use nom::bytes::complete::is_not;
use nom::bytes::complete::tag;
use nom::sequence::delimited;
use nom::IResult;
use serde::{Deserialize, Serialize};
use std::fmt;
use std::str;

#[derive(Clone, Debug, Default, Eq, Hash, PartialEq, Serialize, Deserialize)]
pub struct Regex {
	pub value: String,
}

impl<'a> From<&'a str> for Regex {
	fn from(r: &str) -> Regex {
		Regex {
			value: String::from(r),
		}
	}
}

impl fmt::Display for Regex {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		write!(f, "/{}/", &self.value)
	}
}

pub fn regex(i: &str) -> IResult<&str, Regex> {
	let (i, v) = delimited(tag("/"), is_not("/"), tag("/"))(i)?;
	Ok((i, Regex::from(v)))
}

#[cfg(test)]
mod tests {

	use super::*;

	#[test]
	fn regex_simple() {
		let sql = "/test/";
		let res = regex(sql);
		assert!(res.is_ok());
		let out = res.unwrap().1;
		assert_eq!("/test/", format!("{}", out));
		assert_eq!(out, Regex::from("test"));
	}

	#[test]
	fn regex_complex() {
		let sql = "/test.*/";
		let res = regex(sql);
		assert!(res.is_ok());
		let out = res.unwrap().1;
		assert_eq!("/test.*/", format!("{}", out));
		assert_eq!(out, Regex::from("test.*"));
	}
}