use crate::common_types::*;
use crate::errors::*;
use std::net::{Ipv4Addr, Ipv6Addr};

use crate::ser::{packet::DnsPacketData, text::DnsTextData, RRData};

// unless otherwise documented, class should probably be IN (0x0001)

// deriving RRData will add a unit test to make sure the type is
// registered; there must be a records::types::$name `Type` constant
// with the same name as the struct.

#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(IN)]
pub struct A {
	pub addr: Ipv4Addr,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct NS {
	pub nsdname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct MD {
	pub madname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct MF {
	pub madname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct CNAME {
	pub cname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct SOA {
	pub mname: DnsCompressedName,
	pub rname: DnsCompressedName,
	pub serial: u32,
	pub refresh: u32,
	pub retry: u32,
	pub expire: u32,
	pub minimum: u32,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct MB {
	pub madname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct MG {
	pub mgmname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct MR {
	pub newname: DnsCompressedName,
}

// not allowed in zone files anyway, i.e. no text representation.
// content not restricted either, just some bytes. no need to parse it,
// generic representation should be just fine.
//
// #[RRClass(ANY)]
// pub struct NULL;

// text representation like: `WKS 127.0.0.1 TCP smtp http 110`. would
// have to parse protocol and service names.
//
// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(IN)]
// pub struct WKS {
//     pub address: Ipv4Addr,
//     pub protocol: u8,
//     pub bitmap: ..., // remaining bytes
// }

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct PTR {
	pub ptrdname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct HINFO {
	pub cpu: ShortText,
	pub os: ShortText,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct MINFO {
	pub rmailbx: DnsCompressedName,
	pub emailbx: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct MX {
	pub preference: u16,
	pub mxname: DnsCompressedName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct TXT {
	pub text: LongText,
}

// end of RFC 1035: no DnsCompressedName below!

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct RP {
	pub mbox: DnsCanonicalName,
	pub txt: DnsCanonicalName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct AFSDB {
	pub subtype: u16,
	pub hostname: DnsCanonicalName,
}

// https://tools.ietf.org/html/rfc1183#section-3.1 says "its format in
// master files is a <character-string>" which say nothing about the
// binary encoding; later it says "<PSDN-address> is a string of decimal
// digits", so it would seem that there is no length encoding or
// restriction.
//
// wireshark and bind use <character-string> though (bind also wants at
// least 4 bytes in the field: probably due to "beginning with the 4
// digit DNIC").
//
// #[RRClass(ANY)]
// pub struct X25 {
//     pub psdn_address: ShortText,
// }

// #[RRClass(ANY)]
// pub struct ISDN {
//     pub isdn_address: ShortText,
//     pub subaddress: Option<ShortText>,
// }

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct RT {
	pub preference: u16,
	pub intermediate: DnsCanonicalName,
}

// #[RRClass(ANY)]
// pub struct NSAP;

#[allow(non_camel_case_types)]
#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRTypeName = "NSAP-PTR"]
#[RRClass(ANY)]
pub struct NSAP_PTR {
	pub owner: DnsCanonicalName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct SIG {
	pub rr_type: Type,
	pub algorithm: DnsSecAlgorithm,
	pub labels: u8,
	// RFC says this can be omitted in text form if it is the same as
	// the TTL on the SIG record. not supported to be omitted here
	// (TODO?).
	pub original_ttl: OptionalTTL,
	pub signature_expiration: TimeStrict,
	pub signature_inception: TimeStrict,
	pub key_tag: u16,
	pub signers_name: DnsCanonicalName,
	pub signature: Base64RemainingBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct KEY {
	pub flags: u16,
	pub protocol: DnskeyProtocol,
	pub algorithm: DnsSecAlgorithm,
	pub public_key: Base64RemainingBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(IN)]
pub struct PX {
	pub preference: u16,
	pub map822: DnsCanonicalName,
	pub mapx400: DnsCanonicalName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)] // not restricted in rfc 1712
pub struct GPOS {
	pub longitude: ShortText,
	pub latitude: ShortText,
	pub altitude: ShortText,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(IN)]
pub struct AAAA {
	pub addr: Ipv6Addr,
}

pub use super::weird_structs::LOC;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct NXT {
	pub next: DnsCanonicalName,
	pub types: NxtTypeBitmap,
}

