add kpod stats function

Signed-off-by: Ryan Cole <rcyoalne@gmail.com>

vendor/github.com/buger/goterm/plot.go

@@ -0,0 +1,328 @@
+package goterm
+
+import (
+	"fmt"
+	"math"
+	"strings"
+)
+
+const (
+	AXIS_LEFT = iota
+	AXIS_RIGHT
+)
+
+const (
+	DRAW_INDEPENDENT = 1 << iota
+	DRAW_RELATIVE
+)
+
+type DataTable struct {
+	columns []string
+
+	rows [][]float64
+}
+
+func (d *DataTable) AddColumn(name string) {
+	d.columns = append(d.columns, name)
+}
+
+func (d *DataTable) AddRow(elms ...float64) {
+	d.rows = append(d.rows, elms)
+}
+
+type Chart interface {
+	Draw(data DataTable, flags int) string
+}
+
+type LineChart struct {
+	Buf      []string
+	chartBuf []string
+
+	data *DataTable
+
+	Width  int
+	Height int
+
+	chartHeight int
+	chartWidth  int
+
+	paddingX int
+
+	paddingY int
+
+	Flags int
+}
+
+func genBuf(size int) []string {
+	buf := make([]string, size)
+
+	for i := 0; i < size; i++ {
+		buf[i] = " "
+	}
+
+	return buf
+}
+
+// Format float
+func ff(num interface{}) string {
+	return fmt.Sprintf("%.1f", num)
+}
+
+func NewLineChart(width, height int) *LineChart {
+	chart := new(LineChart)
+	chart.Width = width
+	chart.Height = height
+	chart.Buf = genBuf(width * height)
+
+	// axis lines + axies text
+	chart.paddingY = 2
+
+	return chart
+}
+
+func (c *LineChart) DrawAxes(maxX, minX, maxY, minY float64, index int) {
+	side := AXIS_LEFT
+
+	if c.Flags&DRAW_INDEPENDENT != 0 {
+		if index%2 == 0 {
+			side = AXIS_RIGHT
+		}
+
+		c.DrawLine(c.paddingX-1, 1, c.Width-c.paddingX, 1, "-")
+	} else {
+		c.DrawLine(c.paddingX-1, 1, c.Width-1, 1, "-")
+	}
+
+	if side == AXIS_LEFT {
+		c.DrawLine(c.paddingX-1, 1, c.paddingX-1, c.Height-1, "│")
+	} else {
+		c.DrawLine(c.Width-c.paddingX, 1, c.Width-c.paddingX, c.Height-1, "│")
+	}
+
+	left := 0
+	if side == AXIS_RIGHT {
+		left = c.Width - c.paddingX + 1
+	}
+
+	if c.Flags&DRAW_RELATIVE != 0 {
+		c.writeText(ff(minY), left, 1)
+	} else {
+		if minY > 0 {
+			c.writeText("0", left, 1)
+		} else {
+			c.writeText(ff(minY), left, 1)
+		}
+	}
+
+	c.writeText(ff(maxY), left, c.Height-1)
+
+	c.writeText(ff(minX), c.paddingX, 0)
+
+	x_col := c.data.columns[0]
+	c.writeText(c.data.columns[0], c.Width/2-len(x_col)/2, 1)
+
+	if c.Flags&DRAW_INDEPENDENT != 0 || len(c.data.columns) < 3 {
+		col := c.data.columns[index]
+
+		for idx, char := range strings.Split(col, "") {
+			start_from := c.Height/2 + len(col)/2 - idx
+
+			if side == AXIS_LEFT {
+				c.writeText(char, c.paddingX-1, start_from)
+			} else {
+				c.writeText(char, c.Width-c.paddingX, start_from)
+			}
+		}
+	}
+
+	if c.Flags&DRAW_INDEPENDENT != 0 {
+		c.writeText(ff(maxX), c.Width-c.paddingX-len(ff(maxX)), 0)
+	} else {
+		c.writeText(ff(maxX), c.Width-len(ff(maxX)), 0)
+	}
+}
+
+func (c *LineChart) writeText(text string, x, y int) {
+	coord := y*c.Width + x
+
+	for idx, char := range strings.Split(text, "") {
+		c.Buf[coord+idx] = char
+	}
+}
+
+func (c *LineChart) Draw(data *DataTable) (out string) {
+	var scaleY, scaleX float64
+
+	c.data = data
+
+	if c.Flags&DRAW_INDEPENDENT != 0 && len(data.columns) > 3 {
+		fmt.Println("Error: Can't use DRAW_INDEPENDENT for more then 2 graphs")
+		return ""
+	}
+
+	charts := len(data.columns) - 1
+
+	prevPoint := [2]int{-1, -1}
+
