// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

#[macro_escape];
#[doc(hidden)];

macro_rules! uint_module (($T:ty, $T_SIGNED:ty, $bits:expr) => (

pub static BITS : uint = $bits;
pub static BYTES : uint = ($bits / 8);

pub static MIN: $T = 0 as $T;
pub static MAX: $T = 0 as $T - 1 as $T;

impl CheckedDiv for $T {
    #[inline]
    fn checked_div(&self, v: &$T) -> Option<$T> {
        if *v == 0 {
            None
        } else {
            Some(self / *v)
        }
    }
}

impl Num for $T {}

#[cfg(not(test))]
impl Ord for $T {
    #[inline]
    fn lt(&self, other: &$T) -> bool { (*self) < (*other) }
}

#[cfg(not(test))]
impl Eq for $T {
    #[inline]
    fn eq(&self, other: &$T) -> bool { return (*self) == (*other); }
}

impl Orderable for $T {
    #[inline]
    fn min(&self, other: &$T) -> $T {
        if *self < *other { *self } else { *other }
    }

    #[inline]
    fn max(&self, other: &$T) -> $T {
        if *self > *other { *self } else { *other }
    }

    /// Returns the number constrained within the range `mn <= self <= mx`.
    #[inline]
    fn clamp(&self, mn: &$T, mx: &$T) -> $T {
        match () {
            _ if (*self > *mx) => *mx,
            _ if (*self < *mn) => *mn,
            _                  => *self,
        }
    }
}

impl Default for $T {
    #[inline]
    fn default() -> $T { 0 }
}

impl Zero for $T {
    #[inline]
    fn zero() -> $T { 0 }

    #[inline]
    fn is_zero(&self) -> bool { *self == 0 }
}

impl One for $T {
    #[inline]
    fn one() -> $T { 1 }
}

#[cfg(not(test))]
impl Add<$T,$T> for $T {
    #[inline]
    fn add(&self, other: &$T) -> $T { *self + *other }
}

#[cfg(not(test))]
impl Sub<$T,$T> for $T {
    #[inline]
    fn sub(&self, other: &$T) -> $T { *self - *other }
}

#[cfg(not(test))]
impl Mul<$T,$T> for $T {
    #[inline]
    fn mul(&self, other: &$T) -> $T { *self * *other }
}

#[cfg(not(test))]
impl Div<$T,$T> for $T {
    #[inline]
    fn div(&self, other: &$T) -> $T { *self / *other }
}

#[cfg(not(test))]
impl Rem<$T,$T> for $T {
    #[inline]
    fn rem(&self, other: &$T) -> $T { *self % *other }
}

#[cfg(not(test))]
impl Neg<$T> for $T {
    #[inline]
    fn neg(&self) -> $T { -*self }
}

impl Unsigned for $T {}

impl Integer for $T {
    /// Calculates `div` (`/`) and `rem` (`%`) simultaneously
    #[inline]
    fn div_rem(&self, other: &$T) -> ($T,$T) {
        (*self / *other, *self % *other)
    }

    /// Unsigned integer division. Returns the same result as `div` (`/`).
    #[inline]
    fn div_floor(&self, other: &$T) -> $T { *self / *other }

    /// Unsigned integer modulo operation. Returns the same result as `rem` (`%`).
    #[inline]
    fn mod_floor(&self, other: &$T) -> $T { *self % *other }

    /// Calculates `div_floor` and `mod_floor` simultaneously
    #[inline]
    fn div_mod_floor(&self, other: &$T) -> ($T,$T) {
        (*self / *other, *self % *other)
    }

    /// Calculates the Greatest Common Divisor (GCD) of the number and `other`
    #[inline]
    fn gcd(&self, other: &$T) -> $T {
        // Use Euclid's algorithm
        let mut m = *self;
        let mut n = *other;
        while m != 0 {
            let temp = m;
            m = n % temp;
            n = temp;
        }
        n
    }

    /// Calculates the Lowest Common Multiple (LCM) of the number and `other`
    #[inline]
    fn lcm(&self, other: &$T) -> $T {
        (*self * *other) / self.gcd(other)
    }

    /// Returns `true` if the number can be divided by `other` without leaving a remainder
    #[inline]
    fn is_multiple_of(&self, other: &$T) -> bool { *self % *other == 0 }

    /// Returns `true` if the number is divisible by `2`
    #[inline]
    fn is_even(&self) -> bool { self & 1 == 0 }

