From f08648e4b5a9f7855a2ed9068a386e2f3c596322 Mon Sep 17 00:00:00 2001
From: Ruben Beltran del Rio <jj@r.bdr.sh>
Date: Tue, 16 Dec 2025 10:40:44 +0100
Subject: Initial implementation

---
 src/patterns.rs | 77 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 src/patterns.rs

(limited to 'src/patterns.rs')

diff --git a/src/patterns.rs b/src/patterns.rs
new file mode 100644
index 0000000..12c790a
--- /dev/null
+++ b/src/patterns.rs
@@ -0,0 +1,77 @@
+use crate::utils::parse_color;
+
+/// 8x8 1-bit pattern data
+/// 0 = foreground color, 1 = background color
+pub const STITCH: [u8; 64] = [
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1,
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1,
+];
+
+pub const SHINGLES: [u8; 64] = [
+    1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0,
+    0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1,
+];
+
+pub const SHADOW_GRID: [u8; 64] = [
+    1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0,
+    0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0,
+];
+
+pub const WICKER: [u8; 64] = [
+    0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0,
+    0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0,
+];
+
+/// Creates a cairo surface pattern from pattern data
+pub fn create_pattern(
+    pattern_data: &[u8; 64],
+    foreground: &str,
+    background: &str,
+) -> Result<cairo::SurfacePattern, cairo::Error> {
+    let surface = cairo::ImageSurface::create(cairo::Format::Rgb24, 8, 8)?;
+
+    {
+        let ctx = cairo::Context::new(&surface)?;
+        let fg = parse_color(foreground);
+        let bg = parse_color(background);
+
+        for y in 0..8 {
+            for x in 0..8 {
+                let value = pattern_data[y * 8 + x];
+                let (r, g, b) = if value == 0 { fg } else { bg };
+
+                ctx.set_source_rgb(r, g, b);
+                ctx.rectangle(x as f64, y as f64, 1.0, 1.0);
+                ctx.fill()?;
+            }
+        }
+    }
+
+    let pattern = cairo::SurfacePattern::create(&surface);
+    pattern.set_extend(cairo::Extend::Repeat);
+    Ok(pattern)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_pattern_data_lengths() {
+        assert_eq!(STITCH.len(), 64);
+        assert_eq!(SHINGLES.len(), 64);
+        assert_eq!(SHADOW_GRID.len(), 64);
+        assert_eq!(WICKER.len(), 64);
+    }
+
+    #[test]
+    fn test_pattern_values() {
+        // All pattern values should be 0 or 1
+        for &val in &STITCH {
+            assert!(val == 0 || val == 1);
+        }
+        for &val in &SHINGLES {
+            assert!(val == 0 || val == 1);
+        }
+    }
+}
-- 
cgit