[RGSS] Heretic's Unlimited Battle Page Conditions (edited)

#=============================================================================
#
#           Unlimited Battle Page Conditions
#           Authors: Heretic (edited by LiTTleDRAgo)
#           Version 1.0
#           Monday, January 20th, 2014
#
#-----------------------------------------------------------------------------
#
#  ---   OVERVIEW   ---
#
#  This script will allow you to add an Unlimited Number of Page Conditions
#  for Battle Events by using Comments as a Condition on each Battle Page
#
#  ---   IMPORTANT!   ---
#
#  The Conditions that you put in to the Comment MUST be able to evaluate
#  to true / false!
#
#  What this means is that a Condition of var = 1 will run, but not evaluate
#  to true, so it wont ever be recognized as a valid condition.  By placing
#  a Condition of "if var == 1" will return true, which makes it valid when
#  the proper conditions are met.
#
#  ---   USAGE   ---
#
#  Create a Condition by making a Comment ANYWHERE on a Battle Event Page
#  with "condition:" followed by your Scripted Condition in the Comment.
#
#  Example #1:
#
#  @>Comment:  condition:  if $foo == $bar
#
#
#  Comment Conditions will run Eval for ALL of the contents for each Comment
#  all at once.  This allows you to have a Multi Line Condition.
#
#  Example #2:
#
#  @>Comment:  condition:  if ($foo == $bar and
#                             $lorem == $ipsum)
#
#
#  Comments run as Scripts just like a Script Event, so you can put anything
#  into the Script.  Loops, Iterations, Create Variables, Self Switches, etc.
#
#  Example #3
#
#  @>Comment:  condition:  result = false
#                          for actor in $game_party.actors
#                            if actor.weapon_id == 12
#                              result = true
#                            end
#                          end
#                          return true if result == true
#
#
#  Each Comment Condition you add will add another Condition to check before
#  the Battle Event Page can be run.  This allows you to add as many Conditions
#  as you want.  THERE IS NO LIMIT.  Each Comment Condition is considered as
#  its own Condition.
#
#  Example #4:
#
#  @>Comment: condition: $game_party.actors[0].hp == $game_party.actors[0].maxhp &&
#  @>Comment: $game_party.actors[0].id == 2
#
#  In the above example, BOTH Conditions MUST BE MET for the Battle Event Page
#  to be considered Valid and thus run.
#
#
#  You can use OR Statements inside of a single Comment Condition allowing for
#  greater flexibility of Battle Page Conditions.
#
#  Examle #5:
#
#  @>Comment: condition: if $foo == $bar OR $lorem == $ipsum
#
#
#  ANY Sript Logic can be used provided it fits in the comment.  Its all
#  evaluated the same way.
#
#  ---   BATTLE EVENTING   ---
#
#  Battle Eventing has a Menu for a few things already.  Such as checking to
#  make sure a certain Switch is on before running the Battle Event Page.  You
#  can now use a Comment Condition to check if a certain Switch is OFF before
#  running a Battle Event Page.
#
#  Battle Event also uses what is called SPAN.
#
#  SPAN controls when and how many times to run a Battle Event Page.
#
#  Span:   Battle - Page runs ONCE per the entire Battle
#  Turn:   Page runs ONCE per Turn, even if conditions are still met.
#  Moment: Runs when Conditions are met, and continues to run as long as
#          those conditions are met.
#
#  Comment Conditions are EXTREMELY USEFUL for allowing a Span Moment Page
#  to STOP RUNNING.  It allows you to run the Page once.  Like a specific
#  enemy has a State of "Immune to Fire", run some dialogue once, then
#  use some variable to set that the page has run already.  You could use
#  a Switch, or even any other variable like @this_page_ran = true, and set
#  that as a Condition.
#
#  Example #6
#
#  @>Comment:  condition:  if $game_troop.enemies[0].states.include?(12)
#                            @this_new_var_for_page_ran = true
#                          else
#                            unless @this_new_var_for_page_ran
#                              @this_new_var_for_page_ran = false
#                            end
#                          end
#  @>Conditional Branch:  Script: @this_new_var_for_page_ran != true
#    @>Text:  "Don't cast Fire on him!  He is now Immune to Fire!"
#  @>End Branch
#
#  ---   COMMAND LIST   ---
#
#  I'd like to make this as easy as possible for people to use.  So to do that
#  these list of Commands should make adding Comment Conditions easier.
#
#  Example of Command:
#
#  - item_in_inventory?(item_id)
#
#  @>Comment  condition: # If Party has a Potion in their Inventory
#                        if item_in_inventory(1)
#
#
#  Command List
#  - item_in_inventory?(item_id)
#
#-----------------------------------------------------------------------------
#==============================================================================
# ** Scene_Battle
#------------------------------------------------------------------------------
#  This class performs battle screen processing.
#==============================================================================
class Scene_Battle
  #--------------------------------------------------------------------------
  # * Battle Event Setup
  #
  #   - Replacement for default XP Battle System setup_battle_event
  #   - Any Script Conflicts would most likely come from this method
  #--------------------------------------------------------------------------
  def setup_battle_event
    # If battle event is running
    return if $game_system.battle_interpreter.running?
    # Search for all battle event pages
    for index in 0...$data_troops[@troop_id].pages.size
      # Get event pages
      page = $data_troops[@troop_id].pages[index]
      # Make event conditions possible for reference with c
      c = page.condition

