1 files changed, 329 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/gizak/termui/linechart.go b/Godeps/_workspace/src/github.com/gizak/termui/linechart.go
new file mode 100644
index 000000000..f2829148e
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/gizak/termui/linechart.go
@@ -0,0 +1,329 @@
+// Copyright 2016 Zack Guo <gizak@icloud.com>. All rights reserved.
+// Use of this source code is governed by a MIT license that can
+// be found in the LICENSE file.
+
+package termui
+
+import (
+	"fmt"
+	"math"
+)
+
+// only 16 possible combinations, why bother
+var braillePatterns = map[[2]int]rune{
+	[2]int{0, 0}: '⣀',
+	[2]int{0, 1}: '⡠',
+	[2]int{0, 2}: '⡐',
+	[2]int{0, 3}: '⡈',
+
+	[2]int{1, 0}: '⢄',
+	[2]int{1, 1}: '⠤',
+	[2]int{1, 2}: '⠔',
+	[2]int{1, 3}: '⠌',
+
+	[2]int{2, 0}: '⢂',
+	[2]int{2, 1}: '⠢',
+	[2]int{2, 2}: '⠒',
+	[2]int{2, 3}: '⠊',
+
+	[2]int{3, 0}: '⢁',
+	[2]int{3, 1}: '⠡',
+	[2]int{3, 2}: '⠑',
+	[2]int{3, 3}: '⠉',
+}
+
+var lSingleBraille = [4]rune{'\u2840', '⠄', '⠂', '⠁'}
+var rSingleBraille = [4]rune{'\u2880', '⠠', '⠐', '⠈'}
+
+// LineChart has two modes: braille(default) and dot. Using braille gives 2x capicity as dot mode,
+// because one braille char can represent two data points.
+/*
+  lc := termui.NewLineChart()
+  lc.Border.Label = "braille-mode Line Chart"
+  lc.Data = [1.2, 1.3, 1.5, 1.7, 1.5, 1.6, 1.8, 2.0]
+  lc.Width = 50
+  lc.Height = 12
+  lc.AxesColor = termui.ColorWhite
+  lc.LineColor = termui.ColorGreen | termui.AttrBold
+  // termui.Render(lc)...
+*/
+type LineChart struct {
+	Block
+	Data          []float64
+	DataLabels    []string // if unset, the data indices will be used
+	Mode          string   // braille | dot
+	DotStyle      rune
+	LineColor     Attribute
+	scale         float64 // data span per cell on y-axis
+	AxesColor     Attribute
+	drawingX      int
+	drawingY      int
+	axisYHeight   int
+	axisXWidth    int
+	axisYLebelGap int
+	axisXLebelGap int
+	topValue      float64
+	bottomValue   float64
+	labelX        [][]rune
+	labelY        [][]rune
+	labelYSpace   int
+	maxY          float64
+	minY          float64
+}
+
+// NewLineChart returns a new LineChart with current theme.
+func NewLineChart() *LineChart {
+	lc := &LineChart{Block: *NewBlock()}
+	lc.AxesColor = ThemeAttr("linechart.axes.fg")
+	lc.LineColor = ThemeAttr("linechart.line.fg")
+	lc.Mode = "braille"
+	lc.DotStyle = '•'
+	lc.axisXLebelGap = 2
+	lc.axisYLebelGap = 1
+	lc.bottomValue = math.Inf(1)
+	lc.topValue = math.Inf(-1)
+	return lc
+}
+
+// one cell contains two data points
+// so the capicity is 2x as dot-mode
+func (lc *LineChart) renderBraille() Buffer {
+	buf := NewBuffer()
+
+	// return: b -> which cell should the point be in
+	//         m -> in the cell, divided into 4 equal height levels, which subcell?
