From aed804863b14984f735cb2c5f3bc9d947fea5390 Mon Sep 17 00:00:00 2001
From: Elijah Voigt <elijah.caine.mv@gmail.com>
Date: Sat, 7 Dec 2024 22:37:44 -0800
Subject: [PATCH] Simple deck shuffling

---
 src/deck.rs  | 26 +++++++++++++++++++++++---
 src/setup.rs |  2 +-
 todo.txt     |  8 ++++++++
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/src/deck.rs b/src/deck.rs
index d14b230..9bc328a 100644
--- a/src/deck.rs
+++ b/src/deck.rs
@@ -1,4 +1,7 @@
-use bevy::{prelude::*, utils::HashMap};
+use bevy::{
+    prelude::*,
+    utils::{HashMap, RandomState},
+};
 
 /// Deck and Cards
 pub struct DeckPlugin;
@@ -16,7 +19,7 @@ pub(crate) struct Deck {
 }
 
 impl Deck {
-    pub(crate) fn iter_cards() -> impl Iterator<Item = Card> {
+    pub(crate) fn cards() -> Vec<Card> {
         let mut v = Vec::new();
 
         [ItemColor::Red, ItemColor::Green, ItemColor::Purple]
@@ -41,8 +44,25 @@ impl Deck {
                             });
                     });
             });
+        v
+    }
+
+    pub(crate) fn iter_cards() -> impl Iterator<Item = Card> {
+        Self::cards().into_iter()
+    }
 
-        v.into_iter()
+    pub(crate) fn shuffled() -> impl Iterator<Item = Card> {
+        let rs = RandomState::new();
+        let mut base = Self::cards();
+        let len = base.len();
+        (1..len).into_iter().for_each(|i| {
+            let a = rs.hash_one(base[i]) % (len as u64);
+            let b = rs.hash_one(base[i - 1]) % (len as u64);
+            if a > b {
+                base.swap(a as usize, b as usize);
+            }
+        });
+        base.into_iter()
     }
 }
 
diff --git a/src/setup.rs b/src/setup.rs
index 1fa3873..7cc3618 100644
--- a/src/setup.rs
+++ b/src/setup.rs
@@ -21,7 +21,7 @@ impl Plugin for SetupPlugin {
 /// Setup drawing our cards on the screen
 pub(crate) fn setup_cards(mut commands: Commands, deck: Res<Deck>) {
     let size = 75.0;
-    Deck::iter_cards().enumerate().for_each(|(i, this_card)| {
+    Deck::shuffled().enumerate().for_each(|(i, this_card)| {
         let this = deck
             .cards
             .get(&this_card)
diff --git a/todo.txt b/todo.txt
index f179baf..2188e0b 100644
--- a/todo.txt
+++ b/todo.txt
@@ -4,3 +4,11 @@ TODO:
 * Shuffle deck
 * Serve out 12 cards
 * Deal out additional cards after set captured
+* Reset game (click new game button)
+* Track score (number of sets)
+* Make button(s) look pretty
+* Make buttons react to hover/click!
+* Music!
+* Background!
+* Print "no set"/"too many cards" messages
+* Add "quit game" button