using FluentValidation.Results;
using Microsoft.AspNetCore.Identity;
using Newtonsoft.Json;
using Raven.Client.Documents;
using Raven.Client.Documents.Conventions;
using Raven.Client.Documents.Session;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using zero.Core.Entities;
using zero.Core.Entities.Setup;
using zero.Core.Identity;
using zero.Core.Validation;


namespace zero.Core.Api
{
  public class SetupApi : ISetupApi
  {
    protected IZeroConfiguration Config { get; private set; }

    protected UserManager<User> UserManager { get; private set; }


    public SetupApi(IZeroConfiguration config, UserManager<User> userManager)
    {
      Config = config;
      UserManager = userManager;
    }


    public async Task<EntityResult<SetupModel>> Install(SetupModel model)
    {
      ValidationResult validation = await new SetupModelValidator().ValidateAsync(model);

      if (!validation.IsValid)
      {
        return EntityResult<SetupModel>.Fail(validation);
      }

      DocumentStore raven = null;

      try
      {
        // test read & write permissions on folders
        // TODO

        // create temporary instance of database
        raven = new DocumentStore()
        {
          Urls = model.Database.Url.Split(','),
          Database = model.Database.Name
        };

        raven.Conventions.FindCollectionName = type =>
        {
          return Constants.Database.CollectionPrefix + DocumentConventions.DefaultGetCollectionName(type);
        };

        raven.Conventions.IdentityPartsSeparator = ".";

        raven.Initialize();

        // create application
        Application app = new Application()
        {
          CreatedDate = DateTimeOffset.Now,
          IsActive = true,
          Name = model.AppName,
          Alias = Alias.Generate(model.AppName)
        };

        // create user
        User user = new User()
        {
          IsSuper = true,
          CreatedDate = DateTimeOffset.Now,
          Email = model.User.Email,
          Name = model.User.Name,
          IsActive = true,
          LanguageId = Config.DefaultLanguage,
          Alias = Alias.Generate(model.User.Name),
          IsEmailConfirmed = true
        };

        IdentityResult result = await UserManager.CreateAsync(user, model.User.Password);

        // user creation failed
        if (!result.Succeeded)
        {
          EntityResult<SetupModel> entityResult = EntityResult<SetupModel>.Fail();

          foreach (IdentityError error in result.Errors)
          {
            entityResult.AddError(error.Code, error.Description);
          }

          return entityResult;
        }

        // save entities
        using (IAsyncDocumentSession session = raven.OpenAsyncSession())
        {
          await session.StoreAsync(app);

          // set app-id for user and store it
          user.AppId = session.Advanced.GetDocumentId(app);
          await session.StoreAsync(user);

          // save default user roles
          IList<UserRole> roles = GetRoles(model);

          foreach (UserRole role in roles)
          {
            await session.StoreAsync(role);
          }

          // add admin role to super user
          user.Roles.Add(roles.First(role => role.Name == "Standard").Alias);
          user.Roles.Add(roles.First(role => role.Name == "Administrator").Alias);

          // set countries
          using (Raven.Client.Documents.BulkInsert.BulkInsertOperation bulkInsert = raven.BulkInsert())
          {
            foreach (Country country in GetCountries(model))
            {
              await bulkInsert.StoreAsync(country);
            }
          }

          // update settings file. if this fails the changes won't be stored
          UpdateSettingsFile(model);

          await session.SaveChangesAsync();
        }
      }
      catch (Exception ex)
      {
        // TODO revert

        throw ex;
      }
      finally
      {
        raven?.Dispose();
      }

      return EntityResult<SetupModel>.Success(model);
    }


    /// <summary>
    /// Updates the settings file with the new data (database connection and version)
    /// </summary>
    void UpdateSettingsFile(SetupModel model)
    {
      var filePath = Path.Combine(model.ContentRootPath, "zeroSettings.json");
      string json = File.ReadAllText(filePath);

