using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http.Headers;
using System.Security.Cryptography;
using System.Text;
using Xylem.Common.CommonCore.Configuration;
using Xylem.Common.Logic.SoftwareAccessHelper;

namespace Xylem.Common.Utils.UserAccessCtrl
{
    /// <summary>
    /// Holds information over current software and logged in user.
    /// </summary>
    public static class Software
    {
        const String Bearer = nameof(Bearer);

        private static String bearer;
        private static LDAPUser user;
        private static IEnumerable<SoftwareFunctions> softwareFunctions = Array.Empty<SoftwareFunctions>();

        public static String UserName { get; private set; }

        public static Boolean IsRegistrationPending { get; set; }

        public static LDAPUser PendingUser => user;

        public static Boolean IsAutenticated => !string.IsNullOrWhiteSpace(bearer);

        public static AuthenticationHeaderValue AuthorizationHeader
            = new AuthenticationHeaderValue(Bearer, bearer);

        public static void Initialize()
        {
            bearer = default(String);
            user = new LDAPUser();

            var version = SoftwareVersion.Current;
            var response = new LDAPLoginModel
            {
                Assembly = version.Name,
                BuildV = version.BuildV,
                MajorV = version.MajorV,
                MinorV = version.MinorV,
                EmployeeId = user.EmployeeId
            }
            .PostAsJson<String>($"{ServiceUrls.LaaProductionAPI}/LaaProductionWeb/API/Login/AD");

            if (response.HttpStatusCode == HttpStatusCode.Accepted)
            {
                IsRegistrationPending = true;
            }
            else if (response.HttpStatusCode == HttpStatusCode.OK)
            {
                bearer = response
                    .Value
                    ?.Trim()
                    ?.Trim('"');
                softwareFunctions = GetFunctions();

                if (!string.IsNullOrWhiteSpace(bearer))
                {
                    UserName = $"{user.FirstName} {user.LastName}";
                }
            }

            if (string.IsNullOrWhiteSpace(UserName))
            {
                UserName = "Options";
            }
        }

        internal static Boolean ChangePassword(String oldPassword, String newPassword, String confirmPassword, out Dictionary<String, String> errors)
        {
            errors = new Dictionary<String, String>();

            var response = new
            {
                OldPassword = oldPassword.ComputeBase64Hash(),
                NewPassword = newPassword.ComputeBase64Hash(),
                ConfirmPassword = confirmPassword.ComputeBase64Hash()
            }
            .PutAsJson<Dictionary<String, String>>($"{ServiceUrls.LaaProductionAPI}/LaaProductionWeb/API/Login", headers =>
            {
                headers.Authorization = $"{Bearer} {bearer}";
            });
            var succeeded = response.HttpStatusCode == HttpStatusCode.OK;

            if (!succeeded)
            {
                errors = response.Errors;
            }

            return succeeded;
        }

        internal static Boolean Register(LDAPUser user, out Dictionary<String, String> errors)
        {
            errors = new Dictionary<String, String>();

            var version = SoftwareVersion.Current;
            var response = new LDAPRegisterModel
            {
                Assembly = version.Name,
                BuildV = version.BuildV,
                ConfirmPassword = user.ConfirmPassword,
                DomainName = user.DomainName,
                Email = user.Email,
                EmployeeId = user.EmployeeId,
                FirstName = user.FirstName,
                LastName = user.LastName,
                MajorV = version.MajorV,
                MinorV = version.MinorV,
                Password = user.Password,
                Phone = user.Phone,
                Username = user.Username
            }
            .PutAsJson<String>($"{ServiceUrls.LaaProductionAPI}/LaaProductionWeb/API/Login/AD");
            var succeeded = response.HttpStatusCode == HttpStatusCode.OK;

            if (succeeded)
            {
                IsRegistrationPending = false;

                bearer = response
                    ?.Value
                    ?.Trim()
                    ?.Trim('"');
                softwareFunctions = GetFunctions();

                if (!string.IsNullOrWhiteSpace(bearer))
                {
                    UserName = $"{user.FirstName} {user.LastName}";
                }
            }
            else
            {
                errors = response.Errors;
            }

            return succeeded;
        }

        /// <summary>
        /// Sends login request and obtains an bearer authorization token.
        /// </summary>
        public static Boolean Login(String username, String password, out Dictionary<String, String> errors)
        {
            bearer = default(String);
            errors = new Dictionary<String, String>();

            var response = new UserLoginModel
            {
                Username = username,
                Password = password,
                Assembly = SoftwareVersion.Current.Name,
                MajorV = SoftwareVersion.Current.MajorV,
                MinorV = SoftwareVersion.Current.MinorV,
                BuildV = SoftwareVersion.Current.BuildV,
            }
            .PostAsJson<String>($"{ServiceUrls.LaaProductionAPI}/LaaProductionWeb/API/Login/Local");

            if (response.HttpStatusCode == HttpStatusCode.OK)
            {
                bearer = response
                    .Value
                    ?.Trim()
                    ?.Trim('"');
                softwareFunctions = GetFunctions();

                if (!string.IsNullOrWhiteSpace(bearer))
                {
                    UserName = $"{ServiceUrls.LaaProductionAPI}/LaaProductionWeb/API/Login"
                        .GetAsJson<String>(headersHandler: headers =>
                        {
                            headers.Authorization = $"{Bearer} {bearer}";
                        })
                        .Value;
                }
            }
            else
            {
                errors = response.Errors;
            }

            if (string.IsNullOrWhiteSpace(UserName))
            {
                UserName = "Options";
            }

            return !string.IsNullOrWhiteSpace(bearer);
        }

        public static IEnumerable<SoftwareFunctions> GetFunctions()
        {
            if (string.IsNullOrWhiteSpace(bearer))
            {
                return Array.Empty<SoftwareFunctions>();
            }

            try
            {
                var response = $"{ServiceUrls.LaaProductionAPI}/LaaProductionWeb/API/Personalization/Software/Access"
                    .GetAsJson<IEnumerable<SoftwareFunctions>>(headersHandler: headers =>
                    {
                        headers.Authorization = $"{Bearer} {bearer}";
                    });

                return response.Value;
            }
            catch (Exception e)
            {
                Console.WriteLine(e);

                return Array.Empty<SoftwareFunctions>();
            }
        }

        public static Boolean IsEnabled(SoftwareFunctions softwareFunction)
            => softwareFunction != SoftwareFunctions.NONE && softwareFunctions.Contains(softwareFunction);

        public static void Logout()
        {
            UserName = "Options";
            bearer = default(String);
            softwareFunctions = Array.Empty<SoftwareFunctions>();

            //Initialize();
        }

        internal static String ComputeBase64Hash(this String plainText)
        {
            if (string.IsNullOrWhiteSpace(plainText))
            {
                return plainText;
            }

            var buffer = Encoding.UTF8.GetBytes(plainText);
            var hash = SHA256.Create().ComputeHash(buffer);

            return Convert.ToBase64String(hash);
        }
    }
}