use base64::decode;
use surf::{Body, Url};
use tide::{Request, Response};

pub async fn handler(req: Request<()>) -> tide::Result {
	let domains = vec![
		// THUMBNAILS
		"a.thumbs.redditmedia.com",
		"b.thumbs.redditmedia.com",
		// EMOJI
		"emoji.redditmedia.com",
		// ICONS
		"styles.redditmedia.com",
		"www.redditstatic.com",
		// PREVIEWS
		"preview.redd.it",
		"external-preview.redd.it",
		// MEDIA
		"i.redd.it",
		"v.redd.it",
	];

	let decoded = decode(req.param("url").unwrap_or_default()).map(|bytes| String::from_utf8(bytes).unwrap_or_default());

	match decoded {
		Ok(media) => match Url::parse(media.as_str()) {
			Ok(url) => {
				if domains.contains(&url.domain().unwrap_or_default()) {
					let http = surf::get(url).await.unwrap();

					let content_length = http.header("Content-Length").map(|v| v.to_string()).unwrap_or_default();
					let content_type = http.content_type().map(|m| m.to_string()).unwrap_or_default();

					Ok(
						Response::builder(http.status())
							.body(Body::from_reader(http, None))
							.header("Cache-Control", "public, max-age=1209600, s-maxage=86400")
							.header("Content-Length", content_length)
							.header("Content-Type", content_type)
							.build(),
					)
				} else {
					Err(tide::Error::from_str(403, "Resource must be from Reddit"))
				}
			}
			Err(_) => Err(tide::Error::from_str(400, "Can't parse base64 into URL")),
		},
		Err(_) => Err(tide::Error::from_str(400, "Can't decode base64")),
	}
}