package webserver

import (
	"math/rand"

	irc "git.martyn.berlin/martyn/karaokards/internal/irc"
	"github.com/gorilla/handlers"
	"github.com/gorilla/mux"

	"encoding/json"
	"fmt"
	"html/template"
	"io/ioutil"
	"net/http"
	"net/url"
	"os"
	"strings"
	"time"
)

//var store = sessions.NewCookieStore(os.Getenv("SESSION_KEY"))

type twitchauthresponse struct {
	Access_token  string   `json: "access_token"`
	Expires_in    int      `json: "expires_in"`
	Refresh_token string   `json: "refresh_token"`
	Scope         []string `json: "scope"`
	Token_type    string   `json: "token_type"`
}

type twitchUser struct {
	Id                string `json: "id"`
	Login             string `json: "login"`
	Display_name      string `json: "display_name"`
	Type              string `json: "type"`
	Broadcaster_type  string `json: "affiliate"`
	Description       string `json: "description"`
	Profile_image_url string `json: "profile_image_url"`
	Offline_image_url string `json: "offline_image_url"`
	View_count        int    `json: "view_count"`
}

type twitchUsersBigResponse struct {
	Data []twitchUser `json:"data"`
}

var ircBot *irc.KardBot

func HealthHandler(response http.ResponseWriter, request *http.Request) {
	response.Header().Add("Content-type", "text/plain")
	fmt.Fprint(response, "I'm okay jack!")
}

func NotFoundHandler(response http.ResponseWriter, request *http.Request) {
	response.Header().Add("X-Template-File", "html"+request.URL.Path)
	response.WriteHeader(404)
	tmpl := template.Must(template.ParseFiles("web/404.html"))
	tmpl.Execute(response, nil)
}

func CSSHandler(response http.ResponseWriter, request *http.Request) {
	response.Header().Add("Content-type", "text/css")
	tmpl := template.Must(template.ParseFiles("web/cover.css"))
	tmpl.Execute(response, nil)
}

func RootHandler(response http.ResponseWriter, request *http.Request) {
	request.URL.Path = "/index.html"
	TemplateHandler(response, request)
}

func TemplateHandler(response http.ResponseWriter, request *http.Request) {
	response.Header().Add("X-Template-File", "web"+request.URL.Path)
	type TemplateData struct {
		Prompt       string
		AvailCount   int
		ChannelCount int
		MessageCount int
		ClientID     string
		BaseURI      string
	}
	// tmpl, err := template.New("html"+request.URL.Path).Funcs(template.FuncMap{
	// 	"ToUpper": strings.ToUpper,
	// 	"ToLower": strings.ToLower,
	// }).ParseFiles("html"+request.URL.Path)
	_ = strings.ToLower("Hello")
	if strings.Index(request.URL.Path, "/") < 0 {
		http.Error(response, "No slashes wat - "+request.URL.Path, http.StatusInternalServerError)
		return
	}

	basenameSlice := strings.Split(request.URL.Path, "/")
	basename := basenameSlice[len(basenameSlice)-1]
	//fmt.Fprintf(response, "%q", basenameSlice)
	tmpl, err := template.New(basename).Funcs(template.FuncMap{
		"ToUpper": strings.ToUpper,
		"ToLower": strings.ToLower,
	}).ParseFiles("web" + request.URL.Path)
	if err != nil {
		http.Error(response, err.Error(), http.StatusInternalServerError)
		return
		// NotFoundHandler(response, request)
		// return
	}
	var td = TemplateData{ircBot.Prompts[rand.Intn(len(ircBot.Prompts))], len(ircBot.Prompts), ircBot.ActiveChannels(), 0, ircBot.AppCredentials.ClientID, "https://" + ircBot.Config.ExternalUrl}
	err = tmpl.Execute(response, td)
	if err != nil {
		http.Error(response, err.Error(), http.StatusInternalServerError)
		return
	}
}

func LeaveHandler(response http.ResponseWriter, request *http.Request) {
	request.URL.Path = "/bye.html"
	TemplateHandler(response, request)
}

