Add support for combat related UI

* Allows switching between different combat styles, and updates the
  combat tabs styles for every equipped weapon. If a weapon with a
  special attack is equipped, the special bar for that interface will be
  shown.

* Adds a scheduled task which periodically restores special energy to
  the player and updates their special bar.

data/plugins/combat/widgets/combat_tab.rb

@@ -0,0 +1,70 @@
+java_import 'org.apollo.game.model.inter.InterfaceConstants'
+java_import 'org.apollo.game.model.entity.EquipmentConstants'
+java_import 'org.apollo.game.message.impl.SetWidgetTextMessage'
+java_import 'org.apollo.game.message.impl.SetInterfaceConfigMessage'
+java_import 'org.apollo.game.message.impl.ConfigMessage'
+java_import 'org.apollo.game.model.inv.SynchronizationInventoryListener'
+
+
+on :message, :item_option do |player, message|
+  update_combat_tab(player) if message.option == 2 and message.interface_id == SynchronizationInventoryListener::INVENTORY_ID
+end
+
+on :login do |event|
+  update_combat_tab(event.player)
+end
+
+on :message, :item_action do |player, message|
+  update_combat_tab(player) if message.interface_id == SynchronizationInventoryListener::EQUIPMENT_ID and message.slot == EquipmentConstants::WEAPON
+end
+
+
+on :message, :button do |player, msg|
+  weapon              = EquipmentUtil.equipped_weapon player
+  weapon_class        = weapon.weapon_class
+  weapon_class_widget = weapon_class.widget
+
+  next unless weapon_class_widget == msg.interface_id
+
+  if weapon_class.special_bar? and msg.button == weapon_class.special_bar_button
+    player.using_special = !player.using_special
+    update_special_bar(player)
+  else
+    player.combat_style = msg.button
+  end
+
+  update_combat_style player
+end
+
+private
+
+def update_combat_tab(player)
+  weapon              = EquipmentUtil.equipped_weapon player
+  weapon_name         = weapon.name
+  weapon_class        = weapon.weapon_class
+  weapon_class_widget = weapon_class.widget
+
+  attack_style_interface_layer = InterfaceConstants::UserInterface::ATTACK_STYLE.layer
+
+  player.interface_set.send_user_interface(attack_style_interface_layer, weapon_class_widget)
+  player.send SetWidgetTextMessage.new(weapon_class_widget, 0, weapon_name)
+
+  if weapon_class.special_bar?
+    player.send SetInterfaceConfigMessage.new(weapon_class_widget, weapon_class.special_bar_config, !weapon.special_attack?)
+  end
+
+  update_combat_style player
+end
+
+def update_combat_style(player)
+  weapon         = EquipmentUtil.equipped_weapon player
+  weapon_class   = weapon.weapon_class
+
+  # Update the combat style in case we had an invalid style selected, 
+  # and therefore reverted to the first combat style
+  selected_style = weapon_class.style_at(player.combat_style)
+
+  player.combat_style = weapon_class.button selected_style
+  player.send ConfigMessage.new(43, weapon_class.config(selected_style)) 
+end
+

data/plugins/combat/widgets/special_bar.rb

@@ -0,0 +1,23 @@
+java_import 'org.apollo.game.message.impl.ConfigMessage'
+
+def update_special_bar(player)
+  player.send(ConfigMessage.new(300, player.special_energy * 10)) # special energy
+  player.send(ConfigMessage.new(301, player.using_special ? 1 : 0)) # special enabled
+end
+
+on :login do |event|
+  player = event.player
+
+  update_special_bar player
+
+  schedule 25 do |task|
+    unless player.is_active
+      task.stop
+      next
+    end
+
+    player.special_energy = [player.special_energy + 5, 100].min
+    update_special_bar player
+  end
+end
+