nom 0.0.2

extern crate collections;

use std::fmt::Debug;
use internal::*;
use internal::IResult::*;

#[macro_export]
macro_rules! tag(
  ($name:ident $inp:expr) => (
    fn $name(i:&[u8]) -> IResult<&[u8], &[u8]>{
      if i.len() >= $inp.len() && i.slice(0, $inp.len()) == $inp {
        Done(i.slice_from($inp.len()), i.slice(0, $inp.len()))
      } else {
        Error(0)
      }
    }
  )
);

#[macro_export]
macro_rules! o(
  ($name:ident<$i:ty,$o:ty> $f1:ident ~ $($rest:tt)*) => (
    #[allow(unused_variables)]
    fn $name(input:$i) -> IResult<$i, $o>{
      match $f1(input) {
        IResult::Error(e)      => IResult::Error(e),
        IResult::Incomplete(i) => IResult::Incomplete(i),
        IResult::Done(i,o)     => {
          o_parser!(i ~ o ~ $($rest)*)
        }
      }
    }
  );
);

#[macro_export]
macro_rules! o_parser(
  ($i:ident ~ $o:ident ~ [ $e:ident ] ~ $s:ident) => (
    match $e($i) {
      IResult::Error(e)      => IResult::Error(e),
      IResult::Incomplete(i) => IResult::Incomplete(i),
      IResult::Done(i,o)     => {
        match $s(i) {
          IResult::Error(e)      => IResult::Error(e),
          IResult::Incomplete(i) => IResult::Incomplete(i),
          IResult::Done(i2,o2)     => {
            IResult::Done(i2, o)
          }
        }
      }
    }
  );

  ($i:ident ~ $o:ident ~ [ $e:ident ] ~ $($rest:tt)*) => (
    match $e($i) {
      IResult::Error(e)      => IResult::Error(e),
      IResult::Incomplete(i) => IResult::Incomplete(i),
      IResult::Done(i,o)     => {
        o_parser!(i ~ o ~ $($rest)*)
      }
    }
  );

  ($i:ident ~ $o:ident ~ [ $e:ident ]) => (
    $e($i)
  );

  ($i:ident ~ $o:ident ~ $e:ident ~ $($rest:tt)*) => (
    match $e($i) {
      IResult::Error(e)      => IResult::Error(e),
      IResult::Incomplete(i) => IResult::Incomplete(i),
      IResult::Done(i,_)     => {
        o_parser!(i ~ $o ~ $($rest)*)
      }
    }
  );

  ($i:ident ~ $o:ident ~ $e:ident) => (
    match $e($i) {
      IResult::Error(e)      => IResult::Error(e),
      IResult::Incomplete(i) => IResult::Incomplete(i),
      IResult::Done(i,_)     => {
        IResult::Done(i, $o)
      }
    }
  );

  ($i:ident ~ $o:ident) => (Done($i,$o));

);

#[macro_export]
macro_rules! chain (
  ($name:ident<$i:ty,$o:ty>, $assemble:expr, $($rest:tt)*) => (
    fn $name(i:$i) -> IResult<$i,$o>{
      chaining_parser!(i, $assemble, $($rest)*)
    }
  );
);

#[macro_export]
macro_rules! chaining_parser (
  ($i:expr, $assemble:expr, $field:ident : $e:expr, $($rest:tt)*) => (
    match $e($i) {
      IResult::Error(e)      => IResult::Error(e),
      IResult::Incomplete(i) => IResult::Incomplete(i),
      IResult::Done(i,o)     => {
        let $field = o;
        chaining_parser!(i, $assemble, $($rest)*)
      }
    }
  );

  ($i:expr, $assemble:expr, ) => (
    IResult::Done($i, $assemble())
  )
);

#[macro_export]
macro_rules! alt (
  ($name:ident<$i:ty,$o:ty>, $($rest:tt)*) => (
    fn $name(i:$i) -> IResult<$i,$o>{
      alt_parser!(i | $($rest)*)
    }
  );
);

#[macro_export]
macro_rules! alt_parser (
  ($i:ident | $e:ident | $($rest:tt)*) => (
    match $e($i) {
      IResult::Error(_)      => alt_parser!($i | $($rest)*),
      IResult::Incomplete(_) => alt_parser!($i | $($rest)*),
      IResult::Done(i,o)     => IResult::Done(i,o)
    }
  );