func AdminHandler(response http.ResponseWriter, request *http.Request) {
	vars := mux.Vars(request)
	if vars["key"] != ircBot.ChannelData[vars["channel"]].AdminKey {
		UnauthorizedHandler(response, request)
		return
	}
	type TemplateData struct {
		Channel      string
		Command      string
		ExtraStrings string
		SinceTime    time.Time
		SinceTimeUTC string
		Leaving      bool
		HasLeft      bool
	}
	channelData := ircBot.ChannelData[vars["channel"]]
	var td = TemplateData{channelData.Name, channelData.Command, channelData.ExtraStrings, channelData.JoinTime, channelData.JoinTime.Format(irc.UTCFormat), false, channelData.HasLeft}

	if request.Method == "POST" {
		request.ParseForm()
		if strings.Join(request.PostForm["leave"], ",") == "Leave twitch channel" {
			td.Leaving = true
		} else if strings.Join(request.PostForm["reallyleave"], ",") == "Really leave twitch channel" {
			record := ircBot.ChannelData[vars["channel"]]
			record.HasLeft = true
			ircBot.ChannelData[vars["channel"]] = record
			ircBot.LeaveChannel(vars["channel"])
			ircBot.Database.Write("channelData", vars["channel"], record)
			LeaveHandler(response, request)
			return
		}
		if strings.Join(request.PostForm["join"], ",") == "Come on in" {
			record := ircBot.ChannelData[vars["channel"]]
			td.HasLeft = false
			record.Name = vars["channel"]
			record.JoinTime = time.Now()
			record.HasLeft = false
			if record.Command == "" {
				record.Command = "card"
			}
			ircBot.Database.Write("channelData", vars["channel"], record)
			ircBot.ChannelData[vars["channel"]] = record
			td = TemplateData{record.Name, record.Command, record.ExtraStrings, record.JoinTime, record.JoinTime.Format(irc.UTCFormat), false, record.HasLeft}
			ircBot.JoinChannel(record.Name)
		}
		sourceData := ircBot.ChannelData[vars["channel"]]
		if strings.Join(request.PostForm["Command"], ",") != "" {
			sourceData.Command = strings.Join(request.PostForm["Command"], ",")
			td.Command = sourceData.Command
			ircBot.ChannelData[vars["channel"]] = sourceData
		}
		if strings.Join(request.PostForm["ExtraStrings"], ",") != sourceData.ExtraStrings {
			sourceData.ExtraStrings = strings.Join(request.PostForm["ExtraStrings"], ",")
			td.ExtraStrings = sourceData.ExtraStrings
			ircBot.ChannelData[vars["channel"]] = sourceData
		}
		ircBot.Database.Write("channelData", vars["channel"], sourceData)
	}
	tmpl := template.Must(template.ParseFiles("web/admin.html"))
	tmpl.Execute(response, td)
}

func UnauthorizedHandler(response http.ResponseWriter, request *http.Request) {
	response.Header().Add("X-Template-File", "html"+request.URL.Path)
	response.WriteHeader(401)
	tmpl := template.Must(template.ParseFiles("web/401.html"))
	tmpl.Execute(response, nil)
}

func twitchHTTPClient(call string, bearer string) (string, error) {
	url := "https://api.twitch.tv/helix/" + call
	var bearerHeader = "Bearer " + bearer

	req, err := http.NewRequest("GET", url, nil)
	req.Header.Add("Authorization", bearerHeader)

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	body, _ := ioutil.ReadAll(resp.Body)
	return string([]byte(body)), nil
}

func TwitchAdminHandler(response http.ResponseWriter, request *http.Request) {

	vars := mux.Vars(request)
	if vars["code"] != "" {
		response.Header().Add("Content-type", "text/plain")
		resp, err := http.PostForm(
			"https://id.twitch.tv/oauth2/token",
			url.Values{
				"client_id":     {ircBot.AppCredentials.ClientID},
				"client_secret": {ircBot.AppCredentials.Password},
				"code":          {vars["code"]},
				"grant_type":    {"authorization_code"},
				"redirect_uri":  {"https://" + ircBot.Config.ExternalUrl + "/twitchadmin"}})
		if err != nil {
			response.WriteHeader(500)
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: "+err.Error())
			return
		}

		defer resp.Body.Close()
		body, err := ioutil.ReadAll(resp.Body)
		if err != nil {
			response.WriteHeader(500)
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: "+err.Error())
			return
		}

		var oauthResponse twitchauthresponse
		err = json.Unmarshal(body, &oauthResponse)
		if err != nil {
			response.WriteHeader(500)
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: "+err.Error())
			return
		}

