Merge pull request #15 from CIAvash/chroma_styles

Add style and list-styles options

.gitignore

@@ -1,2 +1,3 @@
 .DS_Store
 germanium
+!germanium/

README.md

@@ -20,9 +20,12 @@ FLAGS:
     -b, --background <COLOR>  Background color of the image [default: #aaaaff]
     -f, --font <FONT>         Specify font eg. 'Hack-Bold'
     -l, --language <LANG>     The language for syntax highlighting eg. 'go'
+    -s, --style <STYLE>       The style for syntax highlighting eg. 'dracula'
+    --list-styles             List all available styles for syntax highlighting
     --list-fonts              List all available fonts in your system
     --no-line-number          Hide the line number
     --no-window-access-bar    Hide the window access bar
+    -v, --version             Show Version
 ```
 
 ### Example
@@ -39,6 +42,12 @@ Generate image From Stdin (need to add option `-l` or `--language`)
 cat main.go | germanium -l go -o main.png -
 ```
 
+Generate image with another style (you can get a list of them with `--list-styles`)
+
+```
+germanium -s solarized-dark -o main.png main.go
+```
+
 Generate image without line number
 
 ```

TODO

@@ -1,7 +1,7 @@
 - [] upgrade accuracy about drawing circle
 - [] shadow blur
 - [] padding between line
-- [] chroma theme
+- [x] chroma theme
 - [] clipboard
-- [] language
+- [x] language
 - [] background image

cli/cli.go

@@ -7,6 +7,7 @@ import (
 	"path/filepath"
 
 	flags "github.com/jessevdk/go-flags"
+	"github.com/alecthomas/chroma/styles"
 	"github.com/matsuyoshi30/germanium"
 )
 
@@ -46,6 +47,13 @@ func Run() (err error) {
 		filename = args[0]
 	}
 
+	if opts.ListStyles {
+		for _, name := range styles.Names() {
+			fmt.Printf("%s ", name)
+		}
+		return nil
+	}
+
 	if opts.ListFonts {
 		germanium.ListFonts()
 		return nil
@@ -99,11 +107,16 @@ func run(r io.Reader, filename string) error {
 		return err
 	}
 
+	// set default style to dracula
+	style := `dracula`
+	if opts.Style != `` {
+		style = opts.Style
+	}
 	image := germanium.NewImage(src, face, opts.NoWindowAccessBar)
-	if err := image.Draw(opts.BackgroundColor, opts.NoWindowAccessBar); err != nil {
+	if err := image.Draw(opts.BackgroundColor, style, opts.NoWindowAccessBar); err != nil {
 		return err
 	}
-	if err := image.Label(out, filename, src, opts.Language, face, !opts.NoLineNum); err != nil {
+	if err := image.Label(out, filename, src, opts.Language, style, face, !opts.NoLineNum); err != nil {
 		return err
 	}
 

cli/options.go

@@ -5,6 +5,8 @@ type Options struct {
 	BackgroundColor   string `short:"b" long:"background" default:"#aaaaff" description:"Background color of the image"`
 	Font              string `short:"f" long:"font" default:"Hack-Regular" description:"Specify font eg. 'Hack-Bold'"`
 	Language          string `short:"l" long:"language" description:"The language for syntax highlighting"`
+	Style             string `short:"s" long:"style" description:"The style for syntax highlighting"`
+	ListStyles        bool   `long:"list-styles" description:"List all available styles for syntax highlighting"`
 	ListFonts         bool   `long:"list-fonts" description:"List all available fonts in your system"`
 	NoLineNum         bool   `long:"no-line-number" description:"Hide the line number"`
 	NoWindowAccessBar bool   `long:"no-window-access-bar" description:"Hide the window access bar"`