+	getPos := func(d float64) (b, m int) {
+		cnt4 := int((d-lc.bottomValue)/(lc.scale/4) + 0.5)
+		b = cnt4 / 4
+		m = cnt4 % 4
+		return
+	}
+	// plot points
+	for i := 0; 2*i+1 < len(lc.Data) && i < lc.axisXWidth; i++ {
+		b0, m0 := getPos(lc.Data[2*i])
+		b1, m1 := getPos(lc.Data[2*i+1])
+
+		if b0 == b1 {
+			c := Cell{
+				Ch: braillePatterns[[2]int{m0, m1}],
+				Bg: lc.Bg,
+				Fg: lc.LineColor,
+			}
+			y := lc.innerArea.Min.Y + lc.innerArea.Dy() - 3 - b0
+			x := lc.innerArea.Min.X + lc.labelYSpace + 1 + i
+			buf.Set(x, y, c)
+		} else {
+			c0 := Cell{Ch: lSingleBraille[m0],
+				Fg: lc.LineColor,
+				Bg: lc.Bg}
+			x0 := lc.innerArea.Min.X + lc.labelYSpace + 1 + i
+			y0 := lc.innerArea.Min.Y + lc.innerArea.Dy() - 3 - b0
+			buf.Set(x0, y0, c0)
+
+			c1 := Cell{Ch: rSingleBraille[m1],
+				Fg: lc.LineColor,
+				Bg: lc.Bg}
+			x1 := lc.innerArea.Min.X + lc.labelYSpace + 1 + i
+			y1 := lc.innerArea.Min.Y + lc.innerArea.Dy() - 3 - b1
+			buf.Set(x1, y1, c1)
+		}
+
+	}
+	return buf
+}
+
+func (lc *LineChart) renderDot() Buffer {
+	buf := NewBuffer()
+	for i := 0; i < len(lc.Data) && i < lc.axisXWidth; i++ {
+		c := Cell{
+			Ch: lc.DotStyle,
+			Fg: lc.LineColor,
+			Bg: lc.Bg,
+		}
+		x := lc.innerArea.Min.X + lc.labelYSpace + 1 + i
+		y := lc.innerArea.Min.Y + lc.innerArea.Dy() - 3 - int((lc.Data[i]-lc.bottomValue)/lc.scale+0.5)
+		buf.Set(x, y, c)
+	}
+
+	return buf
+}
+
+func (lc *LineChart) calcLabelX() {
+	lc.labelX = [][]rune{}
+
+	for i, l := 0, 0; i < len(lc.DataLabels) && l < lc.axisXWidth; i++ {
+		if lc.Mode == "dot" {
+			if l >= len(lc.DataLabels) {
+				break
+			}
+
+			s := str2runes(lc.DataLabels[l])
+			w := strWidth(lc.DataLabels[l])
+			if l+w <= lc.axisXWidth {
+				lc.labelX = append(lc.labelX, s)
+			}
+			l += w + lc.axisXLebelGap
+		} else { // braille
+			if 2*l >= len(lc.DataLabels) {
+				break
+			}
+
+			s := str2runes(lc.DataLabels[2*l])
+			w := strWidth(lc.DataLabels[2*l])
+			if l+w <= lc.axisXWidth {
+				lc.labelX = append(lc.labelX, s)
+			}
+			l += w + lc.axisXLebelGap
+
+		}
+	}
+}
+
+func shortenFloatVal(x float64) string {
+	s := fmt.Sprintf("%.2f", x)
+	if len(s)-3 > 3 {
+		s = fmt.Sprintf("%.2e", x)
+	}
+
+	if x < 0 {
+		s = fmt.Sprintf("%.2f", x)
+	}
+	return s
+}
+
+func (lc *LineChart) calcLabelY() {
+	span := lc.topValue - lc.bottomValue
+	lc.scale = span / float64(lc.axisYHeight)
+
+	n := (1 + lc.axisYHeight) / (lc.axisYLebelGap + 1)
+	lc.labelY = make([][]rune, n)
+	maxLen := 0
+	for i := 0; i < n; i++ {
+		s := str2runes(shortenFloatVal(lc.bottomValue + float64(i)*span/float64(n)))
+		if len(s) > maxLen {
