termui: use a forked gocui to fix large character handling

1 files changed, 504 insertions, 0 deletions

diff --git a/vendor/github.com/MichaelMure/gocui/view.go b/vendor/github.com/MichaelMure/gocui/view.go
new file mode 100644
index 00000000..d7943497
--- /dev/null
+++ b/vendor/github.com/MichaelMure/gocui/view.go
@@ -0,0 +1,504 @@
+// Copyright 2014 The gocui Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gocui
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"strings"
+
+	"github.com/mattn/go-runewidth"
+	"github.com/nsf/termbox-go"
+)
+
+// A View is a window. It maintains its own internal buffer and cursor
+// position.
+type View struct {
+	name           string
+	x0, y0, x1, y1 int
+	ox, oy         int
+	cx, cy         int
+	lines          [][]cell
+	readOffset     int
+	readCache      string
+
+	tainted   bool       // marks if the viewBuffer must be updated
+	viewLines []viewLine // internal representation of the view's buffer
+
+	ei *escapeInterpreter // used to decode ESC sequences on Write
+
+	// BgColor and FgColor allow to configure the background and foreground
+	// colors of the View.
+	BgColor, FgColor Attribute
+
+	// SelBgColor and SelFgColor are used to configure the background and
+	// foreground colors of the selected line, when it is highlighted.
+	SelBgColor, SelFgColor Attribute
+
+	// If Editable is true, keystrokes will be added to the view's internal
+	// buffer at the cursor position.
+	Editable bool
+
+	// Editor allows to define the editor that manages the edition mode,
+	// including keybindings or cursor behaviour. DefaultEditor is used by
+	// default.
+	Editor Editor
+
+	// Overwrite enables or disables the overwrite mode of the view.
+	Overwrite bool
+
+	// If Highlight is true, Sel{Bg,Fg}Colors will be used
+	// for the line under the cursor position.
+	Highlight bool
+
+	// If Frame is true, a border will be drawn around the view.
+	Frame bool
+
+	// If Wrap is true, the content that is written to this View is
+	// automatically wrapped when it is longer than its width. If true the
+	// view's x-origin will be ignored.
+	Wrap bool
+
+	// If Autoscroll is true, the View will automatically scroll down when the
+	// text overflows. If true the view's y-origin will be ignored.
+	Autoscroll bool
+
+	// If Frame is true, Title allows to configure a title for the view.
+	Title string
+
+	// If Mask is true, the View will display the mask instead of the real
+	// content
+	Mask rune
+}
+
+type viewLine struct {
+	linesX, linesY int // coordinates relative to v.lines
+	line           []cell
+}
+
+type cell struct {
+	chr              rune
+	bgColor, fgColor Attribute
+}
+
+type lineType []cell
+
+// String returns a string from a given cell slice.
+func (l lineType) String() string {
+	str := ""
+	for _, c := range l {
+		str += string(c.chr)
+	}
+	return str
+}
+
+// newView returns a new View object.
+func newView(name string, x0, y0, x1, y1 int, mode OutputMode) *View {
+	v := &View{
+		name:    name,
+		x0:      x0,
+		y0:      y0,
+		x1:      x1,
+		y1:      y1,
+		Frame:   true,
+		Editor:  DefaultEditor,
+		tainted: true,
+		ei:      newEscapeInterpreter(mode),
+	}
+	return v
+}
+
+// Size returns the number of visible columns and rows in the View.
+func (v *View) Size() (x, y int) {
+	return v.x1 - v.x0 - 1, v.y1 - v.y0 - 1
+}
+
+// Name returns the name of the view.
+func (v *View) Name() string {
+	return v.name
+}
+
+// setRune sets a rune at the given point relative to the view. It applies the
+// specified colors, taking into account if the cell must be highlighted. Also,
+// it checks if the position is valid.
+func (v *View) setRune(x, y int, ch rune, fgColor, bgColor Attribute) error {
+	maxX, maxY := v.Size()
+	if x < 0 || x >= maxX || y < 0 || y >= maxY {
+		return errors.New("invalid point")
+	}
+
+	var (
+		ry, rcy int
+		err     error
+	)
+	if v.Highlight {
+		_, ry, err = v.realPosition(x, y)
+		if err != nil {
+			return err
+		}
+		_, rcy, err = v.realPosition(v.cx, v.cy)
+		if err != nil {
+			return err
+		}
+	}
+
+	if v.Mask != 0 {
+		fgColor = v.FgColor
+		bgColor = v.BgColor
+		ch = v.Mask
+	} else if v.Highlight && ry == rcy {
+		fgColor = v.SelFgColor
+		bgColor = v.SelBgColor
+	}
+
+	termbox.SetCell(v.x0+x+1, v.y0+y+1, ch,
+		termbox.Attribute(fgColor), termbox.Attribute(bgColor))
+
+	return nil
+}
+
+// SetCursor sets the cursor position of the view at the given point,
+// relative to the view. It checks if the position is valid.
