// Copyright 2023 wanderer <a_mirre at utb dot cz>
// SPDX-License-Identifier: AGPL-3.0-only

package handlers

import (
	"context"
	"errors"
	"net/http"

	"git.dotya.ml/mirre-mt/pcmt/ent"
	moduser "git.dotya.ml/mirre-mt/pcmt/modules/user"
	"github.com/gorilla/sessions"
	"github.com/labstack/echo-contrib/session"
	"github.com/labstack/echo/v4"
)

func Signup() echo.HandlerFunc {
	return func(c echo.Context) error {
		defer addHeaders(c)

		sess, _ := session.Get(setting.SessionCookieName(), c)
		if sess != nil {
			if uname, ok := sess.Values["username"].(string); ok && uname != "" {
				return c.Redirect(http.StatusFound, "/home")
			}
		}

		csrf := c.Get("csrf").(string)
		p := newPage()

		p.Title = "Sign up"
		p.Current = "signup"
		p.CSRF = csrf

		err := c.Render(
			http.StatusOK,
			"signup.tmpl",
			p,
		)
		if err != nil {
			log.Warnf("error: %q", err)

			return renderErrorPage(
				c,
				http.StatusInternalServerError,
				http.StatusText(http.StatusInternalServerError),
				err.Error(),
			)
		}

		return nil
	}
}

func SignupPost(client *ent.Client) echo.HandlerFunc {
	return func(c echo.Context) error {
		defer addHeaders(c)

		cu := new(userSignup)
		if err := c.Bind(cu); err != nil {
			return renderErrorPage(
				c,
				http.StatusBadRequest,
				http.StatusText(http.StatusBadRequest),
				err.Error(),
			)
		}

		if cu.Username == "" || cu.Email == "" || cu.Password == "" {
			c.Logger().Error("username or email or password not set, returning to /singup")
			return c.Redirect(http.StatusFound, "/singup")
		}

		if err := c.Validate(cu); err != nil {
			return renderErrorPage(
				c,
				http.StatusBadRequest,
				http.StatusText(http.StatusBadRequest)+" - "+ErrValidationFailed.Error(),
				err.Error(),
			)
		}

		username := cu.Username
		email := cu.Email
		passwd := cu.Password

		ctx := context.WithValue(context.Background(), moduser.CtxKey{}, slogger)

		exists, err := moduser.Exists(ctx, client, username, email)
		if err != nil {
			c.Logger().Error("error checking whether user exists", err)

			return renderErrorPage(
				c,
				http.StatusInternalServerError,
				http.StatusText(http.StatusInternalServerError),
				err.Error(),
			)
		}

		if exists {
			c.Logger().Error("username/email already taken")

			return c.Redirect(http.StatusSeeOther, "/signup")
		}

		u, err := moduser.CreateUser(
			ctx,
			client,
			email,
			username,
			passwd,
		)
		if err != nil {
			if errors.Is(err, errors.New("username is not unique")) {
				c.Logger().Error("username already taken")
				// TODO: re-render signup page with a flash message
				// stating what went wrong.
				return c.Redirect(http.StatusSeeOther, "/signup")
			}

			return renderErrorPage(
				c,
				http.StatusInternalServerError,
				http.StatusText(http.StatusInternalServerError)+" - failed to create schema resources",
				err.Error(),
			)
		}

		log.Infof("successfully registered user '%s'", u.Username)
		log.Debug("user details", "id", u.ID, "email", u.Email, "isAdmin", u.IsAdmin)

		sess, _ := session.Get(setting.SessionCookieName(), c)
		sess.Options = &sessions.Options{
			Path:     "/",
			MaxAge:   setting.SessionMaxAge(),
			HttpOnly: true,
			Secure:   setting.HTTPSecure(),
			SameSite: http.SameSiteStrictMode,
		}
		sess.Values["username"] = username

		err = sess.Save(c.Request(), c.Response())
		if err != nil {
			c.Logger().Error("failed to save session")

			return renderErrorPage(
				c,
				http.StatusInternalServerError,
				http.StatusText(http.StatusInternalServerError)+" (make sure you've got cookies enabled)",
				err.Error(),
			)
		}

		return c.Redirect(http.StatusMovedPermanently, "/home")
	}
}