    /// Returns `true` if the number is not divisible by `2`
    #[inline]
    fn is_odd(&self) -> bool { !self.is_even() }
}

#[cfg(not(test))]
impl BitOr<$T,$T> for $T {
    #[inline]
    fn bitor(&self, other: &$T) -> $T { *self | *other }
}

#[cfg(not(test))]
impl BitAnd<$T,$T> for $T {
    #[inline]
    fn bitand(&self, other: &$T) -> $T { *self & *other }
}

#[cfg(not(test))]
impl BitXor<$T,$T> for $T {
    #[inline]
    fn bitxor(&self, other: &$T) -> $T { *self ^ *other }
}

#[cfg(not(test))]
impl Shl<$T,$T> for $T {
    #[inline]
    fn shl(&self, other: &$T) -> $T { *self << *other }
}

#[cfg(not(test))]
impl Shr<$T,$T> for $T {
    #[inline]
    fn shr(&self, other: &$T) -> $T { *self >> *other }
}

#[cfg(not(test))]
impl Not<$T> for $T {
    #[inline]
    fn not(&self) -> $T { !*self }
}

impl Bounded for $T {
    #[inline]
    fn min_value() -> $T { MIN }

    #[inline]
    fn max_value() -> $T { MAX }
}

impl Int for $T {}

// String conversion functions and impl str -> num

/// Parse a byte slice as a number in the given base.
#[inline]
pub fn parse_bytes(buf: &[u8], radix: uint) -> Option<$T> {
    strconv::from_str_bytes_common(buf, radix, false, false, false,
                                   strconv::ExpNone, false, false)
}

impl FromStr for $T {
    #[inline]
    fn from_str(s: &str) -> Option<$T> {
        strconv::from_str_common(s, 10u, false, false, false,
                                 strconv::ExpNone, false, false)
    }
}

impl FromStrRadix for $T {
    #[inline]
    fn from_str_radix(s: &str, radix: uint) -> Option<$T> {
        strconv::from_str_common(s, radix, false, false, false,
                                 strconv::ExpNone, false, false)
    }
}

// String conversion functions and impl num -> str

/// Convert to a string as a byte slice in a given base.
#[inline]
pub fn to_str_bytes<U>(n: $T, radix: uint, f: |v: &[u8]| -> U) -> U {
    // The radix can be as low as 2, so we need at least 64 characters for a
    // base 2 number.
    let mut buf = [0u8, ..64];
    let mut cur = 0;
    strconv::int_to_str_bytes_common(n, radix, strconv::SignNone, |i| {
        buf[cur] = i;
        cur += 1;
    });
    f(buf.slice(0, cur))
}

impl ToStr for $T {
    /// Convert to a string in base 10.
    #[inline]
    fn to_str(&self) -> ~str {
        self.to_str_radix(10u)
    }
}

impl ToStrRadix for $T {
    /// Convert to a string in a given base.
    #[inline]
    fn to_str_radix(&self, radix: uint) -> ~str {
        let mut buf = ~[];
        strconv::int_to_str_bytes_common(*self, radix, strconv::SignNone, |i| {
            buf.push(i);
        });
        // We know we generated valid utf-8, so we don't need to go through that
        // check.
        unsafe { str::raw::from_utf8_owned(buf) }
    }
}

impl Primitive for $T {}

impl Bitwise for $T {
    /// Counts the number of bits set. Wraps LLVM's `ctpop` intrinsic.
    #[inline]
    fn population_count(&self) -> $T {
        (*self as $T_SIGNED).population_count() as $T
    }

    /// Counts the number of leading zeros. Wraps LLVM's `ctlz` intrinsic.
    #[inline]
    fn leading_zeros(&self) -> $T {
        (*self as $T_SIGNED).leading_zeros() as $T
    }

    /// Counts the number of trailing zeros. Wraps LLVM's `cttz` intrinsic.
    #[inline]
    fn trailing_zeros(&self) -> $T {
        (*self as $T_SIGNED).trailing_zeros() as $T
    }
}

#[cfg(test)]
mod tests {
    use prelude::*;
    use super::*;

    use num;
    use num::CheckedDiv;
    use num::Bitwise;
    use mem;
    use u16;