+func (v *View) SetCursor(x, y int) error {
+	maxX, maxY := v.Size()
+	if x < 0 || x >= maxX || y < 0 || y >= maxY {
+		return errors.New("invalid point")
+	}
+	v.cx = x
+	v.cy = y
+	return nil
+}
+
+// Cursor returns the cursor position of the view.
+func (v *View) Cursor() (x, y int) {
+	return v.cx, v.cy
+}
+
+// SetOrigin sets the origin position of the view's internal buffer,
+// so the buffer starts to be printed from this point, which means that
+// it is linked with the origin point of view. It can be used to
+// implement Horizontal and Vertical scrolling with just incrementing
+// or decrementing ox and oy.
+func (v *View) SetOrigin(x, y int) error {
+	if x < 0 || y < 0 {
+		return errors.New("invalid point")
+	}
+	v.ox = x
+	v.oy = y
+	return nil
+}
+
+// Origin returns the origin position of the view.
+func (v *View) Origin() (x, y int) {
+	return v.ox, v.oy
+}
+
+// Write appends a byte slice into the view's internal buffer. Because
+// View implements the io.Writer interface, it can be passed as parameter
+// of functions like fmt.Fprintf, fmt.Fprintln, io.Copy, etc. Clear must
+// be called to clear the view's buffer.
+func (v *View) Write(p []byte) (n int, err error) {
+	v.tainted = true
+
+	for _, ch := range bytes.Runes(p) {
+		switch ch {
+		case '\n':
+			v.lines = append(v.lines, nil)
+		case '\r':
+			nl := len(v.lines)
+			if nl > 0 {
+				v.lines[nl-1] = nil
+			} else {
+				v.lines = make([][]cell, 1)
+			}
+		default:
+			cells := v.parseInput(ch)
+			if cells == nil {
+				continue
+			}
+
+			nl := len(v.lines)
+			if nl > 0 {
+				v.lines[nl-1] = append(v.lines[nl-1], cells...)
+			} else {
+				v.lines = append(v.lines, cells)
+			}
+		}
+	}
+	return len(p), nil
+}
+
+// parseInput parses char by char the input written to the View. It returns nil
+// while processing ESC sequences. Otherwise, it returns a cell slice that
+// contains the processed data.
+func (v *View) parseInput(ch rune) []cell {
+	cells := []cell{}
+
+	isEscape, err := v.ei.parseOne(ch)
+	if err != nil {
+		for _, r := range v.ei.runes() {
+			c := cell{
+				fgColor: v.FgColor,
+				bgColor: v.BgColor,
+				chr:     r,
+			}
+			cells = append(cells, c)
+		}
+		v.ei.reset()
+	} else {
+		if isEscape {
+			return nil
+		}
+		c := cell{
+			fgColor: v.ei.curFgColor,
+			bgColor: v.ei.curBgColor,
+			chr:     ch,
+		}
+		cells = append(cells, c)
+	}
+
+	return cells
+}
+
+// Read reads data into p. It returns the number of bytes read into p.
+// At EOF, err will be io.EOF. Calling Read() after Rewind() makes the
+// cache to be refreshed with the contents of the view.
+func (v *View) Read(p []byte) (n int, err error) {
+	if v.readOffset == 0 {
+		v.readCache = v.Buffer()
+	}
+	if v.readOffset < len(v.readCache) {
+		n = copy(p, v.readCache[v.readOffset:])
+		v.readOffset += n
+	} else {
+		err = io.EOF
+	}
+	return
+}
+
+// Rewind sets the offset for the next Read to 0, which also refresh the
+// read cache.
+func (v *View) Rewind() {
+	v.readOffset = 0
+}
+
+// draw re-draws the view's contents.
+func (v *View) draw() error {
+	maxX, maxY := v.Size()
+
+	if v.Wrap {
+		if maxX == 0 {
+			return errors.New("X size of the view cannot be 0")
+		}
+		v.ox = 0
+	}
+	if v.tainted {
+		v.viewLines = nil
+		for i, line := range v.lines {
+			if v.Wrap {
+				if len(line) < maxX {
+					vline := viewLine{linesX: 0, linesY: i, line: line}
+					v.viewLines = append(v.viewLines, vline)
+					continue
+				} else {
+					for n := 0; n <= len(line); n += maxX {
+						if len(line[n:]) <= maxX {
+							vline := viewLine{linesX: n, linesY: i, line: line[n:]}
+							v.viewLines = append(v.viewLines, vline)
+						} else {
+							vline := viewLine{linesX: n, linesY: i, line: line[n : n+maxX]}
+							v.viewLines = append(v.viewLines, vline)
+						}
+					}
+				}
+			} else {
+				vline := viewLine{linesX: 0, linesY: i, line: line}
+				v.viewLines = append(v.viewLines, vline)
+			}
+		}
+		v.tainted = false
+	}
+
+	if v.Autoscroll && len(v.viewLines) > maxY {
+		v.oy = len(v.viewLines) - maxY
+	}
+	y := 0
+	for i, vline := range v.viewLines {
+		if i < v.oy {
+			continue
+		}
+		if y >= maxY {
+			break
+		}
+		x := 0
+		for j, c := range vline.line {
+			if j < v.ox {
+				continue
+			}
+			if x >= maxX {
+				break
+			}
+
+			fgColor := c.fgColor
+			if fgColor == ColorDefault {
+				fgColor = v.FgColor
+			}
+			bgColor := c.bgColor
+			if bgColor == ColorDefault {
+				bgColor = v.BgColor
+			}
+
+			if err := v.setRune(x, y, c.chr, fgColor, bgColor); err != nil {
+				return err
+			}
+			x += runewidth.RuneWidth(c.chr)
+		}
+		y++
+	}
+	return nil
+}
+
+// realPosition returns the position in the internal buffer corresponding to the
+// point (x, y) of the view.
