Grayscale image

config/config.go

@@ -18,6 +18,10 @@ type config struct {
 	Password  string `json:"password"`
 	Server    string `json:"server"`
 	Port      int    `json:"port"`
+	Color bool
+	Compress bool
+	NoImage bool
+	ImageDir string
 }
 const DefaultTimeout = 120
 const XdgConfigHome = "XDG_CONFIG_HOME"

epubgen/epub.go

@@ -2,6 +2,8 @@ package epubgen
 
 import (
 	"errors"
+	"github.com/nikhil1raghav/kindle-send/imageutil"
+	"log"
 	"os"
 	"path"
 	"sync"
@@ -18,7 +20,18 @@ type epubmaker struct {
 	Epub      *epub.Epub
 	downloads map[string]string
 }
-
+func createTempImageDir() (string, error){
+	storePath:=config.GetInstance().StorePath
+	if len(storePath)==0{
+		curDir , err := os.Getwd()
+		if err!=nil{
+			storePath="./"
+		}else{
+			storePath=curDir
+		}
+	}
+	return os.MkdirTemp(storePath, "img")
+}
 func NewEpubmaker(title string) *epubmaker {
 	downloadMap := make(map[string]string)
 	return &epubmaker{
@@ -30,7 +43,10 @@ func NewEpubmaker(title string) *epubmaker {
 func fetchReadable(url string) (readability.Article, error) {
 	return readability.FromURL(url, 30*time.Second)
 }
-
+//remove images from the document
+func (e *epubmaker) removeImages(i int, img *goquery.Selection){
+	img.Remove()
+}
 //Point remote image link to downloaded image
 func (e *epubmaker) changeRefs(i int, img *goquery.Selection) {
 	img.RemoveAttr("loading")
@@ -58,9 +74,15 @@ func (e *epubmaker) downloadImages(i int, img *goquery.Selection) {
 
 		//pass unique and safe image names here, then it will not crash on windows
 		//use murmur hash to generate file name
-		imageFileName:=util.GetHash(imgSrc)
+		log.Println("Queuing for download ",imgSrc)
+		imageFileName, err:=imageutil.Process(imgSrc)
+		log.Println("ImageFIlename", imageFileName)
+		if err!=nil{
+			util.Red.Printf("Error processing image %s : %s\n", imgSrc, err)
+			return
+		}
 
-		imgRef, err := e.Epub.AddImage(imgSrc, imageFileName)
+		imgRef, err := e.Epub.AddImage(imageFileName,"")
 		if err != nil {
 			util.Red.Printf("Couldn't add image %s : %s\n", imgSrc, err)
 			return
@@ -77,6 +99,12 @@ func (e *epubmaker) embedImages(wg *sync.WaitGroup, article *readability.Article
 	defer wg.Done()
 	//TODO: Compress images before embedding to improve size
 	doc := goquery.NewDocumentFromNode(article.Node)
+	cfg:=config.GetInstance()
+	if cfg.NoImage{
+		doc.Find("img").Each(e.removeImages)
+		return
+	}
+
 
 	//download all images
 	doc.Find("img").Each(e.downloadImages)
@@ -120,6 +148,19 @@ func (e *epubmaker) addContent(articles *[]readability.Article) error {
 func Make(pageUrls []string, title string) (string, error) {
 	//TODO: Parallelize fetching pages
 
+	cfg:=config.GetInstance()
+	//create directory to store images
+	if !cfg.NoImage{
+
+		imgdir, err:=createTempImageDir()
+		if err!=nil{
+			util.Red.Println("Couldn't create directory to store images, saving document without images")
+			cfg.NoImage=true
+		}else{
+			cfg.ImageDir=imgdir
+			defer os.RemoveAll(imgdir)
+		}
+	}
 	//Get readable article from urls
 	readableArticles := make([]readability.Article, 0)
 	for _, pageUrl := range pageUrls {
@@ -175,5 +216,10 @@ func Make(pageUrls []string, title string) (string, error) {
 	if err != nil {
 		return "", err
 	}
+	if !cfg.NoImage{
+		if len(cfg.ImageDir)!=0{
+			//os.RemoveAll(cfg.ImageDir)
+		}
+	}
 	return filename, nil
 }

