Added line number mode. (#8)

* Added line number mode.

The command line option is "-n" for line number mode.
The keyboard shortcut key is "G".

Change the specifications to apply the background color alternately.
Add a background color from the beginning to the end of the screen.
It also adds a background color to blank lines.

README.md

@@ -1,4 +1,4 @@
-# OV - Oviewer
+# ov - Oviewer
 
 [![Actions Status](https://github.com/noborus/ov/workflows/Go/badge.svg)](https://github.com/noborus/ov/actions)
 [![Go Report Card](https://goreportcard.com/badge/github.com/noborus/ov)](https://goreportcard.com/report/github.com/noborus/ov)
@@ -137,6 +137,8 @@ Flags:
 
 ![header](https://raw.githubusercontent.com/noborus/ov/master/docs/ov-header.gif)
 
+### line number (<kbd>G</kbd>)
+
 ### psql
 
 Set environment variable `PSQL_PAGER`(PostgreSQL 11 or later).
@@ -193,6 +195,7 @@ pager=ov -w=f -H3 -F -C -d "|"
 * <kbd>w</kbd> - wrap/nowrap toggle
 * <kbd>c</kbd> - column mode enable/disable toggle
 * <kbd>C</kbd> - color to alternate rows enable/disable toggle
+* <kbd>G</kbd> - line number toogle
 
 ### Input Mode
 

go.mod

@@ -18,11 +18,10 @@ require (
 	github.com/spf13/cobra v1.0.0
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
-	github.com/spf13/viper v1.6.3
+	github.com/spf13/viper v1.7.0
 	github.com/stretchr/testify v1.5.1 // indirect
 	github.com/ulikunitz/xz v0.5.7
 	golang.org/x/crypto v0.0.0-20200429183012-4b2356b1ed79
-	golang.org/x/sys v0.0.0-20200501145240-bc7a7d42d5c3 // indirect
-	golang.org/x/text v0.3.2 // indirect
-	gopkg.in/ini.v1 v1.55.0 // indirect
+	golang.org/x/sys v0.0.0-20200509044756-6aff5f38e54f // indirect
+	gopkg.in/ini.v1 v1.56.0 // indirect
 )

internal/oviewer/draw.go

@@ -17,17 +17,7 @@ func (root *Root) Draw() {
 		return
 	}
 
-	space := Content{
-		mainc: ' ',
-		combc: nil,
-		width: 1,
-		style: tcell.StyleDefault.Normal(),
-	}
-	for y := 0; y < m.vHight; y++ {
-		for x := 0; x < m.vWidth; x++ {
-			screen.SetContent(x, y, space.mainc, space.combc, space.style)
-		}
-	}
+	root.ResetScreen()
 
 	bottom := root.bottomLineNum(m.BufEndNum()) - root.Header
 	if m.lineNum > bottom+1 {
@@ -43,11 +33,10 @@ func (root *Root) Draw() {
 		searchWord = root.input
 	}
 
-	// Header
 	lY := 0
 	lX := 0
-	hy := 0
-	for lY < root.Header {
+	// Header
+	for hy := 0; lY < root.Header; hy++ {
 		line := m.GetLine(lY)
 		lc, err := m.lineToContents(lY, root.TabWidth)
 		if err != nil {
@@ -68,7 +57,6 @@ func (root *Root) Draw() {
 		} else {
 			lX, lY = root.noWrapContents(hy, m.x, lY, contents)
 		}
-		hy++
 	}
 
 	// Body
@@ -77,26 +65,16 @@ func (root *Root) Draw() {
 		lc, err := m.lineToContents(m.lineNum+lY, root.TabWidth)
 		if err != nil {
 			// EOF
-			root.Screen.SetContent(0, y, '~', nil, tcell.StyleDefault.Foreground(tcell.ColorGray))
+			screen.SetContent(0, y, '~', nil, tcell.StyleDefault.Foreground(tcell.ColorGray))
 			continue
 		}
 
 		line := m.GetLine(m.lineNum + lY)
 
-		// alternate background color
-		if root.AlternateRows {
-			bgColor := normalBgColor
-			if (root.Model.lineNum+lY)%2 == 1 {
-				bgColor = root.ColorAlternate
-			}
-			for n := range lc.contents {
-				lc.contents[n].style = lc.contents[n].style.Background(bgColor)
-			}
-		}
-
 		for n := range lc.contents {
 			lc.contents[n].style = lc.contents[n].style.Reverse(false)
 		}
+
 		// search highlight
 		if searchWord != "" {
 			poss := searchPosition(line, searchWord, root.CaseSensitive)
@@ -111,11 +89,31 @@ func (root *Root) Draw() {
 			reverseContents(lc, r)
 		}
 
