using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;

namespace MailSharp.MailClient.Controllers;

// Serves only the page shells - all data (folders, messages, translations, sending mail) is
// fetched client-side from Controllers/Api via mail.js / compose.js. Must stay reachable while
// logged out (mail.js itself redirects to /Account/Login on a 401 from the API), and since
// MapControllers() and MapControllerRoute() share the same endpoint data source,
// RequireAuthorization() on the API routes would otherwise leak onto this controller too.
[AllowAnonymous]
public class MailController : Controller
{
	[HttpGet]
	public IActionResult Index() => View();

	[HttpGet]
	public IActionResult Compose() => View();

	// Interstitial every link inside a rendered message HTML body gets rewritten to point at (see
	// ImageSanitizer.ApplyLinkPolicy) - lets the user confirm before a sender-controlled URL
	// actually runs, and opens in a real top-level tab instead of the sandboxed message iframe so
	// no destination site can refuse to be framed. 404s rather than open-redirecting on anything
	// that isn't a well-formed http(s) URL, since url is attacker-influenced (it's copied straight
	// out of an email).
	[HttpGet]
	public IActionResult ExternalLink(string url)
	{
		if (!Uri.TryCreate(url, UriKind.Absolute, out var parsed) ||
			(parsed.Scheme != Uri.UriSchemeHttp && parsed.Scheme != Uri.UriSchemeHttps))
		{
			return NotFound();
		}

		ViewData["ExternalUrl"] = parsed.AbsoluteUri;
		ViewData["ExternalHost"] = parsed.Host;
		return View();
	}
}