      ZeroConfiguration config = JsonConvert.DeserializeObject<ZeroConfiguration>(json);

      config.Raven = new RavenConfig()
      {
        Database = model.Database.Name,
        Url = model.Database.Url
      };

      config.ZeroVersion = System.Reflection.Assembly.GetEntryAssembly().GetName().Version.ToString();

      json = JsonConvert.SerializeObject(config, Formatting.Indented);

      File.WriteAllText(filePath, json);
    }


    /// <summary>
    /// Get countries for supported backoffice languages
    /// </summary>
    IList<Country> GetCountries(SetupModel model)
    {
      List<Country> countries = new List<Country>();

      string[] isoCodes = Config.SupportedLanguages;

      foreach (string languageISO in isoCodes)
      {
        // country list from: https://github.com/umpirsky/country-list/tree/master/data
        var filePath = Path.Combine(model.ContentRootPath, "Resources", "Countries", "countries." + languageISO.ToLowerInvariant() + ".json");
        string json = File.ReadAllText(filePath);


        countries.AddRange(JsonConvert.DeserializeObject<Dictionary<string, string>>(json).Select(country => new Country()
        {
          CreatedDate = DateTimeOffset.Now,
          IsActive = true,
          Alias = Alias.Generate(country.Key),
          LanguageId = languageISO,
          Code = country.Key,
          Name = country.Value
        }).ToList());
      }

      return countries;
    }


    /// <summary>
    /// Create default roles
    /// </summary>
    IList<UserRole> GetRoles(SetupModel model)
    {
      string type = Constants.Auth.Claims.Permission;

      UserRole adminRole = new UserRole()
      {
        Name = "Administrator",
        Alias = Alias.Generate("Administrator"),
        Sort = 0,
        AppId = Constants.Database.SharedAppId,
        Icon = "fth-award color-yellow",
        CreatedDate = DateTimeOffset.Now,
        IsActive = true,
        Claims = new List<IUserClaim>()
        {
          new UserClaim(type, Permissions.Applications, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Dashboard, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Lists, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Pages, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Media, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Settings, PermissionsValue.Write),
          new UserClaim(type, Permissions.Settings.Applications, PermissionsValue.None),
          new UserClaim(type, Permissions.Settings.Countries, PermissionsValue.Write),
          new UserClaim(type, Permissions.Settings.Logging, PermissionsValue.Write),
          new UserClaim(type, Permissions.Settings.Translations, PermissionsValue.Write),
          new UserClaim(type, Permissions.Settings.Updates, PermissionsValue.Write),
          new UserClaim(type, Permissions.Settings.Users, PermissionsValue.Write),
        },
      };

      UserRole editorRole = new UserRole()
      {
        Name = "Editor",
        Alias = Alias.Generate("Editor"),
        Sort = 1,
        AppId = Constants.Database.SharedAppId,
        Icon = "fth-feather",
        CreatedDate = DateTimeOffset.Now,
        IsActive = true,
        Claims = new List<IUserClaim>()
        {
          new UserClaim(type, Permissions.Sections.Dashboard, PermissionsValue.Read),
          new UserClaim(type, Permissions.Sections.Lists, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Pages, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Media, PermissionsValue.Write),
          new UserClaim(type, Permissions.Sections.Settings, PermissionsValue.Write),
          new UserClaim(type, Permissions.Settings.Translations, PermissionsValue.Write)
        }
      };

      UserRole defaultRole = new UserRole()
      {
        Name = "Standard",
        Alias = Alias.Generate("Standard"),
        Sort = 2,
        AppId = Constants.Database.SharedAppId,
        Icon = "fth-users",
        CreatedDate = DateTimeOffset.Now,
        IsActive = true,
        Claims = new List<IUserClaim>()
        {
          new UserClaim(type, Permissions.Sections.Dashboard, PermissionsValue.Read)
        }
      };

      return new List<UserRole>() { adminRole, editorRole, defaultRole };
    }
  }



  public interface ISetupApi
  {
    Task<EntityResult<SetupModel>> Install(SetupModel model);
  }
}