+		// line number mode
+		if root.LineNumMode {
+			lineNum := strToContents(fmt.Sprintf("%*d", root.startPos-1, root.Model.lineNum+lY-root.Header+1), root.TabWidth)
+			root.setContentString(0, y, lineNum, tcell.StyleDefault.Bold(true))
+		}
+
+		var nextY int
 		if root.WrapMode {
-			lX, lY = root.wrapContents(y, lX, lY, lc.contents)
+			lX, nextY = root.wrapContents(y, lX, lY, lc.contents)
 		} else {
-			lX, lY = root.noWrapContents(y, m.x, lY, lc.contents)
+			lX, nextY = root.noWrapContents(y, m.x, lY, lc.contents)
 		}
+
+		// alternate background color
+		if root.AlternateRows {
+			bgColor := normalBgColor
+			if (m.lineNum+lY)%2 == 1 {
+				bgColor = root.ColorAlternate
+			}
+			for x := 0; x < m.vWidth; x++ {
+				r, c, style, _ := root.GetContent(x, y)
+				root.SetContent(x, y, r, c, style.Background(bgColor))
+			}
+		}
+		lY = nextY
 	}
 
 	if lY > 0 {
@@ -128,51 +126,62 @@ func (root *Root) Draw() {
 	root.Show()
 }
 
+// ResetScreen initializes the screen with a blank
+func (root *Root) ResetScreen() {
+	space := Content{
+		mainc: ' ',
+		combc: nil,
+		width: 1,
+		style: tcell.StyleDefault.Normal(),
+	}
+	for y := 0; y < root.Model.vHight; y++ {
+		for x := 0; x < root.Model.vWidth; x++ {
+			root.Screen.SetContent(x, y, space.mainc, space.combc, space.style)
+		}
+	}
+}
+
 // reverses the specified range.
 func reverseContents(lc lineContents, r rangePos) {
 	for n := lc.cMap[r.start]; n < lc.cMap[r.end]; n++ {
 		lc.contents[n].style = lc.contents[n].style.Reverse(true)
 	}
 }
 
-// wrapContents returns the wrapped content.
-func (root *Root) wrapContents(y int, lX int, lY int, contents []Content) (rX int, rY int) {
-	wX := 0
-	for {
-		if lX+wX >= len(contents) {
+// wrapContents wraps and draws the contents and returns the next drawing position.
+func (root *Root) wrapContents(y int, lX int, lY int, contents []Content) (int, int) {
+	for x := 0; ; x++ {
+		if lX+x >= len(contents) {
 			// EOL
 			lX = 0
 			lY++
 			break
 		}
-		content := contents[lX+wX]
-		if wX+content.width > root.Model.vWidth {
+		content := contents[lX+x]
+		if x+content.width+root.startPos > root.Model.vWidth {
 			// next line
-			lX += wX
+			lX += x
 			break
 		}
-		style := content.style
-		root.Screen.SetContent(wX, y, content.mainc, content.combc, style)
-		wX++
+		root.Screen.SetContent(x+root.startPos, y, content.mainc, content.combc, content.style)
 	}
 	return lX, lY
 }
 
-// returns unwrapped contents.
-func (root *Root) noWrapContents(y int, lX int, lY int, contents []Content) (rX int, rY int) {
+// noWrapContents draws contents without wrapping and returns the next drawing position.
+func (root *Root) noWrapContents(y int, lX int, lY int, contents []Content) (int, int) {
 	if lX < root.minStartPos {
 		lX = root.minStartPos
 	}
-	for x := 0; x < root.Model.vWidth; x++ {
+	for x := 0; x+root.startPos < root.Model.vWidth; x++ {
 		if lX+x < 0 {
 			continue
 		}
 		if lX+x >= len(contents) {
 			break
 		}
 		content := contents[lX+x]
-		style := content.style
-		root.Screen.SetContent(x, y, content.mainc, content.combc, style)
+		root.Screen.SetContent(x+root.startPos, y, content.mainc, content.combc, content.style)
 	}
 	lY++
 	return lX, lY

internal/oviewer/keybind.go

@@ -128,6 +128,8 @@ func (root *Root) defaultEvent(ev *tcell.EventKey) bool {
 			root.input = ""
 			root.setMode(goline)
 			return true
+		case 'G':
+			root.toggleLineNumMode()
 		case 'H':
 			root.input = ""
 			root.setMode(header)

