package main

import (
	"compress/gzip"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	"net/url"
	"os"
	"path"
	"regexp"
	"strings"

	"github.com/gorilla/mux"
	"github.com/jbowtie/gokogiri/xml"
	"github.com/jbowtie/ratago/xslt"
)

type TOCNode struct {
	Name     string    `json:"name"`
	File     string    `json:"file,omitempty"`
	Key      string    `json:"id"`
	Children []TOCNode `json:"children,omitempty"`
}

type CarInfo struct {
	SoftLink url.Values            `json:"softlink"`
	ToC      []TOCNode             `json:"toc"`
	Values   map[string]url.Values `json:"tocpath"`
}

var indexList CarInfo

func main() {
	r := mux.NewRouter()
	r.PathPrefix("/static/").Handler(http.StripPrefix("/static", http.FileServer(http.Dir("html/static"))))
	r.HandleFunc("/cars", HomeHandler)
	r.HandleFunc("/{car}", CarHandler)
	r.HandleFunc("/file/{page}", PageHandler)
	r.HandleFunc("/img/{file}", ImgHandler)
	r.PathPrefix("/").Handler(http.FileServer(http.Dir("html")))
	err := http.ListenAndServe(":8080", r)
	if err != nil {
		log.Fatal("ListenAndServe: ", err)
	}
}

func HomeHandler(w http.ResponseWriter, r *http.Request) {
	body, _ := ioutil.ReadFile("Manuals/vehicles.json")
	w.Header().Set("Content-Type", "application/json")
	w.Write(body)

}

func CarHandler(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	folder := vars["car"]
	indexList = CarInfo{}
	file, err := os.Open(path.Join("Manuals", folder+".toc"))
	if err != nil {
		w.Header().Set("Content-Type", "application/json")
		empty := []TOCNode{TOCNode{Name: "Not Available", Key: "1"}}
		json.NewEncoder(w).Encode(empty)
		return
	}
	json.NewDecoder(file).Decode(&indexList)
	w.Header().Set("Content-Encoding", "gzip")
	w.Header().Set("Content-Type", "application/json")
	writer := gzip.NewWriter(w)
	json.NewEncoder(writer).Encode(indexList.ToC)
	writer.Close()

}

func PageHandler(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	img := vars["page"]
	style, _ := xml.ReadFile(path.Join("Manuals", "techauth.xsl"), xml.StrictParseOption)
	stylesheet, _ := xslt.ParseStylesheet(style, path.Join("Manuals", "techauth.xsl"))

	input, err := xml.ReadFile(path.Join("Manuals", "files", img), xml.StrictParseOption)
	if err != nil {
		http.NotFound(w, r)
		return
	}
	params := make(map[string]interface{})
	params["TOCPath"] = indexList.Values[img]["TOCPath"][0]
	params["modelyear"] = indexList.Values[img]["year"][0]
	params["modelname"] = indexList.Values[img]["platform"][0]
	params["ENG"] = indexList.Values[img]["ENG"][0]
	params["locale"] = indexList.Values[img]["lang"][0]
	params["vid"] = indexList.Values[img]["VID"][0]
	params["contentPath"] = "img/"
	output, err := stylesheet.Process(input, xslt.StylesheetOptions{false, params})
	if err != nil {
		fmt.Println(err)
	}
	if strings.Contains(output, "REPLACEME") {
		reg := regexp.MustCompile(`REPLACEME="(\d+?)"`)
		matches := reg.FindAllStringSubmatch(output, -1)
		for _, item := range matches {
			location := indexList.SoftLink[item[1]]
			if len(location) > 1 {
				string2 := FindToc(indexList.ToC, location[0])
				place, _ := json.Marshal(string2)
				output = strings.Replace(output, item[0], fmt.Sprintf(`v-on:click="app.switchToc('%s')"`, strings.Replace(string(place), `"`, `"`, -1)), -1)
			} else {
				output = strings.Replace(output, item[0], fmt.Sprintf(`v-on:click="app.index('%s')"`, location[0]), -1)
			}
		}
	}
	w.Write([]byte(output))
}

func ImgHandler(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	img := vars["file"]
	img = strings.Replace(img, ".tif", ".jpg", -1)
	http.ServeFile(w, r, path.Join("Manuals", "files", "img", img))
}

func FindToc(toc []TOCNode, file string) []string {
	var list []string
	for _, item := range toc {
		if item.File == file {
			list = append([]string{item.Key}, list...)
		}
		list2 := FindToc(item.Children, file)
		if len(list2) > 0 {
			list = append([]string{item.Key}, list2...)
		}

	}
	return list
}