erm/app/darktile/termutil/buffer.go

892 lines
21 KiB
Go

package termutil
import (
"image"
"image/color"
"sync"
)
const TabSize = 8
type CursorShape uint8
const (
CursorShapeBlinkingBlock CursorShape = iota
CursorShapeDefault
CursorShapeSteadyBlock
CursorShapeBlinkingUnderline
CursorShapeSteadyUnderline
CursorShapeBlinkingBar
CursorShapeSteadyBar
)
type Buffer struct {
lines []Line
savedCursorPos Position
savedCursorAttr *CellAttributes
cursorShape CursorShape
savedCharsets []*map[rune]rune
savedCurrentCharset int
topMargin uint // see DECSTBM docs - this is for scrollable regions
bottomMargin uint // see DECSTBM docs - this is for scrollable regions
viewWidth uint16
viewHeight uint16
cursorPosition Position // raw
cursorAttr CellAttributes
scrollLinesFromBottom uint
maxLines uint64
tabStops []uint16
charsets []*map[rune]rune // array of 2 charsets, nil means ASCII (no conversion)
currentCharset int // active charset index in charsets array, valid values are 0 or 1
modes Modes
selectionStart *Position
selectionEnd *Position
highlightStart *Position
highlightEnd *Position
highlightAnnotation *Annotation
sixels []Sixel
selectionMu sync.Mutex
}
type Annotation struct {
Image image.Image
Text string
Width float64 // Width in cells
Height float64 // Height in cells
}
type Selection struct {
Start Position
End Position
}
type Position struct {
Line uint64
Col uint16
}
// NewBuffer creates a new terminal buffer
func NewBuffer(width, height uint16, maxLines uint64, fg color.Color, bg color.Color) *Buffer {
b := &Buffer{
lines: []Line{},
viewHeight: height,
viewWidth: width,
maxLines: maxLines,
topMargin: 0,
bottomMargin: uint(height - 1),
cursorAttr: CellAttributes{
fgColour: fg,
bgColour: bg,
},
charsets: []*map[rune]rune{nil, nil},
modes: Modes{
LineFeedMode: true,
AutoWrap: true,
ShowCursor: true,
SixelScrolling: true,
},
cursorShape: CursorShapeDefault,
}
return b
}
func (buffer *Buffer) SetCursorShape(shape CursorShape) {
buffer.cursorShape = shape
}
func (buffer *Buffer) GetCursorShape() CursorShape {
return buffer.cursorShape
}
func (buffer *Buffer) IsCursorVisible() bool {
return buffer.modes.ShowCursor
}
func (buffer *Buffer) IsApplicationCursorKeysModeEnabled() bool {
return buffer.modes.ApplicationCursorKeys
}
func (buffer *Buffer) HasScrollableRegion() bool {
return buffer.topMargin > 0 || buffer.bottomMargin < uint(buffer.ViewHeight())-1
}
func (buffer *Buffer) InScrollableRegion() bool {
cursorVY := buffer.convertRawLineToViewLine(buffer.cursorPosition.Line)
return buffer.HasScrollableRegion() && uint(cursorVY) >= buffer.topMargin && uint(cursorVY) <= buffer.bottomMargin
}
// NOTE: bottom is exclusive
func (buffer *Buffer) getAreaScrollRange() (top uint64, bottom uint64) {
top = buffer.convertViewLineToRawLine(uint16(buffer.topMargin))
bottom = buffer.convertViewLineToRawLine(uint16(buffer.bottomMargin)) + 1
if bottom > uint64(len(buffer.lines)) {
bottom = uint64(len(buffer.lines))
}
return top, bottom
}
func (buffer *Buffer) areaScrollDown(lines uint16) {
// NOTE: bottom is exclusive
top, bottom := buffer.getAreaScrollRange()
for i := bottom; i > top; {
i--
if i >= top+uint64(lines) {
buffer.lines[i] = buffer.lines[i-uint64(lines)]
} else {
buffer.lines[i] = newLine()
}
}
}
func (buffer *Buffer) areaScrollUp(lines uint16) {
// NOTE: bottom is exclusive
top, bottom := buffer.getAreaScrollRange()
for i := top; i < bottom; i++ {
from := i + uint64(lines)
if from < bottom {
buffer.lines[i] = buffer.lines[from]
} else {
buffer.lines[i] = newLine()
}
}
}
func (buffer *Buffer) saveCursor() {
copiedAttr := buffer.cursorAttr
buffer.savedCursorAttr = &copiedAttr
buffer.savedCursorPos = buffer.cursorPosition
buffer.savedCharsets = make([]*map[rune]rune, len(buffer.charsets))
copy(buffer.savedCharsets, buffer.charsets)
buffer.savedCurrentCharset = buffer.currentCharset
