN++ {
 364                 line := v.Buf.Line(lineN)
 365
 366                 colN := 0
 367                 for _, ch := range line {
 368                         if screenX >= v.Width-v.lineNumOffset {
 369                                 screenX = 0
 370                                 screenY++
 371                         }
 372
 373                         if ch == '\t' {
 374                                 screenX += int(v.Buf.Settings["tabsize"].(float64)) - 1
 375                         }
 376
 377                         screenX++
 378                         colN++
 379                 }
 380                 screenX = 0
 381                 screenY++
 382                 numLines++
 383
 384                 if screenY >= v.Height {
 385                         break
 386                 }
 387         }
 388         return numLines + v.Topline
 389 }
 390
 391 // Relocate moves the view window so that the cursor is in view
 392 // This is useful if the user has scrolled far away, and then starts typing
 393 func (v *View) Relocate() bool {
 394         height := v.Bottomline() - v.Topline
 395         ret := false
 396         cy := v.Cursor.Y
 397         scrollmargin := int(v.Buf.Settings["scrollmargin"].(float64))
 398         if cy < v.Topline+scrollmargin && cy > scrollmargin-1 {
 399                 v.Topline = cy - scrollmargin
 400                 ret = true
 401         } else if cy < v.Topline {
 402                 v.Topline = cy
 403                 ret = true
 404         }
 405         if cy > v.Topline+height-1-scrollmargin && cy < v.Buf.NumLines-scrollmargin {
 406                 v.Topline = cy - height + 1 + scrollmargin
 407                 ret = true
 408         } else if cy >= v.Buf.NumLines-scrollmargin && cy > height {
 409                 v.Topline = v.Buf.NumLines - height
 410                 ret = true
 411         }
 412
 413         if !v.Buf.Settings["softwrap"].(bool) {
 414                 cx := v.Cursor.GetVisualX()
 415                 if cx < v.leftCol {
 416                         v.leftCol = cx
 417                         ret = true
 418                 }
 419                 if cx+v.lineNumOffset+1 > v.leftCol+v.Width {
 420                         v.leftCol = cx - v.Width + v.lineNumOffset + 1
 421                         ret = true
 422                 }
 423         }
 424         return ret
 425 }
 426
 427 // MoveToMouseClick moves the cursor to location x, y assuming x, y were given
 428 // by a mouse click
 429 func (v *View) MoveToMouseClick(x, y int) {
 430         if y-v.Topline > v.Height-1 {
 431                 v.ScrollDown(1)
 432                 y = v.Height + v.Topline - 1
 433         }
 434         if y < 0 {
 435                 y = 0
 436         }
 437         if x < 0 {
 438                 x = 0
 439         }
 440
 441         x, y = v.GetSoftWrapLocation(x, y)
 442         // x = v.Cursor.GetCharPosInLine(y, x)
 443         if x > Count(v.Buf.Line(y)) {
 444                 x = Count(v.Buf.Line(y))
 445         }
 446         v.Cursor.X = x
 447         v.Cursor.Y = y
 448         v.Cursor.LastVisualX = v.Cursor.GetVisualX()
 449 }
 450
 451 // HandleEvent handles an event passed by the main loop
 452 func (v *View) HandleEvent(event tcell.Event) {
 453         // This bool determines whether the view is relocated at the end of the function
 454         // By default it's true because most events should cause a relocate
 455         relocate := true
 456
 457         v.Buf.CheckModTime()
 458
 459         switch e := event.(type) {
 460         case *tcell.EventKey:
 461                 // Check first if input is a key binding, if it is we 'eat' the input and don't insert a rune
 462                 isBinding := false
 463                 if e.Key() != tcell.KeyRune || e.Modifiers() != 0 {
 464                         for key, actions := range bindings {
 465                                 if e.Key() == key.keyCode {
 466                                         if e.Key() == tcell.KeyRune {
 467                                                 if e.Rune() != key.r {
 468                                                         continue
 469                                                 }
 470                                         }
 471                                         if e.Modifiers() == key.modifiers {
 472                                                 relocate = false
 473                                                 isBinding = true
 474                                                 for _, action := range actions {
 475                                                         relocate = action(v, true) || relocate
