package api

import (
	"encoding/json"
	"net/http"
	"time"

	"git.freecumextremist.com/grumbulon/pomme/internal"
	"golang.org/x/crypto/bcrypt"
	"gorm.io/gorm"
)

// These are used for documentation, might be removed later
// nolint: unused
type httpError struct {
	Message string `json:"message" example:"Status bad request"`
	Code    int    `json:"code" example:"401"`
}

// nolint: unused
type httpSuccess struct {
	Message string `json:"message" example:"Success"`
	Code    int    `json:"code" example:"200"`
}

// nolint: unused
type httpInternalServerError struct {
	Message string `json:"message" example:"Internal Server Error"`
	Code    int    `json:"code" example:"500"`
}

// Auth godoc
//
//	@Summary		authenticate as a regular user
//	@Description	login to Pomme
//
//	@Description	Rate limited: 5 requests every 5 second
//
//	@Tags			accounts
//	@Accept			json
//	@Produce		json
//	@Param			username	query		string	true	"Username"
//	@Param			password	query		string	true	"Password"
//	@Success		200			{object}	httpSuccess
//	@Failure		401			{object}	httpError
//	@Router			/api/login [post]
func Login(w http.ResponseWriter, r *http.Request) {
	var result internal.User

	if _, err := r.Cookie("jwt"); err == nil {
		http.Error(w, "Logged in", http.StatusCreated)

		return
	}

	err := r.ParseForm()
	if err != nil {
		internalServerError(w, "unable to parse request")

		return
	}

	username := r.Form.Get("username")

	password := r.Form.Get("password")

	if username == "" {
		internalServerError(w, "no username provided") // this should prob be handled by the frontend

		return
	}

	if password == "" {
		internalServerError(w, "no password provided") // this should prob be handled by the frontend

		return
	}

	db, ok := r.Context().Value(keyPrincipalContextID).(*gorm.DB)
	if !ok {
		internalServerError(w, "DB connection failed")

		return
	}

	db.Where("username = ?", username).First(&result)

	if result.Username == "" {
		authFailed(w, "login")

		return
	}

	err = bcrypt.CompareHashAndPassword([]byte(result.HashedPassword), []byte(password))

	if err != nil {
		authFailed(w, "login")

		return
	}

	token, err := makeToken(username)
	if err != nil {
		internalServerError(w, err.Error())

		return
	}

	http.SetCookie(w, &http.Cookie{
		HttpOnly: true,
		Expires:  time.Now().Add(1 * time.Hour),
		MaxAge:   3600,
		SameSite: http.SameSiteLaxMode,
		// Uncomment below for HTTPS:
		// Secure: true,
		Name:  "jwt", // Must be named "jwt" or else the token cannot be searched for by jwtauth.Verifier.
		Value: token,
	})
	w.Header().Set("Content-Type", "application/json")
	err = json.NewEncoder(w).Encode(
		internal.Response{
			Message:      "Successfully logged in",
			HTTPResponse: 200,
		})

	if err != nil {
		internalServerError(w, "internal server error")

		return
	}

	http.Redirect(w, r, "/", http.StatusSeeOther)
}

// Logout destroys a users JWT cookie.
func Logout(w http.ResponseWriter, r *http.Request) {
	http.SetCookie(w, &http.Cookie{
		HttpOnly: true,
		MaxAge:   -1, // Delete the cookie.
		SameSite: http.SameSiteLaxMode,
		// Secure: true,
		Name:  "jwt",
		Value: "",
	})

	w.Header().Set("Content-Type", "application/json")

	err := json.NewEncoder(w).Encode(
		internal.Response{
			Message:      "Successfully logged out",
			HTTPResponse: 200,
		})
	if err != nil {
		internalServerError(w, "internal server error")

		return
	}

	http.Redirect(w, r, "/", http.StatusSeeOther)
}