}
func (buffer *Buffer) restoreCursor() {
// TODO: Do we need to restore attributes on cursor restore? conflicting sources but vim + htop work better without doing so
//if buffer.savedCursorAttr != nil {
// copiedAttr := *buffer.savedCursorAttr
// copiedAttr.bgColour = buffer.defaultCell(false).attr.bgColour
// copiedAttr.fgColour = buffer.defaultCell(false).attr.fgColour
// buffer.cursorAttr = copiedAttr
//}
buffer.cursorPosition = buffer.savedCursorPos
if buffer.savedCharsets != nil {
buffer.charsets = make([]*map[rune]rune, len(buffer.savedCharsets))
copy(buffer.charsets, buffer.savedCharsets)
buffer.currentCharset = buffer.savedCurrentCharset
}
}
func (buffer *Buffer) getCursorAttr() *CellAttributes {
return &buffer.cursorAttr
}
func (buffer *Buffer) GetCell(viewCol uint16, viewRow uint16) *Cell {
rawLine := buffer.convertViewLineToRawLine(viewRow)
return buffer.getRawCell(viewCol, rawLine)
}
func (buffer *Buffer) getRawCell(viewCol uint16, rawLine uint64) *Cell {
if rawLine >= uint64(len(buffer.lines)) {
return nil
}
line := &buffer.lines[rawLine]
if int(viewCol) >= len(line.cells) {
return nil
}
return &line.cells[viewCol]
}
// Column returns cursor column
func (buffer *Buffer) CursorColumn() uint16 {
// @todo originMode and left margin
return buffer.cursorPosition.Col
}
// CursorLineAbsolute returns absolute cursor line coordinate (ignoring Origin Mode) - view format
func (buffer *Buffer) CursorLineAbsolute() uint16 {
cursorVY := buffer.convertRawLineToViewLine(buffer.cursorPosition.Line)
return cursorVY
}
// CursorLine returns cursor line (in Origin Mode it is relative to the top margin)
func (buffer *Buffer) CursorLine() uint16 {
if buffer.modes.OriginMode {
return buffer.CursorLineAbsolute() - uint16(buffer.topMargin)
}
return buffer.CursorLineAbsolute()
}
func (buffer *Buffer) TopMargin() uint {
return buffer.topMargin
}
func (buffer *Buffer) BottomMargin() uint {
return buffer.bottomMargin
}
// cursor Y (raw)
func (buffer *Buffer) RawLine() uint64 {
return buffer.cursorPosition.Line
}
func (buffer *Buffer) convertViewLineToRawLine(viewLine uint16) uint64 {
rawHeight := buffer.Height()
if int(buffer.viewHeight) > rawHeight {
return uint64(viewLine)
}
return uint64(int(viewLine) + (rawHeight - int(buffer.viewHeight+uint16(buffer.scrollLinesFromBottom))))
}
func (buffer *Buffer) convertRawLineToViewLine(rawLine uint64) uint16 {
rawHeight := buffer.Height()
if int(buffer.viewHeight) > rawHeight {
return uint16(rawLine)
}
return uint16(int(rawLine) - (rawHeight - int(buffer.viewHeight+uint16(buffer.scrollLinesFromBottom))))
}
func (buffer *Buffer) GetVPosition() int {
result := int(uint(buffer.Height()) - uint(buffer.ViewHeight()) - buffer.scrollLinesFromBottom)
if result < 0 {
result = 0
}
return result
}
// Width returns the width of the buffer in columns
func (buffer *Buffer) Width() uint16 {
return buffer.viewWidth
}
func (buffer *Buffer) ViewWidth() uint16 {
return buffer.viewWidth
}
func (buffer *Buffer) Height() int {
return len(buffer.lines)
}
func (buffer *Buffer) ViewHeight() uint16 {
return buffer.viewHeight
}
func (buffer *Buffer) deleteLine() {
index := int(buffer.RawLine())
buffer.lines = buffer.lines[:index+copy(buffer.lines[index:], buffer.lines[index+1:])]
}
func (buffer *Buffer) insertLine() {
if !buffer.InScrollableRegion() {
pos := buffer.RawLine()
maxLines := buffer.GetMaxLines()
newLineCount := uint64(len(buffer.lines) + 1)
if newLineCount > maxLines {
newLineCount = maxLines
}
out := make([]Line, newLineCount)
copy(
out[:pos-(uint64(len(buffer.lines))+1-newLineCount)],
buffer.lines[uint64(len(buffer.lines))+1-newLineCount:pos])
out[pos] = newLine()
copy(out[pos+1:], buffer.lines[pos:])
buffer.lines = out
} else {
topIndex := buffer.convertViewLineToRawLine(uint16(buffer.topMargin))