+			maxLen = len(s)
+		}
+		lc.labelY[i] = s
+	}
+
+	lc.labelYSpace = maxLen
+}
+
+func (lc *LineChart) calcLayout() {
+	// set datalabels if it is not provided
+	if lc.DataLabels == nil || len(lc.DataLabels) == 0 {
+		lc.DataLabels = make([]string, len(lc.Data))
+		for i := range lc.Data {
+			lc.DataLabels[i] = fmt.Sprint(i)
+		}
+	}
+
+	// lazy increase, to avoid y shaking frequently
+	// update bound Y when drawing is gonna overflow
+	lc.minY = lc.Data[0]
+	lc.maxY = lc.Data[0]
+
+	// valid visible range
+	vrange := lc.innerArea.Dx()
+	if lc.Mode == "braille" {
+		vrange = 2 * lc.innerArea.Dx()
+	}
+	if vrange > len(lc.Data) {
+		vrange = len(lc.Data)
+	}
+
+	for _, v := range lc.Data[:vrange] {
+		if v > lc.maxY {
+			lc.maxY = v
+		}
+		if v < lc.minY {
+			lc.minY = v
+		}
+	}
+
+	span := lc.maxY - lc.minY
+
+	if lc.minY < lc.bottomValue {
+		lc.bottomValue = lc.minY - 0.2*span
+	}
+
+	if lc.maxY > lc.topValue {
+		lc.topValue = lc.maxY + 0.2*span
+	}
+
+	lc.axisYHeight = lc.innerArea.Dy() - 2
+	lc.calcLabelY()
+
+	lc.axisXWidth = lc.innerArea.Dx() - 1 - lc.labelYSpace
+	lc.calcLabelX()
+
+	lc.drawingX = lc.innerArea.Min.X + 1 + lc.labelYSpace
+	lc.drawingY = lc.innerArea.Min.Y
+}
+
+func (lc *LineChart) plotAxes() Buffer {
+	buf := NewBuffer()
+
+	origY := lc.innerArea.Min.Y + lc.innerArea.Dy() - 2
+	origX := lc.innerArea.Min.X + lc.labelYSpace
+
+	buf.Set(origX, origY, Cell{Ch: ORIGIN, Fg: lc.AxesColor, Bg: lc.Bg})
+
+	for x := origX + 1; x < origX+lc.axisXWidth; x++ {
+		buf.Set(x, origY, Cell{Ch: HDASH, Fg: lc.AxesColor, Bg: lc.Bg})
+	}
+
+	for dy := 1; dy <= lc.axisYHeight; dy++ {
+		buf.Set(origX, origY-dy, Cell{Ch: VDASH, Fg: lc.AxesColor, Bg: lc.Bg})
+	}
+
+	// x label
+	oft := 0
+	for _, rs := range lc.labelX {
+		if oft+len(rs) > lc.axisXWidth {
+			break
+		}
+		for j, r := range rs {
+			c := Cell{
+				Ch: r,
+				Fg: lc.AxesColor,
+				Bg: lc.Bg,
+			}
+			x := origX + oft + j
+			y := lc.innerArea.Min.Y + lc.innerArea.Dy() - 1
+			buf.Set(x, y, c)
+		}
+		oft += len(rs) + lc.axisXLebelGap
+	}
+
+	// y labels
+	for i, rs := range lc.labelY {
+		for j, r := range rs {
+			buf.Set(
+				lc.innerArea.Min.X+j,
+				origY-i*(lc.axisYLebelGap+1),
+				Cell{Ch: r, Fg: lc.AxesColor, Bg: lc.Bg})
+		}
+	}
+
+	return buf
+}
+
+// Buffer implements Bufferer interface.
+func (lc *LineChart) Buffer() Buffer {
+	buf := lc.Block.Buffer()
+
+	if lc.Data == nil || len(lc.Data) == 0 {
+		return buf
+	}
+	lc.calcLayout()
+	buf.Merge(lc.plotAxes())
+
+	if lc.Mode == "dot" {
+		buf.Merge(lc.renderDot())
+	} else {
+		buf.Merge(lc.renderBraille())
+	}
+
+	return buf
+}