 476                                                         funcName := FuncName(action)
 477                                                         if funcName != "main.(*View).ToggleMacro" && funcName != "main.(*View).PlayMacro" {
 478                                                                 if recordingMacro {
 479                                                                         curMacro = append(curMacro, action)
 480                                                                 }
 481                                                         }
 482                                                 }
 483                                                 break
 484                                         }
 485                                 }
 486                         }
 487                 }
 488                 if !isBinding && e.Key() == tcell.KeyRune {
 489                         // Insert a character
 490                         if v.Cursor.HasSelection() {
 491                                 v.Cursor.DeleteSelection()
 492                                 v.Cursor.ResetSelection()
 493                         }
 494                         v.Buf.Insert(v.Cursor.Loc, string(e.Rune()))
 495                         v.Cursor.Right()
 496
 497                         for pl := range loadedPlugins {
 498                                 _, err := Call(pl+".onRune", string(e.Rune()), v)
 499                                 if err != nil && !strings.HasPrefix(err.Error(), "function does not exist") {
 500                                         TermMessage(err)
 501                                 }
 502                         }
 503
 504                         if recordingMacro {
 505                                 curMacro = append(curMacro, e.Rune())
 506                         }
 507                 }
 508         case *tcell.EventPaste:
 509                 if !PreActionCall("Paste", v) {
 510                         break
 511                 }
 512
 513                 v.paste(e.Text())
 514
 515                 PostActionCall("Paste", v)
 516         case *tcell.EventMouse:
 517                 x, y := e.Position()
 518                 x -= v.lineNumOffset - v.leftCol + v.x
 519                 y += v.Topline - v.y
 520                 // Don't relocate for mouse events
 521                 relocate = false
 522
 523                 button := e.Buttons()
 524
 525                 switch button {
 526                 case tcell.Button1:
 527                         // Left click
 528                         if v.mouseReleased {
 529                                 v.MoveToMouseClick(x, y)
 530                                 if time.Since(v.lastClickTime)/time.Millisecond < doubleClickThreshold {
 531                                         if v.doubleClick {
 532                                                 // Triple click
 533                                                 v.lastClickTime = time.Now()
 534
 535                                                 v.tripleClick = true
 536                                                 v.doubleClick = false
 537
 538                                                 v.Cursor.SelectLine()
 539                                                 v.Cursor.CopySelection("primary")
 540                                         } else {
 541                                                 // Double click
 542                                                 v.lastClickTime = time.Now()
 543
 544                                                 v.doubleClick = true
 545                                                 v.tripleClick = false
 546
 547                                                 v.Cursor.SelectWord()
 548                                                 v.Cursor.CopySelection("primary")
 549                                         }
 550                                 } else {
 551                                         v.doubleClick = false
 552                                         v.tripleClick = false
 553                                         v.lastClickTime = time.Now()
 554
 555                                         v.Cursor.OrigSelection[0] = v.Cursor.Loc
 556                                         v.Cursor.CurSelection[0] = v.Cursor.Loc
 557                                         v.Cursor.CurSelection[1] = v.Cursor.Loc
 558                                 }
 559                                 v.mouseReleased = false
 560                         } else if !v.mouseReleased {
 561                                 v.MoveToMouseClick(x, y)
 562                                 if v.tripleClick {
