tock 0.1.2

Digital clock for the terminal
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140

use std::fmt;
use std::str;
use std::cell;

/// Clear the screen.
pub const CLEAR: &'static str = "\x1B[2J";

/// Hide the cursor.
pub const HIDE: &'static str = "\x1B[?25l";

/// Show the cursor.
pub const SHOW: &'static str = "\x1B[?25h";

/// Reset the background color.
pub const RESET: Paint = Paint {
    color: Color::Reset,
    ground: Ground::Back,
};

/// Move the cursor to 0-indexed (x, y) terminal position.
#[derive(Copy, Clone, Debug, Default)]
pub struct Move(pub u16, pub u16);

impl fmt::Display for Move {
    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
        write!(fmt, "\x1B[{};{}H", self.1 + 1, self.0 + 1)
    }
}

/// Edge-triggered paint: will only write
/// escape code when switching paint colors.
#[derive(Clone, Debug)]
pub struct Brush {
    paint: Paint,
    dried: cell::Cell<bool>,
    on: bool,
}

impl Brush {
    pub fn new(color: Color) -> Self {
        Brush {
            paint: Paint { color, ground: Ground::Back },
            dried: cell::Cell::new(true),
            on: false,
        }
    }

    pub fn dip(&mut self, color: Color) {
        let old = self.paint;
        let new = Paint { color, ground: Ground::Back };
        if self.on { self.dried.set(old == new && self.dried.get()); }
        self.paint = new;
    }

    pub fn raise(&mut self) {
        self.set(false)
    }

    pub fn set(&mut self, on: bool) {
        self.dried.set(on == self.on && self.dried.get());
        self.on = on;
    }
}

impl fmt::Display for Brush {
    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
        if self.dried.get()  {
            return Ok(())
        }
        self.dried.set(true);
        write!(fmt, "{}", if self.on { self.paint } else { RESET })
    }
}

/// Change the terminal's writing color.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub struct Paint {
    pub color: Color,
    pub ground: Ground,
}

impl fmt::Display for Paint {
    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
        let g = self.ground as u8;
        match self.color {
        | Color::C8(c) => write!(fmt, "\x1B[{};5;{}m", g, c.0),
        | Color::C24(c) => write!(fmt, "\x1B[{};2;{};{};{}m", g, c.r, c.g, c.b),
        | Color::Reset => write!(fmt, "\x1B[{}m", g + 1),
        }
    }
}

#[repr(u8)]
#[allow(dead_code)]
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum Ground {
    Fore = 38,
    Back = 48,
}

#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum Color {
    C8(C8),
    C24(C24),
    Reset,
}

impl str::FromStr for Color {
    type Err = String;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        if let Ok(c) = s.parse::<u8>() {
            return Ok(Color::C8(C8(c)))
        }

        let mut it = s.split(',');

        let (r, g, b) = match (it.next(), it.next(), it.next(), it.next()) {
        | (Some(r), Some(g), Some(b), None) => (r, g, b),
        | _ => return Err(format!("[USER ERROR]: invalid color specifier {}", s))
        };

        match (r.parse::<u8>(), g.parse::<u8>(), b.parse::<u8>()) {
        | (Ok(r), Ok(g), Ok(b)) => Ok(Color::C24(C24 { r, g, b })),
        | _ => return Err(format!("[USER ERROR]: invalid color specifier {}", s))
        }
    }
}

/// 8-bit ANSI color.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub struct C8(pub u8);

/// 24-bit RGB color.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub struct C24 {
    pub r: u8,
    pub g: u8,
    pub b: u8,
}