8 "github.com/mattn/go-runewidth"
9 "github.com/zyedidia/tcell"
12 // The View struct stores information about a view into a buffer.
13 // It stores information about the cursor, and the viewport
14 // that the user sees the buffer from.
16 // A pointer to the buffer's cursor for ease of access
19 // The topmost line, used for vertical scrolling
21 // The leftmost column, used for horizontal scrolling
24 // Percentage of the terminal window that this view takes up (from 0 to 100)
28 // Specifies whether or not this view holds a help buffer
31 // Actual with and height
35 // Where this view is located
38 // How much to offset because of line numbers
41 // Holds the list of gutter messages
42 messages map[string][]GutterMessage
44 // This is the index of this view in the views array
46 // What tab is this view stored in
54 // Since tcell doesn't differentiate between a mouse release event
55 // and a mouse move event with no keys pressed, we need to keep
56 // track of whether or not the mouse was pressed (or not released) last event to determine
57 // mouse release events
60 // This stores when the last click was
61 // This is useful for detecting double and triple clicks
62 lastClickTime time.Time
64 // lastCutTime stores when the last ctrl+k was issued.
65 // It is used for clearing the clipboard to replace it with fresh cut lines.
68 // freshClip returns true if the clipboard has never been pasted.
71 // Was the last mouse event actually a double click?
72 // Useful for detecting triple clicks -- if a double click is detected
73 // but the last mouse event was actually a double click, it's a triple click
75 // Same here, just to keep track for mouse move events
78 // Syntax highlighting matches
80 // The matches from the last frame
81 lastMatches SyntaxMatches
86 // NewView returns a new fullscreen view
87 func NewView(buf *Buffer) *View {
88 screenW, screenH := screen.Size()
89 return NewViewWidthHeight(buf, screenW, screenH-1)
92 // NewViewWidthHeight returns a new view with the specified width and height percentages
93 // Note that w and h are percentages not actual values
94 func NewViewWidthHeight(buf *Buffer, w, h int) *View {
106 v.messages = make(map[string][]GutterMessage)
108 v.sline = Statusline{
112 if settings["statusline"].(bool) {
119 func (v *View) ToggleStatusLine() {
120 if settings["statusline"].(bool) {
127 func (v *View) ToggleTabbar() {
130 // Include one line for the tab bar at the top
142 // ScrollUp scrolls the view up n lines (if possible)
143 func (v *View) ScrollUp(n int) {
144 // Try to scroll by n but if it would overflow, scroll by 1
145 if v.Topline-n >= 0 {
147 } else if v.Topline > 0 {
152 // ScrollDown scrolls the view down n lines (if possible)
153 func (v *View) ScrollDown(n int) {
154 // Try to scroll by n but if it would overflow, scroll by 1
155 if v.Topline+n <= v.Buf.NumLines-v.height {
157 } else if v.Topline < v.Buf.NumLines-v.height {
162 // CanClose returns whether or not the view can be closed
163 // If there are unsaved changes, the user will be asked if the view can be closed
164 // causing them to lose the unsaved changes
165 // The message is what to print after saying "You have unsaved changes. "
166 func (v *View) CanClose(msg string) bool {
167 if v.Buf.IsModified {
168 quit, canceled := messenger.Prompt("You have unsaved changes. "+msg, "Unsaved", NoCompletion)
170 if strings.ToLower(quit) == "yes" || strings.ToLower(quit) == "y" {
172 } else if strings.ToLower(quit) == "save" || strings.ToLower(quit) == "s" {
183 // OpenBuffer opens a new buffer in this view.
184 // This resets the topline, event handler and cursor.
