package main

import (
	"crypto/sha512"
	"encoding/json"
	"fmt"
	"log"
	"strconv"
	"strings"

	"github.com/fasthttp/router"
	"github.com/valyala/fasthttp"
	"github.com/xujiajun/nutsdb"
)

func RunWebserv() {
	r := router.New()
	r.GET("/", Start)
	r.GET("/api/season", Season)
	r.GET("/api/watch/{user?}", WatchGet)
	r.POST("/api/register", Register)
	r.POST("/api/watch/{user}", WatchPost)
	r.PATCH("/api/watch/{user}", Start)
	r.DELETE("/api/watch/{user}", Start)
	log.Fatal(fasthttp.ListenAndServe(":"+strconv.Itoa(*webServerPort), r.Handler))
}

func Start(ctx *fasthttp.RequestCtx) {
	data, err := cache.Get(seasonApiJikan)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}
	var seasonData SeasonJikan
	err = json.Unmarshal(data, &seasonData)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}

	WriteIndex(ctx, &seasonData)

	ctx.SetContentType("text/html; charset=utf-8")
	ctx.SetStatusCode(fasthttp.StatusOK)
}

func Season(ctx *fasthttp.RequestCtx) {
	data, err := cache.Get(seasonApiJikan)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}
	var seasonData SeasonJikan
	err = json.Unmarshal(data, &seasonData)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}

	_, err = ctx.Write(data)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}

	ctx.SetContentType("application/json; charset=utf-8")
	ctx.SetStatusCode(fasthttp.StatusOK)
}

func WatchGet(ctx *fasthttp.RequestCtx) {
	usrVal := ctx.UserValue("user")
	var userId int64
	if usrVal != nil {
		// check user exists
		user, err := ReadUser(fmt.Sprintf("%s", usrVal))
		if err != nil {
			ctx.WriteString("Dich gibts nicht")
			ctx.SetStatusCode(fasthttp.StatusNotFound)
			return
		}
		userId = user.MalID
	}
	animes, err := ReadAnimes()
	if err != nil {
		// check if no anime were inserted
		if err != nutsdb.ErrBucketEmpty {
			addErrorToCtx(ctx, err)
			return
		}
		animes = make([]Anime, 0)
	}

	// apply single user logic
	if usrVal != nil {
		filteredAnimes := make([]Anime, 0)
		for _, a := range animes {
			for _, u := range a.Users {
				if u.MalID == userId {
					filteredAnimes = append(filteredAnimes, a)
					break
				}
			}
		}
		animes = filteredAnimes
	}

	bytes, err := json.Marshal(animes)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}
	_, err = ctx.Write(bytes)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}

	ctx.SetContentType("application/json; charset=utf-8")
	ctx.SetStatusCode(fasthttp.StatusOK)
}

func Register(ctx *fasthttp.RequestCtx) {
	if string(ctx.Request.Header.ContentType()) != "application/json" {
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		return
	}
	body := ctx.PostBody()
	var register RegisterData
	err := json.Unmarshal(body, &register)
	if err != nil {
		ctx.WriteString(err.Error())
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		return
	}
	if register.MalID == 0 || register.Username == "" || register.Secret == "" || register.Sauce == "" {
		ctx.WriteString("Sprich JSON du Hurensohn")
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		return
	}

	calcSauce := fmt.Sprintf("%x", sha512.Sum512([]byte(registerSecret+strconv.FormatInt(register.MalID, 10)+register.Username)))
	if calcSauce != strings.ToLower(register.Sauce) {
		ctx.WriteString("Möge die Sauce mit dir sein")
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		return
	}
	// check user exists
	_, err = ReadUser(register.Username)
	if err == nil {
		ctx.WriteString("Nicht drängeln")
		ctx.SetStatusCode(fasthttp.StatusConflict)
		return
	}
	// check user legit
	userData, _, err := GetUserData(register.Username)
	if err != nil {
		ctx.WriteString(err.Error())
		ctx.SetStatusCode(fasthttp.StatusExpectationFailed)
		return
	}
	if userData.Data.MalID != register.MalID {
		ctx.WriteString("Dich gibts nicht auf MAL")
		ctx.SetStatusCode(fasthttp.StatusExpectationFailed)
		return
	}
	// REGISTER
	user := UserData{
		Username: register.Username,
		MalID:    register.MalID,
		Secret:   register.Secret,
	}
	err = SaveUser(&user)
	if err != nil {
		addErrorToCtx(ctx, err)
		return
	}

	ctx.SetBody(body)
	ctx.SetStatusCode(fasthttp.StatusOK)
}

func WatchPost(ctx *fasthttp.RequestCtx) {
	//
}

func addErrorToCtx(ctx *fasthttp.RequestCtx, err error) {
	ctx.WriteString(err.Error())
	ctx.SetStatusCode(fasthttp.StatusInternalServerError)
}