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct EID;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct NIMLOC;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(IN)]
pub struct SRV {
	pub preference: u16,
	pub weight: u16,
	pub port: u16,
	pub target: DnsCanonicalName,
}

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct ATMA;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct NAPTR {
	pub order: u16,
	pub preference: u16,
	pub flags: ShortText,
	pub service: ShortText,
	pub regexp: ShortText,
	pub replacement: DnsCanonicalName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(IN)]
pub struct KX {
	pub preference: u16,
	pub exchanger: DnsCanonicalName,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
pub struct CERT {
	// https://www.iana.org/assignments/cert-rr-types/cert-rr-types.xhtml
	pub cert_type: u16,
	pub key_tag: u16,
	pub algorithm: DnsSecAlgorithm,
	pub certificate: Base64RemainingBlob,
}

pub use super::weird_structs::A6;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct DNAME {
	pub target: DnsCanonicalName,
}

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct SINK;

// OPT should be decoded at "transport level", abuses ttl and class
// fields too.
// pub struct OPT;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct APL;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct DS {
	pub key_tag: u16,
	pub algorithm: DnsSecAlgorithm,
	pub digest_type: DnsSecDigestAlgorithm,
	pub digest: HexRemainingBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
pub struct SSHFP {
	pub algorithm: SshFpAlgorithm,
	pub fingerprint_type: SshFpType,
	// RFC 4255 doesn't specify whether whitespace is allowed.
	// `HexRemainingBlob` allows whitespace.
	pub fingerprint: HexRemainingBlob,
}

pub use super::weird_structs::IPSECKEY;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct RRSIG {
	pub rr_type: Type,
	pub algorithm: DnsSecAlgorithm,
	pub labels: u8,
	pub original_ttl: u32,
	pub signature_expiration: Time,
	pub signature_inception: Time,
	pub key_tag: u16,
	pub signers_name: DnsCanonicalName,
	pub signature: Base64RemainingBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct NSEC {
	pub next: DnsName, // RFC 6840 says not canonic (updates RFC 4034)
	pub types: NsecTypeBitmap,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct DNSKEY {
	pub flags: DnskeyFlags,
	pub protocol: DnskeyProtocol, // should always be DNSSEC (3) according to RFC 4034
	pub algorithm: DnsSecAlgorithm,
	pub public_key: Base64RemainingBlob,
}

impl DNSKEY {
	fn alg1_tag(&self) -> u16 {
		let key: &[u8] = &self.public_key;
		if key.is_empty() { return 0; } // not enough data
		let pkey;
		if 0 == key[0] {
			// two-byte length encoding of exponent
			if key.len() < 3 { return 0; } // not enough data
			let explen = ((key[1] as u16) << 8) + (key[2] as u16);
			if explen < 256 { return 0; } // should have used shorter length encoding
			if key.len() < 3 + (explen as usize) { return 0; } // not enough data
			pkey = &key[3 + (explen as usize)..];
		} else {
			// one-byte length encoding of exponent
			let explen = key[0];
			if key.len() < 1 + (explen as usize) { return 0; } // not enough data
			pkey = &key[1 + (explen as usize)..];
		}
		if pkey.len() < 3 { return 0; } // not enough data
		((pkey[pkey.len() - 3] as u16) << 8) + (pkey[pkey.len() - 3] as u16)
	}

	/// calculate key tag
	pub fn tag(&self) -> u16 {
		if self.algorithm == DnsSecAlgorithm::RSAMD5 { return self.alg1_tag(); }

		let mut sum = 0u32;

		sum += self.flags.0 as u32;
		sum += (self.protocol.0 as u32) << 8;
		sum += self.algorithm.0 as u32;

		let key: &[u8] = &self.public_key;
		for i in 0..key.len() {
			let v = key[i] as u32;
			let v = if 0 == i & 1 { v << 8 } else { v };
			sum = sum.wrapping_add(v);
		}

		sum.wrapping_add(sum >> 16) as u16
	}

	#[cfg(feature = "crypto")]
	pub fn build_ds(&self, zone: &DnsName, algs: &[DnsSecDigestAlgorithmKnown]) -> Result<Vec<DS>> {
		if algs.is_empty() { return Ok(Vec::new()); }

		use crate::ser::packet::DnsPacketWriteContext;
		let mut ctx = DnsPacketWriteContext::new();
		ctx.enable_canonical();
		let mut bin = Vec::new();
		zone.serialize(&mut ctx, &mut bin)?;
		self.serialize(&mut ctx, &mut bin)?;

		let key_tag = self.tag();