185 func (v *View) OpenBuffer(buf *Buffer) {
189 v.Cursor = &buf.Cursor
192 v.Cursor.ResetSelection()
194 v.messages = make(map[string][]GutterMessage)
198 // Set mouseReleased to true because we assume the mouse is not being pressed when
199 // the editor is opened
200 v.mouseReleased = true
201 v.lastClickTime = time.Time{}
204 // CloseBuffer performs any closing functions on the buffer
205 func (v *View) CloseBuffer() {
211 // ReOpen reloads the current buffer
212 func (v *View) ReOpen() {
213 if v.CanClose("Continue? (yes, no, save) ") {
221 // HSplit opens a horizontal split with the given buffer
222 func (v *View) HSplit(buf *Buffer) bool {
223 v.splitNode.HSplit(buf)
224 tabs[v.TabNum].Resize()
228 // VSplit opens a vertical split with the given buffer
229 func (v *View) VSplit(buf *Buffer) bool {
230 v.splitNode.VSplit(buf)
231 tabs[v.TabNum].Resize()
235 // Relocate moves the view window so that the cursor is in view
236 // This is useful if the user has scrolled far away, and then starts typing
237 func (v *View) Relocate() bool {
240 scrollmargin := int(settings["scrollmargin"].(float64))
241 if cy < v.Topline+scrollmargin && cy > scrollmargin-1 {
242 v.Topline = cy - scrollmargin
244 } else if cy < v.Topline {
248 if cy > v.Topline+v.height-1-scrollmargin && cy < v.Buf.NumLines-scrollmargin {
249 v.Topline = cy - v.height + 1 + scrollmargin
251 } else if cy >= v.Buf.NumLines-scrollmargin && cy > v.height {
252 v.Topline = v.Buf.NumLines - v.height
256 cx := v.Cursor.GetVisualX()
261 if cx+v.lineNumOffset+1 > v.leftCol+v.width {
262 v.leftCol = cx - v.width + v.lineNumOffset + 1
268 // MoveToMouseClick moves the cursor to location x, y assuming x, y were given
270 func (v *View) MoveToMouseClick(x, y int) {
271 if y-v.Topline > v.height-1 {
273 y = v.height + v.Topline - 1
275 if y >= v.Buf.NumLines {
276 y = v.Buf.NumLines - 1
285 x = v.Cursor.GetCharPosInLine(y, x)
286 if x > Count(v.Buf.Line(y)) {
287 x = Count(v.Buf.Line(y))
291 v.Cursor.LastVisualX = v.Cursor.GetVisualX()
294 // HandleEvent handles an event passed by the main loop
295 func (v *View) HandleEvent(event tcell.Event) {
296 // This bool determines whether the view is relocated at the end of the function
297 // By default it's true because most events should cause a relocate
302 switch e := event.(type) {
303 case *tcell.EventResize:
305 tabs[v.TabNum].Resize()
306 case *tcell.EventKey:
307 if e.Key() == tcell.KeyRune && (e.Modifiers() == 0 || e.Modifiers() == tcell.ModShift) {
308 // Insert a character
309 if v.Cursor.HasSelection() {
310 v.Cursor.DeleteSelection()
311 v.Cursor.ResetSelection()
313 v.Buf.Insert(v.Cursor.Loc, string(e.Rune()))
316 for _, pl := range loadedPlugins {
317 _, err := Call(pl+".onRune", []string{string(e.Rune())})
318 if err != nil && !strings.HasPrefix(err.Error(), "function does not exist") {
323 for key, actions := range bindings {
324 if e.Key() == key.keyCode {
325 if e.Key() == tcell.KeyRune {
326 if e.Rune() != key.r {
330 if e.Modifiers() == key.modifiers {
332 for _, action := range actions {
333 relocate = action(v) || relocate
339 case *tcell.EventPaste:
340 if v.Cursor.HasSelection() {
341 v.Cursor.DeleteSelection()
342 v.Cursor.ResetSelection()
345 v.Buf.Insert(v.Cursor.Loc, clip)
346 v.Cursor.Loc = v.Cursor.Loc.Move(Count(clip), v.Buf)
348 case *tcell.EventMouse:
350 x -= v.lineNumOffset - v.leftCol + v.x
352 // Don't relocate for mouse events
355 button := e.Buttons()
361 v.MoveToMouseClick(x, y)
362 if time.Since(v.lastClickTime)/time.Millisecond < doubleClickThreshold {
365 v.lastClickTime = time.Now()
368 v.doubleClick = false
370 v.Cursor.SelectLine()
373 v.lastClickTime = time.Now()
376 v.tripleClick = false
378 v.Cursor.SelectWord()
381 v.doubleClick = false
382 v.tripleClick = false
383 v.lastClickTime = time.Now()
385 v.Cursor.OrigSelection[0] = v.Cursor.Loc
386 v.Cursor.CurSelection[0] = v.Cursor.Loc
387 v.Cursor.CurSelection[1] = v.Cursor.Loc
389 v.mouseReleased = false
390 } else if !v.mouseReleased {
391 v.MoveToMouseClick(x, y)
393 v.Cursor.AddLineToSelection()
394 } else if v.doubleClick {
395 v.Cursor.AddWordToSelection()
397 v.Cursor.CurSelection[1] = v.Cursor.Loc
400 case tcell.ButtonNone:
401 // Mouse event with no click
402 if !v.mouseReleased {
403 // Mouse was just released
405 // Relocating here isn't really necessary because the cursor will
406 // be in the right place from the last mouse event
407 // However, if we are running in a terminal that doesn't support mouse motion