      # This code is mostly default with the addition of "page_condition_valid"
      # Go to next page if no conditions are appointed
      unless c.turn_valid || c.enemy_valid || c.actor_valid || c.switch_valid ||
        page.cond_eval_valid
        next
      end

      # Default code
      # Go to next page if action has been completed
      next if $game_temp.battle_event_flags[index]
      # Confirm turn conditions
      if c.turn_valid
        n, a, b = $game_temp.battle_turn, c.turn_a, c.turn_b
        m = (n < 1 || n < a || n % b != a % b)
        next if (b == 0 && n != a) || (b > 0 && m)
      end
      # Confirm enemy conditions
      if c.enemy_valid
        enemy = $game_troop.enemies[c.enemy_index]
        next if enemy == nil or enemy.hp * 100.0 / enemy.maxhp > c.enemy_hp
      end
      # Confirm actor conditions
      if c.actor_valid
        actor = $game_actors[c.actor_id]
        next if actor == nil or actor.hp * 100.0 / actor.maxhp > c.actor_hp
      end
      # Confirm switch conditions
      if c.switch_valid
        next unless $game_switches[c.switch_id]
      end

      # This small block is also all that was added to the Default code
      # Confirm Page Condition (if Additional Page Condition exists)
      if (cond = page.cond_eval_valid)
        # If running the extra Page Condition returns false (which is default)
        next unless eval(cond)
      end

      # The rest of the code in this method is Default
      # Set up event
      $game_system.battle_interpreter.setup(page.list, 0)
      # If this page span is [battle] or [turn]
      # Set action completed flag
      $game_temp.battle_event_flags[index] = true if page.span <= 1
      return
    end
  end
  #--------------------------------------------------------------------------#
  # **  Custom Commands for Easy Checks for Conditional Switches             #
  #                                                                          #
  #             ALL METHODS MUST RETURN TRUE OR FALSE                        #
  #--------------------------------------------------------------------------#

  #--------------------------------------------------------------------------
  # * Item In Inventory
  #     item_id : Item Id from Database
  #
  #   Example: 1 is a Potion
  #            # If Party has a Potion in the Inventory
  #            item_in_inventory?(1)
  #
  #            2 is a High Potion
  #            # If Party has a High Potion in the Inventory
  #            item_in_inventory?(2)
  #
  #  This is an Example Script.  It could be accomplished by copying and
  #  pasting the one "return true if ..." line of code.  I provided this
  #  because it makes it easy for us to script easier condition checks
  #  for others that may use this script.
  #--------------------------------------------------------------------------
  def item_in_inventory?(item_id)
    # If Item is in Inventory, return True
    return true if $game_party.item_number(item_id) > 0
    # Default
    return false
  end
end

#==============================================================================
# ** Game_Enemy
#------------------------------------------------------------------------------
#  This class handles enemies. It's used within the Game_Troop class
#  ($game_troop).
#==============================================================================
class Game_Enemy
  #--------------------------------------------------------------------------
  # * Public Instance Variables
  #--------------------------------------------------------------------------
  attr_accessor :escaped                   # escaped flag
  #--------------------------------------------------------------------------
  # * Alias Listing
  #--------------------------------------------------------------------------
  $@ || alias_method(:escaped_flag_addition, :escape)
  #--------------------------------------------------------------------------
  # * Escape
  #--------------------------------------------------------------------------
  define_method(:escape){|*s| (@escaped = true) && escaped_flag_addition(*s)}
end