cli/usage.go

@@ -8,6 +8,8 @@ FLAGS:
     -b, --background <COLOR>  Background color of the image [default: #aaaaff]
     -f, --font <FONT>         Specify font eg. 'Hack-Bold'
     -l, --language <LANG>     The language for syntax highlighting eg. 'go'
+    -s, --style <STYLE>       The style for syntax highlighting eg. 'dracula'
+    --list-styles             List all available styles for syntax highlighting
     --list-fonts              List all available fonts in your system
     --no-line-number          Hide the line number
     --no-window-access-bar    Hide the window access bar

cmd/germanium/testdata/broken-style.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+# Test a style that has no background color or missing colors for some tokens
+../../../germanium -s pygments main.go -o broken-style-gen.png

cmd/germanium/testdata/light-style.sh

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+# Test a style that has a light background color, and missing colors for some tokens
+# The line numbers should be black
+../../../germanium -s autumn main.go -o light-style-gen.png

cmd/germanium/testdata/style.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+../../../germanium -s solarized-dark main.go -o style-gen.png

formatter.go

@@ -53,7 +53,7 @@ func (f *PNGFormatter) format(w io.Writer, style *chroma.Style, tokens []chroma.
 		if f.hasLineNum {
 			f.drawer.Dot.X = left
 			f.drawer.Dot.Y = y
-			f.drawer.Src = image.NewUniform(color.White)
+			f.drawer.Src = image.NewUniform(chooseColorBasedOnContrast())
 			f.drawer.DrawString(fmt.Sprintf(format, i+1))
 		}
 
@@ -64,8 +64,26 @@ func (f *PNGFormatter) format(w io.Writer, style *chroma.Style, tokens []chroma.
 
 		f.drawer.Dot.X = sx
 		for _, t := range tokens {
-			s := style.Get(t.Type)
-			f.drawer.Src = image.NewUniform(color.RGBA{s.Colour.Red(), s.Colour.Green(), s.Colour.Blue(), 255})
+			var tokenColor color.Color
+			chromaTokenColor := style.Get(t.Type).Colour
+			if chromaTokenColor == 0 {
+				// if token has no color, try to use the color of the Text token
+				chromaTokenColor = style.Get(chroma.Text).Colour
+			}
+			if chromaTokenColor != 0 {
+				tokenColor = color.RGBA{
+					chromaTokenColor.Red(),
+					chromaTokenColor.Green(),
+					chromaTokenColor.Blue(),
+					255,
+				}
+			} else {
+				// found no suitable color for token, so use white if background color is close
+				// to black and use black if background color is close to white
+				tokenColor = chooseColorBasedOnContrast()
+			}
+
+			f.drawer.Src = image.NewUniform(tokenColor)
 
 			for _, c := range t.String() {
 				if c == '\n' {
@@ -88,3 +106,15 @@ func (f *PNGFormatter) format(w io.Writer, style *chroma.Style, tokens []chroma.
 
 	return png.Encode(w, f.drawer.Dst)
 }
+
+// Choose white or black color based on window background color
+func chooseColorBasedOnContrast() color.Color {
+	black := color.Black
+	white := color.White
+	colorIndex := color.Palette{black, white}.Index(windowBackgroundColor)
+	if colorIndex == 0 {
+		return white
+	} else {
+		return black
+	}
+}

panel.go

@@ -22,8 +22,8 @@ var (
 
 	radius = 10
 
-	// image color
-	dracula = color.RGBA{40, 42, 54, 255}
+	// default window background color
+	windowBackgroundColor = color.RGBA{40, 42, 54, 255}
 
 	// button color
 	close   = color.RGBA{255, 95, 86, 255}