  ($i:ident | $e:ident) => (
    match $e($i) {
      IResult::Error(_)      => alt_parser!($i),
      IResult::Incomplete(_) => alt_parser!($i),
      IResult::Done(i,o)     => IResult::Done(i,o)
    }
  );

  ($i:ident) => (
    IResult::Error(1)
  )
);

pub fn print<'a,T: Debug>(input: T) -> IResult<T, ()> {
  println!("{:?}", input);
  Done(input, ())
}

pub fn begin<'a>(input: &'a [u8]) -> IResult<(), &'a [u8]> {
  Done((), input)
}

#[macro_export]
macro_rules! is_not(
  ($name:ident $arr:expr) => (
    fn $name(input:&[u8]) -> IResult<&[u8], &[u8]> {
      for idx in range(0, input.len()) {
        for &i in $arr.iter() {
          if input[idx] == i {
            return IResult::Done(input.slice_from(idx), input.slice(0, idx))
          }
        }
      }
      IResult::Done("".as_bytes(), input)
    }
  )
);

#[macro_export]
macro_rules! is_a(
  ($name:ident $arr:expr) => (
    fn $name(input:&[u8]) -> IResult<&[u8], &[u8]> {
      for idx in range(0, input.len()) {
        var res = false
        for &i in $arr.iter() {
          if input[idx] == i {
            res = true
          }
        }
        if !res {
          return IResult::Done(input.slice_from(idx), input.slice(0, idx))
        }
      }
      IResult::Done("".as_bytes(), input)
    }
  )
);

#[macro_export]
macro_rules! filter(
  ($name:ident $f:ident) => (
    fn $name(input:&[u8]) -> IResult<&[u8], &[u8]> {
      for idx in range(0, input.len()) {
        if !$f(input[idx]) {
          return IResult::Done(input.slice_from(idx), input.slice(0, idx))
        }
      }
      IResult::Done("".as_bytes(), input)
    }
  )
);

// FIXME: when rust-lang/rust#17436 is fixed, macros will be able to export
// public methods
//pub is_not!(line_ending "\r\n".as_bytes())
pub fn not_line_ending(input:&[u8]) -> IResult<&[u8], &[u8]> {
  for idx in range(0, input.len()) {
    for &i in "\r\n".as_bytes().iter() {
      if input[idx] == i {
        return Done(input.slice_from(idx), input.slice(0, idx))
      }
    }
  }
  Done("".as_bytes(), input)
}

tag!(tag_ln "\n".as_bytes());

pub fn line_ending(input:&[u8]) -> IResult<&[u8], &[u8]> {
  tag_ln(input)
}

pub fn is_alphabetic(chr:u8) -> bool {
  (chr >= 0x41 && chr <= 0x5A) || (chr >= 0x61 && chr <= 0x7A)
}

pub fn is_digit(chr: u8) -> bool {
  chr >= 0x30 && chr <= 0x39
}

pub fn is_alphanumeric(chr: u8) -> bool {
  is_alphabetic(chr) || is_digit(chr)
}

pub fn is_space(chr:u8) -> bool {
  chr == ' ' as u8 || chr == '\t' as u8
}

// FIXME: when rust-lang/rust#17436 is fixed, macros will be able to export
//pub filter!(alpha is_alphabetic)
//pub filter!(digit is_digit)
//pub filter!(alphanumeric is_alphanumeric)
pub fn alpha(input:&[u8]) -> IResult<&[u8], &[u8]> {
  for idx in range(0, input.len()) {
    if !is_alphabetic(input[idx]) {
      return Done(input.slice_from(idx), input.slice(0, idx))
    }
  }
  Done("".as_bytes(), input)
}

pub fn digit(input:&[u8]) -> IResult<&[u8], &[u8]> {
  for idx in range(0, input.len()) {
    if !is_digit(input[idx]) {
      return Done(input.slice_from(idx), input.slice(0, idx))
    }
  }
  Done("".as_bytes(), input)
}

pub fn alphanumeric(input:&[u8]) -> IResult<&[u8], &[u8]> {
  for idx in range(0, input.len()) {
    if !is_alphanumeric(input[idx]) {
      return Done(input.slice_from(idx), input.slice(0, idx))
    }
  }
  Done("".as_bytes(), input)
}

