use bytes::{Bytes, Buf};
use std::io::Cursor;

use ser::DnsPacketData;
use errors::*;

#[derive(Clone, Debug)]
pub struct HexShortBlob(Bytes);

// Similar to `ShortText`, but uses (unquoted, no spaces allowed) hex
// for text representation; "-" when empty
impl DnsPacketData for HexShortBlob {
	fn deserialize(data: &mut Cursor<Bytes>) -> Result<Self> {
		check_enough_data!(data, 1, "HexShortBlob length");
		let label_len = data.get_u8() as usize;
		check_enough_data!(data, label_len, "HexShortBlob content");
		let pos = data.position() as usize;
		let text = data.get_ref().slice(pos, pos + label_len);
		data.advance(label_len);
		Ok(HexShortBlob(text))
	}
}

#[derive(Clone, Debug)]
pub struct Base32ShortBlob(Bytes);

// Similar to `ShortText`, but uses (unquoted, no spaces allowed) base32
// for text representation; "-" when empty
impl DnsPacketData for Base32ShortBlob {
	fn deserialize(data: &mut Cursor<Bytes>) -> Result<Self> {
		check_enough_data!(data, 1, "Base32ShortBlob length");
		let label_len = data.get_u8() as usize;
		check_enough_data!(data, label_len, "Base32ShortBlob content");
		let pos = data.position() as usize;
		let text = data.get_ref().slice(pos, pos + label_len);
		data.advance(label_len);
		Ok(Base32ShortBlob(text))
	}
}

#[derive(Clone, Debug)]
pub struct LongText(Vec<Bytes>);

// RFC 1035 names this `One or more <character-string>`. No following
// field allowed.
impl DnsPacketData for LongText {
	fn deserialize(data: &mut Cursor<Bytes>) -> Result<Self> {
		let mut texts = Vec::new();
		loop {
			check_enough_data!(data, 1, "LongText length");
			let label_len = data.get_u8() as usize;
			check_enough_data!(data, label_len, "LongText content");
			let pos = data.position() as usize;
			texts.push(data.get_ref().slice(pos, pos + label_len));
			data.advance(label_len);
			if !data.has_remaining() { break; }
		}
		Ok(LongText(texts))
	}
}

#[derive(Clone, Debug)]
pub struct RemainingText(Bytes);

// No length byte, just all data to end of record. uses base64 encoding
// for text representation
impl DnsPacketData for RemainingText {
	fn deserialize(data: &mut Cursor<Bytes>) -> Result<Self> {
		let pos = data.position() as usize;
		let len = data.remaining();
		let text = data.get_ref().slice(pos, pos + len);
		data.advance(len);
		Ok(RemainingText(text))
	}
}

#[derive(Clone, Debug)]
pub struct HexRemainingBlob(Bytes);

// No length byte, just all data to end of record. uses hex encoding for
// text representation (spaces are ignored - last field in record).
impl DnsPacketData for HexRemainingBlob {
	fn deserialize(data: &mut Cursor<Bytes>) -> Result<Self> {
		let pos = data.position() as usize;
		let len = data.remaining();
		let text = data.get_ref().slice(pos, pos + len);
		data.advance(len);
		Ok(HexRemainingBlob(text))
	}
}