@@ -72,7 +72,7 @@ func NewPanel(sx, sy, ex, ey int) *Panel {
 	return &Panel{img: image.NewRGBA(image.Rect(sx, sy, ex, ey))}
 }
 
-func (base *Panel) Draw(backgroundColor string, noWindowAccessBar bool) error {
+func (base *Panel) Draw(backgroundColor string, style string, noWindowAccessBar bool) error {
 	bg, err := ParseHexColor(backgroundColor)
 	if err != nil {
 		return err
@@ -84,6 +84,18 @@ func (base *Panel) Draw(backgroundColor string, noWindowAccessBar bool) error {
 	// base image
 	base.fillColor(bg)
 
+	// use the background color of the Chroma style, if it exists
+	chromaStyle := styles.Get(style)
+	chromaBackgroundColor := chromaStyle.Get(chroma.Background).Background
+	if chromaBackgroundColor != 0 {
+		windowBackgroundColor = color.RGBA{
+			R: chromaBackgroundColor.Red(),
+			G: chromaBackgroundColor.Green(),
+			B: chromaBackgroundColor.Blue(),
+			A: 255,
+		}
+	}
+
 	base.drawWindowPanel(width, height)
 
 	// window control bar
@@ -101,13 +113,13 @@ func (base *Panel) Draw(backgroundColor string, noWindowAccessBar bool) error {
 
 func (p *Panel) drawWindowPanel(w, h int) {
 	window := NewPanel(paddingWidth, paddingHeight, w-paddingWidth, h-paddingHeight)
-	window.fillColor(dracula)
+	window.fillColor(windowBackgroundColor)
 	draw.Draw(p.img, p.img.Bounds(), window.img, image.Point{0, 0}, draw.Over)
 }
 
 func (p *Panel) drawWindowControlPanel(w, h int) {
 	wc := NewPanel(paddingWidth, paddingHeight, w-paddingWidth, paddingHeight+windowHeight)
-	wc.fillColor(dracula)
+	wc.fillColor(windowBackgroundColor)
 
 	wc.drawControlButtons()
 
@@ -135,7 +147,7 @@ func (p *Panel) drawRound(w, h int) {
 		image.Point{w - paddingWidth, h - paddingHeight},
 	}
 	for _, c := range corners {
-		round.drawCircle(c, radius, dracula)
+		round.drawCircle(c, radius, windowBackgroundColor)
 	}
 	draw.Draw(p.img, p.img.Bounds(), round.img, image.Point{0, 0}, draw.Over)
 }
@@ -148,7 +160,7 @@ func (p *Panel) drawAroundBar(w, h int) {
 		NewPanel(paddingWidth, h-paddingHeight, w-paddingWidth, h-paddingHeight+radius),
 	}
 	for _, ab := range aroundbars {
-		ab.fillColor(dracula)
+		ab.fillColor(windowBackgroundColor)
 		draw.Draw(p.img, p.img.Bounds(), ab.img, image.Point{0, 0}, draw.Over)
 	}
 }
@@ -205,7 +217,7 @@ func (p *Panel) drawCircle(center image.Point, radius int, c color.RGBA) {
 }
 
 // Label labels highlighted source code on panel
-func (p *Panel) Label(out io.Writer, filename, src, language string, face font.Face, hasLineNum bool) error {
+func (p *Panel) Label(out io.Writer, filename, src, language string, style string, face font.Face, hasLineNum bool) error {
 	var lexer chroma.Lexer
 	if language != "" {
 		lexer = lexers.Get(language)
@@ -217,10 +229,7 @@ func (p *Panel) Label(out io.Writer, filename, src, language string, face font.F
 	}
 	lexer = chroma.Coalesce(lexer)
 
-	style := styles.Get("dracula")
-	if style == nil {
-		style = styles.Fallback
-	}
+	chromaStyle := styles.Get(style)
 
 	iterator, err := lexer.Tokenise(nil, src)
 	if err != nil {
@@ -241,7 +250,7 @@ func (p *Panel) Label(out io.Writer, filename, src, language string, face font.F
 		formatter = formatters.Fallback
 	}
 
-	if err := p.Formatter.Format(out, style, iterator); err != nil {
+	if err := p.Formatter.Format(out, chromaStyle, iterator); err != nil {
 		return err
 	}