qr_code_styling/config/
color.rs

1//! Color representation for QR code styling.
2
3use crate::error::{QRError, Result};
4
5/// RGBA color representation.
6#[derive(Debug, Clone, Copy, PartialEq, Eq)]
7#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
8pub struct Color {
9    /// Red component (0-255).
10    pub r: u8,
11    /// Green component (0-255).
12    pub g: u8,
13    /// Blue component (0-255).
14    pub b: u8,
15    /// Alpha component (0-255).
16    pub a: u8,
17}
18
19impl Color {
20    /// Create a new color with full opacity.
21    pub const fn rgb(r: u8, g: u8, b: u8) -> Self {
22        Self { r, g, b, a: 255 }
23    }
24
25    /// Create a new color with specified alpha.
26    pub const fn rgba(r: u8, g: u8, b: u8, a: u8) -> Self {
27        Self { r, g, b, a }
28    }
29
30    /// Create a color from a hex string (e.g., "#FF0000" or "#FF0000FF").
31    pub fn from_hex(hex: &str) -> Result<Self> {
32        let hex = hex.trim_start_matches('#');
33
34        match hex.len() {
35            3 => {
36                // Short form: #RGB -> #RRGGBB
37                let r = u8::from_str_radix(&hex[0..1], 16)
38                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
39                let g = u8::from_str_radix(&hex[1..2], 16)
40                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
41                let b = u8::from_str_radix(&hex[2..3], 16)
42                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
43                Ok(Self::rgb(r * 17, g * 17, b * 17))
44            }
45            6 => {
46                // Standard form: #RRGGBB
47                let r = u8::from_str_radix(&hex[0..2], 16)
48                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
49                let g = u8::from_str_radix(&hex[2..4], 16)
50                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
51                let b = u8::from_str_radix(&hex[4..6], 16)
52                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
53                Ok(Self::rgb(r, g, b))
54            }
55            8 => {
56                // With alpha: #RRGGBBAA
57                let r = u8::from_str_radix(&hex[0..2], 16)
58                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
59                let g = u8::from_str_radix(&hex[2..4], 16)
60                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
61                let b = u8::from_str_radix(&hex[4..6], 16)
62                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
63                let a = u8::from_str_radix(&hex[6..8], 16)
64                    .map_err(|_| QRError::InvalidColor(hex.to_string()))?;
65                Ok(Self::rgba(r, g, b, a))
66            }
67            _ => Err(QRError::InvalidColor(hex.to_string())),
68        }
69    }
70
71    /// Convert to hex string (e.g., "#FF0000").
72    pub fn to_hex(&self) -> String {
73        if self.a == 255 {
74            format!("#{:02X}{:02X}{:02X}", self.r, self.g, self.b)
75        } else {
76            format!("#{:02X}{:02X}{:02X}{:02X}", self.r, self.g, self.b, self.a)
77        }
78    }
79
80    /// Convert to CSS rgba string.
81    pub fn to_rgba_string(&self) -> String {
82        if self.a == 255 {
83            format!("rgb({}, {}, {})", self.r, self.g, self.b)
84        } else {
85            format!(
86                "rgba({}, {}, {}, {:.3})",
87                self.r,
88                self.g,
89                self.b,
90                self.a as f64 / 255.0
91            )
92        }
93    }
94
95    /// Black color.
96    pub const BLACK: Color = Color::rgb(0, 0, 0);
97
98    /// White color.
99    pub const WHITE: Color = Color::rgb(255, 255, 255);
100
101    /// Transparent color.
102    pub const TRANSPARENT: Color = Color::rgba(0, 0, 0, 0);
103}
104
105impl Default for Color {
106    fn default() -> Self {
107        Self::BLACK
108    }
109}
110
111impl std::fmt::Display for Color {
112    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
113        write!(f, "{}", self.to_hex())
114    }
115}
116
117#[cfg(test)]
118mod tests {
119    use super::*;
120
121    #[test]
122    fn test_from_hex() {
123        assert_eq!(Color::from_hex("#FF0000").unwrap(), Color::rgb(255, 0, 0));
124        assert_eq!(Color::from_hex("#00FF00").unwrap(), Color::rgb(0, 255, 0));
125        assert_eq!(Color::from_hex("#0000FF").unwrap(), Color::rgb(0, 0, 255));
126        assert_eq!(Color::from_hex("000000").unwrap(), Color::rgb(0, 0, 0));
127        assert_eq!(Color::from_hex("#FFF").unwrap(), Color::rgb(255, 255, 255));
128    }
129
130    #[test]
131    fn test_to_hex() {
132        assert_eq!(Color::rgb(255, 0, 0).to_hex(), "#FF0000");
133        assert_eq!(Color::rgba(255, 0, 0, 128).to_hex(), "#FF000080");
134    }
135}
qr_code_styling/config/color.rs

qr_code_styling/config/
color.rs
