package main
-import (
- "strings"
-)
-
-// FromCharPos converts from a character position to an x, y position
-func FromCharPos(loc int, buf *Buffer) (int, int) {
- return FromCharPosStart(0, 0, 0, loc, buf)
-}
-
-// FromCharPosStart converts from a character position to an x, y position, starting at the specified character location
-func FromCharPosStart(startLoc, startX, startY, loc int, buf *Buffer) (int, int) {
- charNum := startLoc
- x, y := startX, startY
-
- lineLen := Count(buf.Lines[y]) + 1
- for charNum+lineLen <= loc {
- charNum += lineLen
- y++
- if y >= buf.NumLines {
- return 0, 0
- }
- lineLen = Count(buf.Lines[y]) + 1
- }
- x = loc - charNum
-
- return x, y
-}
-
-// ToCharPos converts from an x, y position to a character position
-func ToCharPos(x, y int, buf *Buffer) int {
- loc := 0
- for i := 0; i < y; i++ {
- // + 1 for the newline
- loc += Count(buf.Lines[i]) + 1
- }
- loc += x
- return loc
-}
-
// The Cursor struct stores the location of the cursor in the view
// The complicated part about the cursor is storing its location.
// The cursor must be displayed at an x, y location, but since the buffer
// selection.
type Cursor struct {
buf *Buffer
-
- // The cursor display location
- X int
- Y int
+ Loc
// Last cursor x position
LastVisualX int
// The current selection as a range of character numbers (inclusive)
- CurSelection [2]int
+ CurSelection [2]Loc
// The original selection as a range of character numbers
// This is used for line and word selection where it is necessary
// to know what the original selection was
- OrigSelection [2]int
+ OrigSelection [2]Loc
}
-// Clamp makes sure that the cursor is in the bounds of the buffer
-// It cannot be less than 0 or greater than the buffer length
-func (c *Cursor) Clamp() {
- loc := c.Loc()
- if loc < 0 {
- c.SetLoc(0)
- } else if loc > c.buf.Len() {
- c.SetLoc(c.buf.Len())
- }
-}
-
-// SetLoc sets the location of the cursor in terms of character number
-// and not x, y location
-// It's just a simple wrapper of FromCharPos
-func (c *Cursor) SetLoc(loc int) {
- c.X, c.Y = FromCharPos(loc, c.buf)
- c.LastVisualX = c.GetVisualX()
-}
-
-// Loc gets the cursor location in terms of character number instead
-// of x, y location
-// It's just a simple wrapper of ToCharPos
-func (c *Cursor) Loc() int {
- return ToCharPos(c.X, c.Y, c.buf)
+// Goto puts the cursor at the given cursor's location and gives the current cursor its selection too
+func (c *Cursor) Goto(b Cursor) {
+ c.X, c.Y, c.LastVisualX = b.X, b.Y, b.LastVisualX
+ c.OrigSelection, c.CurSelection = b.OrigSelection, b.CurSelection
}
// ResetSelection resets the user's selection
func (c *Cursor) ResetSelection() {
- c.CurSelection[0] = 0
- c.CurSelection[1] = 0
+ c.CurSelection[0] = c.buf.Start()
+ c.CurSelection[1] = c.buf.Start()
}
// HasSelection returns whether or not the user has selected anything
// DeleteSelection deletes the currently selected text
func (c *Cursor) DeleteSelection() {
- if c.CurSelection[0] > c.CurSelection[1] {
+ if c.CurSelection[0].GreaterThan(c.CurSelection[1]) {
c.buf.Remove(c.CurSelection[1], c.CurSelection[0])
- c.SetLoc(c.CurSelection[1])
+ c.Loc = c.CurSelection[1]
} else if c.GetSelection() == "" {
return
} else {
c.buf.Remove(c.CurSelection[0], c.CurSelection[1])
- c.SetLoc(c.CurSelection[0])
+ c.Loc = c.CurSelection[0]
}
}
// GetSelection returns the cursor's selection
func (c *Cursor) GetSelection() string {
- if c.CurSelection[0] > c.CurSelection[1] {
+ if c.CurSelection[0].GreaterThan(c.CurSelection[1]) {
