From abc3ed3685eebd82a507251522b6fbf97fa16e53 Mon Sep 17 00:00:00 2001
From: scawful <justin.scofield@outlook.com>
Date: Sat, 17 Aug 2024 12:16:55 -0400
Subject: [PATCH] chore: Add error handling and precondition checks to
 ApplyPaletteWithTransparent method

---
 src/app/gfx/bitmap.cc | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/src/app/gfx/bitmap.cc b/src/app/gfx/bitmap.cc
index aa9a65a6..9ffb8aaf 100644
--- a/src/app/gfx/bitmap.cc
+++ b/src/app/gfx/bitmap.cc
@@ -399,6 +399,23 @@ absl::Status Bitmap::ApplyPaletteFromPaletteGroup(const SnesPalette &palette,
 
 absl::Status Bitmap::ApplyPaletteWithTransparent(const SnesPalette &palette,
                                                  int index, int length) {
+  if (index < 0 || index >= palette.size()) {
+    return absl::InvalidArgumentError("Invalid palette index");
+  }
+
+  if (length < 0 || length > palette.size()) {
+    return absl::InvalidArgumentError("Invalid palette length");
+  }
+
+  if (index + length > palette.size()) {
+    return absl::InvalidArgumentError("Palette index + length exceeds size");
+  }
+
+  if (surface_ == nullptr) {
+    return absl::FailedPreconditionError(
+        "Surface is null. Palette not applied");
+  }
+
   auto start_index = index * 7;
   palette_ = palette.sub_palette(start_index, start_index + 7);
   std::vector<ImVec4> colors;