408 // events, this still allows the user to make selections, except only after they
411 if !v.doubleClick && !v.tripleClick {
412 v.MoveToMouseClick(x, y)
413 v.Cursor.CurSelection[1] = v.Cursor.Loc
415 v.mouseReleased = true
419 scrollspeed := int(settings["scrollspeed"].(float64))
420 v.ScrollUp(scrollspeed)
421 case tcell.WheelDown:
423 scrollspeed := int(settings["scrollspeed"].(float64))
424 v.ScrollDown(scrollspeed)
431 if settings["syntax"].(bool) {
436 // GutterMessage creates a message in this view's gutter
437 func (v *View) GutterMessage(section string, lineN int, msg string, kind int) {
439 gutterMsg := GutterMessage{
444 for _, v := range v.messages {
445 for _, gmsg := range v {
446 if gmsg.lineNum == lineN {
451 messages := v.messages[section]
452 v.messages[section] = append(messages, gutterMsg)
455 // ClearGutterMessages clears all gutter messages from a given section
456 func (v *View) ClearGutterMessages(section string) {
457 v.messages[section] = []GutterMessage{}
460 // ClearAllGutterMessages clears all the gutter messages
461 func (v *View) ClearAllGutterMessages() {
462 for k := range v.messages {
463 v.messages[k] = []GutterMessage{}
467 func (v *View) drawCell(x, y int, ch rune, combc []rune, style tcell.Style) {
468 if x >= v.x && x < v.x+v.width && y >= v.y && y < v.y+v.height {
469 screen.SetContent(x, y, ch, combc, style)
473 // DisplayView renders the view to the screen
474 func (v *View) DisplayView() {
475 // The charNum we are currently displaying
476 // starts at the start of the viewport
477 charNum := Loc{0, v.Topline}
479 // Convert the length of buffer to a string, and get the length of the string
480 // We are going to have to offset by that amount
481 maxLineLength := len(strconv.Itoa(v.Buf.NumLines))
483 if settings["ruler"] == true {
484 // + 1 for the little space after the line number
485 v.lineNumOffset = maxLineLength + 1
490 // We need to add to the line offset if there are gutter messages
491 var hasGutterMessages bool
492 for _, v := range v.messages {
494 hasGutterMessages = true
497 if hasGutterMessages {
502 // One space for the extra split divider
506 // These represent the current screen coordinates
507 screenX, screenY := 0, 0
509 highlightStyle := defStyle
511 // ViewLine is the current line from the top of the viewport
512 for viewLine := 0; viewLine < v.height; viewLine++ {
513 screenY = v.y + viewLine
516 // This is the current line number of the buffer that we are drawing
517 curLineN := viewLine + v.Topline
520 // Draw the split divider
521 v.drawCell(screenX, screenY, '|', nil, defStyle.Reverse(true))
525 // If the buffer is smaller than the view height we have to clear all this space
526 if curLineN >= v.Buf.NumLines {
527 for i := screenX; i < v.x+v.width; i++ {
528 v.drawCell(i, screenY, ' ', nil, defStyle)
533 line := v.Buf.Line(curLineN)
535 // If there are gutter messages we need to display the '>>' symbol here
536 if hasGutterMessages {
537 // msgOnLine stores whether or not there is a gutter message on this line in particular
539 for k := range v.messages {
540 for _, msg := range v.messages[k] {
541 if msg.lineNum == curLineN {
543 gutterStyle := defStyle
546 if style, ok := colorscheme["gutter-info"]; ok {
550 if style, ok := colorscheme["gutter-warning"]; ok {
554 if style, ok := colorscheme["gutter-error"]; ok {
558 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
560 v.drawCell(screenX, screenY, '>', nil, gutterStyle)
562 if v.Cursor.Y == curLineN {
563 messenger.Message(msg.msg)
564 messenger.gutterMessage = true
569 // If there is no message on this line we just display an empty offset
571 v.drawCell(screenX, screenY, ' ', nil, defStyle)
573 v.drawCell(screenX, screenY, ' ', nil, defStyle)
575 if v.Cursor.Y == curLineN && messenger.gutterMessage {
577 messenger.gutterMessage = false
582 if settings["ruler"] == true {
583 // Write the line number
584 lineNumStyle := defStyle
585 if style, ok := colorscheme["line-number"]; ok {
588 if style, ok := colorscheme["current-line-number"]; ok {
589 if curLineN == v.Cursor.Y {
594 lineNum := strconv.Itoa(curLineN + 1)
596 // Write the spaces before the line number if necessary
597 for i := 0; i < maxLineLength-len(lineNum); i++ {
598 v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
601 // Write the actual line number
602 for _, ch := range lineNum {
603 v.drawCell(screenX, screenY, ch, nil, lineNumStyle)
607 // Write the extra space
608 v.drawCell(screenX, screenY, ' ', nil, lineNumStyle)
612 // Now we actually draw the line