return c.buf.Substr(c.CurSelection[1], c.CurSelection[0])
}
return c.buf.Substr(c.CurSelection[0], c.CurSelection[1])
// SelectLine selects the current line
func (c *Cursor) SelectLine() {
c.Start()
- c.CurSelection[0] = c.Loc()
+ c.CurSelection[0] = c.Loc
c.End()
if c.buf.NumLines-1 > c.Y {
- c.CurSelection[1] = c.Loc() + 1
+ c.CurSelection[1] = c.Loc.Move(1, c.buf)
} else {
- c.CurSelection[1] = c.Loc()
+ c.CurSelection[1] = c.Loc
}
c.OrigSelection = c.CurSelection
// AddLineToSelection adds the current line to the selection
func (c *Cursor) AddLineToSelection() {
- loc := c.Loc()
-
- if loc < c.OrigSelection[0] {
+ if c.Loc.LessThan(c.OrigSelection[0]) {
c.Start()
- c.CurSelection[0] = c.Loc()
+ c.CurSelection[0] = c.Loc
c.CurSelection[1] = c.OrigSelection[1]
}
- if loc > c.OrigSelection[1] {
+ if c.Loc.GreaterThan(c.OrigSelection[1]) {
c.End()
- c.CurSelection[1] = c.Loc()
+ c.CurSelection[1] = c.Loc.Move(1, c.buf)
c.CurSelection[0] = c.OrigSelection[0]
}
- if loc < c.OrigSelection[1] && loc > c.OrigSelection[0] {
+ if c.Loc.LessThan(c.OrigSelection[1]) && c.Loc.GreaterThan(c.OrigSelection[0]) {
c.CurSelection = c.OrigSelection
}
}
// SelectWord selects the word the cursor is currently on
func (c *Cursor) SelectWord() {
- if len(c.buf.Lines[c.Y]) == 0 {
+ if len(c.buf.Line(c.Y)) == 0 {
return
}
if !IsWordChar(string(c.RuneUnder(c.X))) {
- loc := c.Loc()
- c.CurSelection[0] = loc
- c.CurSelection[1] = loc + 1
+ c.CurSelection[0] = c.Loc
+ c.CurSelection[1] = c.Loc.Move(1, c.buf)
c.OrigSelection = c.CurSelection
return
}
backward--
}
- c.CurSelection[0] = ToCharPos(backward, c.Y, c.buf)
+ c.CurSelection[0] = Loc{backward, c.Y}
c.OrigSelection[0] = c.CurSelection[0]
- for forward < Count(c.buf.Lines[c.Y])-1 && IsWordChar(string(c.RuneUnder(forward+1))) {
+ for forward < Count(c.buf.Line(c.Y))-1 && IsWordChar(string(c.RuneUnder(forward+1))) {
forward++
}
- c.CurSelection[1] = ToCharPos(forward, c.Y, c.buf) + 1
+ c.CurSelection[1] = Loc{forward, c.Y}.Move(1, c.buf)
c.OrigSelection[1] = c.CurSelection[1]
- c.SetLoc(c.CurSelection[1])
+ c.Loc = c.CurSelection[1]
}
// AddWordToSelection adds the word the cursor is currently on to the selection
func (c *Cursor) AddWordToSelection() {
- loc := c.Loc()
-
- if loc > c.OrigSelection[0] && loc < c.OrigSelection[1] {
+ if c.Loc.GreaterThan(c.OrigSelection[0]) && c.Loc.LessThan(c.OrigSelection[1]) {
c.CurSelection = c.OrigSelection
return
}
- if loc < c.OrigSelection[0] {
+ if c.Loc.LessThan(c.OrigSelection[0]) {
backward := c.X
for backward > 0 && IsWordChar(string(c.RuneUnder(backward-1))) {
backward--
}
- c.CurSelection[0] = ToCharPos(backward, c.Y, c.buf)
+ c.CurSelection[0] = Loc{backward, c.Y}
c.CurSelection[1] = c.OrigSelection[1]
}
- if loc > c.OrigSelection[1] {
+ if c.Loc.GreaterThan(c.OrigSelection[1]) {
forward := c.X
- for forward < Count(c.buf.Lines[c.Y])-1 && IsWordChar(string(c.RuneUnder(forward+1))) {
+ for forward < Count(c.buf.Line(c.Y))-1 && IsWordChar(string(c.RuneUnder(forward+1))) {
forward++
}
- c.CurSelection[1] = ToCharPos(forward, c.Y, c.buf) + 1
+ c.CurSelection[1] = Loc{forward, c.Y}.Move(1, c.buf)
c.CurSelection[0] = c.OrigSelection[0]
}
- c.SetLoc(c.CurSelection[1])
+ c.Loc = c.CurSelection[1]
}
// SelectTo selects from the current cursor location to the given location
-func (c *Cursor) SelectTo(loc int) {
- if loc > c.OrigSelection[0] {
+func (c *Cursor) SelectTo(loc Loc) {
+ if loc.GreaterThan(c.OrigSelection[0]) {
c.CurSelection[0] = c.OrigSelection[0]
c.CurSelection[1] = loc
} else {
func (c *Cursor) WordRight() {
