Add controller for login

src/GameIdeas/Server/GameIdeas.WebAPI/Controllers/UserController.cs

@@ -0,0 +1,54 @@
+using GameIdeas.Resources;
+using GameIdeas.Shared.Constants;
+using GameIdeas.Shared.Dto;
+using GameIdeas.Shared.Model;
+using Microsoft.AspNetCore.Identity;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.IdentityModel.Tokens;
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using System.Text;
+
+namespace GameIdeas.WebAPI.Controllers;
+
+public class UserController(UserManager<User> userManager) : Controller
+{
+    [HttpPost("login")]
+    public async Task<ActionResult<TokenDto>> Login([FromBody] UserDto model)
+    {
+        if (model.Username == null || model.Password == null)
+            throw new ArgumentNullException(paramName: nameof(model), ResourcesKey.UserArgumentsNull);
+
+        var user = await userManager.FindByNameAsync(model.Username);
+
+        if (user != null && await userManager.CheckPasswordAsync(user, model.Password))
+        {
+            List<Claim> authClaims =
+            [
+                new Claim(ClaimTypes.Name, user.UserName ?? string.Empty),
+                new Claim(JwtRegisteredClaimNames.Jti, Guid.NewGuid().ToString()),
+            ];
+
+            var jwtKey = Environment.GetEnvironmentVariable("JWT_KEY")
+                ?? throw new ArgumentNullException(message: ResourcesKey.InvalidToken, null);
+
+            var authSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(jwtKey));
+
+            var token = new JwtSecurityToken(
+                issuer: Environment.GetEnvironmentVariable("JWT_ISSUER"),
+                audience: Environment.GetEnvironmentVariable("JWT_AUDIENCE"),
+                expires: DateTime.Now.AddHours(GlobalConstants.JWT_DURATION_HOUR),
+                claims: authClaims,
+                signingCredentials: new SigningCredentials(authSigningKey, SecurityAlgorithms.HmacSha256)
+            );
+
+            return Ok(new TokenDto
+            {
+                Token = new JwtSecurityTokenHandler().WriteToken(token),
+                Expiration = token.ValidTo
+            });
+        }
+
+        return Unauthorized();
+    }
+}