bottomIndex := buffer.convertViewLineToRawLine(uint16(buffer.bottomMargin))
before := buffer.lines[:topIndex]
after := buffer.lines[bottomIndex+1:]
out := make([]Line, len(buffer.lines))
copy(out[0:], before)
pos := buffer.RawLine()
for i := topIndex; i < bottomIndex; i++ {
if i < pos {
out[i] = buffer.lines[i]
} else {
out[i+1] = buffer.lines[i]
}
}
copy(out[bottomIndex+1:], after)
out[pos] = newLine()
buffer.lines = out
}
}
func (buffer *Buffer) insertBlankCharacters(count int) {
index := int(buffer.RawLine())
for i := 0; i < count; i++ {
cells := buffer.lines[index].cells
buffer.lines[index].cells = append(cells[:buffer.cursorPosition.Col], append([]Cell{buffer.defaultCell(true)}, cells[buffer.cursorPosition.Col:]...)...)
}
}
func (buffer *Buffer) insertLines(count int) {
if buffer.HasScrollableRegion() && !buffer.InScrollableRegion() {
// should have no effect outside of scrollable region
return
}
buffer.cursorPosition.Col = 0
for i := 0; i < count; i++ {
buffer.insertLine()
}
}
func (buffer *Buffer) deleteLines(count int) {
if buffer.HasScrollableRegion() && !buffer.InScrollableRegion() {
// should have no effect outside of scrollable region
return
}
buffer.cursorPosition.Col = 0
for i := 0; i < count; i++ {
buffer.deleteLine()
}
}
func (buffer *Buffer) index() {
// This sequence causes the active position to move downward one line without changing the column position.
// If the active position is at the bottom margin, a scroll up is performed."
cursorVY := buffer.convertRawLineToViewLine(buffer.cursorPosition.Line)
if buffer.InScrollableRegion() {
if uint(cursorVY) < buffer.bottomMargin {
buffer.cursorPosition.Line++
} else {
buffer.areaScrollUp(1)
}
return
}
if cursorVY >= buffer.ViewHeight()-1 {
buffer.lines = append(buffer.lines, newLine())
maxLines := buffer.GetMaxLines()
if uint64(len(buffer.lines)) > maxLines {
copy(buffer.lines, buffer.lines[uint64(len(buffer.lines))-maxLines:])
buffer.lines = buffer.lines[:maxLines]
}
}
buffer.cursorPosition.Line++
}
func (buffer *Buffer) reverseIndex() {
cursorVY := buffer.convertRawLineToViewLine(buffer.cursorPosition.Line)
if uint(cursorVY) == buffer.topMargin {
buffer.areaScrollDown(1)
} else if cursorVY > 0 {
buffer.cursorPosition.Line--
}
}
// write will write a rune to the terminal at the position of the cursor, and increment the cursor position
func (buffer *Buffer) write(runes ...MeasuredRune) {
// scroll to bottom on input
buffer.scrollLinesFromBottom = 0
for _, r := range runes {
line := buffer.getCurrentLine()
if buffer.modes.ReplaceMode {
if buffer.CursorColumn() >= buffer.Width() {
if buffer.modes.AutoWrap {
buffer.cursorPosition.Line++
buffer.cursorPosition.Col = 0
line = buffer.getCurrentLine()
} else {
// no more room on line and wrapping is disabled
return
}
}
for int(buffer.CursorColumn()) >= len(line.cells) {
line.append(buffer.defaultCell(int(buffer.CursorColumn()) == len(line.cells)))
}
line.cells[buffer.cursorPosition.Col].attr = buffer.cursorAttr
line.cells[buffer.cursorPosition.Col].setRune(r)
buffer.incrementCursorPosition()
continue
}
if buffer.CursorColumn() >= buffer.Width() { // if we're after the line, move to next
if buffer.modes.AutoWrap {
buffer.newLineEx(true)
newLine := buffer.getCurrentLine()
if len(newLine.cells) == 0 {
newLine.append(buffer.defaultCell(true))
}
cell := &newLine.cells[0]
cell.setRune(r)
cell.attr = buffer.cursorAttr
} else {
// no more room on line and wrapping is disabled
return
}
} else {
for int(buffer.CursorColumn()) >= len(line.cells) {
line.append(buffer.defaultCell(int(buffer.CursorColumn()) == len(line.cells)))
}
cell := &line.cells[buffer.CursorColumn()]
cell.setRune(r)
cell.attr = buffer.cursorAttr
}
buffer.incrementCursorPosition()
}
}
func (buffer *Buffer) incrementCursorPosition() {
// we can increment one column past the end of the line.
