#region Copyright
// /************************************************************************
//    Copyright (c) 2016 Jamie Rees
//    File: UserMapper.cs
//    Created By: Jamie Rees
//   
//    Permission is hereby granted, free of charge, to any person obtaining
//    a copy of this software and associated documentation files (the
//    "Software"), to deal in the Software without restriction, including
//    without limitation the rights to use, copy, modify, merge, publish,
//    distribute, sublicense, and/or sell copies of the Software, and to
//    permit persons to whom the Software is furnished to do so, subject to
//    the following conditions:
//   
//    The above copyright notice and this permission notice shall be
//    included in all copies or substantial portions of the Software.
//   
//    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
//    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
//    LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
//    OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
//    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//  ************************************************************************/
#endregion
using System;
using System.Collections.Generic;
using System.Linq;
using System.Security;

using Nancy;
using Nancy.Authentication.Forms;
using Nancy.Security;

using PlexRequests.Core.Models;
using PlexRequests.Helpers;
using PlexRequests.Store;
using PlexRequests.Store.Repository;

namespace PlexRequests.Core
{
    public class UserMapper : IUserMapper, ICustomUserMapper
    {
        public UserMapper(IRepository<UsersModel> repo)
        {
            Repo = repo;
        }
        private static IRepository<UsersModel> Repo { get; set; }
        public IUserIdentity GetUserFromIdentifier(Guid identifier, NancyContext context)
        {
            var user = Repo.Get(identifier.ToString());

            if (user == null)
            {
                return null;
            }

            return new UserIdentity
            {
                UserName = user.UserName,
                Claims = ByteConverterHelper.ReturnObject<string[]>(user.Claims)
            };
        }

        public Guid? ValidateUser(string username, string password)
        {
            var users = Repo.GetAll();

            foreach (var u in users)
            {
                if (username == u.UserName)
                {
                    var passwordMatch = PasswordHasher.VerifyPassword(password, u.Salt, u.Hash);
                    if (passwordMatch)
                    {
                        return new Guid(u.UserGuid);
                    }
                }
            }
            return null;
        }

        public bool DoUsersExist()
        {
            var users = Repo.GetAll();

            return users.Any();
        }

        public Guid? CreateUser(string username, string password, string[] claims = default(string[]))
        {
            var salt = PasswordHasher.GenerateSalt();

            var userModel = new UsersModel
            {
                UserName = username,
                UserGuid = Guid.NewGuid().ToString(),
                Salt = salt,
                Hash = PasswordHasher.ComputeHash(password, salt),
                Claims = ByteConverterHelper.ReturnBytes(claims),
                UserProperties = ByteConverterHelper.ReturnBytes(new UserProperties())
            };
            Repo.Insert(userModel);

            var userRecord = Repo.Get(userModel.UserGuid);

            return new Guid(userRecord.UserGuid);
        }

        public bool UpdatePassword(string username, string oldPassword, string newPassword)
        {
            var users = Repo.GetAll();
            var userToChange = users.FirstOrDefault(x => x.UserName == username);
            if (userToChange == null)
                return false;

            var passwordMatch = PasswordHasher.VerifyPassword(oldPassword, userToChange.Salt, userToChange.Hash);
            if (!passwordMatch)
            {
                throw new SecurityException("Password does not match");
            }

            var newSalt = PasswordHasher.GenerateSalt();
            var newHash = PasswordHasher.ComputeHash(newPassword, newSalt);

            userToChange.Hash = newHash;
            userToChange.Salt = newSalt;

            return Repo.Update(userToChange);
        }

        public IEnumerable<UsersModel> GetUsers()
        {
            return Repo.GetAll();
        }
    }

    public interface ICustomUserMapper
    {
        IEnumerable<UsersModel> GetUsers();
        Guid? CreateUser(string username, string password, string[] claims = default(string[]));
        bool DoUsersExist();
        Guid? ValidateUser(string username, string password);
        bool UpdatePassword(string username, string oldPassword, string newPassword);

    }
}