package api

import (
	"encoding/json"
	"io"
	"log"
	"net/http"

	authdiscord "example.com/auth/discord"
	configserver "example.com/config/server"
	databasecommands "example.com/database/commands"
	databasemodels "example.com/database/models"

	"github.com/gin-gonic/gin"
	"github.com/xyproto/randomstring"
	"golang.org/x/oauth2"
	"gorm.io/gorm"
)

var GlobalDatabase *gorm.DB
var GlobalConfig configserver.AppConfig
var GlobalOAuth *oauth2.Config

func LoginRedirect(context *gin.Context) {
	context.Redirect(302, GlobalOAuth.AuthCodeURL(context.GetString("state")))
}

func LogoutRedirect(context *gin.Context) {
	oauthTokenJSON, err := context.Cookie("discord-oauthtoken")
	if err == nil {
		databasecommands.LogoutDatabaseUser(GlobalDatabase, oauthTokenJSON)
		context.SetCookie("discord-oauthtoken", "", -1, "", GlobalConfig.API.Domain, false, true)
	} else {
		log.Println(err)
	}
	context.Redirect(http.StatusTemporaryRedirect, "http://localhost:15995/")
}

func AuthCallback(context *gin.Context) {
	oauthState := randomstring.CookieFriendlyString(32)
	context.Set("state", oauthState)
	var err error
	oauthToken, err := GlobalOAuth.Exchange(context.Request.Context(), context.Query("code"))
	if err != nil {
		context.Redirect(http.StatusInternalServerError, "http://localhost:15995/")
	}
	oauthTokenJSON, _ := json.Marshal(oauthToken)
	context.SetCookie("discord-oauthtoken", string(oauthTokenJSON), 0, "", GlobalConfig.API.Domain, false, false)
	user := GetDiscordUser(context, oauthToken)
	CreateOrUpdateUser(context, oauthToken, user)
	context.Redirect(http.StatusTemporaryRedirect, "http://localhost:15995/dashboard")
}

func GetDiscordUser(context *gin.Context, oauthToken *oauth2.Token) authdiscord.DiscordUser {
	response, err := GlobalOAuth.Client(context.Request.Context(), oauthToken).Get("https://discord.com/api/users/@me")
	if err != nil || response.StatusCode != 200 {
		responseMessage := ""
		if err != nil {
			responseMessage = err.Error()
		} else {
			responseMessage = response.Status
		}
		context.JSON(http.StatusInternalServerError, gin.H{
			"message": responseMessage,
		})
	}
	defer response.Body.Close()
	body, err := io.ReadAll(response.Body)
	if err != nil {
		context.JSON(http.StatusInternalServerError, gin.H{
			"message": err.Error(),
		})
	}
	var user authdiscord.DiscordUser
	json.Unmarshal(body, &user)
	return user
}

func CreateOrUpdateUser(context *gin.Context, oauthToken *oauth2.Token, user authdiscord.DiscordUser) {
	oauthTokenJSON, err := json.Marshal(oauthToken)
	if err != nil {
		log.Println(err)
	}
	dbUser := databasemodels.User{
		DisplayName:      user.Global_Name,
		Username:         user.Username,
		Id:               user.Id,
		Avatar:           user.Avatar,
		AvatarDecoration: user.Avatar_Decoration_Data.Asset,
		LoginToken:       string(oauthTokenJSON),
		LoggedIn:         true,
	}
	if databasecommands.DatabaseUserExists(GlobalDatabase, user.Id) {
		dbOAuthToken := databasecommands.GetDatabaseUserToken(GlobalDatabase, user.Id)
		if dbOAuthToken == "" {
			context.SetCookie("discord-oauthtoken", string(oauthTokenJSON), 0, "", GlobalConfig.API.Domain, false, false)
			err := databasecommands.UpdateDatabaseUser(GlobalDatabase, dbUser)
			if err != nil {
				log.Println(err)
			}
		} else {
			context.SetCookie("discord-oauthtoken", dbOAuthToken, 0, "", GlobalConfig.API.Domain, false, false)
		}
	} else {
		err := databasecommands.CreateDatabaseUser(GlobalDatabase, dbUser)
		if err != nil {
			log.Println(err)
		}
	}
}

func GetDashboardInfo(context *gin.Context) {
	oauthTokenJSON, err := context.Cookie("discord-oauthtoken")
	if err == nil {
		var oauthToken *oauth2.Token
		err := json.Unmarshal([]byte(oauthTokenJSON), &oauthToken)
		if err == nil {
			if oauthToken.Valid() {
				user := GetDiscordUser(context, oauthToken)
				if databasecommands.DatabaseUserLoggedIn(GlobalDatabase, user.Id) {
					context.JSON(http.StatusOK, user)
					return
				} else {
					context.Redirect(http.StatusTemporaryRedirect, "http://localhost:31337/logout")
				}
				return
			}
		} else {
			log.Println(err)
		}
	} else {
		log.Println(err)
	}
	context.Redirect(http.StatusTemporaryRedirect, "http://localhost:15995/")
}

func IsUserAuthorized(context *gin.Context) {
	oauthTokenJSON, err := context.Cookie("discord-oauthtoken")
	if err == nil {
		var oauthToken *oauth2.Token
		err := json.Unmarshal([]byte(oauthTokenJSON), &oauthToken)
		if err == nil {
			if oauthToken.Valid() {
				user := GetDiscordUser(context, oauthToken)
				if databasecommands.DatabaseUserLoggedIn(GlobalDatabase, user.Id) {
					context.JSON(http.StatusOK, gin.H{
						"message": true,
					})
				} else {
					context.JSON(http.StatusUnauthorized, gin.H{
						"message": true,
					})
				}
				return
			} else {
				log.Println(err)
			}
		} else {
			log.Println(err)
		}
	} else {
		log.Println(err)
	}
	context.JSON(http.StatusUnauthorized, gin.H{
		"message": false,
	})
}