// this is effectively the beginning of the next line, except when we \r etc.
if buffer.CursorColumn() < buffer.Width() {
buffer.cursorPosition.Col++
}
}
func (buffer *Buffer) inDoWrap() bool {
// xterm uses 'do_wrap' flag for this special terminal state
// we use the cursor position right after the boundary
// let's see how it works out
return buffer.cursorPosition.Col == buffer.viewWidth // @todo rightMargin
}
func (buffer *Buffer) backspace() {
if buffer.cursorPosition.Col == 0 {
line := buffer.getCurrentLine()
if line.wrapped {
buffer.movePosition(int16(buffer.Width()-1), -1)
}
} else if buffer.inDoWrap() {
// the "do_wrap" implementation
buffer.movePosition(-2, 0)
} else {
buffer.movePosition(-1, 0)
}
}
func (buffer *Buffer) carriageReturn() {
cursorVY := buffer.convertRawLineToViewLine(buffer.cursorPosition.Line)
for {
line := buffer.getCurrentLine()
if line == nil {
break
}
if line.wrapped && cursorVY > 0 {
buffer.cursorPosition.Line--
} else {
break
}
}
buffer.cursorPosition.Col = 0
}
func (buffer *Buffer) tab() {
tabStop := buffer.getNextTabStopAfter(buffer.cursorPosition.Col)
for buffer.cursorPosition.Col < tabStop && buffer.cursorPosition.Col < buffer.viewWidth-1 { // @todo rightMargin
buffer.write(MeasuredRune{Rune: ' ', Width: 1})
}
}
// return next tab stop x pos
func (buffer *Buffer) getNextTabStopAfter(col uint16) uint16 {
defaultStop := col + (TabSize - (col % TabSize))
if defaultStop == col {
defaultStop += TabSize
}
var low uint16
for _, stop := range buffer.tabStops {
if stop > col {
if stop < low || low == 0 {
low = stop
}
}
}
if low == 0 {
return defaultStop
}
return low
}
func (buffer *Buffer) newLine() {
buffer.newLineEx(false)
}
func (buffer *Buffer) verticalTab() {
buffer.index()
for {
line := buffer.getCurrentLine()
if !line.wrapped {
break
}
buffer.index()
}
}
func (buffer *Buffer) newLineEx(forceCursorToMargin bool) {
if buffer.IsNewLineMode() || forceCursorToMargin {
buffer.cursorPosition.Col = 0
}
buffer.index()
for {
line := buffer.getCurrentLine()
if !line.wrapped {
break
}
buffer.index()
}
}
func (buffer *Buffer) movePosition(x int16, y int16) {
var toX uint16
var toY uint16
if int16(buffer.CursorColumn())+x < 0 {
toX = 0
} else {
toX = uint16(int16(buffer.CursorColumn()) + x)
}
// should either use CursorLine() and setPosition() or use absolutes, mind Origin Mode (DECOM)
if int16(buffer.CursorLine())+y < 0 {
toY = 0
} else {
toY = uint16(int16(buffer.CursorLine()) + y)
}
buffer.setPosition(toX, toY)
}
func (buffer *Buffer) setPosition(col uint16, line uint16) {
useCol := col
useLine := line
maxLine := buffer.ViewHeight() - 1
if buffer.modes.OriginMode {
useLine += uint16(buffer.topMargin)
maxLine = uint16(buffer.bottomMargin)
// @todo left and right margins
}
if useLine > maxLine {
useLine = maxLine
}
if useCol >= buffer.ViewWidth() {
