func visibleLine() []rune {
width := display.LineWidth()
if len(currentLine) <= width {
return currentLine
}
if len(currentLine) <= width+currentScroll {
return currentLine[currentScroll:]
}
return currentLine[currentScroll : width+currentScroll]
}
func CursorAtEnd() {
width := display.LineWidth()
cursor = len(currentLine)
if len(currentLine) < width {
currentScroll = 0
} else {
currentScroll = len(currentLine) - width
}
display.ShowLine(visibleLine())
updateCursor()
}
func CursorRight() {
width := display.LineWidth()
if cursor < len(currentLine) {
cursor++
}
if cursor > width+currentScroll {
// LogS(fmt.Sprintf("-- %d", cursor))
currentScroll++
display.ShowLine(visibleLine())
}
updateCursor()
}
func AddRune(r rune) {
// Log([]rune(fmt.Sprintf("%d, %d", len(currentLine), cursor)))
if len(currentLine) <= cursor {
currentLine = append(currentLine, r)
cursor++
checkScrollRight()
return
}
copyLine := make([]rune, len(currentLine))
copy(copyLine, currentLine)
currentLine = append(append(copyLine[:cursor], r),
currentLine[cursor:]...)
if cursor-currentScroll >= display.LineWidth() {
checkScrollRight()
}
cursor++
}
func Backspace() {
if cursor == 0 {
return
}
width := display.LineWidth()
if cursor-currentScroll <= 0 && currentScroll != 0 {
currentScroll -= width
updateCursor()
}
if len(currentLine) <= cursor {
currentLine = currentLine[:cursor-1]
cursor--
} else {
currentLine = append(currentLine[:cursor-1], currentLine[cursor:]...)
cursor--
}
if cursor == width {
currentScroll = 0
updateCursor()
}
}
func checkScrollRight() {
width := display.LineWidth()
if len(currentLine)-currentScroll > width {
currentScroll++
}
}