Breathing underwater

src/main/java/micdoodle8/mods/galacticraft/core/entities/player/GCPlayerHandler.java

@@ -998,6 +998,7 @@ public void onPlayerUpdate(EntityPlayerMP player) {
 
         // This will speed things up a little
         final GCPlayerStats GCPlayer = GCPlayerStats.get(player);
+        OxygenUtil.applyWaterBreathingEffect(player);
 
         if (ConfigManagerCore.challengeSpawnHandling && GCPlayer.unlockedSchematics.size() == 0) {
             if (GCPlayer.startDimension.length() > 0) {

src/main/java/micdoodle8/mods/galacticraft/core/util/OxygenUtil.java

@@ -21,6 +21,8 @@
 import net.minecraft.entity.EntityLivingBase;
 import net.minecraft.entity.player.EntityPlayerMP;
 import net.minecraft.item.ItemStack;
+import net.minecraft.potion.Potion;
+import net.minecraft.potion.PotionEffect;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.AxisAlignedBB;
 import net.minecraft.util.MathHelper;
@@ -423,4 +425,34 @@ public static boolean inOxygenBubble(World worldObj, double avgX, double avgY, d
 
         return false;
     }
+
+    /**
+     * Applies the water breathing effect to the player if they are in water and have the oxygen gear. Consumes oxygen
+     * from the player's oxygen tanks.
+     *
+     * @param player The player to check and apply the effect to.
+     */
+    public static void applyWaterBreathingEffect(EntityPlayerMP player) {
+        // Check if the player is in water
+        if (player.isInWater()) {
+            // Check if the player has valid oxygen gear setup
+            if (hasValidOxygenSetup(player)) {
+                // Apply the water breathing effect
+                player.addPotionEffect(new PotionEffect(Potion.waterBreathing.id, 220, 0, true));
+
+                // Consume oxygen
+                GCPlayerStats stats = GCPlayerStats.get(player);
+                ItemStack tankInSlot1 = stats.extendedInventory.getStackInSlot(2);
+                ItemStack tankInSlot2 = stats.extendedInventory.getStackInSlot(3);
+
+                if (tankInSlot1 != null && tankInSlot1.getItem() instanceof ItemOxygenTank
+                        && tankInSlot1.getMaxDamage() - tankInSlot1.getItemDamage() > 0) {
+                    tankInSlot1.damageItem(1, player);
+                } else if (tankInSlot2 != null && tankInSlot2.getItem() instanceof ItemOxygenTank
+                        && tankInSlot2.getMaxDamage() - tankInSlot2.getItemDamage() > 0) {
+                            tankInSlot2.damageItem(1, player);
+                        }
+            }
+        }
+    }
 }