mod errors;
mod tokens;

use std::collections::VecDeque;
use std::fs::File;
use std::path::Path;
use std::str::Chars;
use tokens::Token;
use crate::lexer::errors::LexerErrors;
use crate::lexer::errors::LexerErrors::EmptyTextSequenceError;

pub type Result<T> = std::result::Result<T, errors::LexerErrors>;

pub struct Lexer<'a> {
    input: String,
    chars: Chars<'a>,
}

impl Lexer<'_> {

    /// Create a new Lexer for the given String
    /// Example:
    /// ```
    /// use cb_calculator::lexer;
    /// let text = "some text";
    /// lexer::Lexer::new(String::from(text));
    /// ```
    #[inline]
    pub fn new(input: String) -> Lexer {
        Lexer { input, chars: input.chars() }
    }

    // Get the next token
    pub fn next(&mut self) -> Result<Option<Token>> {
        let mut buffer: Vec<char> = Vec::new();
        loop {
            if let Some(c) = self.chars.next() {
                buffer.push(c);
            }
        }
    }
}