 563                                         v.Cursor.AddLineToSelection()
 564                                 } else if v.doubleClick {
 565                                         v.Cursor.AddWordToSelection()
 566                                 } else {
 567                                         v.Cursor.SetSelectionEnd(v.Cursor.Loc)
 568                                         v.Cursor.CopySelection("primary")
 569                                 }
 570                         }
 571                 case tcell.Button2:
 572                         // Middle mouse button was clicked,
 573                         // We should paste primary
 574                         v.PastePrimary(true)
 575                 case tcell.ButtonNone:
 576                         // Mouse event with no click
 577                         if !v.mouseReleased {
 578                                 // Mouse was just released
 579
 580                                 // Relocating here isn't really necessary because the cursor will
 581                                 // be in the right place from the last mouse event
 582                                 // However, if we are running in a terminal that doesn't support mouse motion
 583                                 // events, this still allows the user to make selections, except only after they
 584                                 // release the mouse
 585
 586                                 if !v.doubleClick && !v.tripleClick {
 587                                         v.MoveToMouseClick(x, y)
 588                                         v.Cursor.SetSelectionEnd(v.Cursor.Loc)
 589                                         v.Cursor.CopySelection("primary")
 590                                 }
 591                                 v.mouseReleased = true
 592                         }
 593                 case tcell.WheelUp:
 594                         // Scroll up
 595                         scrollspeed := int(v.Buf.Settings["scrollspeed"].(float64))
 596                         v.ScrollUp(scrollspeed)
 597                 case tcell.WheelDown:
 598                         // Scroll down
 599                         scrollspeed := int(v.Buf.Settings["scrollspeed"].(float64))
 600                         v.ScrollDown(scrollspeed)
 601                 }
 602         }
 603
 604         if relocate {
 605                 v.Relocate()
 606         }
 607 }
 608
 609 // GutterMessage creates a message in this view's gutter
 610 func (v *View) GutterMessage(section string, lineN int, msg string, kind int) {
 611         lineN--
 612         gutterMsg := GutterMessage{
 613                 lineNum: lineN,
 614                 msg:     msg,
 615                 kind:    kind,
 616         }
 617         for _, v := range v.messages {
 618                 for _, gmsg := range v {
 619                         if gmsg.lineNum == lineN {
 620                                 return
 621                         }
 622                 }
 623         }
 624         messages := v.messages[section]
 625         v.messages[section] = append(messages, gutterMsg)
 626 }
 627
 628 // ClearGutterMessages clears all gutter messages from a given section
 629 func (v *View) ClearGutterMessages(section string) {
 630         v.messages[section] = []GutterMessage{}
 631 }
 632
 633 // ClearAllGutterMessages clears all the gutter messages
 634 func (v *View) ClearAllGutterMessages() {
 635         for k := range v.messages {
 636                 v.messages[k] = []GutterMessage{}
 637         }
 638 }
 639
 640 // Opens the given help page in a new horizontal split
 641 func (v *View) openHelp(helpPage string) {
 642         if data, err := FindRuntimeFile(RTHelp, helpPage).Data(); err != nil {
 643                 TermMessage("Unable to load help text", helpPage, "\n", err)
 644         } else {
 645                 helpBuffer := NewBuffer(strings.NewReader(string(data)), helpPage+".md")
 646                 helpBuffer.name = "Help"
 647
 648                 if v.Type == vtHelp {
 649                         v.OpenBuffer(helpBuffer)
 650                 } else {
 651                         v.HSplit(helpBuffer)
 652                         CurView().Type = vtHelp
 653                 }
 654         }
 655 }
 656
 657 func (v *View) drawCell(x, y int, ch rune, combc []rune, style tcell.Style) {
 658         if x >= v.x && x < v.x+v.Width && y >= v.y && y < v.y+v.Height {
 659                 screen.SetContent(x, y, ch, combc, style)
 660         }
 661 }
 662
 663 // DisplayView renders the view to the screen
 664 func (v *View) DisplayView() {
 665         if v.Type == vtLog {
 666                 // Log views should always follow the cursor...
