use std::collections::HashMap;
use std::fmt;
use std::str::{FromStr, Lines};

use crate::errors::{HandlingError, RequestError};

const HTTP_VERSION: &'static str = "HTTP/1.1";

#[derive(Debug)]
pub struct Request {
	pub method: Method,
	pub uri: String,
	pub headers: Vec<(String, String)>,
	pub body: Option<Vec<u8>>,
}

#[derive(Debug)]
pub struct Response {
	pub status: Status,
	pub headers: Vec<(String, String)>,
	pub body: String, // make into Option<Vec<u8>>
}

#[derive(Debug, Clone, Copy)]
pub enum Status {
	Ok = 200,
	SeeOther = 303,
	NotFound = 404,
	BadRequest = 400,
	Unauthorized = 401,
	InternalServerError = 500,
}

#[derive(Debug)]
pub enum Method {
	Get,
	Post,
	Delete,
}

impl FromStr for Method {
	type Err = RequestError;
	fn from_str(s: &str) -> Result<Self, Self::Err> {
		match s {
			"GET" => Ok(Self::Get),
			"POST" => Ok(Self::Post),
			"DELETE" => Ok(Self::Delete),
			_ => Err(Self::Err::UnusedMethod),
		}
	}
}

impl Status {
	pub fn message(&self) -> &'static str {
		match self {
			Self::Ok => "OK",
			Self::NotFound => "NOT FOUND",
			Self::BadRequest => "BAD REQUEST",
			Self::Unauthorized => "UNAUTHORIZED",
			Self::InternalServerError => "INTERNAL SERVER ERROR",
			Self::SeeOther => "SEE OTHER",
		}
	}
}

//impl Request {
//	pub fn form(&self) -> Result<HashMap<&str, String>, RequestError> {
//		let mut hashmap = HashMap::new();
//		dbg!(&self.body);
//		for mut x in self.body.split("&").map(|x| x.split("=")) {
//			hashmap.insert(
//				x.next().ok_or(RequestError::NotAForm)?,
//				decode(x.next().ok_or(RequestError::NotAForm)?)?.into_owned().replace("+", " "),
//			);
//		}
//		Ok(hashmap)
//	}
//}

impl Request {
	pub fn add_body(&mut self, body: Vec<u8>) {
		self.body = Some(body);
	}
}

impl TryFrom<Vec<String>> for Request {
	type Error = RequestError;

	fn try_from(s: Vec<String>) -> Result<Self, Self::Error> {
		//dbg!(&s);
		let mut iter = s.iter();
		let mut first = iter
			.next()
			.ok_or(RequestError::BadRequest)?
			.split_whitespace();
		let method: Method = first.next().ok_or(RequestError::BadRequest)?.parse()?;
		let uri = first.next().ok_or(RequestError::BadRequest)?.to_string();
		let mut headers: Vec<(String, String)> = vec![];

		for line in iter {
			let mut line = line.split(":").take(2);
			let left = line.next().ok_or(RequestError::BadRequest)?.trim();
			let right = line.next().ok_or(RequestError::BadRequest)?.trim();
			headers.push((left.to_string(), right.to_string()));
		}

		Ok(Self {
			method,
			uri,
			headers,
			body: None,
		})
	}
}

impl Response {
	pub fn new(status: Status, headers: Vec<(&str, &str)>, body: String) -> Self {
		Self {
			status,
			headers: headers
				.into_iter()
				.map(|(x, y)| (x.to_owned(), y.to_owned()))
				.collect(),
			body,
		}
	}
}

impl fmt::Display for Response {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
		let headers: String = self
			.headers
			.iter()
			.map(|x| format!("{}:{}\n", x.0, x.1))
			.fold(String::from(""), |a, b| format!("{}{}", a, b)); // possibly slow

		write!(
			f,
			"{} {} {}\n{}\n\n{}",
			HTTP_VERSION,
			self.status as i32,
			self.status.message(),
			headers,
			self.body,
		)
	}
}