#[cfg(feature="serialize")]
use serde::{Serialize, Serializer, Deserialize, Deserializer};

#[cfg(feature="serialize")]
use ethereum_types_serialize;

construct_uint!(U128, 2);
construct_uint!(U256, 4);
construct_uint!(U512, 8);

impl U256 {
	/// Multiplies two 256-bit integers to produce full 512-bit integer
	/// No overflow possible
	#[cfg(all(asm_available, target_arch="x86_64"))]
	pub fn full_mul(self, other: U256) -> U512 {
		let self_t: &[u64; 4] = &self.0;
		let other_t: &[u64; 4] = &other.0;
		let mut result: [u64; 8] = unsafe { ::core::mem::uninitialized() };
		unsafe {
			asm!("
				mov $8, %rax
				mulq $12
				mov %rax, $0
				mov %rdx, $1

				mov $8, %rax
				mulq $13
				add %rax, $1
				adc $$0, %rdx
				mov %rdx, $2

				mov $8, %rax
				mulq $14
				add %rax, $2
				adc $$0, %rdx
				mov %rdx, $3

				mov $8, %rax
				mulq $15
				add %rax, $3
				adc $$0, %rdx
				mov %rdx, $4

				mov $9, %rax
				mulq $12
				add %rax, $1
				adc %rdx, $2
				adc $$0, $3
				adc $$0, $4
				xor $5, $5
				adc $$0, $5
				xor $6, $6
				adc $$0, $6
				xor $7, $7
				adc $$0, $7

				mov $9, %rax
				mulq $13
				add %rax, $2
				adc %rdx, $3
				adc $$0, $4
				adc $$0, $5
				adc $$0, $6
				adc $$0, $7

				mov $9, %rax
				mulq $14
				add %rax, $3
				adc %rdx, $4
				adc $$0, $5
				adc $$0, $6
				adc $$0, $7

				mov $9, %rax
				mulq $15
				add %rax, $4
				adc %rdx, $5
				adc $$0, $6
				adc $$0, $7

				mov $10, %rax
				mulq $12
				add %rax, $2
				adc %rdx, $3
				adc $$0, $4
				adc $$0, $5
				adc $$0, $6
				adc $$0, $7

				mov $10, %rax
				mulq $13
				add %rax, $3
				adc %rdx, $4
				adc $$0, $5
				adc $$0, $6
				adc $$0, $7

				mov $10, %rax
				mulq $14
				add %rax, $4
				adc %rdx, $5
				adc $$0, $6
				adc $$0, $7

				mov $10, %rax
				mulq $15
				add %rax, $5
				adc %rdx, $6
				adc $$0, $7

				mov $11, %rax
				mulq $12
				add %rax, $3
				adc %rdx, $4
				adc $$0, $5
				adc $$0, $6
				adc $$0, $7

				mov $11, %rax
				mulq $13
				add %rax, $4
				adc %rdx, $5
				adc $$0, $6
				adc $$0, $7

				mov $11, %rax
				mulq $14
				add %rax, $5
				adc %rdx, $6
				adc $$0, $7

				mov $11, %rax
				mulq $15
				add %rax, $6
				adc %rdx, $7
				"
            : /* $0 */ "={r8}"(result[0]), /* $1 */ "={r9}"(result[1]), /* $2 */ "={r10}"(result[2]),
			  /* $3 */ "={r11}"(result[3]), /* $4 */ "={r12}"(result[4]), /* $5 */ "={r13}"(result[5]),
			  /* $6 */ "={r14}"(result[6]), /* $7 */ "={r15}"(result[7])

            : /* $8 */ "m"(self_t[0]), /* $9 */ "m"(self_t[1]), /* $10 */  "m"(self_t[2]),
			  /* $11 */ "m"(self_t[3]), /* $12 */ "m"(other_t[0]), /* $13 */ "m"(other_t[1]),
			  /* $14 */ "m"(other_t[2]), /* $15 */ "m"(other_t[3])
			: "rax", "rdx"
			:
			);
		}
		U512(result)
	}

	/// Multiplies two 256-bit integers to produce full 512-bit integer
	/// No overflow possible
	#[inline(always)]
	#[cfg(not(all(asm_available, target_arch="x86_64")))]
	pub fn full_mul(self, other: U256) -> U512 {
		U512(uint_full_mul_reg!(U256, 4, self, other))
	}
}

impl From<U256> for U512 {
	fn from(value: U256) -> U512 {
		let U256(ref arr) = value;
		let mut ret = [0; 8];
		ret[0] = arr[0];
		ret[1] = arr[1];
		ret[2] = arr[2];
		ret[3] = arr[3];
		U512(ret)
	}
}

impl From<U512> for U256 {
	fn from(value: U512) -> U256 {
		let U512(ref arr) = value;
		if arr[4] | arr[5] | arr[6] | arr[7] != 0 {
			panic!("Overflow");
		}
		let mut ret = [0; 4];
		ret[0] = arr[0];
		ret[1] = arr[1];
		ret[2] = arr[2];
		ret[3] = arr[3];
		U256(ret)
	}
}