useCol = buffer.ViewWidth() - 1
}
buffer.cursorPosition.Col = useCol
buffer.cursorPosition.Line = buffer.convertViewLineToRawLine(useLine)
}
func (buffer *Buffer) GetVisibleLines() []Line {
lines := []Line{}
for i := buffer.Height() - int(buffer.ViewHeight()); i < buffer.Height(); i++ {
y := i - int(buffer.scrollLinesFromBottom)
if y >= 0 && y < len(buffer.lines) {
lines = append(lines, buffer.lines[y])
}
}
return lines
}
// tested to here
func (buffer *Buffer) clear() {
for i := 0; i < int(buffer.ViewHeight()); i++ {
buffer.lines = append(buffer.lines, newLine())
}
buffer.setPosition(0, 0)
}
// creates if necessary
func (buffer *Buffer) getCurrentLine() *Line {
cursorVY := buffer.convertRawLineToViewLine(buffer.cursorPosition.Line)
return buffer.getViewLine(cursorVY)
}
func (buffer *Buffer) getViewLine(index uint16) *Line {
if index >= buffer.ViewHeight() {
return &buffer.lines[len(buffer.lines)-1]
}
if len(buffer.lines) < int(buffer.ViewHeight()) {
for int(index) >= len(buffer.lines) {
buffer.lines = append(buffer.lines, newLine())
}
return &buffer.lines[int(index)]
}
if raw := int(buffer.convertViewLineToRawLine(index)); raw < len(buffer.lines) {
return &buffer.lines[raw]
}
return nil
}
func (buffer *Buffer) eraseLine() {
buffer.clearSixelsAtRawLine(buffer.cursorPosition.Line)
line := buffer.getCurrentLine()
for i := 0; i < int(buffer.viewWidth); i++ {
if i >= len(line.cells) {
line.cells = append(line.cells, buffer.defaultCell(false))
} else {
line.cells[i] = buffer.defaultCell(false)
}
}
}
func (buffer *Buffer) eraseLineToCursor() {
buffer.clearSixelsAtRawLine(buffer.cursorPosition.Line)
line := buffer.getCurrentLine()
for i := 0; i <= int(buffer.cursorPosition.Col); i++ {
if i < len(line.cells) {
line.cells[i].erase(buffer.cursorAttr.bgColour)
}
}
}
func (buffer *Buffer) eraseLineFromCursor() {
buffer.clearSixelsAtRawLine(buffer.cursorPosition.Line)
line := buffer.getCurrentLine()
for i := buffer.cursorPosition.Col; i < buffer.viewWidth; i++ {
if int(i) >= len(line.cells) {
line.cells = append(line.cells, buffer.defaultCell(false))
} else {
line.cells[i] = buffer.defaultCell(false)
}
}
}
func (buffer *Buffer) eraseDisplay() {
for i := uint16(0); i < (buffer.ViewHeight()); i++ {
rawLine := buffer.convertViewLineToRawLine(i)
buffer.clearSixelsAtRawLine(rawLine)
if int(rawLine) < len(buffer.lines) {
buffer.lines[int(rawLine)].cells = []Cell{}
}
}
}
func (buffer *Buffer) deleteChars(n int) {
line := buffer.getCurrentLine()
if int(buffer.cursorPosition.Col) >= len(line.cells) {
return
}
before := line.cells[:buffer.cursorPosition.Col]
if int(buffer.cursorPosition.Col)+n >= len(line.cells) {
n = len(line.cells) - int(buffer.cursorPosition.Col)
}
after := line.cells[int(buffer.cursorPosition.Col)+n:]
line.cells = append(before, after...)
