fif/src/mimedb.rs

#[cfg(feature = "infer-backend")]
use std::str::FromStr;

use mime_guess::Mime;

pub trait MimeDb {
	fn init() -> Self;
	fn get_type(&self, data: &[u8]) -> Option<Mime>;
}

#[cfg(feature = "infer-backend")]
pub struct InferDb {
	db: infer::Infer,
}

#[cfg(feature = "infer-backend")]
impl MimeDb for InferDb {
	fn init() -> Self {
		let mut info = infer::Infer::new();
		// add a random file type just to make sure adding works and such
		info.add("image/jpeg2000", ".jp2", |buf| {
			buf.len() > 23
				&& buf[0] == 0x00
				&& buf[1] == 0x00
				&& buf[2] == 0x00
				&& buf[3] == 0x0C
				&& buf[4] == 0x6A
				&& buf[5] == 0x50
				&& buf[6] == 0x20
				&& buf[7] == 0x20
				&& buf[8] == 0x0D
				&& buf[9] == 0x0A
				&& buf[10] == 0x87
				&& buf[11] == 0x0A
				&& buf[20] == 0x6A
				&& buf[21] == 0x70
				&& buf[22] == 0x32
				&& buf[23] == 0x20
		});

		// unmut
		let info = info;

		Self { db: info }
	}

	fn get_type(&self, data: &[u8]) -> Option<Mime> {
		self.db.get(data).map(|f| Mime::from_str(f.mime_type()).unwrap())
	}
}

#[cfg(feature = "xdg-mime-backend")]
pub struct XdgDb {
	db: xdg_mime::SharedMimeInfo,
}

#[cfg(feature = "xdg-mime-backend")]
impl MimeDb for XdgDb {
	fn init() -> Self {
		Self {
			db: xdg_mime::SharedMimeInfo::new(),
		}
	}

	fn get_type(&self, data: &[u8]) -> Option<Mime> {
		self.db.get_mime_type_for_data(&data).map(|m| m.0)
	}
}