//   Sofaraum server is the server which collects the statistics
//   for the sofaraum-heatmap application.
//   Copyright 2018 K.Langenberg and contributors. All rights reserved.
//
//   This program is free software: you can redistribute it and/or modify
//   it under the terms of the GNU General Public License as published by
//   the Free Software Foundation, either version 3 of the License, or
//   (at your option) any later version.
//
//   This program is distributed in the hope that it will be useful,
//   but WITHOUT ANY WARRANTY; without even the implied warranty of
//   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//   GNU General Public License for more details.
//
//   You should have received a copy of the GNU General Public License
//   along with this program.  If not, see <https://www.gnu.org/licenses/>.

package models

import (
	"golang.org/x/crypto/bcrypt"
)

// CreateUser creates a new user and inserts it into the database
func CreateUser(user *User) (newUser *User, err error) {

	newUser = user

	// Check if we have all needed informations
	if newUser.Password == "" || newUser.Username == "" {
		return &User{}, ErrNoUsernamePassword{}
	}

	// Check if the user already existst with that username
	var exists = true
	existingUser, err := GetUser(&User{Username: newUser.Username})
	if err != nil {
		if IsErrUserDoesNotExist(err) {
			exists = false
		} else {
			return &User{}, err
		}
	}
	if exists {
		return &User{}, ErrUsernameExists{newUser.ID, newUser.Username}
	}

	// Check if the user already existst with that email
	if newUser.Email != "" {
		existingUser, err = GetUser(&User{Email: newUser.Email})
		if err != nil {
			if IsErrUserDoesNotExist(err) {
				exists = false
			} else {
				return &User{}, err
			}
		}
		if exists {
			return &User{}, ErrUserEmailExists{existingUser.ID, existingUser.Email}
		}
	}

	// Hash the password
	newUser.Password, err = hashPassword(user.Password)
	if err != nil {
		return &User{}, err
	}

	newUser.IsActive = true

	// Insert it
	_, err = x.Insert(newUser)
	if err != nil {
		return &User{}, err
	}

	return newUser, err
}

// HashPassword hashes a password
func hashPassword(password string) (string, error) {
	bytes, err := bcrypt.GenerateFromPassword([]byte(password), 14)
	return string(bytes), err
}

// UpdateUser updates a user
func UpdateUser(user *User) (updatedUser *User, err error) {

	// Check if it exists
	theUser, err := GetUserByID(user.ID)
	if err != nil {
		return &User{}, err
	}

	// Check if we have at least a username
	if user.Username == "" {
		//return User{}, ErrNoUsername{user.ID}
		user.Username = theUser.Username // Dont change the username if we dont have one
	}

	user.Password = theUser.Password // set the password to the one in the database to not accedently resetting it

	// Update it
	_, err = x.Id(user.ID).Update(user)
	if err != nil {
		return &User{}, err
	}

	// Get the newly updated user
	updatedUser, err = GetUserByID(user.ID)
	if err != nil {
		return &User{}, err
	}

	return updatedUser, err
}

// UpdateUserPassword updates the password of a user
func UpdateUserPassword(user *User, newPassword string) (err error) {

	// Get all user details
	theUser, err := GetUserByID(user.ID)
	if err != nil {
		return err
	}

	// Hash the new password and set it
	hashed, err := hashPassword(newPassword)
	if err != nil {
		return err
	}
	theUser.Password = hashed

	// Update it
	_, err = x.Id(user.ID).Update(theUser)
	if err != nil {
		return err
	}

	return err
}