using Microsoft.AspNetCore.Identity;
using System.Security.Claims;
using Microsoft.AspNetCore.Mvc.ApplicationModels;
using Finch.Identity;

namespace Finch.Identity;

public  class FinchRoleStore<TRole> :
  IRoleStore<TRole>, 
  IRoleClaimStore<TRole>
  where TRole : FinchIdentityRole, new()
{
  protected IdentityErrorDescriber ErrorDescriber { get; private set; }

  protected virtual IFinchIdentityStoreDbProvider Db { get; set; }


  public FinchRoleStore(IFinchIdentityStoreDbProvider db, IdentityErrorDescriber describer = null)
  {
    Db = db;
    ErrorDescriber = describer ?? new IdentityErrorDescriber();
  }


  private IdentityResult Fail(Result<TRole> result)
  {
    IdentityError[] errors = new IdentityError[result.Errors.Count];

    int index = 0;
    foreach (ResultError error in result.Errors)
    {
      string message = error.Message + "(key: " + error.Property + ")";
      errors[index++] = new() { Code = "finch/raven/500", Description = message };
    }

    return IdentityResult.Failed(errors);
  }


  /// <inheritdoc/>
  public async Task<IdentityResult> CreateAsync(TRole role, CancellationToken cancellationToken)
  {
    cancellationToken.ThrowIfCancellationRequested();

    if (role == null)
    {
      throw new ArgumentNullException(nameof(role));
    }

    try
    {
      Result<TRole> result =  await Db.Create(role);

      if (!result.IsSuccess)
      {
        return Fail(result);
      }
    }
    catch (Exception ex)
    {
      return IdentityResult.Failed(new IdentityError { Description = ex.Message });
    }

    return IdentityResult.Success;
  }


  /// <inheritdoc/>
  public async Task<IdentityResult> UpdateAsync(TRole role, CancellationToken cancellationToken)
  {
    Result<TRole> result = await Db.Update(role);
      
    if (!result.IsSuccess)
    {
      return Fail(result);
    }
    return IdentityResult.Success;
  }


  /// <inheritdoc/>
  public async Task<IdentityResult> DeleteAsync(TRole role, CancellationToken cancellationToken)
  {
    Result<TRole> result = await Db.Delete(role);
      
    if (!result.IsSuccess)
    {
      return Fail(result);
    }
    return IdentityResult.Success;
  }


  /// <inheritdoc/>
  public Task<string> GetRoleIdAsync(TRole role, CancellationToken cancellationToken) => Task.FromResult(role.Id);


  /// <inheritdoc/>
  public Task<string> GetRoleNameAsync(TRole role, CancellationToken cancellationToken) => Task.FromResult(role.Name);


  /// <inheritdoc/>
  public Task SetRoleNameAsync(TRole role, string roleName, CancellationToken cancellationToken)
  {
    role.Name = roleName;
    return Task.CompletedTask;
  }


  /// <inheritdoc/>
  public Task<string> GetNormalizedRoleNameAsync(TRole role, CancellationToken cancellationToken) 
    => Task.FromResult(role.Name);


  /// <inheritdoc/>
  public Task SetNormalizedRoleNameAsync(TRole role, string normalizedName, CancellationToken cancellationToken) =>
    SetRoleNameAsync(role, normalizedName, cancellationToken);


  /// <inheritdoc/>
  public async Task<TRole> FindByIdAsync(string roleId, CancellationToken cancellationToken)
  {
    // TODO index
    return await Db.Load<TRole>(roleId);
  }


  /// <inheritdoc/>
  public async Task<TRole> FindByNameAsync(string normalizedRoleName, CancellationToken cancellationToken)
  {
    // TODO index
    return await Db.Find<TRole>(x => x.Name == normalizedRoleName, cancellationToken);
  }


  /// <inheritdoc/>
  public void Dispose()
  {
      
  }


  /*
    * ****************************************************
    * CLAIM
    * ****************************************************
    */


  /// <inheritdoc/>
  public Task AddClaimAsync(TRole role, Claim claim, CancellationToken cancellationToken = default)
  {
    role.Claims.Add(new(claim));
    return Task.CompletedTask;
  }


  /// <inheritdoc/>
  public Task<IList<Claim>> GetClaimsAsync(TRole role, CancellationToken cancellationToken = default) =>
    Task.FromResult((IList<Claim>)role.Claims.Select(claim => claim.ToClaim()).ToList());


  /// <inheritdoc/>
  public Task RemoveClaimAsync(TRole role, Claim claim, CancellationToken cancellationToken = default)
  {
    UserClaim userClaim = new(claim);
    role.Claims = role.Claims.Except(new List<UserClaim>() { userClaim }, new UserClaimComparer()).ToList();
    return Task.CompletedTask;
  }
}