 667                 v.Relocate()
 668         }
 669
 670         if v.Buf.Settings["syntax"].(bool) {
 671                 v.matches = Match(v)
 672         }
 673
 674         // The charNum we are currently displaying
 675         // starts at the start of the viewport
 676         charNum := Loc{0, v.Topline}
 677
 678         // Convert the length of buffer to a string, and get the length of the string
 679         // We are going to have to offset by that amount
 680         maxLineLength := len(strconv.Itoa(v.Buf.NumLines))
 681
 682         if v.Buf.Settings["ruler"] == true {
 683                 // + 1 for the little space after the line number
 684                 v.lineNumOffset = maxLineLength + 1
 685         } else {
 686                 v.lineNumOffset = 0
 687         }
 688
 689         // We need to add to the line offset if there are gutter messages
 690         var hasGutterMessages bool
 691         for _, v := range v.messages {
 692                 if len(v) > 0 {
 693                         hasGutterMessages = true
 694                 }
 695         }
 696         if hasGutterMessages {
 697                 v.lineNumOffset += 2
 698         }
 699
 700         if v.x != 0 {
 701                 // One space for the extra split divider
 702                 v.lineNumOffset++
 703         }
 704
 705         // These represent the current screen coordinates
 706         screenX, screenY := v.x, v.y-1
 707
 708         highlightStyle := defStyle
 709         curLineN := 0
 710
 711         // ViewLine is the current line from the top of the viewport
 712         for viewLine := 0; viewLine < v.Height; viewLine++ {
 713                 screenY++
 714                 screenX = v.x
 715
 716                 // This is the current line number of the buffer that we are drawing
 717                 curLineN = viewLine + v.Topline
 718
 719                 if screenY-v.y >= v.Height {
 720                         break
 721                 }
 722
 723                 if v.x != 0 {
 724                         dividerStyle := defStyle.Reverse(true)
 725                         if style, ok := colorscheme["divider"]; ok {
 726                                 dividerStyle = style
 727                         }
 728                         // Draw the split divider
 729                         v.drawCell(screenX, screenY, tcell.RuneVLine, nil, dividerStyle)
 730                         screenX++
 731                 }
 732
 733                 // If the buffer is smaller than the view height we have to clear all this space
 734                 if curLineN >= v.Buf.NumLines {
 735                         for i := screenX; i < v.x+v.Width; i++ {
 736                                 v.drawCell(i, screenY, ' ', nil, defStyle)
 737                         }
 738
 739                         continue
 740                 }
 741                 line := v.Buf.Line(curLineN)
 742
 743                 // If there are gutter messages we need to display the '>>' symbol here
 744                 if hasGutterMessages {
 745                         // msgOnLine stores whether or not there is a gutter message on this line in particular
 746                         msgOnLine := false
 747                         for k := range v.messages {
 748                                 for _, msg := range v.messages[k] {
 749                                         if msg.lineNum == curLineN {
 750                                                 msgOnLine = true
 751                                                 gutterStyle := defStyle
 752                                                 switch msg.kind {
 753                                                 case GutterInfo:
 754                                                         if style, ok := colorscheme["gutter-info"]; ok {
 755                                                                 gutterStyle = style
 756                                                         }
 757                                                 case GutterWarning:
 758                                                         if style, ok := colorscheme["gutter-warning"]; ok {
 759                                                                 gutterStyle = style
 760                                                         }
 761                                                 case GutterError:
 762                                                         if style, ok := colorscheme["gutter-error"]; ok {
 763                                                                 gutterStyle = style
 764                                                         }
 765                                                 }
 766                                                 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
 767                                                 screenX++
 768                                                 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
 769                                                 screenX++
 770                                                 if v.Cursor.Y == curLineN && !messenger.hasPrompt {
 771                                                         messenger.Message(msg.msg)
 772                                                         messenger.gutterMessage = true
 773                                                 }
 774                                         }
 775                                 }
 776                         }
 777                         // If there is no message on this line we just display an empty offset
 778                         if !msgOnLine {
 779                                 v.drawCell(screenX, screenY, ' ', nil, defStyle)
 780                                 screenX++
 781                                 v.drawCell(screenX, screenY, ' ', nil, defStyle)
 782                                 screenX++
 783                                 if v.Cursor.Y == curLineN && messenger.gutterMessage {
 784                                         messenger.Reset()
 785                                         messenger.gutterMessage = false
 786                                 }
 787                         }