+	maxX, minX, maxY, minY := getBoundaryValues(data, -1)
+
+	c.paddingX = int(math.Max(float64(len(ff(minY))), float64(len(ff(maxY))))) + 1
+
+	c.chartHeight = c.Height - c.paddingY
+
+	if c.Flags&DRAW_INDEPENDENT != 0 {
+		c.chartWidth = c.Width - 2*c.paddingX
+	} else {
+		c.chartWidth = c.Width - c.paddingX - 1
+	}
+
+	scaleX = float64(c.chartWidth) / (maxX - minX)
+
+	if c.Flags&DRAW_RELATIVE != 0 || minY < 0 {
+		scaleY = float64(c.chartHeight) / (maxY - minY)
+	} else {
+		scaleY = float64(c.chartHeight) / maxY
+	}
+
+	for i := 1; i < charts+1; i++ {
+		if c.Flags&DRAW_INDEPENDENT != 0 {
+			maxX, minX, maxY, minY = getBoundaryValues(data, i)
+
+			scaleX = float64(c.chartWidth-1) / (maxX - minX)
+			scaleY = float64(c.chartHeight) / maxY
+
+			if c.Flags&DRAW_RELATIVE != 0 || minY < 0 {
+				scaleY = float64(c.chartHeight) / (maxY - minY)
+			}
+		}
+
+		symbol := Color("•", i)
+
+		c_data := getChartData(data, i)
+
+		for _, point := range c_data {
+			x := int((point[0]-minX)*scaleX) + c.paddingX
+			y := int((point[1])*scaleY) + c.paddingY
+
+			if c.Flags&DRAW_RELATIVE != 0 || minY < 0 {
+				y = int((point[1]-minY)*scaleY) + c.paddingY
+			}
+
+			if prevPoint[0] == -1 {
+				prevPoint[0] = x
+				prevPoint[1] = y
+			}
+
+			if prevPoint[0] <= x {
+				c.DrawLine(prevPoint[0], prevPoint[1], x, y, symbol)
+			}
+
+			prevPoint[0] = x
+			prevPoint[1] = y
+		}
+
+		c.DrawAxes(maxX, minX, maxY, minY, i)
+	}
+
+	for row := c.Height - 1; row >= 0; row-- {
+		out += strings.Join(c.Buf[row*c.Width:(row+1)*c.Width], "") + "\n"
+	}
+
+	return
+}
+
+func (c *LineChart) DrawLine(x0, y0, x1, y1 int, symbol string) {
+	drawLine(x0, y0, x1, y1, func(x, y int) {
+		coord := y*c.Width + x
+
+		if coord > 0 && coord < len(c.Buf) {
+			c.Buf[coord] = symbol
+		}
+	})
+}
+
+func getBoundaryValues(data *DataTable, index int) (maxX, minX, maxY, minY float64) {
+	maxX = data.rows[0][0]
+	minX = data.rows[0][0]
+	maxY = data.rows[0][1]
+	minY = data.rows[0][1]
+
+	for _, r := range data.rows {
+		maxX = math.Max(maxX, r[0])
+		minX = math.Min(minX, r[0])
+
+		for idx, c := range r {
+			if idx > 0 {
+				if index == -1 || index == idx {
+					maxY = math.Max(maxY, c)
+					minY = math.Min(minY, c)
+				}
+			}
+		}
+	}
+
+	if maxY > 0 {
+		maxY = maxY * 1.1
+	} else {
+		maxY = maxY * 0.9
+	}
+
+	if minY > 0 {
+		minY = minY * 0.9
+	} else {
+		minY = minY * 1.1
+	}
+
+	return
+}
+
+// DataTable can contain data for multiple graphs, we need to extract only 1
+func getChartData(data *DataTable, index int) (out [][]float64) {
+	for _, r := range data.rows {
+		out = append(out, []float64{r[0], r[index]})
+	}
+
+	return
+}
+
+// Algorithm for drawing line between two points
+//
+// http://en.wikipedia.org/wiki/Bresenham's_line_algorithm
+func drawLine(x0, y0, x1, y1 int, plot func(int, int)) {
+	dx := x1 - x0
+	if dx < 0 {
+		dx = -dx
+	}
+	dy := y1 - y0
+	if dy < 0 {
+		dy = -dy
+	}
+	var sx, sy int
+	if x0 < x1 {
+		sx = 1
+	} else {
+		sx = -1
+	}
+	if y0 < y1 {
+		sy = 1
+	} else {
+		sy = -1
+	}
+	err := dx - dy
+
+	for {
+		plot(x0, y0)
+		if x0 == x1 && y0 == y1 {
+			break
+		}
+		e2 := 2 * err
+		if e2 > -dy {
+			err -= dy
+			x0 += sx
+		}
+		if e2 < dx {
+			err += dx
+			y0 += sy
+		}
+	}
+}