package main

import (
	"fmt"
	"html/template"
	"os"
	"path/filepath"
	"regexp"

	"gopkg.in/gographics/imagick.v3/imagick"
)

type Talk struct {
	Title   string
	Preview string
	Path    string
}

func generatePreview(path string) Talk {
	r := regexp.MustCompile("talks\\/(.*)\\.pdf")
	result := r.FindStringSubmatch(path)
	imagePath := fmt.Sprintf("previews/%s.jpg", result[1])
	mw := imagick.NewMagickWand()
	defer mw.Destroy()
	mw.ReadImage(path)
	mw.SetIteratorIndex(0)
	mw.SetImageFormat("jpg")
	mw.WriteImage(imagePath)
	return Talk{Title: result[1], Preview: imagePath, Path: path}
}

func main() {

	var files []string

	root := "talks/"
	err := filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
		if info.IsDir() {
			return nil
		}
		files = append(files, path)
		return nil
	})
	if err != nil {
		panic(err)
	}

	imagick.Initialize()
	defer imagick.Terminate()
	var data []Talk
	for _, file := range files {
		t := generatePreview(file)
		data = append(data, t)
	}

	tmpl, err := template.ParseFiles("template.html")
	if err != nil {
		panic(err)
	}

	f, err := os.Create("index.html")
	if err != nil {
		panic(err)
	}
	defer f.Close()

	tmpl.Execute(f, data)
}