From b82fdbca001e28abad5374fd458abaedb438d9ac Mon Sep 17 00:00:00 2001
From: geemili <opensource@geemili.xyz>
Date: Tue, 23 Apr 2024 22:17:35 -0600
Subject: [PATCH] fix: memory leak from snapshot/undo system

---
 src/main.zig | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/main.zig b/src/main.zig
index 74f19cc..61f086d 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -111,6 +111,7 @@ pub fn init(context: *seizer.Context) !void {
 }
 
 fn resetGame() !void {
+    resetHistory();
     draw_pile.deinit(gpa);
     draw_pile_exhausted = false;
     drawn_cards.shrinkRetainingCapacity(0);
@@ -151,6 +152,11 @@ fn resetHistory() void {
 
 fn destroy(window: *seizer.Window) void {
     _ = window;
+    for (history.items) |*snapshot| {
+        snapshot.deinit();
+    }
+    history.deinit(gpa);
+
     draw_pile.deinit(gpa);
     drawn_cards.deinit(gpa);
     for (&stacks) |*stack| {
@@ -454,7 +460,7 @@ pub fn doSelectOrPlace(pressed: bool) !void {
             }
         }
     } else if (hovered_deck == selected_deck) {
-        const snapshot = try Snapshot.initFromCurrentGlobalState();
+        var snapshot = try Snapshot.initFromCurrentGlobalState();
         const selected_substack = selected_deck.?.items[selected_card..];
 
         // try to move all selected cards into the foundations
@@ -488,12 +494,14 @@ pub fn doSelectOrPlace(pressed: bool) !void {
 
         if (cards_moved) {
             try history.append(gpa, snapshot);
+        } else {
+            snapshot.deinit();
         }
 
         selected_deck = null;
     } else {
         var cards_moved = false;
-        const snapshot = try Snapshot.initFromCurrentGlobalState();
+        var snapshot = try Snapshot.initFromCurrentGlobalState();
         if (selected_deck) |selected| move_from_selected_to_hovered: {
             const selected_substack = selected.items[selected_card..];
             if (selected_substack.len == 0) break :move_from_selected_to_hovered;
@@ -516,7 +524,7 @@ pub fn doSelectOrPlace(pressed: bool) !void {
                         hovered.ensureUnusedCapacity(gpa, 1) catch break :move_from_selected_to_hovered;
                         hovered.appendAssumeCapacity(selected_deck.?.pop());
                         hovered_card = indexOfTopOfStack(hovered_deck.?.items);
-                        try history.append(gpa, snapshot);
+                        cards_moved = true;
                         break :move_from_selected_to_hovered;
                     } else for (foundations[0..]) |*foundation| {
                         if (foundation != selected) continue;
@@ -550,6 +558,8 @@ pub fn doSelectOrPlace(pressed: bool) !void {
         }
         if (cards_moved) {
             try history.append(gpa, snapshot);
+        } else {
+            snapshot.deinit();
         }
         selected_deck = null;
     }
@@ -778,6 +788,12 @@ const Snapshot = struct {
     pub fn deinit(snapshot: *@This()) void {
         gpa.free(snapshot.draw_pile);
         gpa.free(snapshot.drawn_cards);
+        for (snapshot.stacks) |stack| {
+            gpa.free(stack);
+        }
+        for (snapshot.foundations) |foundation| {
+            gpa.free(foundation);
+        }
     }
 
     pub fn restore(snapshot: @This()) !void {