		Ok(algs.iter().map(|alg| DS {
			key_tag,
			algorithm: self.algorithm,
			digest_type: (*alg).into(),
			digest: HexRemainingBlob::new(crate::crypto::ds_hash(*alg, &bin)),
		}).collect())
	}
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(IN)]
pub struct DHCID {
	pub content: Base64RemainingBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct NSEC3 {
	pub hash_algorithm: Nsec3Algorithm,
	pub flags: Nsec3Flags,
	pub iterations: u16,
	pub salt: HexShortBlob,
	pub next_hashed: NextHashedOwnerName,
	pub types: NsecTypeBitmap,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct NSEC3PARAM {
	pub hash_algorithm: Nsec3Algorithm,
	pub flags: Nsec3ParamFlags,
	pub iterations: u16,
	pub salt: HexShortBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct TLSA {
	// TODO: support acronyms from https://tools.ietf.org/html/rfc7218
	pub cert_usage: u8,
	pub selector: u8,
	pub matching_type: u8,
	pub data: HexRemainingBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct SMIMEA {
	// TODO: support acronyms from https://tools.ietf.org/html/rfc7218
	pub cert_usage: u8,
	pub selector: u8,
	pub matching_type: u8,
	pub data: HexRemainingBlob,
}

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct HIP;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct NINFO {
	pub text: LongText,
}


#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct RKEY {
	pub flags: u16,
	pub protocol: u8,
	pub algorithm: DnsSecAlgorithm,
	pub public_key: Base64RemainingBlob,
}

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct TALINK;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct CDS {
	pub key_tag: u16,
	pub algorithm: DnsSecAlgorithm,
	pub digest_type: DnsSecDigestAlgorithm,
	pub digest: HexRemainingBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct CDNSKEY {
	pub flags: DnskeyFlags,
	pub protocol: DnskeyProtocol,
	pub algorithm: DnsSecAlgorithm,
	pub public_key: Base64RemainingBlob,
}

impl CDNSKEY {
	pub fn tag(&self) -> u16 {
		DNSKEY {
			flags: self.flags,
			protocol: self.protocol,
			algorithm: self.algorithm,
			public_key: self.public_key.clone(),
		}.tag()
	}
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct OPENPGPKEY {
	pub public_key: Base64RemainingBlob,
}

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct CSYNC;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(ANY)]
// pub struct ZONEMD {
// 	pub serial: u32,
// 	pub digest_type: u8,
// 	pub reserved: u8,
// 	pub digest: HexRemainingBlobNotEmpty,
// }

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
pub struct SPF {
	pub text: LongText,
}

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct UINFO;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct UID;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct GID;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct UNSPEC;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct NID;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct L32;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct L64;

// #[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
// pub struct LP;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct EUI48 {
	pub addr: EUI48Addr,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct EUI64 {
	pub addr: EUI64Addr
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct TKEY {
	pub algorithm: DnsName,
	pub inception: u32,
	pub expiration: u32,
	pub mode: u16,
	pub error: u16,
	pub key: Base64LongBlob,
	pub other: Base64LongBlob,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct TSIG {
	pub algorithm: DnsName,
	pub signed: Time48,
	pub fudge: u16,
	pub mac: Base64LongBlob,
	pub original_id: u16,
	pub error: u16,
	pub other: Base64LongBlob,
}

// QTYPEs: IXFR, AXFR, MAILB, MAILA, ANY

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct URI {
	pub priority: u16,
	pub weight: u16,
	pub target: UriText,
}

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
// #[RRClass(?)]
pub struct CAA {
	pub flags: CaaFlags,
	pub tag: UnquotedShortText,
	pub value: RemainingText,
}

// pub struct AVC;
// pub struct DOA;
// pub struct AMTRELAY;
// pub struct TA;

#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(ANY)]
pub struct DLV {
	pub key_tag: u16,
	pub algorithm: DnsSecAlgorithm,
	pub digest_type: DnsSecDigestAlgorithm,
	pub digest: HexRemainingBlob,
}

// powerdns
#[derive(Clone, PartialEq, Eq, Debug, DnsPacketData, DnsTextData, RRData)]
#[RRClass(IN)] // used to lookup A and AAAA - only useful in IN
pub struct ALIAS {
	pub content: DnsName,
}