//! ASCII base on RFC20.
//!
//! // 基于 ASCII 规范文档 RFC20 编写的库
//!
//! This crate is very simple, just ord() and chr()
//!
//! // 这个库非常简单易用，因为只有 ord() 和 chr() 这两个方法
//!
//! # ord()
//! &str to Some(i32), "s" -> Some(115)
//!
//! Example:
//!
//!     let asc = Asciis{};
//!     let r = asc.ord("s");
//!     assert_eq!(r, Some(115));
//!
//! # chr()
//! i32 to Some(String), 97 -> Some("a")
//!
//! Example:
//!
//!     let asc = Asciis{};
//!     let v = asc.chr(97);
//!     assert_eq!(v, Some("a"));
//!
//! # FAQ
//! Q:Why the type of return value is Option, not i32 or String?
//!
//! // 为什么返回值的类型是 Option ，而不是 i32 或者 String ？
//!
//! A: The ascii value range is [0~127], which can cause panic! if exceeded. So Option better than i32 or String.
//!
//! // ASCII 码的范围是 [0~127]，超出范围就会引发 panic!。所以 Option 比 i32 或者 String 更合适。
//!
//! Q: Rust std has AsciiExt,why write this crate?
//!
//! // Rust 标准库 std 中已经有了 AsciiExt，为什么你还要写这个库？
//!
//! A: Python's simple style influenced me. ord() and chr() are very simple to use.
//!
//! // Python 简约的风格影响着我，我觉得 ord() 和 chr() 这种方式更好用。
//! Q: Where does the standard code come from?
//!
//! // 这些标准代码从哪里来？
//!
//! A: From the RFC20 https://tools.ietf.org/html/rfc20#section-2
//!
//! // 详见 RFC20 文档的第 2 部分介绍 https://tools.ietf.org/html/rfc20#section-2
//!
//! Q: How do I determine what value the ord () method should pass in?
//!
//! // 我如何确定 ord() 方法应该传入什么值？
//!
//! A：See https://tools.ietf.org/html/rfc20#section-2
//!
//! // 跟上面一样，详见 RFC20 文档的第 2 部分介绍，这是 ASCII 规范中约定的值
// --snip--


mod asciis {
    use std::collections::HashMap;
    pub struct Asciis{}
    impl Asciis{
        fn init (&self) -> HashMap<String, i32>{
            let contrast: HashMap<String, i32> = [
                (String::from("SOH"), 1),
                (String::from("SOX"), 2),
                (String::from("ETX"), 3),
                (String::from("EOT"), 4),
                (String::from("ENQ"), 5),
                (String::from("ACK"), 6),
                (String::from("BEL"), 7),
                (String::from("BS"), 8),
                (String::from("HT"), 9),
                (String::from("LF"), 10),
                (String::from("VT"), 11),
                (String::from("FF"), 12),
                (String::from("CR"), 13),
                (String::from("SI"), 14),
                (String::from("SO"), 15),
                (String::from("DLE"), 16),
                (String::from("DC1"), 17),
                (String::from("DC2"), 18),
                (String::from("DC3"), 19),
                (String::from("DC4"), 20),
                (String::from("NAK"), 21),
                (String::from("SYN"), 22),
                (String::from("ETB"), 23),
                (String::from("CAN"), 24),
                (String::from("EM"), 25),
                (String::from("SUB"), 26),
                (String::from("ESC"), 27),
                (String::from("FS"), 28),
                (String::from("GS"), 29),
                (String::from("RS"), 30),
                (String::from("US"), 31),
                (String::from("DEL"), 127),
                (String::from(" "), 32), // SP
                (String::from("!"), 33),
                (String::from("\""), 34),
                (String::from("#"), 35),
                (String::from("$"), 36),
                (String::from("%"), 37),
                (String::from("&"), 38),
                (String::from("'"), 39),
                (String::from("("), 40),
                (String::from(")"), 41),
                (String::from("*"), 42),
                (String::from("+"), 43),
                (String::from(","), 44),
                (String::from("-"), 45),
                (String::from("."), 46),
                (String::from("/"), 47),
                (String::from("0"), 48),
                (String::from("1"), 49),
                (String::from("2"), 50),
                (String::from("3"), 51),
                (String::from("4"), 52),
                (String::from("5"), 53),
                (String::from("6"), 54),
                (String::from("7"), 55),
                (String::from("8"), 56),
                (String::from("9"), 57),
                (String::from(":"), 58),
                (String::from(";"), 59),
                (String::from("<"), 60),
                (String::from("="), 61),
                (String::from(">"), 62),
                (String::from("?"), 63),
                (String::from("@"), 64),
                (String::from("A"), 65),
                (String::from("B"), 66),
                (String::from("C"), 67),
                (String::from("D"), 68),
                (String::from("E"), 69),
                (String::from("F"), 70),
                (String::from("G"), 71),
                (String::from("H"), 72),
                (String::from("I"), 73),
                (String::from("J"), 74),
                (String::from("K"), 75),
                (String::from("L"), 76),
                (String::from("M"), 77),
                (String::from("N"), 78),
                (String::from("O"), 79),
                (String::from("P"), 80),
                (String::from("Q"), 81),
                (String::from("R"), 82),
                (String::from("S"), 83),
                (String::from("T"), 84),
                (String::from("U"), 85),
                (String::from("V"), 86),
                (String::from("W"), 87),
                (String::from("X"), 88),
                (String::from("Y"), 89),
                (String::from("Z"), 90),
                (String::from("["), 91),
                (String::from(r"\"), 92),
                (String::from("]"), 93),
                (String::from("^"), 94),
                (String::from("_"), 95),
                (String::from("`"), 96),
                (String::from("a"), 97),
                (String::from("b"), 98),
                (String::from("c"), 99),
                (String::from("d"), 100),
                (String::from("e"), 101),
                (String::from("f"), 102),
                (String::from("g"), 103),
                (String::from("h"), 104),
                (String::from("i"), 105),
                (String::from("j"), 106),
                (String::from("k"), 107),
                (String::from("l"), 108),
                (String::from("m"), 109),
                (String::from("n"), 110),
                (String::from("o"), 111),
                (String::from("p"), 112),
                (String::from("q"), 113),
                (String::from("r"), 114),
                (String::from("s"), 115),
                (String::from("t"), 116),
                (String::from("u"), 117),
                (String::from("v"), 118),
                (String::from("w"), 119),
                (String::from("x"), 120),
                (String::from("y"), 121),
                (String::from("z"), 122),
                (String::from("{"), 123),
                (String::from("|"), 124),
                (String::from("}"), 125),
                (String::from("~"), 126),
            ].iter().cloned().collect();
            contrast
        }

        pub fn ord(&self, value: &str) -> Option<i32>{
            let hmp = self.init();
            let res = hmp.get(value);
            match res{
                Some(n) => Some(*res.unwrap()),
                None => None
            }
        }

        pub fn chr(&self, value: i32) -> Option<String>{
            let hmp = self.init();
            for (key, val) in hmp.iter().enumerate(){
                if value == *val.1{
                    return Some(val.0.to_string());
                    break;
                }
            }
            None
        }
    }

}