Adds the main program

main.go

@@ -0,0 +1,100 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"regexp"
+	"strconv"
+	"strings"
+	"text/template"
+)
+
+const latexTemplate = `\documentclass[a4paper]{article}
+\usepackage[pdftex]{color,graphicx,epsfig}
+\usepackage[final]{pdfpages}
+\begin{document}
+\includepdf[pages=-,nup=1x2,landscape,signature={{.Pages}}]{{printf "{"}}{{.FileName}}{{printf "}"}}
+\end{document}
+`
+
+type info struct {
+	Pages    int
+	FileName string
+}
+
+func check(e error) {
+	if e != nil {
+		panic(e)
+	}
+}
+
+func getNrPages(fileName string) int {
+	data, err := ioutil.ReadFile(fileName)
+	check(err)
+	lines := strings.Split(strings.Replace(string(data), "\r", "\n", -1), "\n")
+
+	re := regexp.MustCompile("^[^\\/]*\\/Count\\s(\\d+)")
+	for _, line := range lines {
+		if re.MatchString(line) {
+			match := re.FindStringSubmatch(line)
+			pages, err := strconv.Atoi(match[1])
+			check(err)
+			return pages
+		}
+	}
+	return 0
+}
+
+func generateLaTeX(inputFile string, outputFile string) {
+	t := template.New("latexTemplate")
+	t, err := t.Parse(latexTemplate)
+	check(err)
+
+	pages := 0
+	for pages < getNrPages(inputFile) {
+		pages += 4
+	}
+
+	f, err := os.Create(outputFile)
+	check(err)
+	defer f.Close()
+	w := bufio.NewWriter(f)
+
+	err = t.Execute(w, info{
+		Pages: pages,
+		FileName: strings.Replace(
+			strings.Replace(inputFile, "%", "\\%", -1),
+			"_", "\\_", -1),
+	})
+	w.Flush()
+}
+
+func compileAndClean(texFile string) {
+	c := exec.Command("latexmk", "-pdf", texFile)
+	check(c.Run())
+
+	c = exec.Command("latexmk", "-c", texFile)
+	check(c.Run())
+}
+
+func main() {
+	var outputFile string
+	if len(os.Args) < 2 {
+		fmt.Println("No arguments provided, use command in the form 'gobooklet [input] ([output])?'")
+		os.Exit(-1)
+	} else if len(os.Args) < 3 {
+		outputFile = os.Args[1]
+		outputFile = strings.TrimRight(outputFile, ".pdf")
+		outputFile = outputFile + "_booklet"
+	} else {
+		outputFile = os.Args[2]
+		outputFile = strings.TrimRight(outputFile, ".pdf")
+	}
+
+	generateLaTeX(os.Args[1], outputFile+".tex")
+	compileAndClean(outputFile + ".tex")
+	os.Remove(outputFile + ".tex")
+}