buffer: Remove data as structure element of Line

internal/buffer/line_array.go

@@ -10,28 +10,6 @@ import (
 	"github.com/micro-editor/micro/v2/pkg/highlight"
 )
 
-// Finds the byte index of the nth rune in a byte slice
-func runeToByteIndex(n int, txt []byte) int {
-	if n == 0 {
-		return 0
-	}
-
-	count := 0
-	i := 0
-	for len(txt) > 0 {
-		_, _, size := util.DecodeCharacter(txt)
-
-		txt = txt[size:]
-		count += size
-		i++
-
-		if i == n {
-			break
-		}
-	}
-	return count
-}
-
 // A searchState contains the search match info for a single line
 type searchState struct {
 	search     string
@@ -41,10 +19,9 @@ type searchState struct {
 	done       bool
 }
 
-// A Line contains the data in bytes as well as a highlight state, match
+// A Line contains the slice of runes as well as a highlight state, match
 // and a flag for whether the highlighting needs to be updated
 type Line struct {
-	data  []byte
 	runes []rune
 
 	state highlight.State
@@ -60,6 +37,10 @@ type Line struct {
 	search map[*Buffer]*searchState
 }
 
+func (l Line) data() []byte {
+	return []byte(string(l.runes))
+}
+
 const (
 	// Line ending file formats
 	FFAuto = 0 // Autodetect format
@@ -95,7 +76,7 @@ func Append(slice []Line, data ...Line) []Line {
 	return slice
 }
 
-// NewLineArray returns a new line array from an array of bytes
+// NewLineArray returns a new line array from an array of runes
 func NewLineArray(size uint64, endings FileFormat, reader io.Reader) *LineArray {
 	la := new(LineArray)
 
@@ -149,7 +130,6 @@ func NewLineArray(size uint64, endings FileFormat, reader io.Reader) *LineArray
 			if err == io.EOF {
 				runes, _ := util.DecodeCharacters(data)
 				la.lines = Append(la.lines, Line{
-					data:  data,
 					runes: runes,
 					state: nil,
 					match: nil,
@@ -160,7 +140,6 @@ func NewLineArray(size uint64, endings FileFormat, reader io.Reader) *LineArray
 		} else {
 			runes, _ := util.DecodeCharacters(data[:dlen-1])
 			la.lines = Append(la.lines, Line{
-				data:  data[:dlen-1],
 				runes: runes,
 				state: nil,
 				match: nil,
@@ -179,7 +158,7 @@ func (la *LineArray) Bytes() []byte {
 	// initsize should provide a good estimate
 	b.Grow(int(la.initsize + 4096))
 	for i, l := range la.lines {
-		b.Write(l.data)
+		b.Write(l.data())
 		if i != len(la.lines)-1 {
 			if la.Endings == FFDos {
 				b.WriteByte('\r')
@@ -193,14 +172,12 @@ func (la *LineArray) Bytes() []byte {
 // newlineBelow adds a newline below the given line number
 func (la *LineArray) newlineBelow(y int) {
 	la.lines = append(la.lines, Line{
-		data:  []byte{' '},
 		runes: []rune{},
 		state: nil,
 		match: nil,
 	})
 	copy(la.lines[y+2:], la.lines[y+1:])
 	la.lines[y+1] = Line{
-		data:  []byte{},
 		runes: []rune{},
 		state: la.lines[y].state,
 		match: nil,
@@ -212,41 +189,57 @@ func (la *LineArray) insert(pos Loc, value []byte) {
 	la.lock.Lock()
 	defer la.lock.Unlock()
 