pub fn space(input:&[u8]) -> IResult<&[u8], &[u8]> {
  for idx in range(0, input.len()) {
    if !is_space(input[idx]) {
      return Done(input.slice_from(idx), input.slice(0, idx))
    }
  }
  Done("".as_bytes(), input)
}

pub fn multispace(input:&[u8]) -> IResult<&[u8], &[u8]> {
  for idx in range(0, input.len()) {
    if !is_space(input[idx]) && input[idx] != '\r' as u8 && input[idx] != '\n' as u8 {
      return Done(input.slice_from(idx), input.slice(0, idx))
    }
  }
  Done("".as_bytes(), input)
}

pub fn sized_buffer(input:&[u8]) -> IResult<&[u8], &[u8]> {
  if input.len() == 0 {
    return Incomplete(0)
  }

  let len = input[0] as usize;

  if input.len() >= len + 1 {
    return Done(input.slice_from(len+1), input.slice(1, len+1))
  } else {
    return Incomplete(0)
  }
}

#[macro_export]
macro_rules! opt(
  ($name:ident<$i:ty,$o:ty> $f:ident) => (
    fn $name(input:$i) -> IResult<$i, Option<$o>> {
      match $f(input) {
        IResult::Done(i,o) => IResult::Done(i, Some(o)),
        _                  => IResult::Done(input, None)
      }
    }
  )
);

// 0 or more
#[macro_export]
macro_rules! many0(
  ($name:ident<$i:ty,$o:ty> $f:ident) => (
    fn $name(input:$i) -> IResult<$i,Vec<$o>> {
      let mut begin = 0;
      let mut remaining = input.len();
      let mut res: Vec<$o> = Vec::new();
      loop {
        match $f(input.slice_from(begin)) {
          IResult::Done(i,o) => {
            res.push(o);
            begin += remaining - i.len();
            remaining = i.len();
            if begin >= input.len() {
              return IResult::Done(i, res)
            }
          },
          _                  => {
            return IResult::Done(input.slice_from(begin), res)
          }
        }
      }
    }
  )
);

// one or more
#[macro_export]
macro_rules! many1(
  ($name:ident<$i:ty,$o:ty> $f:ident) => (
    fn $name(input:$i) -> IResult<$i,Vec<$o>> {
      let mut begin = 0;
      let mut remaining = input.len();
      let mut res: Vec<$o> = Vec::new();
      loop {
        match $f(input.slice_from(begin)) {
          IResult::Done(i,o) => {
            res.push(o);
            begin += remaining - i.len();
            remaining = i.len();
            if begin >= input.len() {
              return IResult::Done(i, res)
            }
          },
          _                  => {
            if begin == 0 {
              return IResult::Error(0)
            } else {
              return IResult::Done(input.slice_from(begin), res)
            }
          }
        }
      }
    }
  )
);

#[macro_export]
macro_rules! fold0(
  ($name:ident<$i:ty,$o:ty>, $assemble:expr, $f:ident) => (
    fn $name(input:$i, z:$o) -> IResult<$i,$o> {
      fold0_impl!(<$i, $o>, $assemble, $f, input, z);
    }
  );
);

#[macro_export]
macro_rules! fold0_impl(
  (<$i:ty,$o:ty>, $assemble:expr, $f:ident, $input:ident, $z:ident) => (
    {
      let mut begin = 0;
      let mut remaining = $input.len();
      let mut res: $o = $z;
      loop {
        match $f($input.slice_from(begin)) {
          IResult::Done(i,o) => {
            //res.push(o);
            res = $assemble(res, o);
            begin += remaining - i.len();
            remaining = i.len();
            if begin >= $input.len() {
              return IResult::Done(i, res)
            }
          },
          _                  => {
            return IResult::Done($input.slice_from(begin), res)
          }
        }
      }
    }
  );
);

#[macro_export]
macro_rules! fold1(
  ($name:ident<$i:ty,$o:ty>, $assemble:expr, $f:ident) => (
    fn $name(input:$i, z:$o) -> IResult<$i,$o> {
      fold1_impl!(<$i, $o>, $assemble, $f, input, z);
    }
  );
);

