pub struct Res {
  pub count: usize,
  pub added: bool,
  pub removed: bool,
  pub value: String,
}

#[derive(PartialEq, Debug)]
pub enum Mode {
  INIT,
  BOTH,
  LEFT,
  RIGHT,
}

fn get_line_res(s: &String, mode: Mode) -> Res {
  Res {
    count: s.split('\n').count(),
    added: if mode == Mode::RIGHT { true } else { false },
    removed: if mode == Mode::LEFT { true } else { false },
    value: s.clone(),
  }
}
fn get_res(s: &String, mode: Mode) -> Res {
  Res {
    count: s.chars().count(),
    added: if mode == Mode::RIGHT { true } else { false },
    removed: if mode == Mode::LEFT { true } else { false },
    value: s.clone(),
  }
}

pub fn diff_chars(s1: &str, s2: &str) -> Vec<Res> {
  let mut mode = Mode::INIT;
  let mut s: String = String::new();

  let mut result: Vec<Res> = Vec::new();

  for d in diff::chars(s1, s2) {
    match d {
      diff::Result::Left(l) => {
        if mode != Mode::LEFT && mode != Mode::INIT {
          result.push(get_res(&s, mode));
          s.clear();
        }
        mode = Mode::LEFT;
        s.push(l);
      }
      diff::Result::Right(r) => {
        if mode != Mode::RIGHT && mode != Mode::INIT {
          result.push(get_res(&s, mode));
          s.clear();
        }
        mode = Mode::RIGHT;
        s.push(r);
      }
      diff::Result::Both(l, _) => {
        if mode != Mode::BOTH && mode != Mode::INIT {
          result.push(get_res(&s, mode));
          s.clear();
        }
        mode = Mode::BOTH;
        s.push(l);
      }
    }
  }

  if s.len() > 0 {
    result.push(get_res(&s, mode));
    s.clear();
  }

  result
}

pub fn diff_lines(s1: &str, s2: &str) -> Vec<Res> {
  let mut result: Vec<Res> = Vec::new();
  let mut mode = Mode::INIT;
  let mut s: String = String::new();

  for d in diff::lines(s1, s2) {
    match d {
      diff::Result::Left(l) => {
        if mode != Mode::LEFT && mode != Mode::INIT {
          result.push(get_line_res(&s, mode));
          s.clear();
        }
        mode = Mode::LEFT;
        if s.len() > 0 {
          s.push('\n')
        }
        s.push_str(l);
      }
      diff::Result::Right(r) => {
        if mode != Mode::RIGHT && mode != Mode::INIT {
          result.push(get_line_res(&s, mode));
          s.clear();
        }
        mode = Mode::RIGHT;
        if s.len() > 0 {
          s.push('\n')
        }
        s.push_str(r);
      }
      diff::Result::Both(l, _) => {
        if mode != Mode::BOTH && mode != Mode::INIT {
          result.push(get_line_res(&s, mode));
          s.clear()
        }
        mode = Mode::BOTH;
        if s.len() > 0 {
          s.push('\n')
        }
        s.push_str(l);
      }
    }
  }

  if s.len() > 0 {
    result.push(get_line_res(&s, mode));
    s.clear();
  }

  result
}