nom 0.0.1

#[macro_use]
extern crate nom;

use nom::{IResult,Producer,FileProducer,ProducerState,FlatMapper,Mapper,Mapper2,line_ending,not_line_ending, space, alphanumeric, is_alphanumeric, multispace};
use nom::IResult::*;

use std::str;
use std::collections::HashMap;
use std::fmt::Show;


fn empty_result(i:&[u8]) -> IResult<&[u8], ()> { Done(i,()) }
tag!(semicolon ";".as_bytes());
o!(comment_body<&[u8],&[u8]> semicolon ~ [ not_line_ending]);
o!(comment<&[u8], ()> comment_body ~ line_ending ~ [ empty_result ]);
opt!(opt_comment<&[u8],&[u8]> comment_body);

tag!(lsb "[".as_bytes());
tag!(rsb "]".as_bytes());
fn category_name(input:&[u8]) -> IResult<&[u8], &str> {
  for idx in range(0, input.len()) {
    if input[idx] == ']' as u8 {
      return Done(input.slice_from(idx), input.slice(0, idx)).map_res(str::from_utf8)
    }
  }
  Done("".as_bytes(), input).map_res(str::from_utf8)
}
o!(category<&[u8], &str> lsb ~ [ category_name ] ~ rsb ~ opt_multispace);

tag!(equal "=".as_bytes());
fn not_equal(input:&[u8]) -> IResult<&[u8], &[u8]> {
  for idx in range(0, input.len()) {
    if input[idx] == '=' as u8 {
      return Done(input.slice_from(idx), input.slice(0, idx))
    }
  }
  Done("".as_bytes(), input)
}

fn value_parser(input:&[u8]) -> IResult<&[u8], &str> {
  for idx in range(0, input.len()) {
    if input[idx] == '\n' as u8 || input[idx] == ';' as u8 {
      return Done(input.slice_from(idx), input.slice(0, idx)).map_res(str::from_utf8)
    }
  }
  Done("".as_bytes(), input).map_res(str::from_utf8)
}

fn parameter_parser(input: &[u8]) -> IResult<&[u8], &str> {
  alphanumeric(input).map_res(str::from_utf8)
}

opt!(opt_multispace<&[u8],&[u8]> multispace);
o!(value<&[u8],&str> space ~ equal ~ space ~ [ value_parser ] ~ space ~ opt_comment ~ opt_multispace);
chain!(key_value<&[u8],(&str,&str)>, |:|{(key, val)},  key: parameter_parser, val: value,);

fn keys_and_values<'a>(input: &'a[u8], mut z: HashMap<&'a str, &'a str>) -> IResult<&'a[u8], HashMap<&'a str, &'a str> > {
  fold0_impl!(<&[u8], HashMap<&str, &str> >, |: mut h:HashMap<&'a str, &'a str>, (k, v)| {
    h.insert(k,v);
    h
  }, key_value, input, z);
}

fn keys_and_values_wrapper<'a>(input:&'a[u8]) -> IResult<&'a[u8], HashMap<&'a str, &'a str> > {
  let h: HashMap<&str, &str> = HashMap::new();
  let res = keys_and_values(input, h);
  //println!("{:?}", res);
  res
}

chain!(category_and_keys<&[u8],(&str,HashMap<&str,&str>)>,move |:|{(category, keys)},  category: category, keys: keys_and_values_wrapper,);

fn categories<'a>(input: &'a[u8]) -> IResult<&'a[u8], HashMap<&'a str, HashMap<&'a str, &'a str> > > {
  let mut z: HashMap<&str, HashMap<&str, &str>> = HashMap::new();
  fold0_impl!(<&[u8], HashMap<&str, HashMap<&str, &str> > >, |: mut h:HashMap<&'a str, HashMap<&'a str, &'a str> >, (k, v)| {
    h.insert(k,v);
    h
  }, category_and_keys, input, z);
}

#[test]
fn parse_comment_test() {
  let ini_file = ";comment
[category]
parameter=value
key = value2