-	x, y := runeToByteIndex(pos.X, la.lines[pos.Y].data), pos.Y
-	for i := 0; i < len(value); i++ {
-		if value[i] == '\n' || (value[i] == '\r' && i < len(value)-1 && value[i+1] == '\n') {
+	runes, _ := util.DecodeCharacters(value)
+	x, y := util.Min(pos.X, len(la.lines[pos.Y].runes)), pos.Y
+	start := -1
+	for i := 0; i < len(runes); i++ {
+		if runes[i] == '\n' || (runes[i] == '\r' && i < len(runes)-1 && runes[i+1] == '\n') {
 			la.split(Loc{x, y})
+			if i > 0 && start < len(runes) && start < i {
+				if start < 0 {
+					start = 0
+				}
+				la.insertRunes(Loc{x, y}, runes[start:i])
+			}
+
 			x = 0
 			y++
 
-			if value[i] == '\r' {
+			if runes[i] == '\r' {
 				i++
 			}
+			if i+1 <= len(runes) {
+
+				start = i + 1
+			}
 
 			continue
 		}
-		la.insertByte(Loc{x, y}, value[i])
-		x++
+	}
+	if start < 0 {
+		la.insertRunes(Loc{x, y}, runes)
+	} else if start < len(runes) {
+		la.insertRunes(Loc{x, y}, runes[start:])
 	}
 }
 
-// InsertByte inserts a byte at a given location
-func (la *LineArray) insertByte(pos Loc, value byte) {
-	la.lines[pos.Y].data = append(la.lines[pos.Y].data, 0)
-	copy(la.lines[pos.Y].data[pos.X+1:], la.lines[pos.Y].data[pos.X:])
-	la.lines[pos.Y].data[pos.X] = value
+// Inserts a rune array at a given location
+func (la *LineArray) insertRunes(pos Loc, runes []rune) {
+	la.lines[pos.Y].runes = append(la.lines[pos.Y].runes, runes...)
+	copy(la.lines[pos.Y].runes[pos.X+len(runes):], la.lines[pos.Y].runes[pos.X:])
+	copy(la.lines[pos.Y].runes[pos.X:], runes)
 }
 
 // joinLines joins the two lines a and b
 func (la *LineArray) joinLines(a, b int) {
-	la.lines[a].data = append(la.lines[a].data, la.lines[b].data...)
+	la.insertRunes(Loc{len(la.lines[a].runes), a}, la.lines[b].runes)
 	la.deleteLine(b)
 }
 
 // split splits a line at a given position
 func (la *LineArray) split(pos Loc) {
 	la.newlineBelow(pos.Y)
-	la.lines[pos.Y+1].data = append(la.lines[pos.Y+1].data, la.lines[pos.Y].data[pos.X:]...)
+	la.insertRunes(Loc{0, pos.Y + 1}, la.lines[pos.Y].runes[pos.X:])
 	la.lines[pos.Y+1].state = la.lines[pos.Y].state
 	la.lines[pos.Y].state = nil
 	la.lines[pos.Y].match = nil
@@ -260,10 +253,10 @@ func (la *LineArray) remove(start, end Loc) []byte {
 	defer la.lock.Unlock()
 
 	sub := la.Substr(start, end)
-	startX := runeToByteIndex(start.X, la.lines[start.Y].data)
-	endX := runeToByteIndex(end.X, la.lines[end.Y].data)
+	startX := util.Min(start.X, len(la.lines[start.Y].runes))
+	endX := util.Min(end.X, len(la.lines[end.Y].runes))
 	if start.Y == end.Y {
-		la.lines[start.Y].data = append(la.lines[start.Y].data[:startX], la.lines[start.Y].data[endX:]...)
+		la.lines[start.Y].runes = append(la.lines[start.Y].runes[:startX], la.lines[start.Y].runes[endX:]...)
 	} else {
 		la.deleteLines(start.Y+1, end.Y-1)
 		la.deleteToEnd(Loc{startX, start.Y})
@@ -275,12 +268,12 @@ func (la *LineArray) remove(start, end Loc) []byte {
 
