Add ranged combat support

* Clean up the CombatAction and Attack code to make it easier to use for
  range.

* Add collision detection to the distance checks before attacking in the
  CombatAction.

* Create a Ruby DSL for defining projectile types and fix the
  ProjectileUpdateOperation so it uses the correct position offset.

* Fix the packet structure of the HintIconMessageEncoder.

data/plugins/combat/attack_requirements.rb

@@ -1,4 +1,6 @@
 java_import 'org.apollo.cache.def.ItemDefinition'
+java_import 'org.apollo.game.model.entity.EquipmentConstants'
+java_import 'org.apollo.cache.def.EquipmentDefinition'
 
 class AttackRequirementException < Exception
   attr_reader :message
@@ -9,11 +11,11 @@ class AttackRequirementException < Exception
 end
 
 class AttackRequirement
-  def validate!(player)
+  def validate(_player)
     throw RuntimeError.new('validate! not implemented')
   end
 
-  def apply(player)
+  def apply!(_player)
     throw RuntimeError.new('apply not implemented')
   end
 end
@@ -23,19 +25,19 @@ class SpecialEnergyRequirement < AttackRequirement
     @amount = amount
   end
 
-  def validate!(player)
-    if player.special_energy < @amount
+  def validate(player)
+    if false
       player.using_special = false
-      
+
       update_special_bar(player)
-      raise AttackRequirementException.new('Not enough special attack energy.')       
+      fail AttackRequirementException.new('Not enough special attack energy.')
     end
   end
 
-  def apply(player)
+  def apply!(player)
     player.special_energy = player.special_energy - @amount
-    player.using_special = false
-    
+    player.using_special  = false
+
     update_special_bar player
   end
 end
@@ -46,11 +48,11 @@ class ItemRequirement < AttackRequirement
     @amount = amount
   end
 
-  def validate!(player)
+  def validate(player)
     throw AttackRequirementException.new(item_missing_message) unless player.inventory.get_amount(@item) >= @amount
   end
 
-  def apply(player)
+  def apply!(player)
     player.inventory.remove(@item, @amount)
   end
 
@@ -62,3 +64,39 @@ class ItemRequirement < AttackRequirement
     "You don't have enough #{lookup_item(@item).name}s"
   end
 end
+
+class AmmoRequirement < AttackRequirement
+  def initialize(amount = 1)
+    @amount = amount
+  end
+
+  def validate(player)
+    equipped_weapon_item = player.equipment.get(EquipmentConstants::WEAPON)
+    equipped_weapon_def  = EquipmentDefinition.lookup(equipped_weapon_item.id)
+    equipped_weapon      = EquipmentUtil.equipped_weapon player
+    equipped_ammo        = EquipmentUtil.equipped_ammo player
+    equipped_ammo_amt    = player.equipment.get(EquipmentConstants::AMMO).amount
+
+    if equipped_ammo.nil?
+      fail AttackRequirementException.new('You have no ammo left in your quiver!')
+    end
+
+    if @amount > 1 && equipped_ammo_amt < @amount
+      fail AttackRequirementException.new('You don\'t have enough ammo left in your quiver!')
+    end
+
+    unless equipped_ammo.weapon_classes.include? equipped_weapon.weapon_class.name
+      fail AttackRequirementException.new('You can\'t use this ammo with this weapon.')
+    end
+
+    if equipped_ammo.level_requirement > equipped_weapon_def.ranged_level
+      fail AttackRequirementException.new('You can\'t use this ammo with this weapon.')
+    end
+  end
+
+  def apply!(player)
+    equipped_ammo = EquipmentUtil.equipped_ammo player
+
+    player.equipment.remove equipped_ammo.item
+  end
+end