Add user avatar and profile feature, consolidate Auth and UserManagement features (#257)

web/backend/Features/Features.Users/Commands/Authentication/RegisterUser/RegisterUserValidator.cs

@@ -0,0 +1,63 @@
+using FluentValidation;
+
+namespace Features.Auth.Commands.Authentication.RegisterUser;
+
+/// <summary>
+///     Validates the field-level constraints on <see cref="RegisterUserCommand" />: username format and
+///     length, name lengths, email format, minimum age of 19, and password complexity.
+/// </summary>
+public class RegisterUserValidator : AbstractValidator<RegisterUserCommand>
+{
+    public RegisterUserValidator()
+    {
+        RuleFor(x => x.Username)
+            .NotEmpty()
+            .WithMessage("Username is required")
+            .Length(3, 64)
+            .WithMessage("Username must be between 3 and 64 characters")
+            .Matches("^[a-zA-Z0-9._-]+$")
+            .WithMessage(
+                "Username can only contain letters, numbers, dots, underscores, and hyphens"
+            );
+
+        RuleFor(x => x.FirstName)
+            .NotEmpty()
+            .WithMessage("First name is required")
+            .MaximumLength(128)
+            .WithMessage("First name cannot exceed 128 characters");
+
+        RuleFor(x => x.LastName)
+            .NotEmpty()
+            .WithMessage("Last name is required")
+            .MaximumLength(128)
+            .WithMessage("Last name cannot exceed 128 characters");
+
+        RuleFor(x => x.Email)
+            .NotEmpty()
+            .WithMessage("Email is required")
+            .EmailAddress()
+            .WithMessage("Invalid email format")
+            .MaximumLength(128)
+            .WithMessage("Email cannot exceed 128 characters");
+
+        RuleFor(x => x.DateOfBirth)
+            .NotEmpty()
+            .WithMessage("Date of birth is required")
+            .LessThan(DateTime.Today.AddYears(-19))
+            .WithMessage("You must be at least 19 years old to register");
+
+        RuleFor(x => x.Password)
+            .NotEmpty()
+            .WithMessage("Password is required")
+            .MinimumLength(8)
+            .WithMessage("Password must be at least 8 characters")
+            .Matches("[A-Z]")
+            .WithMessage("Password must contain at least one uppercase letter")
+            .Matches("[a-z]")
+            .WithMessage("Password must contain at least one lowercase letter")
+            .Matches("[0-9]")
+            .WithMessage("Password must contain at least one number")
+            .Matches("[^a-zA-Z0-9]")
+            .WithMessage("Password must contain at least one special character");
+    }
+}