 788                 }
 789
 790                 lineNumStyle := defStyle
 791                 if v.Buf.Settings["ruler"] == true {
 792                         // Write the line number
 793                         if style, ok := colorscheme["line-number"]; ok {
 794                                 lineNumStyle = style
 795                         }
 796                         if style, ok := colorscheme["current-line-number"]; ok {
 797                                 if curLineN == v.Cursor.Y && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() {
 798                                         lineNumStyle = style
 799                                 }
 800                         }
 801
 802                         lineNum := strconv.Itoa(curLineN + 1)
 803
 804                         // Write the spaces before the line number if necessary
 805                         for i := 0; i < maxLineLength-len(lineNum); i++ {
 806                                 v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
 807                                 screenX++
 808                         }
 809                         // Write the actual line number
 810                         for _, ch := range lineNum {
 811                                 v.drawCell(screenX, screenY, ch, nil, lineNumStyle)
 812                                 screenX++
 813                         }
 814
 815                         // Write the extra space
 816                         v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
 817                         screenX++
 818                 }
 819
 820                 // Now we actually draw the line
 821                 colN := 0
 822                 strWidth := 0
 823                 tabSize := int(v.Buf.Settings["tabsize"].(float64))
 824                 for _, ch := range line {
 825                         if v.Buf.Settings["softwrap"].(bool) {
 826                                 if screenX-v.x >= v.Width {
 827                                         screenY++
 828
 829                                         x := 0
 830                                         if hasGutterMessages {
 831                                                 v.drawCell(v.x+x, screenY, ' ', nil, defStyle)
 832                                                 x++
 833                                                 v.drawCell(v.x+x, screenY, ' ', nil, defStyle)
 834                                                 x++
 835                                         }
 836                                         for i := 0; i < v.lineNumOffset; i++ {
 837                                                 screen.SetContent(v.x+i+x, screenY, ' ', nil, lineNumStyle)
 838                                         }
 839                                         screenX = v.x + v.lineNumOffset
 840                                 }
 841                         }
 842
 843                         if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN && colN == v.Cursor.X {
 844                                 v.DisplayCursor(screenX-v.leftCol, screenY)
 845                         }
 846
 847                         lineStyle := defStyle
 848
 849                         if v.Buf.Settings["syntax"].(bool) {
 850                                 // Syntax highlighting is enabled
 851                                 highlightStyle = v.matches[viewLine][colN]
 852                         }
 853
 854                         if v.Cursor.HasSelection() &&
 855                                 (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
 856                                         charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
 857                                 // The current character is selected
 858                                 lineStyle = defStyle.Reverse(true)
 859
 860                                 if style, ok := colorscheme["selection"]; ok {
 861                                         lineStyle = style
 862                                 }
 863                         } else {
 864                                 lineStyle = highlightStyle
 865                         }
 866
 867                         // We need to display the background of the linestyle with the correct color if cursorline is enabled
 868                         // and this is the current view and there is no selection on this line and the cursor is on this line
 869                         if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
 870                                 if style, ok := colorscheme["cursor-line"]; ok {
 871                                         fg, _, _ := style.Decompose()
 872                                         lineStyle = lineStyle.Background(fg)
 873                                 }
 874                         }
 875
 876                         if ch == '\t' {
 877                                 // If the character we are displaying is a tab, we need to do a bunch of special things
 878
 879                                 // First the user may have configured an `indent-char` to be displayed to show that this
 880                                 // is a tab character
 881                                 lineIndentStyle := defStyle
 882                                 if style, ok := colorscheme["indent-char"]; ok && v.Buf.Settings["indentchar"].(string) != " " {
 883                                         lineIndentStyle = style
 884                                 }
 885                                 if v.Cursor.HasSelection() &&
 886                                         (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
 887                                                 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
 888
 889                                         lineIndentStyle = defStyle.Reverse(true)
 890
 891                                         if style, ok := colorscheme["selection"]; ok {
 892                                                 lineIndentStyle = style
 893                                         }
 894                                 }
 895                                 if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
