From 9c8de5a1fa19dc0f6f48398fc3c7179d71156314 Mon Sep 17 00:00:00 2001
From: Tangent Wantwight <tangent128@gmail.com>
Date: Sun, 31 Oct 2021 19:20:10 -0400
Subject: [PATCH] Add 2021 Halloween pattern

---
 harrogate/Cargo.toml            |  1 +
 harrogate/src/halloween_2021.rs | 58 +++++++++++++++++++++++++++++++++
 harrogate/src/main.rs           |  4 +++
 3 files changed, 63 insertions(+)
 create mode 100644 harrogate/src/halloween_2021.rs

diff --git a/harrogate/Cargo.toml b/harrogate/Cargo.toml
index 89fab8c..8ff261b 100644
--- a/harrogate/Cargo.toml
+++ b/harrogate/Cargo.toml
@@ -22,6 +22,7 @@ valentines-2020 = ["replace-default"]
 st-patricks-day = ["replace-default"]
 july-4 = ["replace-default"]
 halloween-2020 = ["replace-default"]
+halloween-2021 = ["replace-default"]
 new-years-eve-2020 = ["replace-default"]
 november-2020 = ["replace-default"]
 
diff --git a/harrogate/src/halloween_2021.rs b/harrogate/src/halloween_2021.rs
new file mode 100644
index 0000000..f270a8b
--- /dev/null
+++ b/harrogate/src/halloween_2021.rs
@@ -0,0 +1,58 @@
+//! purple-and-green with "lightning" flashes
+use super::delay;
+use house::{Harrogate, PORCH_BACK_LEN, PORCH_FRONT_LEN};
+use lights::{murmurf, rgb::Rgb, HardwareRgb, Lights};
+
+const BLACK: Rgb = Rgb(0, 0, 0);
+const GREEN: Rgb = Rgb(0, 255, 0);
+const LIGHTNING: Rgb = Rgb(255, 200, 50);
+
+const PURPLE: Rgb = Rgb(100, 0, 128);
+
+// tenth of a second
+const TIC: u32 = 4_800_000;
+
+#[allow(dead_code)]
+#[inline(always)]
+pub fn run(lights: &mut impl Lights<Pixel = HardwareRgb>) -> ! {
+    let mut rng = 0xB00u32;
+    let mut back_buffer = [BLACK; PORCH_BACK_LEN];
+
+    let mut draw = |back_buffer: &[Rgb]| {
+        let front_pattern = [PURPLE].iter().cycle().cloned();
+        Harrogate {
+            porch_front: front_pattern.take(PORCH_FRONT_LEN),
+            porch_back: back_buffer.iter().cloned(),
+        }
+        .render_to(lights);
+    };
+
+    loop {
+        // clear
+        back_buffer.iter_mut().for_each(|pix| *pix = GREEN);
+        draw(&back_buffer);
+
+        // delay 3-15 seconds
+        delay(TIC * (murmurf(&mut rng) % 120 + 30));
+
+        // flash 1
+        back_buffer.iter_mut().for_each(|pix| *pix = BLACK);
+        flash(&mut rng, &mut back_buffer);
+        draw(&back_buffer);
+        delay(TIC * 2);
+
+        // flash 2
+        flash(&mut rng, &mut back_buffer);
+        draw(&back_buffer);
+        delay(TIC * 3);
+    }
+}
+
+fn flash(rng: &mut u32, back_buffer: &mut [Rgb]) {
+    let start = murmurf(rng) as usize % (PORCH_BACK_LEN - 20);
+    let len = murmurf(rng) as usize % 20 + murmurf(rng) as usize % 20 + 10;
+    let end = (start + len).min(PORCH_BACK_LEN);
+    back_buffer.as_mut()[start..end]
+        .iter_mut()
+        .for_each(|pix| *pix = LIGHTNING);
+}
diff --git a/harrogate/src/main.rs b/harrogate/src/main.rs
index 82bac7f..7b044c2 100644
--- a/harrogate/src/main.rs
+++ b/harrogate/src/main.rs
@@ -13,6 +13,7 @@ mod valentines_2020;
 mod st_patricks_day;
 mod july_4;
 mod halloween_2020;
+mod halloween_2021;
 mod november_2020;
 mod new_years_eve_2020;
 mod door_light;
@@ -45,6 +46,9 @@ fn main() -> ! {
     #[cfg(feature = "halloween-2020")]
     halloween_2020::run(&mut lights);
 
+    #[cfg(feature = "halloween-2021")]
+    halloween_2021::run(&mut lights);
+
     #[cfg(feature = "new-years-eve-2020")]
     new_years_eve_2020::run(&mut lights);