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

use crate::Stream;

/// List of possible [`ViewBox`] parsing errors.
#[derive(Clone, Copy, Debug)]
pub enum ViewBoxError {
    /// One of the numbers is invalid.
    InvalidNumber,

    /// ViewBox has a negative or zero size.
    InvalidSize,
}

impl std::fmt::Display for ViewBoxError {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        match *self {
            ViewBoxError::InvalidNumber => {
                write!(f, "viewBox contains an invalid number")
            }
            ViewBoxError::InvalidSize => {
                write!(f, "viewBox has a negative or zero size")
            }
        }
    }
}

impl std::error::Error for ViewBoxError {
    fn description(&self) -> &str {
        "a viewBox parsing error"
    }
}

/// Representation of the [`<viewBox>`] type.
///
/// [`<viewBox>`]: https://www.w3.org/TR/SVG2/coords.html#ViewBoxAttribute
#[allow(missing_docs)]
#[derive(Clone, Copy, PartialEq, Debug)]
pub struct ViewBox {
    pub x: f64,
    pub y: f64,
    pub w: f64,
    pub h: f64,
}

impl quote::ToTokens for ViewBox {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        let Self { x, y, w, h } = self;

        quote::quote! {
            svgrtypes::ViewBox {
                x: #x,
                y: #y,
                w: #w,
                h: #h,
            }
        }
        .to_tokens(tokens)
    }
}

impl ViewBox {
    /// Creates a new `ViewBox`.
    pub fn new(x: f64, y: f64, w: f64, h: f64) -> Self {
        ViewBox { x, y, w, h }
    }
}

impl std::str::FromStr for ViewBox {
    type Err = ViewBoxError;

    fn from_str(text: &str) -> Result<Self, ViewBoxError> {
        let mut s = Stream::from(text);

        let x = s
            .parse_list_number()
            .map_err(|_| ViewBoxError::InvalidNumber)?;
        let y = s
            .parse_list_number()
            .map_err(|_| ViewBoxError::InvalidNumber)?;
        let w = s
            .parse_list_number()
            .map_err(|_| ViewBoxError::InvalidNumber)?;
        let h = s
            .parse_list_number()
            .map_err(|_| ViewBoxError::InvalidNumber)?;

        if w <= 0.0 || h <= 0.0 {
            return Err(ViewBoxError::InvalidSize);
        }

        Ok(ViewBox::new(x, y, w, h))
    }
}

#[rustfmt::skip]
#[cfg(test)]
mod tests {
    use super::*;
    use std::str::FromStr;

    macro_rules! test {
        ($name:ident, $text:expr, $result:expr) => (
            #[test]
            fn $name() {
                let v = ViewBox::from_str($text).unwrap();
                assert_eq!(v, $result);
            }
        )
    }

    test!(parse_1, "-20 30 100 500", ViewBox::new(-20.0, 30.0, 100.0, 500.0));

    macro_rules! test_err {
        ($name:ident, $text:expr, $result:expr) => (
            #[test]
            fn $name() {
                assert_eq!(ViewBox::from_str($text).unwrap_err().to_string(), $result);
            }
        )
    }

    test_err!(parse_err_1, "qwe", "viewBox contains an invalid number");
    test_err!(parse_err_2, "10 20 30 0", "viewBox has a negative or zero size");
    test_err!(parse_err_3, "10 20 0 40", "viewBox has a negative or zero size");
    test_err!(parse_err_4, "10 20 0 0", "viewBox has a negative or zero size");
    test_err!(parse_err_5, "10 20 -30 0", "viewBox has a negative or zero size");
    test_err!(parse_err_6, "10 20 30 -40", "viewBox has a negative or zero size");
    test_err!(parse_err_7, "10 20 -30 -40", "viewBox has a negative or zero size");
}