hrynco-notification-service/HrynCo.NotificationService.Worker.Services/EmailProcessing/SendEmailMessageValidator.cs

namespace HrynCo.NotificationService.Worker.Services.EmailProcessing;

using System.Net.Mail;
using HrynCo.NotificationService.Contracts.Messages;

public static class SendEmailMessageValidator
{
    public static void Validate(SendEmailMessage message)
    {
        ArgumentNullException.ThrowIfNull(message);

        if (message.CorrelationContext is null)
            throw new InvalidDataException("CorrelationContext is required.");
        if (string.IsNullOrWhiteSpace(message.CorrelationContext.CorrelationId))
            throw new InvalidDataException("CorrelationContext.CorrelationId is required.");
        if (message.Data is null)
            throw new InvalidDataException("Data is required.");

        Require(message.Data.ServiceName, nameof(message.Data.ServiceName));
        Require(message.Data.TemplateKey, nameof(message.Data.TemplateKey));
        Require(message.Data.RecipientEmail, nameof(message.Data.RecipientEmail));
        Require(message.Data.RecipientName, nameof(message.Data.RecipientName));
        Require(message.Data.LanguageCode, nameof(message.Data.LanguageCode));

        if (!MailAddress.TryCreate(message.Data.RecipientEmail, out _))
            throw new InvalidDataException("RecipientEmail is not a valid email address.");
        if (message.Data.Variables is null)
            throw new InvalidDataException("Variables is required.");
    }

    private static void Require(string? value, string fieldName)
    {
        if (string.IsNullOrWhiteSpace(value))
            throw new InvalidDataException($"{fieldName} is required.");
    }
}