 // deleteToEnd deletes from the end of a line to the position
 func (la *LineArray) deleteToEnd(pos Loc) {
-	la.lines[pos.Y].data = la.lines[pos.Y].data[:pos.X]
+	la.lines[pos.Y].runes = la.lines[pos.Y].runes[:pos.X]
 }
 
 // deleteFromStart deletes from the start of a line to the position
 func (la *LineArray) deleteFromStart(pos Loc) {
-	la.lines[pos.Y].data = la.lines[pos.Y].data[pos.X+1:]
+	la.lines[pos.Y].runes = la.lines[pos.Y].runes[pos.X+1:]
 }
 
 // deleteLine deletes the line number
@@ -294,22 +287,19 @@ func (la *LineArray) deleteLines(y1, y2 int) {
 
 // Substr returns the string representation between two locations
 func (la *LineArray) Substr(start, end Loc) []byte {
-	startX := runeToByteIndex(start.X, la.lines[start.Y].data)
-	endX := runeToByteIndex(end.X, la.lines[end.Y].data)
-	if start.Y == end.Y {
-		src := la.lines[start.Y].data[startX:endX]
-		dest := make([]byte, len(src))
-		copy(dest, src)
-		return dest
+	startX := util.Min(start.X, len(la.lines[start.Y].runes))
+	endX := util.Min(end.X, len(la.lines[end.Y].runes))
+	if start.Y == end.Y && startX <= endX {
+		return []byte(string(la.lines[start.Y].runes[startX:endX]))
 	}
-	str := make([]byte, 0, len(la.lines[start.Y+1].data)*(end.Y-start.Y))
-	str = append(str, la.lines[start.Y].data[startX:]...)
+	var str []byte
+	str = append(str, []byte(string(la.lines[start.Y].runes[startX:]))...)
 	str = append(str, '\n')
 	for i := start.Y + 1; i <= end.Y-1; i++ {
-		str = append(str, la.lines[i].data...)
+		str = append(str, []byte(string(la.lines[i].runes))...)
 		str = append(str, '\n')
 	}
-	str = append(str, la.lines[end.Y].data[:endX]...)
+	str = append(str, []byte(string(la.lines[end.Y].runes[:endX]))...)
 	return str
 }
 
@@ -326,15 +316,31 @@ func (la *LineArray) Start() Loc {
 // End returns the location of the last character in the buffer
 func (la *LineArray) End() Loc {
 	numlines := len(la.lines)
-	return Loc{util.CharacterCount(la.lines[numlines-1].data), numlines - 1}
+	return Loc{len(la.lines[numlines-1].runes), numlines - 1}
+}
+
+// Line returns line n as an array of runes
+func (la *LineArray) Line(n int) []rune {
+	if n >= len(la.lines) || n < 0 {
+		return []rune{}
+	}
+	return la.lines[n].runes
 }
 
 // LineBytes returns line n as an array of bytes
-func (la *LineArray) LineBytes(lineN int) []byte {
-	if lineN >= len(la.lines) || lineN < 0 {
+func (la *LineArray) LineBytes(n int) []byte {
+	if n >= len(la.lines) || n < 0 {
 		return []byte{}
 	}
-	return la.lines[lineN].data
+	return []byte(string(la.lines[n].runes))
+}
+
+// LineString returns line n as an string
+func (la *LineArray) LineString(n int) string {
+	if n >= len(la.lines) || n < 0 {
+		return string("")
+	}
+	return string(la.lines[n].runes)
 }
 
 // State gets the highlight state for the given line number
@@ -416,7 +422,7 @@ func (la *LineArray) SearchMatch(b *Buffer, pos Loc) bool {
 	if !s.done {
 		s.match = nil
 		start := Loc{0, lineN}
-		end := Loc{util.CharacterCount(la.lines[lineN].data), lineN}
+		end := Loc{len(la.lines[lineN].runes), lineN}
 		for start.X < end.X {
 			m, found, _ := b.FindNext(b.LastSearch, start, end, start, true, b.LastSearchRegex)
 			if !found {