		usersResponse, err := twitchHTTPClient("users", oauthResponse.Access_token)
		if err != nil {
			response.WriteHeader(500)
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: "+err.Error())
			return
		}

		var usersObject twitchUsersBigResponse
		err = json.Unmarshal([]byte(usersResponse), &usersObject)
		if err != nil {
			response.WriteHeader(500)
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: "+err.Error())
			return
		}

		if len(usersObject.Data) != 1 {
			response.WriteHeader(500)
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: Twitch returned not 1 user for the request!\n---\n")
			fmt.Fprint(response, usersObject.Data)
			return
		}

		user := usersObject.Data[0]

		magicCode := ircBot.ReadOrCreateChannelKey(user.Login)
		url := "https://" + ircBot.Config.ExternalUrl + "/admin/" + user.Login + "/" + magicCode
		http.Redirect(response, request, url, http.StatusFound)

	} else {

		fmt.Fprintf(response, "I'm not okay jack! %v \n", vars)
		for key, val := range vars {
			fmt.Fprint(response, "%s = %s\n", key, val)
		}
	}
}

func TwitchBackendHandler(response http.ResponseWriter, request *http.Request) {
	response.Header().Add("Content-type", "text/plain")
	vars := mux.Vars(request)
	// fmt.Fprintf(response, "I'm okay jack! %v \n", vars)
	// for key, val := range(vars) {
	// 	fmt.Fprint(response, "%s = %s\n", key, val)
	// }

	if vars["code"] != "" {
		// https://id.twitch.tv/oauth2/token
		// ?client_id=<your client ID>
		// &client_secret=<your client secret>
		// &code=<authorization code received above>
		// &grant_type=authorization_code
		// &redirect_uri=<your registered redirect URI>

		// ircBot.AppCredentials.ClientID
		// ircBot.AppCredentials.Password
		// vars["oauthtoken"]
		// authorization_code
		// "https://"+ircBot.Config.ExternalUrl+/twitchadmin
		fmt.Println("Asking twitch for more...")
		resp, err := http.PostForm(
			"https://id.twitch.tv/oauth2/token",
			url.Values{
				"client_id":     {ircBot.AppCredentials.ClientID},
				"client_secret": {ircBot.AppCredentials.Password},
				"code":          {vars["code"]},
				"grant_type":    {"authorization_code"},
				"redirect_uri":  {"https://" + ircBot.Config.ExternalUrl + "/twitchadmin"}})
		if err != nil {
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: "+err.Error())
		}
		defer resp.Body.Close()
		body, err := ioutil.ReadAll(resp.Body)
		if err != nil {
			response.Header().Add("Content-type", "text/plain")
			fmt.Fprint(response, "ERROR: "+err.Error())
		}
		response.Header().Add("Content-type", "text/plain")
		fmt.Fprint(response, string(body))
	} else {
		UnauthorizedHandler(response, request)
	}
}

func HandleHTTP(passedIrcBot *irc.KardBot) {
	ircBot = passedIrcBot
	r := mux.NewRouter()
	loggedRouter := handlers.LoggingHandler(os.Stdout, r)
	r.NotFoundHandler = http.HandlerFunc(NotFoundHandler)
	r.HandleFunc("/", RootHandler)
	r.HandleFunc("/healthz", HealthHandler)
	r.HandleFunc("/web/{.*}", TemplateHandler)
	r.PathPrefix("/static/").Handler(http.FileServer(http.Dir("./web/")))
	r.HandleFunc("/cover.css", CSSHandler)
	r.HandleFunc("/admin/{channel}/{key}", AdminHandler)
	//r.HandleFunc("/twitchadmin", TwitchAdminHandler)
	//r.HandleFunc("/twitchtobackend", TwitchBackendHandler)
	r.Path("/twitchtobackend").Queries("access_token", "{access_token}", "scope", "{scope}", "token_type", "{token_type}").HandlerFunc(TwitchBackendHandler)
	r.Path("/twitchadmin").Queries("code", "{code}", "scope", "{scope}").HandlerFunc(TwitchAdminHandler)
	http.Handle("/", r)
	srv := &http.Server{
		Handler:      loggedRouter,
		Addr:         "0.0.0.0:5353",
		WriteTimeout: 15 * time.Second,
		ReadTimeout:  15 * time.Second,
	}
	fmt.Println("Listening on 0.0.0.0:5353")
	srv.ListenAndServe()
}