[other]
number = 1234
str = a b cc dd ; comment";

  let ini_without_comment = "[category]
parameter=value
key = value2

[other]
number = 1234
str = a b cc dd ; comment";

  let res = Done((), ini_file.as_bytes()).flat_map(comment);
  println!("{:?}", res);
  match res {
    IResult::Done(i, o) => println!("i: {:?} | o: {:?}", str::from_utf8(i), o),
    _ => println!("error")
  }

  assert_eq!(res, Done(ini_without_comment.as_bytes(), ()));
}

#[test]
fn parse_category_test() {
  let ini_file = "[category]

parameter=value
key = value2";

  let ini_without_category = "parameter=value
key = value2";

  let res = Done((), ini_file.as_bytes()).flat_map(category);
  println!("{:?}", res);
  match res {
    IResult::Done(i, o) => println!("i: {:?} | o: {:?}", str::from_utf8(i), o),
    _ => println!("error")
  }

  assert_eq!(res, Done(ini_without_category.as_bytes(), "category"));
}

#[test]
fn parse_key_value_test() {
  let ini_file = "parameter=value
key = value2";

  let ini_without_key_value = "key = value2";

  let res = Done((), ini_file.as_bytes()).flat_map(key_value);
  println!("{:?}", res);
  match res {
    IResult::Done(i, (o1, o2)) => println!("i: {:?} | o: ({:?},{:?})", str::from_utf8(i), o1, o2),
    _ => println!("error")
  }

  assert_eq!(res, Done(ini_without_key_value.as_bytes(), ("parameter", "value")));
}


#[test]
fn parse_key_value_with_space_test() {
  let ini_file = "parameter = value
key = value2";

  let ini_without_key_value = "key = value2";

  let res = Done((), ini_file.as_bytes()).flat_map(key_value);
  println!("{:?}", res);
  match res {
    IResult::Done(i, (o1, o2)) => println!("i: {:?} | o: ({:?},{:?})", str::from_utf8(i), o1, o2),
    _ => println!("error")
  }

  assert_eq!(res, Done(ini_without_key_value.as_bytes(), ("parameter", "value")));
}

#[test]
fn parse_key_value_with_comment_test() {
  let ini_file = "parameter=value;abc
key = value2";

  let ini_without_key_value = "key = value2";

  let res = Done((), ini_file.as_bytes()).flat_map(key_value);
  println!("{:?}", res);
  match res {
    IResult::Done(i, (o1, o2)) => println!("i: {:?} | o: ({:?},{:?})", str::from_utf8(i), o1, o2),
    _ => println!("error")
  }

  assert_eq!(res, Done(ini_without_key_value.as_bytes(), ("parameter", "value")));
}

#[test]
fn parse_multiple_keys_and_values_test() {
  let ini_file = "parameter=value;abc

key = value2

[category]";

  let ini_without_key_value = "[category]";

  let mut h: HashMap<&str, &str> = HashMap::new();
  let res = keys_and_values(ini_file.as_bytes(), h);
  println!("{:?}", res);
  match res {
    IResult::Done(i, ref o) => println!("i: {:?} | o: {:?}", str::from_utf8(i), o),
    _ => println!("error")
  }

  let mut expected: HashMap<&str, &str> = HashMap::new();
  expected.insert("parameter", "value");
  expected.insert("key", "value2");
  assert_eq!(res, Done(ini_without_key_value.as_bytes(), expected));
}

#[test]
fn parse_category_then_multiple_keys_and_values_test() {
  //FIXME: there can be an empty line or a comment line after a category
  let ini_file = "[abcd]
parameter=value;abc

key = value2

[category]";

  let ini_after_parser = "[category]";

  let res = category_and_keys(ini_file.as_bytes());
  println!("{:?}", res);
  match res {
    IResult::Done(i, ref o) => println!("i: {:?} | o: {:?}", str::from_utf8(i), o),
    _ => println!("error")
  }

  let mut expected_h: HashMap<&str, &str> = HashMap::new();
  expected_h.insert("parameter", "value");
  expected_h.insert("key", "value2");
  assert_eq!(res, Done(ini_after_parser.as_bytes(), ("abcd", expected_h)));
}

#[test]
fn parse_multiple_categories_test() {
  let ini_file = "[abcd]

parameter=value;abc

key = value2

[category]
parameter3=value3
key4 = value4
";

  let ini_after_parser = "";

  let res = categories(ini_file.as_bytes());
  println!("{:?}", res);
  match res {
    IResult::Done(i, ref o) => println!("i: {:?} | o: {:?}", str::from_utf8(i), o),
    _ => println!("error")
  }

  let mut expected_1: HashMap<&str, &str> = HashMap::new();
  expected_1.insert("parameter", "value");
  expected_1.insert("key", "value2");
  let mut expected_2: HashMap<&str, &str> = HashMap::new();
  expected_2.insert("parameter3", "value3");
  expected_2.insert("key4", "value4");
  let mut expected_h: HashMap<&str, HashMap<&str, &str>> = HashMap::new();
  expected_h.insert("abcd",     expected_1);
  expected_h.insert("category", expected_2);
  assert_eq!(res, Done(ini_after_parser.as_bytes(), expected_h));
}