namespace HrynCo.NotificationService.Worker.Services.EmailProcessing;

using System.Text;
using HrynCo.NotificationService.Contracts.Messages;
using HrynCo.NotificationService.DAL.Abstract.Templates;

internal sealed class EmailTemplateRenderingService : IEmailTemplateRenderingService
{
    public RenderedEmail Render(EmailTemplate template, SendEmailMessageData data)
    {
        return new RenderedEmail(
            Interpolate(template.Subject, data.Variables),
            Interpolate(template.HtmlBody, data.Variables),
            Interpolate(template.TextBody, data.Variables));
    }

    private static string Interpolate(string text, IReadOnlyDictionary<string, string> variables)
    {
        var sb = new StringBuilder(text);
        foreach (var (key, value) in variables)
            sb.Replace($"{{{{{key}}}}}", value);
        return sb.ToString();
    }
}