package auth

import (
	"dk/internal/cookies"
	"dk/internal/helpers"
	"dk/internal/models/users"
	"dk/internal/router"
	"dk/internal/session"
	"fmt"
	"time"

	"github.com/valyala/fasthttp"
)

const SessionCookieName = "dk_session"

func Middleware() router.Middleware {
	return func(next router.Handler) router.Handler {
		return func(ctx router.Ctx, params []string) {
			sessionID := cookies.GetCookie(ctx, SessionCookieName)
			var sess *session.Session

			if sessionID != "" {
				if existingSess, exists := session.Get(sessionID); exists {
					sess = existingSess
					sess.Touch()

					if sess.UserID > 0 { // User session
						user, err := users.Find(sess.UserID)
						if err == nil && user != nil {
							ctx.SetUserValue("user", user)
						} else {
							// User not found, reset to guest session
							sess.SetUserID(0)
						}
					}
					session.Store(sess)
					setSessionCookie(ctx, sessionID)
				}
			}

			// Create guest session if none exists
			if sess == nil {
				sess = session.Create(0) // Guest session
				setSessionCookie(ctx, sess.ID)
			}

			ctx.SetUserValue("session", sess)
			next(ctx, params)
		}
	}
}

func RequireAuth(paths ...string) router.Middleware {
	redirect := "/login"
	if len(paths) > 0 && paths[0] != "" {
		redirect = paths[0]
	}

	return func(next router.Handler) router.Handler {
		return func(ctx router.Ctx, params []string) {
			if !IsAuthenticated(ctx) {
				ctx.Redirect(redirect, fasthttp.StatusFound)
				return
			}

			user := ctx.UserValue("user").(*users.User)
			user.UpdateLastOnline()
			user.Save()

			next(ctx, params)
		}
	}
}

func RequireGuest(paths ...string) router.Middleware {
	redirect := "/"
	if len(paths) > 0 && paths[0] != "" {
		redirect = paths[0]
	}

	return func(next router.Handler) router.Handler {
		return func(ctx router.Ctx, params []string) {
			if IsAuthenticated(ctx) {
				fmt.Println("RequireGuest: user is authenticated")
				ctx.Redirect(redirect, fasthttp.StatusFound)
				return
			}
			next(ctx, params)
		}
	}
}

func IsAuthenticated(ctx router.Ctx) bool {
	if user, ok := ctx.UserValue("user").(*users.User); ok && user != nil {
		return true
	}
	return false
}

func GetCurrentUser(ctx router.Ctx) *users.User {
	if user, ok := ctx.UserValue("user").(*users.User); ok {
		return user
	}
	return nil
}

func GetCurrentSession(ctx router.Ctx) *session.Session {
	if sess, ok := ctx.UserValue("session").(*session.Session); ok {
		return sess
	}
	return nil
}

func Login(ctx router.Ctx, user *users.User) {
	sess := ctx.UserValue("session").(*session.Session)

	// Update the session to be authenticated
	sess.SetUserID(user.ID) // This updates the struct field
	sess.RegenerateID()     // Generate new ID for security
	sess.SetFlash("success", fmt.Sprintf("Welcome back, %s!", user.Username))

	// Remove any old user_id from session data if it exists
	sess.Delete("user_id")

	session.Store(sess)

	// Update context values
	ctx.SetUserValue("session", sess)
	ctx.SetUserValue("user", user)

	// Update cookie with new session ID
	setSessionCookie(ctx, sess.ID)
}

func Logout(ctx router.Ctx) {
	sess := ctx.UserValue("session").(*session.Session)
	if sess != nil {
		// Convert back to guest session
		sess.SetUserID(0)   // Reset to guest
		sess.RegenerateID() // Generate new ID for security

		// Clean up any user-related session data
		sess.Delete("user_id")

		session.Store(sess)
		ctx.SetUserValue("session", sess)

		// Update cookie with new session ID
		setSessionCookie(ctx, sess.ID)
	}

	ctx.SetUserValue("user", nil)
}

// Helper functions for session cookies
func setSessionCookie(ctx router.Ctx, sessionID string) {
	cookies.SetSecureCookie(ctx, cookies.CookieOptions{
		Name:     SessionCookieName,
		Value:    sessionID,
		Path:     "/",
		Expires:  time.Now().Add(24 * time.Hour),
		HTTPOnly: true,
		Secure:   helpers.IsHTTPS(ctx),
		SameSite: "lax",
	})
}

func deleteSessionCookie(ctx router.Ctx) {
	cookies.DeleteCookie(ctx, SessionCookieName)
}