#[macro_export]
macro_rules! fold1_impl(
  (<$i:ty,$o:ty>, $assemble:expr, $f:ident, $input:ident, $z:ident) => (
    {
      let mut begin = 0;
      let mut remaining = $input.len();
      let mut res: $o = $z;
      loop {
        match $f($input.slice_from(begin)) {
          IResult::Done(i,o) => {
            //res.push(o);
            res = $assemble(res, o);
            begin += remaining - i.len();
            remaining = i.len();
            if begin >= $input.len() {
              return IResult::Done(i, res)
            }
          },
          _                  => {
            if begin == 0 {
              return IResult::Error(0)
            } else {
              return IResult::Done($input.slice_from(begin), res)
            }
          }
        }
      }
    }
  );
);

pub fn length_value(input:&[u8]) -> IResult<&[u8], &[u8]> {
  let input_len = input.len();
  if input_len == 0 {
    return IResult::Error(0)
  }

  let len = input[0] as usize;
  if input_len - 1 >= len {
    return IResult::Done(input.slice_from(len+1), input.slice(1, len+1))
  } else {
    // FIXME: return Incomplete
    return IResult::Error(0)
  }
}

#[cfg(test)]
mod tests {
  use super::*;
  use map::*;
  use internal::IResult;
  use internal::IResult::*;

  #[test]
  fn character() {
    let empty = "".as_bytes();
    let a = "abcd".as_bytes();
    let b = "1234".as_bytes();
    let c = "a123".as_bytes();
    let d = "azé12".as_bytes();
    let e = " ".as_bytes();
    assert_eq!(Done((),a).flat_map(alpha), Done(empty, a));
    assert_eq!(Done((),b).flat_map(alpha), Done(b, empty));
    assert_eq!(Done((),c).flat_map(alpha), Done(c.slice_from(1), "a".as_bytes()));
    assert_eq!(Done((),d).flat_map(alpha), Done("é12".as_bytes(), "az".as_bytes()));
    assert_eq!(Done((),a).flat_map(digit), Done(a, empty));
    assert_eq!(Done((),b).flat_map(digit), Done(empty, b));
    assert_eq!(Done((),c).flat_map(digit), Done(c, empty));
    assert_eq!(Done((),d).flat_map(digit), Done(d, empty));
    assert_eq!(Done((),a).flat_map(alphanumeric), Done(empty, a));
    assert_eq!(Done((),b).flat_map(alphanumeric), Done(empty, b));
    assert_eq!(Done((),c).flat_map(alphanumeric), Done(empty, c));
    assert_eq!(Done((),d).flat_map(alphanumeric), Done("é12".as_bytes(), "az".as_bytes()));
    assert_eq!(Done((),e).flat_map(space), Done("".as_bytes(), " ".as_bytes()));
  }

  #[test]
  fn is_not() {
    let a = "ab12cd\nefgh".as_bytes();
    assert_eq!(Done((), a).flat_map(not_line_ending), Done("\nefgh".as_bytes(), "ab12cd".as_bytes()));

    let b = "ab12cd\nefgh\nijkl".as_bytes();
    assert_eq!(Done((), b).flat_map(not_line_ending), Done("\nefgh\nijkl".as_bytes(), "ab12cd".as_bytes()));
  }

  #[test]
  fn buffer_with_size() {
    let arr:[u8; 6us] = [3, 4, 5, 6, 7, 8];
    let res = Done((), arr.as_slice()).flat_map(sized_buffer);
    let i = [7,8];
    let o = [4,5,6];
    assert_eq!(res, Done(i.as_slice(), o.as_slice()))
  }

  #[test]
  fn t1() {
    let v1:Vec<u8> = vec![1,2,3];
    let v2:Vec<u8> = vec![4,5,6];
    let d = Done(v1.as_slice(), v2.as_slice());
    let res = d.flat_map(print);
    assert_eq!(res, Done(v2.as_slice(), ()));
  }

  #[derive(PartialEq,Eq,Debug)]
  struct B {
    a: u8,
    b: u8
  }

  #[test]
  fn chain_and_ignore() {
    tag!(x "abcd".as_bytes());
    tag!(y "efgh".as_bytes());
    fn ret_int(i:&[u8]) -> IResult<&[u8], u8> { Done(i,1) };
    //o!(z<&[u8], int>  x S x S retInt Z y);
    o!(z<&[u8], u8>  x ~ x ~ [ ret_int ] ~ y);

    let r = Done((), "abcdabcdefgh".as_bytes()).flat_map(z);
    assert_eq!(r, Done("".as_bytes(), 1));
  }


