package main

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"sync"

	"github.com/99designs/keyring"
	"github.com/wailsapp/wails/v2/pkg/runtime"
)

var simklJwt SimklJWT

var simklRing, _ = keyring.Open(keyring.Config{
	ServiceName: "AniTrack",
})

var simklCtxShutdown, simklCancel = context.WithCancel(context.Background())

func (a *App) CheckIfSimklLoggedIn() bool {
	if (SimklJWT{} == simklJwt) {
		tokenType, err := simklRing.Get("SimklTokenType")
		accessToken, err := simklRing.Get("SimklAccessToken")
		scope, err := simklRing.Get("SimklScope")
		if err != nil || len(accessToken.Data) == 0 {
			return false
		} else {
			simklJwt.TokenType = string(tokenType.Data)
			simklJwt.AccessToken = string(accessToken.Data)
			simklJwt.Scope = string(scope.Data)
			return true
		}
	} else {
		return true
	}
}

func (a *App) SimklLogin() {
	if a.CheckIfSimklLoggedIn() == false {
		tokenType, err := simklRing.Get("SimklTokenType")
		accessToken, err := simklRing.Get("SimklAccessToken")
		scope, err := simklRing.Get("SimklScope")
		if err != nil || len(accessToken.Data) == 0 {
			getSimklCodeUrl := "https://simkl.com/oauth/authorize?response_type=code&client_id=" + os.Getenv("SIMKL_CLIENT_ID") + "&redirect_uri=" + os.Getenv("SIMKL_CALLBACK_URI")
			runtime.BrowserOpenURL(a.ctx, getSimklCodeUrl)

			serverDone := &sync.WaitGroup{}
			serverDone.Add(1)
			handleSimklCallback(serverDone)
			serverDone.Wait()
		} else {
			simklJwt.TokenType = string(tokenType.Data)
			simklJwt.AccessToken = string(accessToken.Data)
			simklJwt.Scope = string(scope.Data)
		}
	}
}

func handleSimklCallback(wg *sync.WaitGroup) {
	mux := http.NewServeMux()
	srv := &http.Server{Addr: ":6734", Handler: mux}
	mux.HandleFunc("/callback", func(w http.ResponseWriter, r *http.Request) {
		select {
		case <-simklCtxShutdown.Done():
			fmt.Println("Shutting down...")
			return
		default:
		}
		content := r.FormValue("code")

		if content != "" {
			simklJwt = getSimklAuthorizationToken(content)
			_ = simklRing.Set(keyring.Item{
				Key:  "SimklTokenType",
				Data: []byte(simklJwt.TokenType),
			})
			_ = simklRing.Set(keyring.Item{
				Key:  "SimklAccessToken",
				Data: []byte(simklJwt.AccessToken),
			})
			_ = simklRing.Set(keyring.Item{
				Key:  "SimklScope",
				Data: []byte(simklJwt.Scope),
			})
			fmt.Println("Shutting down...")
			simklCancel()
			err := srv.Shutdown(context.Background())
			if err != nil {
				log.Println("server.Shutdown:", err)
			}
		} else {
			_, err := fmt.Fprintf(w, "Getting code failed.")
			if err != nil {
				return
			}
		}
	})

	go func() {
		defer wg.Done()
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("listen: %s\n", err)
		}
		fmt.Println("Shutting down...")
	}()
}

func getSimklAuthorizationToken(content string) SimklJWT {
	data := struct {
		GrantType    string `json:"grant_type"`
		ClientID     string `json:"client_id"`
		ClientSecret string `json:"client_secret"`
		RedirectURI  string `json:"redirect_uri"`
		Code         string `json:"code"`
	}{
		GrantType:    "authorization_code",
		ClientID:     os.Getenv("SIMKL_CLIENT_ID"),
		ClientSecret: os.Getenv("SIMKL_CLIENT_SECRET"),
		RedirectURI:  os.Getenv("SIMKL_CALLBACK_URI"),
		Code:         content,
	}
	jsonData, err := json.Marshal(data)
	if err != nil {
		log.Fatal(err)
	}

	response, err := http.NewRequest("POST", "https://api.simkl.com/oauth/token", bytes.NewBuffer(jsonData))
	if err != nil {
		log.Printf("Failed at response, %s\n", err)
	}
	response.Header.Add("Content-Type", "application/json")

	client := &http.Client{}
	res, reserr := client.Do(response)
	if reserr != nil {
		log.Printf("Failed at res, %s\n", err)
	}

	defer res.Body.Close()

	returnedBody, err := io.ReadAll(res.Body)

	var post SimklJWT
	err = json.Unmarshal(returnedBody, &post)
	if err != nil {
		log.Printf("Failed at unmarshal, %s\n", err)
	}

	return post
}

func (a *App) GetSimklLoggedInUser() SimklUser {
	a.SimklLogin()

	client := &http.Client{}

	req, _ := http.NewRequest("POST", "https://api.simkl.com/users/settings", nil)

	req.Header.Add("Content-Type", "application/json")
	req.Header.Add("Authorization", "Bearer "+simklJwt.AccessToken)
	req.Header.Add("simkl-api-key", os.Getenv("SIMKL_CLIENT_ID"))

	response, err := client.Do(req)

	if err != nil {
		log.Printf("Failed at request, %s\n", err)
		return SimklUser{}
	}

	defer response.Body.Close()

	var user SimklUser

	respBody, _ := io.ReadAll(response.Body)

	err = json.Unmarshal(respBody, &user)
	if err != nil {
		log.Printf("Failed at unmarshal, %s\n", err)
	}

	return user
}