imageutil/image.go

@@ -0,0 +1,46 @@
+package imageutil
+
+import (
+	"image"
+	"image/png"
+	"log"
+	"os"
+)
+func WriteToGray(filePath string){
+	img, err:= loadImage(filePath)
+	if err!=nil{
+		log.Println(err)
+		return
+	}
+
+	grayImage := rgbaToGray(img)
+	os.Remove(filePath)
+	f,_:=os.Create(filePath)
+	defer f.Close()
+	png.Encode(f,grayImage)
+}
+func loadImage(filePath string)(image.Image, error){
+	infile, err:=os.Open(filePath)
+	if err!=nil{
+		return nil, err
+	}
+	defer infile.Close()
+	img, _ , err:=image.Decode(infile)
+	if err!=nil{
+		return nil, err
+	}
+	return img, nil
+}
+func rgbaToGray(img image.Image) *image.Gray{
+	var(
+		bounds = img.Bounds()
+		gray = image.NewGray(bounds)
+	)
+	for x:=0;x<bounds.Max.X;x++{
+		for y:=0;y<bounds.Max.Y;y++{
+			var rgba = img.At(x,y)
+			gray.Set(x, y, rgba)
+		}
+	}
+	return gray
+}

imageutil/process.go

@@ -0,0 +1,57 @@
+package imageutil
+
+import (
+	"errors"
+	"fmt"
+	"github.com/nikhil1raghav/kindle-send/config"
+	"github.com/nikhil1raghav/kindle-send/util"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"path"
+)
+
+//Process the image and send the filename to add in epub
+func Process(imageUrl string)(string, error){
+	cfg:=config.GetInstance()
+	downloaded, err :=download(imageUrl)
+	if err!=nil{
+		return "", err
+	}
+	if cfg.Color{
+		fmt.Println("Value of color is true")
+	}
+	if !cfg.Color{
+		WriteToGray(downloaded)
+	}
+	return downloaded, nil
+}
+
+func download(imageUrl string)(string, error){
+
+	response, err:=http.Get(imageUrl)
+	if err!=nil{
+		return "",err
+	}
+	defer response.Body.Close()
+	if response.StatusCode!=200{
+		log.Println("Got non 200 response")
+		return "", errors.New("Non 200 response")
+	}
+
+	log.Println("Got response for ", imageUrl)
+
+	file, err:=os.Create(path.Join(config.GetInstance().ImageDir, util.GetHash(imageUrl)))
+	log.Println("Writing to file ", file.Name())
+	if err!=nil{
+		return "", err
+	}
+	defer file.Close()
+	_, err = io.Copy(file, response.Body)
+	if err!=nil{
+		return "", err
+	}
+	log.Println("Written successfully to ", file.Name())
+	return file.Name(), nil
+}

main.go

@@ -49,6 +49,8 @@ func main() {
 	mailTimeout :=flag.Int("mail-timeout",120, "Timeout for sending mail in Seconds" )
 	_ =flag.Bool("version", false, "Print version information")
 	_ =flag.Bool("dry-run", false, "Save epub locally and don't send to device")
+	_=flag.Bool("no-image", false, "Render epub without images")
+	_=flag.Bool("color", false, "By default epub is rendered with grayscale image to reduce size,\npass --color to render with colored image")
 
 	flag.Parse()
 	passed := 0
@@ -83,6 +85,13 @@ func main() {
 		util.Red.Println(err)
 		return
 	}
+	cfg:=config.GetInstance()
+	if flagPassed("no-image"){
+		cfg.NoImage=true
+	}
+	if flagPassed("color"){
+		cfg.Color=true
+	}
 	filesToSend := make([]string, 0)
 	if len(*filePath) != 0 {
 		filesToSend = append(filesToSend, *filePath)
@@ -96,6 +105,7 @@ func main() {
 		}
 	}
 
+
 	if flagPassed("dry-run"){
 		util.CyanBold.Println("Dry-run mode : Not sending files to device")
 		util.Cyan.Println("Following files are saved")