[VXA] Ambush BGMs

#===============================================================================
#
# Ambush BGMs (1.0)
# 23/02/2012
# By Pacman (inspired by modern algebra)
# This script allows you to assign special BGMs for when the party is surprised
# by an enemy troop or preemptively attacks an enemy troop. You can also change
# the assigned BGM through a script call.
# Use the script calls:
# $game_system.preemptive_bbgm = "Name"
# $game_system.surprise_bbgm = "Name"
# To change, respectively, the preemptive or surprise BGMs to the music file
# (in the BGM folder) "Name". You may set the initial BGMs in the configuration
# below.
#
#===============================================================================
#
# START CONFIGURATION

module AMB_BGM  # Don't touch this.
  PREEMPTIVE = "Battle2"  # Preemptive battle music.
  SURPRISE = "Battle3"    # Surprise battle music.
end             # Don't touch this.

#
# END CONFIGURATION
#
#===============================================================================

#==============================================================================
# ■ BattleManager
#------------------------------------------------------------------------------
# 　戦闘の進行を管理するモジュールです。
#==============================================================================

module BattleManager
  class << self
    alias ambush_bgms init_members
    attr_reader :preemptive
    attr_reader :surprise
  end
end

#==============================================================================
# ■ Game_System
#------------------------------------------------------------------------------
# 　システム周りのデータを扱うクラスです。セーブやメニューの禁止状態などを保存
# します。このクラスのインスタンスは $game_system で参照されます。
#==============================================================================

class Game_System
  attr_accessor :preemptive_bbgm
  attr_accessor :surprise_bbgm
  alias ambush_bgms_init initialize
  def initialize(*a)
    @preemptive_bbgm = AMB_BGM::PREEMPTIVE
    @surprise_bbgm = AMB_BGM::SURPRISE
    ambush_bgms_init(*a)
  end
  alias ambush_bgms_bbgm battle_bgm
  def battle_bgm(*a)
    if BattleManager.preemptive
      RPG::BGM.new(@preemptive_bbgm)
    elsif BattleManager.surprise
      RPG::BGM.new(@surprise_bbgm)
    else
      ambush_bgms_bbgm(*a)
    end
  end
end

$imported ||= {}
$imported[:pac_ambush_bgms]

#===============================================================================
#
# END OF SCRIPT
#
#===============================================================================