Add http server

cmd/convert.go

@@ -5,27 +5,19 @@ Copyright © 2022 NAME HERE <EMAIL ADDRESS>
 package cmd
 
 import (
-	"image"
-	"image/color"
-	_ "image/gif"
-	_ "image/jpeg"
-	_ "image/png"
 	"io"
 	"log"
 	"os"
 
+	"github.com/saunaclub/inkpot-cli/epd"
 	"github.com/spf13/cobra"
-	"golang.org/x/image/draw"
 )
 
 var width int
 var height int
+var infile string
 var outfile string
 
-func Foobar () (io.Writer, error) {
-	return os.Stdout, nil
-}
-
 // convertCmd represents the convert command
 var convertCmd = &cobra.Command{
 	Use:   "convert <file|->",
@@ -50,9 +42,9 @@ Pass "-" as the filename to read from stdin.`,
 			defer input.Close()
 		}
 
-	    // write to given outfile, default to stdout
-	    var output io.Writer
-		if outfile == "" {
+		// write to given outfile, default to stdout
+		var output io.Writer
+		if outfile == "" || outfile == "-" {
 			output = os.Stdout
 		} else {
 			file, err := os.OpenFile(outfile, os.O_RDWR|os.O_CREATE, 0644)
@@ -63,7 +55,7 @@ Pass "-" as the filename to read from stdin.`,
 			output = file
 		}
 
-		result, err := convertImage(input, width, height)
+		result, err := epd.ConvertImage(input, width, height)
 		if err != nil {
 			log.Fatalf("Could not convert image: %v", err)
 		}
@@ -78,58 +70,3 @@ func init() {
 	convertCmd.Flags().IntVarP(&height, "height", "y", 960, "target height")
 	convertCmd.Flags().StringVarP(&outfile, "output", "o", "", "file to write the result to (default stdout)")
 }
-
-// Returns a new Rectangle that is resized and centered in `dst`
-func fitRectInto(src *image.Rectangle, dst *image.Rectangle) image.Rectangle {
-	var targetWidth int
-	var targetHeight int
-	var scale float64
-
-	srcRatio := float64(src.Max.X) / float64(src.Max.Y)
-	dstRatio := float64(dst.Max.X) / float64(dst.Max.Y)
-
-	if srcRatio < dstRatio {
-		// center horizontally, scale vertically
-		scale = float64(dst.Max.Y) / float64(src.Max.Y)
-	} else {
-		// center vertically, scale horizontally
-		scale = float64(dst.Max.X) / float64(src.Max.X)
-	}
-
-	targetWidth = int(float64(src.Max.X) * scale)
-	targetHeight = int(float64(src.Max.Y) * scale)
-
-	targetX := (dst.Max.X - targetWidth) / 2
-	targetY := (dst.Max.Y - targetHeight) / 2
-
-	return image.Rect(targetX, targetY, targetWidth+targetX, targetHeight+targetY)
-}
-
-func convertImage(input io.Reader, width int, height int) ([]byte, error) {
-	src, _, err := image.Decode(input)
-	if err != nil {
-		return nil, err
-	}
-	dst := image.NewGray(image.Rect(0, 0, width, height))
-
-	srcBounds := src.Bounds()
-	targetRect := fitRectInto(&srcBounds, &dst.Rect)
-
-	draw.Draw(dst, dst.Bounds(), &image.Uniform{color.White}, image.ZP, draw.Src)
-	draw.CatmullRom.Scale(dst, targetRect, src, src.Bounds(), draw.Over, nil)
-
-	// the actual conversion works by packing two nibbles together in a byte
-	var result = make([]byte, (width*height+1)/2)
-	for i, p := range dst.Pix {
-		res := uint8((uint16(p) + 8) / 16)
-		if i%2 == 0 {
-			result[i/2] = (res << 4)
-		} else {
-			// note that integer division makes sure we're writing at the same
-			// index for odd and even indices
-			result[i/2] = result[i/2] | res
-		}
-	}
-
-	return result, nil
-}