Program.cs

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Hosting;
using MimeKit;
using System.IO;
using System.Linq;

var builder = WebApplication.CreateBuilder(args);

// Minimal API + Swagger only
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

var app = builder.Build();

if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

// FIX: Remove the [ValidateAntiForgeryToken] metadata by disabling antiforgery for this endpoint.
// Add .DisableAntiforgery() to the endpoint mapping.
app.MapPost("/api/emlparser/parse", async ([FromBody] EmlParserApi.EmlFileRequest request) =>
{
    if (request == null || string.IsNullOrEmpty(request.Base64Content))
        return Results.BadRequest("File content is missing.");

    // Convert base64 to stream
    var bytes = Convert.FromBase64String(request.Base64Content);
    using var stream = new MemoryStream(bytes);

    // Load MIME message
    var message = MimeKit.MimeMessage.Load(stream);

    // Extract attachments
    var attachments = message.Attachments.Select(a =>
    {
        using var ms = new MemoryStream();
        if (a is MimeKit.MimePart part)
            part.Content.DecodeTo(ms);
        else if (a is MimeKit.MessagePart rfc822)
            rfc822.Message.WriteTo(ms);

        return new
        {
            FileName = a.ContentDisposition?.FileName ?? a.ContentType.Name,
            Base64Content = Convert.ToBase64String(ms.ToArray())
        };
    }).ToList();

    var result = new
    {
        From = message.From.ToString(),
        To = message.To.ToString(),
        Subject = message.Subject,
        Date = message.Date.ToString(),
        BodyText = message.TextBody,
        BodyHtml = message.HtmlBody,
        Attachments = attachments
    };

    return Results.Ok(result);
})
.Accepts<EmlParserApi.EmlFileRequest>("application/json")
.Produces(StatusCodes.Status200OK)
.Produces(StatusCodes.Status400BadRequest)
.DisableAntiforgery();


app.Run();