613 for colN, ch := range line {
614 lineStyle := defStyle
616 if settings["syntax"].(bool) {
617 // Syntax highlighting is enabled
618 highlightStyle = v.matches[viewLine][colN]
621 if v.Cursor.HasSelection() &&
622 (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
623 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
624 // The current character is selected
625 lineStyle = defStyle.Reverse(true)
627 if style, ok := colorscheme["selection"]; ok {
631 lineStyle = highlightStyle
634 // We need to display the background of the linestyle with the correct color if cursorline is enabled
635 // and this is the current view and there is no selection on this line and the cursor is on this line
636 if settings["cursorline"].(bool) && tabs[curTab].curView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
637 if style, ok := colorscheme["cursor-line"]; ok {
638 fg, _, _ := style.Decompose()
639 lineStyle = lineStyle.Background(fg)
644 // If the character we are displaying is a tab, we need to do a bunch of special things
646 // First the user may have configured an `indent-char` to be displayed to show that this
647 // is a tab character
648 lineIndentStyle := defStyle
649 if style, ok := colorscheme["indent-char"]; ok {
650 lineIndentStyle = style
652 if v.Cursor.HasSelection() &&
653 (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
654 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
656 lineIndentStyle = defStyle.Reverse(true)
658 if style, ok := colorscheme["selection"]; ok {
659 lineIndentStyle = style
662 if settings["cursorline"].(bool) && tabs[curTab].curView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
663 if style, ok := colorscheme["cursor-line"]; ok {
664 fg, _, _ := style.Decompose()
665 lineIndentStyle = lineIndentStyle.Background(fg)
668 // Here we get the indent char
669 indentChar := []rune(settings["indentchar"].(string))
670 if screenX-v.x-v.leftCol >= v.lineNumOffset {
671 v.drawCell(screenX-v.leftCol, screenY, indentChar[0], nil, lineIndentStyle)
673 // Now the tab has to be displayed as a bunch of spaces
674 tabSize := int(settings["tabsize"].(float64))
675 for i := 0; i < tabSize-1; i++ {
677 if screenX-v.x-v.leftCol >= v.lineNumOffset {
678 v.drawCell(screenX-v.leftCol, screenY, ' ', nil, lineStyle)
681 } else if runewidth.RuneWidth(ch) > 1 {
682 if screenX-v.x-v.leftCol >= v.lineNumOffset {
683 v.drawCell(screenX, screenY, ch, nil, lineStyle)
685 for i := 0; i < runewidth.RuneWidth(ch)-1; i++ {
687 if screenX-v.x-v.leftCol >= v.lineNumOffset {
688 v.drawCell(screenX-v.leftCol, screenY, '<', nil, lineStyle)
692 if screenX-v.x-v.leftCol >= v.lineNumOffset {
693 v.drawCell(screenX-v.leftCol, screenY, ch, nil, lineStyle)
696 charNum = charNum.Move(1, v.Buf)
699 // Here we are at a newline
701 // The newline may be selected, in which case we should draw the selection style
702 // with a space to represent it
703 if v.Cursor.HasSelection() &&
704 (charNum.GreaterEqual(v.Cursor.CurSelection[0]) && charNum.LessThan(v.Cursor.CurSelection[1]) ||
705 charNum.LessThan(v.Cursor.CurSelection[0]) && charNum.GreaterEqual(v.Cursor.CurSelection[1])) {
707 selectStyle := defStyle.Reverse(true)
709 if style, ok := colorscheme["selection"]; ok {
712 v.drawCell(screenX, screenY, ' ', nil, selectStyle)
716 charNum = charNum.Move(1, v.Buf)
718 for i := 0; i < v.width; i++ {
719 lineStyle := defStyle
720 if settings["cursorline"].(bool) && tabs[curTab].curView == v.Num && !v.Cursor.HasSelection() && v.Cursor.Y == curLineN {
721 if style, ok := colorscheme["cursor-line"]; ok {
722 fg, _, _ := style.Decompose()
723 lineStyle = lineStyle.Background(fg)
726 if screenX-v.x-v.leftCol+i >= v.lineNumOffset {
727 v.drawCell(screenX-v.leftCol+i, screenY, ' ', nil, lineStyle)
733 // DisplayCursor draws the current buffer's cursor to the screen
734 func (v *View) DisplayCursor() {
735 // Don't draw the cursor if it is out of the viewport or if it has a selection
736 if (v.Cursor.Y-v.Topline < 0 || v.Cursor.Y-v.Topline > v.height-1) || v.Cursor.HasSelection() {
739 screen.ShowCursor(v.x+v.Cursor.GetVisualX()+v.lineNumOffset-v.leftCol, v.Cursor.Y-v.Topline+v.y)
743 // Display renders the view, the cursor, and statusline
744 func (v *View) Display() {
746 if v.Num == tabs[curTab].curView {
749 _, screenH := screen.Size()
750 if settings["statusline"].(bool) {
752 } else if (v.y + v.height) != screenH-1 {
753 for x := 0; x < v.width; x++ {
754 screen.SetContent(v.x+x, v.y+v.height, '-', nil, defStyle.Reverse(true))