 896                                         if style, ok := colorscheme["cursor-line"]; ok {
 897                                                 fg, _, _ := style.Decompose()
 898                                                 lineIndentStyle = lineIndentStyle.Background(fg)
 899                                         }
 900                                 }
 901                                 // Here we get the indent char
 902                                 indentChar := []rune(v.Buf.Settings["indentchar"].(string))
 903                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
 904                                         v.drawCell(screenX-v.leftCol, screenY, indentChar[0], nil, lineIndentStyle)
 905                                 }
 906                                 // Now the tab has to be displayed as a bunch of spaces
 907                                 visLoc := strWidth
 908                                 remainder := tabSize - (visLoc % tabSize)
 909                                 for i := 0; i < remainder-1; i++ {
 910                                         screenX++
 911                                         if screenX-v.x-v.leftCol >= v.lineNumOffset {
 912                                                 v.drawCell(screenX-v.leftCol, screenY, ' ', nil, lineStyle)
 913                                         }
 914                                 }
 915                                 strWidth += remainder
 916                         } else if runewidth.RuneWidth(ch) > 1 {
 917                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
 918                                         v.drawCell(screenX, screenY, ch, nil, lineStyle)
 919                                 }
 920                                 for i := 0; i < runewidth.RuneWidth(ch)-1; i++ {
 921                                         screenX++
 922                                         if screenX-v.x-v.leftCol >= v.lineNumOffset {
 923                                                 v.drawCell(screenX-v.leftCol, screenY, '<', nil, lineStyle)
 924                                         }
 925                                 }
 926                                 strWidth += StringWidth(string(ch), tabSize)
 927                         } else {
 928                                 if screenX-v.x-v.leftCol >= v.lineNumOffset {
 929                                         v.drawCell(screenX-v.leftCol, screenY, ch, nil, lineStyle)
 930                                 }
 931                                 strWidth += StringWidth(string(ch), tabSize)
 932                         }
 933                         charNum = charNum.Move(1, v.Buf)
 934                         screenX++
 935                         colN++
 936                 }
 937                 // Here we are at a newline
 938
 939                 if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN && colN == v.Cursor.X {
 940                         v.DisplayCursor(screenX-v.leftCol, screenY)
 941                 }
 942
 943                 // The newline may be selected, in which case we should draw the selection style
 944                 // with a space to represent it
 945                 if v.Cursor.HasSelection() &&
 946                         (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
 947                                 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
 948
 949                         selectStyle := defStyle.Reverse(true)
 950
 951                         if style, ok := colorscheme["selection"]; ok {
 952                                 selectStyle = style
 953                         }
 954                         v.drawCell(screenX, screenY, ' ', nil, selectStyle)
 955                         screenX++
 956                 }
 957
 958                 charNum = charNum.Move(1, v.Buf)
 959
 960                 for i := 0; i < v.Width; i++ {
 961                         lineStyle := defStyle
 962                         if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
 963                                 if style, ok := colorscheme["cursor-line"]; ok {
 964                                         fg, _, _ := style.Decompose()
 965                                         lineStyle = lineStyle.Background(fg)
 966                                 }
 967                         }
 968                         if screenX-v.x-v.leftCol+i >= v.lineNumOffset {
 969                                 colorcolumn := int(v.Buf.Settings["colorcolumn"].(float64))
 970                                 if colorcolumn != 0 && screenX-v.lineNumOffset+i == colorcolumn-1 {
 971                                         if style, ok := colorscheme["color-column"]; ok {
 972                                                 fg, _, _ := style.Decompose()
 973                                                 lineStyle = lineStyle.Background(fg)
 974                                         }
 975                                 }
 976                                 v.drawCell(screenX-v.leftCol+i, screenY, ' ', nil, lineStyle)
 977                         }
 978                 }
 979         }
 980 }
 981
 982 // DisplayCursor draws the current buffer's cursor to the screen
 983 func (v *View) DisplayCursor(x, y int) {
 984         // screen.ShowCursor(v.x+v.Cursor.GetVisualX()+v.lineNumOffset-v.leftCol, y)
 985         screen.ShowCursor(x, y)
 986 }
 987
 988 // Display renders the view, the cursor, and statusline
 989 func (v *View) Display() {
 990         v.DisplayView()
 991         // Don't draw the cursor if it is out of the viewport or if it has a selection
 992         if (v.Cursor.Y-v.Topline < 0 || v.Cursor.Y-v.Topline > v.Height-1) || v.Cursor.HasSelection() {
 993                 screen.HideCursor()
 994         }
 995         _, screenH := screen.Size()
 996         if v.Buf.Settings["statusline"].(bool) {
 997                 v.sline.Display()
 998         } else if (v.y + v.Height) != screenH-1 {
 999                 for x := 0; x < v.Width; x++ {
1000                         screen.SetContent(v.x+x, v.y+v.Height, '-', nil, defStyle.Reverse(true))
1001                 }
1002         }
1003 }