internal/oviewer/model.go

@@ -97,9 +97,9 @@ func (m *Model) GetContents(lineNum int, tabWidth int) []Content {
 // NewCache creates a new cache.
 func (m *Model) NewCache() error {
 	cache, err := ristretto.NewCache(&ristretto.Config{
-		NumCounters: 1e7,     // number of keys to track frequency of (10M).
-		MaxCost:     1 << 30, // maximum cost of cache (1GB).
-		BufferItems: 64,      // number of keys per Get buffer.
+		NumCounters: 10000, // number of keys to track frequency of (10M).
+		MaxCost:     1000,  // maximum cost of cache (1GB).
+		BufferItems: 64,    // number of keys per Get buffer.
 	})
 	if err != nil {
 		return err

internal/oviewer/oviewer.go

@@ -25,9 +25,11 @@ type Root struct {
 	AlternateRows   bool
 	ColumnMode      bool
 	ColumnDelimiter string
+	LineNumMode     bool
 
 	Model         *Model
 	wrapHeaderLen int
+	startPos      int
 	bottomPos     int
 	statusPos     int
 	fileName      string
@@ -69,6 +71,7 @@ func New() *Root {
 	root.ColorAlternate = tcell.ColorGray
 	root.ColumnDelimiter = ""
 	root.columnNum = 0
+	root.startPos = 0
 	return root
 }
 
@@ -141,6 +144,15 @@ func (root *Root) toggleAlternateRows() {
 	}
 }
 
+func (root *Root) toggleLineNumMode() {
+	if root.LineNumMode {
+		root.LineNumMode = false
+	} else {
+		root.LineNumMode = true
+	}
+	root.updateEndNum()
+}
+
 func (root *Root) setMode(mode Mode) {
 	root.mode = mode
 }
@@ -203,6 +215,7 @@ func (root *Root) Resize() {
 
 // Sync redraws the whole thing.
 func (root *Root) Sync() {
+	root.PreparelineNum()
 	root.PrepareView()
 	root.Draw()
 }
@@ -220,6 +233,18 @@ loop:
 	timer.Stop()
 }
 
+func (root *Root) PreparelineNum() {
+	root.startPos = 0
+	if root.LineNumMode {
+		root.startPos = len(fmt.Sprintf("%d", root.Model.BufEndNum())) + 1
+	}
+}
+
+func (root *Root) updateEndNum() {
+	root.PreparelineNum()
+	root.statusDraw()
+}
+
 // main is manages and executes events in the main routine.
 func (root *Root) main() {
 	screen := root.Screen
@@ -230,7 +255,7 @@ loop:
 		ev := screen.PollEvent()
 		switch ev := ev.(type) {
 		case *eventTimer:
-			root.statusDraw()
+			root.updateEndNum()
 		case *eventAppQuit:
 			break loop
 		case *tcell.EventKey:

main.go

@@ -13,7 +13,7 @@ import (
 
 var (
 	// Version represents the version
-	Version string = "v0.1.1"
+	Version string = "dev"
 	// Revision set "git rev-parse --short HEAD"
 	Revision string = "HEAD"
 )
@@ -43,6 +43,8 @@ type Config struct {
 	ColumnMode bool
 	// Column Delimiter
 	ColumnDelimiter string
+	// Line Number
+	LineNumMode bool
 	// Debug is enable debug display.
 	Debug bool
 
@@ -83,6 +85,7 @@ It supports various compressed files(gzip, bzip2, zstd, lz4, and xz).
 		root.CaseSensitive = config.CaseSensitive
 		root.AlternateRows = config.AlternateRows
 		root.ColumnMode = config.ColumnMode
+		root.LineNumMode = config.LineNumMode
 		root.ColumnDelimiter = strings.ReplaceAll(config.ColumnDelimiter, "\\t", "\t")
 		if config.ColorAlternate != "" {
 			color := tcell.GetColor(config.ColorAlternate)
@@ -132,6 +135,9 @@ func init() {
 	rootCmd.PersistentFlags().StringVarP(&config.ColumnDelimiter, "column-delimiter", "d", ",", "column delimiter")
 	_ = viper.BindPFlag("ColumnDelimiter", rootCmd.PersistentFlags().Lookup("column-delimiter"))
 
+	rootCmd.PersistentFlags().BoolVarP(&config.LineNumMode, "line-number", "n", false, "line number")
+	_ = viper.BindPFlag("LineNumMode", rootCmd.PersistentFlags().Lookup("line-number"))
+
 	rootCmd.PersistentFlags().BoolVarP(&config.Debug, "debug", "", false, "debug mode")
 }