  #[test]
  fn chain() {
    tag!(x "abcd".as_bytes());
    fn temp_ret_int1(i:&[u8]) -> IResult<&[u8], u8> { Done(i,1) };
    o!(ret_int1<&[u8],u8> x ~ [ temp_ret_int1 ]);
    fn ret_int2(i:&[u8]) -> IResult<&[u8], u8> { Done(i,2) };
    chain!(f<&[u8],B>, |:|{B{a: aa, b: bb}}, aa: ret_int1, bb: ret_int2,);

    let r = Done((), "abcde".as_bytes()).flat_map(f);
    assert_eq!(r, Done("e".as_bytes(), B{a: 1, b: 2}));
  }

  #[test]
  fn alt() {
    fn work(input: &[u8]) -> IResult<&[u8],&[u8]> {
      Done("".as_bytes(), input)
    }

    #[allow(unused_variables)]
    fn dont_work(input: &[u8]) -> IResult<&[u8],&[u8]> {
      Error(3)
    }

    fn work2(input: &[u8]) -> IResult<&[u8],&[u8]> {
      Done(input, "".as_bytes())
    }

    alt!(alt1<&[u8],&[u8]>, dont_work | dont_work);
    alt!(alt2<&[u8],&[u8]>, dont_work | work);
    alt!(alt3<&[u8],&[u8]>, dont_work | dont_work | work2 | dont_work);

    let a = "abcd".as_bytes();
    assert_eq!(Done((), a).flat_map(alt1), Error(1));
    assert_eq!(Done((), a).flat_map(alt2), Done("".as_bytes(), a));
    assert_eq!(Done((), a).flat_map(alt3), Done(a, "".as_bytes()));
  }

  #[test]
  fn opt() {
    tag!(x "abcd".as_bytes());
    opt!(o<&[u8],&[u8]> x);

    let a = "abcdef".as_bytes();
    let b = "bcdefg".as_bytes();
    assert_eq!(Done((),a).flat_map(o), Done("ef".as_bytes(), Some("abcd".as_bytes())));
    assert_eq!(Done((),b).flat_map(o), Done("bcdefg".as_bytes(), None));
  }

  #[test]
  fn many0() {
    tag!(x "abcd".as_bytes());
    many0!(multi<&[u8],&[u8]> x);

    let a = "abcdef".as_bytes();
    let b = "abcdabcdef".as_bytes();
    let c = "azerty".as_bytes();

    let res1 = vec!["abcd".as_bytes()];
    assert_eq!(Done((),a).flat_map(multi), Done("ef".as_bytes(), res1));
    let res2 = vec!["abcd".as_bytes(), "abcd".as_bytes()];
    assert_eq!(Done((),b).flat_map(multi), Done("ef".as_bytes(), res2));
    assert_eq!(Done((),c).flat_map(multi), Done("azerty".as_bytes(), Vec::new()));
  }

  #[test]
  fn many1() {
    tag!(x "abcd".as_bytes());
    many1!(multi<&[u8],&[u8]> x);

    let a = "abcdef".as_bytes();
    let b = "abcdabcdef".as_bytes();
    let c = "azerty".as_bytes();
    let res1 = vec!["abcd".as_bytes()];
    assert_eq!(Done((),a).flat_map(multi), Done("ef".as_bytes(), res1));
    let res2 = vec!["abcd".as_bytes(), "abcd".as_bytes()];
    assert_eq!(Done((),b).flat_map(multi), Done("ef".as_bytes(), res2));
    assert_eq!(Done((),c).flat_map(multi), Error(0));
  }

  #[test]
  fn length_value_test() {
    let arr1:[u8; 6us] = [3, 4, 5, 6, 7, 8];
    let res1 = length_value(&arr1);
    let i1 = vec![7,8];
    let o1 = vec![4, 5, 6];
    assert_eq!(Done(i1.as_slice(), o1.as_slice()), res1);

    let arr2:[u8; 6us] = [0, 4, 5, 6, 7, 8];
    let res2 = length_value(&arr2);
    let i2:[u8; 5us] = [4,5,6,7,8];
    let o2 = "";
    assert_eq!(Done(i2.as_slice(), o2.as_bytes()), res2);

    let arr3:[u8; 7us] = [8, 4, 5, 6, 7, 8, 9];
    let res3 = length_value(&arr3);
    //FIXME: should be incomplete
    assert_eq!(Error(0), res3);
  }
}