//! Editor functionality
use crate::helpers::*;

use nix::sys::termios::Termios;
use nix::unistd::read;

use std::io;
use std::io::prelude::*;
use std::io::{BufReader, Error, Stdin};
use std::str::Chars;

/// Main structure for the editor
///
/// impl blocks are split similarly to the original C implementation
pub struct Editor {}

// init
impl Editor {
    pub fn new() -> Self {
        Editor {}
    }
}

// Terminal
impl Editor {
    fn read_key(&mut self) -> Option<Vec<char>> {
        let stdin = io::stdin();
        let stdin = stdin.lock();
        let mut in_str = String::new();
        let mut input = BufReader::with_capacity(3, stdin);
        input.read_to_string(&mut in_str).unwrap();

        let mut output: Vec<char> = vec![];

        for char in in_str.chars() {
            output.push(char);
        }

        if output.len() == 0 {
            return None;
        }

        return Some(output);
    }
}

// Input
impl Editor {
    pub fn process_keypress(&mut self) -> Option<()> {
        match self.read_key() {
            // Just continue the input loop on an "empty" keypress
            None => Some(()),
            Some(chars) => {
                let first = chars[0];

                if first == ctrl_key('q') {
                    // Break out of the input loop
                    return None;
                }

                print!("{:?}\r\n", chars);

                // Continue the main input loop
                Some(())
            }
        }
    }
}

// Output
impl Editor {
    pub fn refresh_screen() {
        let stdout = io::stdout();
        let mut handle = stdout.lock();

        let mut buffer = String::from("\x1b[2J").into_bytes();

        handle.write_all(&mut buffer).unwrap();
    }
}