+func (v *View) realPosition(vx, vy int) (x, y int, err error) {
+	vx = v.ox + vx
+	vy = v.oy + vy
+
+	if vx < 0 || vy < 0 {
+		return 0, 0, errors.New("invalid point")
+	}
+
+	if len(v.viewLines) == 0 {
+		return vx, vy, nil
+	}
+
+	if vy < len(v.viewLines) {
+		vline := v.viewLines[vy]
+		x = vline.linesX + vx
+		y = vline.linesY
+	} else {
+		vline := v.viewLines[len(v.viewLines)-1]
+		x = vx
+		y = vline.linesY + vy - len(v.viewLines) + 1
+	}
+
+	return x, y, nil
+}
+
+// Clear empties the view's internal buffer.
+func (v *View) Clear() {
+	v.tainted = true
+
+	v.lines = nil
+	v.viewLines = nil
+	v.readOffset = 0
+	v.clearRunes()
+}
+
+// clearRunes erases all the cells in the view.
+func (v *View) clearRunes() {
+	maxX, maxY := v.Size()
+	for x := 0; x < maxX; x++ {
+		for y := 0; y < maxY; y++ {
+			termbox.SetCell(v.x0+x+1, v.y0+y+1, ' ',
+				termbox.Attribute(v.FgColor), termbox.Attribute(v.BgColor))
+		}
+	}
+}
+
+// BufferLines returns the lines in the view's internal
+// buffer.
+func (v *View) BufferLines() []string {
+	lines := make([]string, len(v.lines))
+	for i, l := range v.lines {
+		str := lineType(l).String()
+		str = strings.Replace(str, "\x00", " ", -1)
+		lines[i] = str
+	}
+	return lines
+}
+
+// Buffer returns a string with the contents of the view's internal
+// buffer.
+func (v *View) Buffer() string {
+	str := ""
+	for _, l := range v.lines {
+		str += lineType(l).String() + "\n"
+	}
+	return strings.Replace(str, "\x00", " ", -1)
+}
+
+// ViewBufferLines returns the lines in the view's internal
+// buffer that is shown to the user.
+func (v *View) ViewBufferLines() []string {
+	lines := make([]string, len(v.viewLines))
+	for i, l := range v.viewLines {
+		str := lineType(l.line).String()
+		str = strings.Replace(str, "\x00", " ", -1)
+		lines[i] = str
+	}
+	return lines
+}
+
+// ViewBuffer returns a string with the contents of the view's buffer that is
+// shown to the user.
+func (v *View) ViewBuffer() string {
+	str := ""
+	for _, l := range v.viewLines {
+		str += lineType(l.line).String() + "\n"
+	}
+	return strings.Replace(str, "\x00", " ", -1)
+}
+
+// Line returns a string with the line of the view's internal buffer
+// at the position corresponding to the point (x, y).
+func (v *View) Line(y int) (string, error) {
+	_, y, err := v.realPosition(0, y)
+	if err != nil {
+		return "", err
+	}
+
+	if y < 0 || y >= len(v.lines) {
+		return "", errors.New("invalid point")
+	}
+
+	return lineType(v.lines[y]).String(), nil
+}
+
+// Word returns a string with the word of the view's internal buffer
+// at the position corresponding to the point (x, y).
+func (v *View) Word(x, y int) (string, error) {
+	x, y, err := v.realPosition(x, y)
+	if err != nil {
+		return "", err
+	}
+
+	if x < 0 || y < 0 || y >= len(v.lines) || x >= len(v.lines[y]) {
+		return "", errors.New("invalid point")
+	}
+
+	str := lineType(v.lines[y]).String()
+
+	nl := strings.LastIndexFunc(str[:x], indexFunc)
+	if nl == -1 {
+		nl = 0
+	} else {
+		nl = nl + 1
+	}
+	nr := strings.IndexFunc(str[x:], indexFunc)
+	if nr == -1 {
+		nr = len(str)
+	} else {
+		nr = nr + x
+	}
+	return string(str[nl:nr]), nil
+}
+
+// indexFunc allows to split lines by words taking into account spaces
+// and 0.
+func indexFunc(r rune) bool {
+	return r == ' ' || r == 0
+}