Fix keybindings cannot be set to any modifier key

src/main/java/committee/nova/mkb/mixin/MixinMinecraft.java

@@ -2,11 +2,16 @@
 
 import committee.nova.mkb.util.Utilities;
 import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.GuiControls;
+import net.minecraft.client.gui.GuiScreen;
+import net.minecraft.client.settings.KeyBinding;
+import org.lwjgl.input.Keyboard;
 import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.Redirect;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 
 @Mixin(Minecraft.class)
@@ -16,8 +21,31 @@ public abstract class MixinMinecraft {
     @Final
     public static boolean isRunningOnMac;
 
+    @Shadow
+    public GuiScreen currentScreen;
+
+    @Shadow
+    public static long getSystemTime() {
+        throw new RuntimeException("Mixin application failed!");
+    }
+
     @Inject(method = "setIngameFocus", at = @At(value = "INVOKE", target = "Lnet/minecraft/util/MouseHelper;grabMouseCursor()V"))
     public void inject$setIngameFocus(CallbackInfo ci) {
         if (!isRunningOnMac) Utilities.updateKeyBindState();
     }
+
+    @Redirect(method = "func_152348_aa", at = @At(value = "INVOKE", target = "Lnet/minecraft/client/settings/KeyBinding;getKeyCode()I"))
+    public int redirect$dispatchKeyPresses$1(KeyBinding instance) {
+        final int original = instance.getKeyCode();
+        return Utilities.isActiveIgnoreKeyCode(instance) ? original : original + Integer.MIN_VALUE;
+    }
+
+    @Inject(method = "func_152348_aa", at = @At("TAIL"))
+    public void inject$dispatchKeyPresses(CallbackInfo ci) {
+        if (Keyboard.getEventKey() == 0 || Keyboard.isRepeatEvent()) return;
+        if (!(currentScreen instanceof GuiControls)) return;
+        final GuiControls controls = (GuiControls) currentScreen;
+        if (getSystemTime() - controls.field_152177_g < 20L) return;
+        if (!Keyboard.getEventKeyState()) controls.buttonId = null;
+    }
 }