impl<'a> From<&'a U256> for U512 {
	fn from(value: &'a U256) -> U512 {
		let U256(ref arr) = *value;
		let mut ret = [0; 8];
		ret[0] = arr[0];
		ret[1] = arr[1];
		ret[2] = arr[2];
		ret[3] = arr[3];
		U512(ret)
	}
}

impl<'a> From<&'a U512> for U256 {
	fn from(value: &'a U512) -> U256 {
		let U512(ref arr) = *value;
		if arr[4] | arr[5] | arr[6] | arr[7] != 0 {
			panic!("Overflow");
		}
		let mut ret = [0; 4];
		ret[0] = arr[0];
		ret[1] = arr[1];
		ret[2] = arr[2];
		ret[3] = arr[3];
		U256(ret)
	}
}

impl From<U256> for U128 {
	fn from(value: U256) -> U128 {
		let U256(ref arr) = value;
		if arr[2] | arr[3] != 0 {
			panic!("Overflow");
		}
		let mut ret = [0; 2];
		ret[0] = arr[0];
		ret[1] = arr[1];
		U128(ret)
	}
}

impl From<U512> for U128 {
	fn from(value: U512) -> U128 {
		let U512(ref arr) = value;
		if arr[2] | arr[3] | arr[4] | arr[5] | arr[6] | arr[7] != 0 {
			panic!("Overflow");
		}
		let mut ret = [0; 2];
		ret[0] = arr[0];
		ret[1] = arr[1];
		U128(ret)
	}
}

impl From<U128> for U512 {
	fn from(value: U128) -> U512 {
		let U128(ref arr) = value;
		let mut ret = [0; 8];
		ret[0] = arr[0];
		ret[1] = arr[1];
		U512(ret)
	}
}

impl From<U128> for U256 {
	fn from(value: U128) -> U256 {
		let U128(ref arr) = value;
		let mut ret = [0; 4];
		ret[0] = arr[0];
		ret[1] = arr[1];
		U256(ret)
	}
}

impl From<U256> for u64 {
	fn from(value: U256) -> u64 {
		value.as_u64()
	}
}

impl From<U256> for u32 {
	fn from(value: U256) -> u32 {
		value.as_u32()
	}
}

impl<'a> From<&'a [u8; 32]> for U256 {
	fn from(bytes: &[u8; 32]) -> Self {
		bytes[..].into()
	}
}

impl From<[u8; 32]> for U256 {
	fn from(bytes: [u8; 32]) -> Self {
		bytes[..].as_ref().into()
	}
}

impl From<U256> for [u8; 32] {
	fn from(number: U256) -> Self {
		let mut arr = [0u8; 32];
		number.to_big_endian(&mut arr);
		arr
	}
}

impl<'a> From<&'a [u8; 16]> for U128 {
	fn from(bytes: &[u8; 16]) -> Self {
		bytes[..].into()
	}
}

impl From<[u8; 16]> for U128 {
	fn from(bytes: [u8; 16]) -> Self {
		bytes[..].as_ref().into()
	}
}

impl From<U128> for [u8; 16] {
	fn from(number: U128) -> Self {
		let mut arr = [0u8; 16];
		number.to_big_endian(&mut arr);
		arr
	}
}

impl<'a> From<&'a [u8; 64]> for U512 {
	fn from(bytes: &[u8; 64]) -> Self {
		bytes[..].into()
	}
}

impl From<[u8; 64]> for U512 {
	fn from(bytes: [u8; 64]) -> Self {
		bytes[..].as_ref().into()
	}
}

impl From<U512> for [u8; 64] {
	fn from(number: U512) -> Self {
		let mut arr = [0u8; 64];
		number.to_big_endian(&mut arr);
		arr
	}
}

macro_rules! impl_serde {
	($name: ident, $len: expr) => {
		#[cfg(feature="serialize")]
		impl Serialize for $name {
			fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where S: Serializer {
				let mut slice = [0u8; 2 + 2 * $len * 8];
				let mut bytes = [0u8; $len * 8];
				self.to_big_endian(&mut bytes);
				ethereum_types_serialize::serialize_uint(&mut slice, &bytes, serializer)
			}
		}

		#[cfg(feature="serialize")]
		impl<'de> Deserialize<'de> for $name {
			fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where D: Deserializer<'de> {
				let mut bytes = [0u8; $len * 8];
				let wrote = ethereum_types_serialize::deserialize_check_len(deserializer, ethereum_types_serialize::ExpectedLen::Between(0, &mut bytes))?;
				Ok(bytes[0..wrote].into())
			}
		}
	}
}

impl_serde!(U128, 2);
impl_serde!(U256, 4);
impl_serde!(U512, 8);