game-ideas/src/GameIdeas/Server/GameIdeas.WebAPI/Services/Users/UserWriteService.cs

using AutoMapper;
using GameIdeas.Resources;
using GameIdeas.Shared.Dto;
using GameIdeas.Shared.Model;
using GameIdeas.WebAPI.Exceptions;
using Microsoft.AspNetCore.Identity;

namespace GameIdeas.WebAPI.Services.Users;

public class UserWriteService(
    UserManager<User> userManager) : IUserWriteService
{
    public async Task<string> CreateUser(UserDto user)
    {
        if (user.Username == null || 
            user.Password == null || 
            user.Role == null)
        {
            throw new UserInvalidException(ResourcesKey.MissingField);
        }

        User userToCreate = new() { UserName = user.Username };

        var result = await userManager.CreateAsync(userToCreate, user.Password);

        if (result.Succeeded)
        {
            await userManager.AddToRoleAsync(userToCreate, user.Role.Name);
        }
        else
        {
            throw new UserInvalidException(string.Join("; ", result.Errors.Select(e => $"{e.Code} {e.Description}")));
        }

        return userToCreate.Id;
    }

    public async Task<string> DeleteUser(string userId)
    {
        if (userId == null)
        {
            throw new ArgumentNullException(ResourcesKey.MissingField);
        }

        var user = await userManager.FindByIdAsync(userId)
            ?? throw new UserInvalidException("User not found");

        await userManager.DeleteAsync(user);
        return userId;
    }

    public async Task<string> UpdateUser(string userId, UserDto user)
    {
        if (userId == null)
        {
            throw new ArgumentNullException(ResourcesKey.MissingField);
        }

        var userToUpdate = await userManager.FindByIdAsync(userId)
            ?? throw new UserInvalidException("User not found");

        if (user.Username != null)
        {
            userToUpdate.UserName = user.Username;
            await userManager.UpdateAsync(userToUpdate);
        }

        if (user.Password != null)
        {
            await userManager.RemovePasswordAsync(userToUpdate);
            await userManager.AddPasswordAsync(userToUpdate, user.Password);
        }

        if (user.Role != null)
        {
            var roles = await userManager.GetRolesAsync(userToUpdate);
            await userManager.RemoveFromRolesAsync(userToUpdate, roles);
            await userManager.AddToRoleAsync(userToUpdate, user.Role.Name);  
        }

        return userToUpdate.Id;
    }
}