c.Right()
for IsWhitespace(c.RuneUnder(c.X)) {
- if c.X == Count(c.buf.Lines[c.Y]) {
+ if c.X == Count(c.buf.Line(c.Y)) {
return
}
c.Right()
}
for !IsWhitespace(c.RuneUnder(c.X)) {
- if c.X == Count(c.buf.Lines[c.Y]) {
+ if c.X == Count(c.buf.Line(c.Y)) {
return
}
c.Right()
// RuneUnder returns the rune under the given x position
func (c *Cursor) RuneUnder(x int) rune {
- line := []rune(c.buf.Lines[c.Y])
+ line := []rune(c.buf.Line(c.Y))
if len(line) == 0 {
return '\n'
}
return line[x]
}
-// Up moves the cursor up one line (if possible)
-func (c *Cursor) Up() {
- if c.Y > 0 {
- c.Y--
+// UpN moves the cursor up N lines (if possible)
+func (c *Cursor) UpN(amount int) {
+ proposedY := c.Y - amount
+ if proposedY < 0 {
+ proposedY = 0
+ } else if proposedY >= c.buf.NumLines {
+ proposedY = c.buf.NumLines - 1
+ }
+ if proposedY == c.Y {
+ return
+ }
- runes := []rune(c.buf.Lines[c.Y])
- c.X = c.GetCharPosInLine(c.Y, c.LastVisualX)
- if c.X > len(runes) {
- c.X = len(runes)
- }
+ c.Y = proposedY
+ runes := []rune(c.buf.Line(c.Y))
+ c.X = c.GetCharPosInLine(c.Y, c.LastVisualX)
+ if c.X > len(runes) {
+ c.X = len(runes)
}
}
+// DownN moves the cursor down N lines (if possible)
+func (c *Cursor) DownN(amount int) {
+ c.UpN(-amount)
+}
+
+// Up moves the cursor up one line (if possible)
+func (c *Cursor) Up() {
+ c.UpN(1)
+}
+
// Down moves the cursor down one line (if possible)
func (c *Cursor) Down() {
- if c.Y < c.buf.NumLines-1 {
- c.Y++
-
- runes := []rune(c.buf.Lines[c.Y])
- c.X = c.GetCharPosInLine(c.Y, c.LastVisualX)
- if c.X > len(runes) {
- c.X = len(runes)
- }
- }
+ c.DownN(1)
}
// Left moves the cursor left one cell (if possible) or to the last line if it is at the beginning
func (c *Cursor) Left() {
- if c.Loc() == 0 {
+ if c.Loc == c.buf.Start() {
return
}
if c.X > 0 {
// Right moves the cursor right one cell (if possible) or to the next line if it is at the end
func (c *Cursor) Right() {
- if c.Loc() == c.buf.Len() {
+ if c.Loc == c.buf.End() {
return
}
- if c.X < Count(c.buf.Lines[c.Y]) {
+ if c.X < Count(c.buf.Line(c.Y)) {
c.X++
} else {
c.Down()
// End moves the cursor to the end of the line it is on
func (c *Cursor) End() {
- c.X = Count(c.buf.Lines[c.Y])
+ c.X = Count(c.buf.Line(c.Y))
c.LastVisualX = c.GetVisualX()
}
// Get the tab size
tabSize := int(settings["tabsize"].(float64))
// This is the visual line -- every \t replaced with the correct number of spaces
- visualLine := strings.Replace(c.buf.Lines[lineNum], "\t", "\t"+Spaces(tabSize-1), -1)
- if visualPos > Count(visualLine) {
- visualPos = Count(visualLine)
+ visualLineLen := StringWidth(c.buf.Line(lineNum))
+ if visualPos > visualLineLen {
+ visualPos = visualLineLen
}
- numTabs := NumOccurences(visualLine[:visualPos], '\t')
- if visualPos >= (tabSize-1)*numTabs {
- return visualPos - (tabSize-1)*numTabs
+ width := WidthOfLargeRunes(c.buf.Line(lineNum))
+ if visualPos >= width {
+ return visualPos - width
}
return visualPos / tabSize
}
// GetVisualX returns the x value of the cursor in visual spaces
func (c *Cursor) GetVisualX() int {
- runes := []rune(c.buf.Lines[c.Y])
- tabSize := int(settings["tabsize"].(float64))
- return c.X + NumOccurences(string(runes[:c.X]), '\t')*(tabSize-1)
+ runes := []rune(c.buf.Line(c.Y))
+ return StringWidth(string(runes[:c.X]))
}
// Relocate makes sure that the cursor is inside the bounds of the buffer
if c.X < 0 {
c.X = 0
- } else if c.X > Count(c.buf.Lines[c.Y]) {
- c.X = Count(c.buf.Lines[c.Y])
+ } else if c.X > Count(c.buf.Line(c.Y)) {
+ c.X = Count(c.buf.Line(c.Y))
}
}