    #[test]
    fn test_num() {
        num::test_num(10 as $T, 2 as $T);
    }

    #[test]
    fn test_orderable() {
        assert_eq!((1 as $T).min(&(2 as $T)), 1 as $T);
        assert_eq!((2 as $T).min(&(1 as $T)), 1 as $T);
        assert_eq!((1 as $T).max(&(2 as $T)), 2 as $T);
        assert_eq!((2 as $T).max(&(1 as $T)), 2 as $T);
        assert_eq!((1 as $T).clamp(&(2 as $T), &(4 as $T)), 2 as $T);
        assert_eq!((8 as $T).clamp(&(2 as $T), &(4 as $T)), 4 as $T);
        assert_eq!((3 as $T).clamp(&(2 as $T), &(4 as $T)), 3 as $T);
    }

    #[test]
    fn test_div_mod_floor() {
        assert_eq!((10 as $T).div_floor(&(3 as $T)), 3 as $T);
        assert_eq!((10 as $T).mod_floor(&(3 as $T)), 1 as $T);
        assert_eq!((10 as $T).div_mod_floor(&(3 as $T)), (3 as $T, 1 as $T));
        assert_eq!((5 as $T).div_floor(&(5 as $T)), 1 as $T);
        assert_eq!((5 as $T).mod_floor(&(5 as $T)), 0 as $T);
        assert_eq!((5 as $T).div_mod_floor(&(5 as $T)), (1 as $T, 0 as $T));
        assert_eq!((3 as $T).div_floor(&(7 as $T)), 0 as $T);
        assert_eq!((3 as $T).mod_floor(&(7 as $T)), 3 as $T);
        assert_eq!((3 as $T).div_mod_floor(&(7 as $T)), (0 as $T, 3 as $T));
    }

    #[test]
    fn test_gcd() {
        assert_eq!((10 as $T).gcd(&2), 2 as $T);
        assert_eq!((10 as $T).gcd(&3), 1 as $T);
        assert_eq!((0 as $T).gcd(&3), 3 as $T);
        assert_eq!((3 as $T).gcd(&3), 3 as $T);
        assert_eq!((56 as $T).gcd(&42), 14 as $T);
    }

    #[test]
    fn test_lcm() {
        assert_eq!((1 as $T).lcm(&0), 0 as $T);
        assert_eq!((0 as $T).lcm(&1), 0 as $T);
        assert_eq!((1 as $T).lcm(&1), 1 as $T);
        assert_eq!((8 as $T).lcm(&9), 72 as $T);
        assert_eq!((11 as $T).lcm(&5), 55 as $T);
        assert_eq!((99 as $T).lcm(&17), 1683 as $T);
    }

    #[test]
    fn test_multiple_of() {
        assert!((6 as $T).is_multiple_of(&(6 as $T)));
        assert!((6 as $T).is_multiple_of(&(3 as $T)));
        assert!((6 as $T).is_multiple_of(&(1 as $T)));
    }

    #[test]
    fn test_even() {
        assert_eq!((0 as $T).is_even(), true);
        assert_eq!((1 as $T).is_even(), false);
        assert_eq!((2 as $T).is_even(), true);
        assert_eq!((3 as $T).is_even(), false);
        assert_eq!((4 as $T).is_even(), true);
    }

    #[test]
    fn test_odd() {
        assert_eq!((0 as $T).is_odd(), false);
        assert_eq!((1 as $T).is_odd(), true);
        assert_eq!((2 as $T).is_odd(), false);
        assert_eq!((3 as $T).is_odd(), true);
        assert_eq!((4 as $T).is_odd(), false);
    }

    #[test]
    fn test_bitwise() {
        assert_eq!(0b1110 as $T, (0b1100 as $T).bitor(&(0b1010 as $T)));
        assert_eq!(0b1000 as $T, (0b1100 as $T).bitand(&(0b1010 as $T)));
        assert_eq!(0b0110 as $T, (0b1100 as $T).bitxor(&(0b1010 as $T)));
        assert_eq!(0b1110 as $T, (0b0111 as $T).shl(&(1 as $T)));
        assert_eq!(0b0111 as $T, (0b1110 as $T).shr(&(1 as $T)));
        assert_eq!(MAX - (0b1011 as $T), (0b1011 as $T).not());
    }

    #[test]
    fn test_bitcount() {
        assert_eq!((0b010101 as $T).population_count(), 3);
    }

    #[test]
    pub fn test_to_str() {
        assert_eq!((0 as $T).to_str_radix(10u), ~"0");
        assert_eq!((1 as $T).to_str_radix(10u), ~"1");
        assert_eq!((2 as $T).to_str_radix(10u), ~"2");
        assert_eq!((11 as $T).to_str_radix(10u), ~"11");
        assert_eq!((11 as $T).to_str_radix(16u), ~"b");
        assert_eq!((255 as $T).to_str_radix(16u), ~"ff");
        assert_eq!((0xff as $T).to_str_radix(10u), ~"255");
    }