}
func (buffer *Buffer) eraseCharacters(n int) {
line := buffer.getCurrentLine()
max := int(buffer.cursorPosition.Col) + n
if max > len(line.cells) {
max = len(line.cells)
}
for i := int(buffer.cursorPosition.Col); i < max; i++ {
line.cells[i].erase(buffer.cursorAttr.bgColour)
}
}
func (buffer *Buffer) eraseDisplayFromCursor() {
line := buffer.getCurrentLine()
max := int(buffer.cursorPosition.Col)
if max > len(line.cells) {
max = len(line.cells)
}
line.cells = line.cells[:max]
for rawLine := buffer.cursorPosition.Line + 1; int(rawLine) < len(buffer.lines); rawLine++ {
buffer.clearSixelsAtRawLine(rawLine)
buffer.lines[int(rawLine)].cells = []Cell{}
}
}
func (buffer *Buffer) eraseDisplayToCursor() {
line := buffer.getCurrentLine()
for i := 0; i <= int(buffer.cursorPosition.Col); i++ {
if i >= len(line.cells) {
break
}
line.cells[i].erase(buffer.cursorAttr.bgColour)
}
cursorVY := buffer.convertRawLineToViewLine(buffer.cursorPosition.Line)
for i := uint16(0); i < cursorVY; i++ {
rawLine := buffer.convertViewLineToRawLine(i)
buffer.clearSixelsAtRawLine(rawLine)
if int(rawLine) < len(buffer.lines) {
buffer.lines[int(rawLine)].cells = []Cell{}
}
}
}
func (buffer *Buffer) GetMaxLines() uint64 {
result := buffer.maxLines
if result < uint64(buffer.viewHeight) {
result = uint64(buffer.viewHeight)
}
return result
}
func (buffer *Buffer) setVerticalMargins(top uint, bottom uint) {
buffer.topMargin = top
buffer.bottomMargin = bottom
}
// resetVerticalMargins resets margins to extreme positions
func (buffer *Buffer) resetVerticalMargins(height uint) {
buffer.setVerticalMargins(0, height-1)
}
func (buffer *Buffer) defaultCell(applyEffects bool) Cell {
attr := buffer.cursorAttr
if !applyEffects {
attr.blink = false
attr.bold = false
attr.dim = false
attr.inverse = false
attr.underline = false
attr.dim = false
}
return Cell{attr: attr}
}
func (buffer *Buffer) IsNewLineMode() bool {
return !buffer.modes.LineFeedMode
}
func (buffer *Buffer) tabReset() {
buffer.tabStops = nil
}
func (buffer *Buffer) tabSet(index uint16) {
buffer.tabStops = append(buffer.tabStops, index)
}
func (buffer *Buffer) tabClear(index uint16) {
var filtered []uint16
for _, stop := range buffer.tabStops {
if stop != buffer.cursorPosition.Col {
filtered = append(filtered, stop)
}
}
buffer.tabStops = filtered
}
func (buffer *Buffer) IsTabSetAtCursor() bool {
if buffer.cursorPosition.Col%TabSize > 0 {
return false
}
for _, stop := range buffer.tabStops {
if stop == buffer.cursorPosition.Col {
return true
}
}
return false
}
func (buffer *Buffer) tabClearAtCursor() {
buffer.tabClear(buffer.cursorPosition.Col)
}
func (buffer *Buffer) tabSetAtCursor() {
buffer.tabSet(buffer.cursorPosition.Col)
}
func (buffer *Buffer) GetScrollOffset() uint {
return buffer.scrollLinesFromBottom
}
func (buffer *Buffer) SetScrollOffset(offset uint) {
buffer.scrollLinesFromBottom = offset
}
func (buffer *Buffer) ScrollToEnd() {
buffer.scrollLinesFromBottom = 0
}
func (buffer *Buffer) ScrollUp(lines uint) {
if int(buffer.scrollLinesFromBottom)+int(lines) < len(buffer.lines)-int(buffer.viewHeight) {
buffer.scrollLinesFromBottom += lines
} else {
lines := len(buffer.lines) - int(buffer.viewHeight)
if lines < 0 {
lines = 0
}
buffer.scrollLinesFromBottom = uint(lines)
}
}
func (buffer *Buffer) ScrollDown(lines uint) {
if int(buffer.scrollLinesFromBottom)-int(lines) >= 0 {
buffer.scrollLinesFromBottom -= lines
} else {
buffer.scrollLinesFromBottom = 0
}
}