#==============================================================================
# ** Scene_Battle
#------------------------------------------------------------------------------
#  This class performs battle screen processing.
#==============================================================================
class Scene_Battle
  #--------------------------------------------------------------------------
  # * Alias Listing
  #--------------------------------------------------------------------------
  $@ || alias_method(:escaped_judge, :judge)
  #--------------------------------------------------------------------------
  # * Shortcut
  #--------------------------------------------------------------------------
  define_method(:all_visible_defeated?) { visible_enemies.empty?   }
  define_method(:all_hidden_defeated?)  { unescaped_enemies.empty? }
  #--------------------------------------------------------------------------
  # * Frame Update (main phase step 1 : action preparation)
  #--------------------------------------------------------------------------
  def judge(*args)
    if all_visible_defeated? #&& !all_hidden_defeated?
      setup_battle_event
      return false if $game_system.battle_interpreter.running?
    end
    escaped_judge(*args)
  end
  #--------------------------------------------------------------------------
  # * unescaped_enemies
  #--------------------------------------------------------------------------
  def unescaped_enemies
    $game_troop.enemies.select {|e| !e.dead? && e.hidden && !e.escaped }
  end
  #--------------------------------------------------------------------------
  # * visible_enemies
  #--------------------------------------------------------------------------
  def visible_enemies
    $game_troop.enemies.select {|e| !e.dead? && !e.hidden }
  end
end


#==============================================================================
# ** Interpreter
#------------------------------------------------------------------------------
#  This interpreter runs event commands. This class is used within the
#  Game_System class and the Game_Event class.
#==============================================================================
class Interpreter
  #--------------------------------------------------------------------------
  # * Alias Listing
  #--------------------------------------------------------------------------
  $@ || alias_method(:escaped_command_335, :command_335)
  #--------------------------------------------------------------------------
  # * Enemy Appearance
  #--------------------------------------------------------------------------
  def command_335(*args)
    enemy = $game_troop.enemies[@parameters[0]]
    enemy && enemy.escaped = false
    escaped_command_335(*args)
  end
end

#==============================================================================
# ** RPG::Troop::Page
#------------------------------------------------------------------------------
#
#==============================================================================
class RPG::Troop::Page
  #--------------------------------------------------------------------------
  # * cond_eval_valid
  #--------------------------------------------------------------------------
  def cond_eval_valid
    @cond_eval.nil? ? @cond_eval ||= get_cond_eval : @cond_eval
  end
  #--------------------------------------------------------------------------
  # * Eval Page Conditions
  #   - Finds ALL Page Conditions in Comments, then Evaluates them
  #
  #   NOTE: Conditions MUST be able to return a Value
  #         $foo = "Bar" will not return anything, thus evals to False
  #         if $foo == "Bar" will return either True or False
  #
  #   This code will check to enusre ALL of the Comment Conditions on a
  #   Battle Event Page are met.  If you have Two Conditions, both must
  #   eval to True for an Event Page to be considered "valid".  Each Comment
  #   Condition is considered as a Separate Condition.  Everything in the
  #   Comment Box is evaluated all at once, so you can create temporary
  #   variables, Loops, OR statements, etc as long as it is all contained
  #   in ONE Comment.  IE "if $foo == $bar OR actor_id == 2".  Complex
  #   scripts may adversely affect performance.
  #
  #   This is NEW CODE and should not cause any Script Conflicts.
  #
  #--------------------------------------------------------------------------
  def get_cond_eval
    for i in 0...list.size
      # If Command is First Line of a Comment
      next unless list[i].code == 108
      # Check each Commment if it has "condition:" as String
      condition = $1 if list[i].parameters[0][/^condition:\s*(.*)/i]
      # If Battle Condition in a Comment
      next unless condition
      # Check for more lines in the Comment to Eval all at once
      while (list[i + 1] and [108,408].include?(list[i + 1].code))
        # Add Next Line of Comment (code 408) to Condition to eval
        condition += "\n" + list[i += 1].parameters[0]
      end
      return condition
    end
    return false
  end
end