    #[test]
    pub fn test_from_str() {
        assert_eq!(from_str::<$T>("0"), Some(0u as $T));
        assert_eq!(from_str::<$T>("3"), Some(3u as $T));
        assert_eq!(from_str::<$T>("10"), Some(10u as $T));
        assert_eq!(from_str::<u32>("123456789"), Some(123456789 as u32));
        assert_eq!(from_str::<$T>("00100"), Some(100u as $T));

        assert!(from_str::<$T>("").is_none());
        assert!(from_str::<$T>(" ").is_none());
        assert!(from_str::<$T>("x").is_none());
    }

    #[test]
    pub fn test_parse_bytes() {
        use str::StrSlice;
        assert_eq!(parse_bytes("123".as_bytes(), 10u), Some(123u as $T));
        assert_eq!(parse_bytes("1001".as_bytes(), 2u), Some(9u as $T));
        assert_eq!(parse_bytes("123".as_bytes(), 8u), Some(83u as $T));
        assert_eq!(u16::parse_bytes("123".as_bytes(), 16u), Some(291u as u16));
        assert_eq!(u16::parse_bytes("ffff".as_bytes(), 16u), Some(65535u as u16));
        assert_eq!(parse_bytes("z".as_bytes(), 36u), Some(35u as $T));

        assert!(parse_bytes("Z".as_bytes(), 10u).is_none());
        assert!(parse_bytes("_".as_bytes(), 2u).is_none());
    }

    #[test]
    fn test_uint_to_str_overflow() {
        let mut u8_val: u8 = 255_u8;
        assert_eq!(u8_val.to_str(), ~"255");

        u8_val += 1 as u8;
        assert_eq!(u8_val.to_str(), ~"0");

        let mut u16_val: u16 = 65_535_u16;
        assert_eq!(u16_val.to_str(), ~"65535");

        u16_val += 1 as u16;
        assert_eq!(u16_val.to_str(), ~"0");

        let mut u32_val: u32 = 4_294_967_295_u32;
        assert_eq!(u32_val.to_str(), ~"4294967295");

        u32_val += 1 as u32;
        assert_eq!(u32_val.to_str(), ~"0");

        let mut u64_val: u64 = 18_446_744_073_709_551_615_u64;
        assert_eq!(u64_val.to_str(), ~"18446744073709551615");

        u64_val += 1 as u64;
        assert_eq!(u64_val.to_str(), ~"0");
    }

    #[test]
    fn test_uint_from_str_overflow() {
        let mut u8_val: u8 = 255_u8;
        assert_eq!(from_str::<u8>("255"), Some(u8_val));
        assert!(from_str::<u8>("256").is_none());

        u8_val += 1 as u8;
        assert_eq!(from_str::<u8>("0"), Some(u8_val));
        assert!(from_str::<u8>("-1").is_none());

        let mut u16_val: u16 = 65_535_u16;
        assert_eq!(from_str::<u16>("65535"), Some(u16_val));
        assert!(from_str::<u16>("65536").is_none());

        u16_val += 1 as u16;
        assert_eq!(from_str::<u16>("0"), Some(u16_val));
        assert!(from_str::<u16>("-1").is_none());

        let mut u32_val: u32 = 4_294_967_295_u32;
        assert_eq!(from_str::<u32>("4294967295"), Some(u32_val));
        assert!(from_str::<u32>("4294967296").is_none());

        u32_val += 1 as u32;
        assert_eq!(from_str::<u32>("0"), Some(u32_val));
        assert!(from_str::<u32>("-1").is_none());

        let mut u64_val: u64 = 18_446_744_073_709_551_615_u64;
        assert_eq!(from_str::<u64>("18446744073709551615"), Some(u64_val));
        assert!(from_str::<u64>("18446744073709551616").is_none());

        u64_val += 1 as u64;
        assert_eq!(from_str::<u64>("0"), Some(u64_val));
        assert!(from_str::<u64>("-1").is_none());
    }

    #[test]
    #[should_fail]
    pub fn to_str_radix1() {
        100u.to_str_radix(1u);
    }

    #[test]
    #[should_fail]
    pub fn to_str_radix37() {
        100u.to_str_radix(37u);
    }

    #[test]
    fn test_unsigned_checked_div() {
        assert_eq!(10u.checked_div(&2), Some(5));
        assert_eq!(5u.checked_div(&0), None);
    }
}

))
