Kadafi - Checkpoint System

#==============================================================================
# Kadafi - Checkpoint System
# Version : 1.0
# Contact : http://forums.rpgmakerweb.com/index.php?/user/33654-kadafi/
#==============================================================================
($imported ||= {})[:Kadafi_CheckpointSystem] = true
#==============================================================================
# CHANGE LOGS:
# -----------------------------------------------------------------------------
# 2017.10.21 - Finished script
#==============================================================================
=begin

  Introduction :
  This script create a checkpoint system.

  How to Use :
  Edit the configuration below.

  Script Call :
  DataManager.save_checkpoint     # Save Checkpoint
  DataManager.delete_checkpoint   # Delete Checkpoint

  Terms of Use :
  1. Credit me as Kadafi (Optional)

=end
#==============================================================================
# Configuration
#==============================================================================
module Kadafi
  #--------------------------------------------------------------------------
  # * Game Over Window Width in Scene_GameOver
  #--------------------------------------------------------------------------
  GameOverWindow_Width = 180
  #--------------------------------------------------------------------------
  # * Load Checkpoint Vocab
  #--------------------------------------------------------------------------
  LoadCheckpoint_Vocab = "Load Checkpoint"
  #--------------------------------------------------------------------------
  # * Return Title Vocab
  #--------------------------------------------------------------------------
  ReturnTitle_Vocab = "Return Title"
end
#==============================================================================
# Don't edit below this line unless you know what to do.
#==============================================================================

#==============================================================================
# ** DataManager
#==============================================================================

module DataManager
  #--------------------------------------------------------------------------
  # * Module Instance Variables
  #--------------------------------------------------------------------------
  @last_checkpointfile_index = 0                # most recently accessed file
  #--------------------------------------------------------------------------
  # * Determine Existence of Checkpoint File
  #--------------------------------------------------------------------------
  def self.checkpoint_file_exists?
    !Dir.glob('Checkpoint*.rvdata2').empty?
  end
  #--------------------------------------------------------------------------
  # * Maximum Number of Checkpoint Files
  #--------------------------------------------------------------------------
  def self.checkpointfile_max
    return 1
  end
  #--------------------------------------------------------------------------
  # * Create Checkpoint Filename
  #     index : File Index
  #--------------------------------------------------------------------------
  def self.make_checkpoint_filename(index)
    sprintf("Checkpoint%02d.rvdata2", index + 1)
  end
  #--------------------------------------------------------------------------
  # * Execute Save Checkpoint
  #--------------------------------------------------------------------------
  def self.save_checkpoint
    begin
      save_checkpoint_without_rescue(0)
    rescue
      delete_checkpoint_file(0)
      false
    end
  end
  #--------------------------------------------------------------------------
  # * Execute Load Checkpoint
  #--------------------------------------------------------------------------
  def self.load_checkpoint
    load_checkpoint_without_rescue(0) rescue false
  end
  #--------------------------------------------------------------------------
  # * Load Checkpoint Header
  #--------------------------------------------------------------------------
  def self.load_header_2(index)
    load_header_2_without_rescue_2(index) rescue nil
  end
  #--------------------------------------------------------------------------
  # * Execute Save Checkpoint (No Exception Processing)
  #--------------------------------------------------------------------------
  def self.save_checkpoint_without_rescue(index)
    File.open(make_checkpoint_filename(index), "wb") do |file|
      $game_system.on_before_save
      Marshal.dump(make_checkpoint_header, file)
      Marshal.dump(make_checkpoint_contents, file)
      @last_checkpointfile_index = index
    end
    return true
  end
  #--------------------------------------------------------------------------
  # * Execute Load Checkpoint (No Exception Processing)
  #--------------------------------------------------------------------------
  def self.load_checkpoint_without_rescue(index)
    File.open(make_checkpoint_filename(index), "rb") do |file|
      Marshal.load(file)
      extract_checkpoint_contents(Marshal.load(file))
      reload_map_if_updated_2
      @last_checkpointfile_index = index
    end
    return true
  end
  #--------------------------------------------------------------------------
  # * Load Checkpoint Header (No Exception Processing)
  #--------------------------------------------------------------------------
  def self.load_header_2_without_rescue_2(index)
    File.open(make_checkpoint_filename(index), "rb") do |file|
      return Marshal.load(file)
    end
    return nil
  end
  #--------------------------------------------------------------------------
  # * Delete Checkpoint File
  #--------------------------------------------------------------------------
  def self.delete_checkpoint_file(index)
    File.delete(make_checkpoint_filename(index)) rescue nil
  end
  #--------------------------------------------------------------------------
  # * Delete Checkpoint
  #--------------------------------------------------------------------------
  def self.delete_checkpoint
    File.delete(make_checkpoint_filename(0)) rescue nil
  end
  #--------------------------------------------------------------------------
  # * Create Checkpoint Header
  #--------------------------------------------------------------------------
  def self.make_checkpoint_header
    header = {}
    header[:characters] = $game_party.characters_for_savefile
    header[:playtime_s] = $game_system.playtime_s
    header
  end
  #--------------------------------------------------------------------------
  # * Create Checkpoint Contents
  #--------------------------------------------------------------------------
  def self.make_checkpoint_contents
    contents = {}
    contents[:system]        = $game_system
    contents[:timer]         = $game_timer
    contents[:message]       = $game_message
    contents[:switches]      = $game_switches
    contents[:variables]     = $game_variables
    contents[:self_switches] = $game_self_switches
    contents[:actors]        = $game_actors
    contents[:party]         = $game_party
    contents[:troop]         = $game_troop
#~     contents[:map]           = $game_map
    contents[:player]        = $game_player
    contents
  end
  #--------------------------------------------------------------------------
  # * Extract Checkpoint Contents
  #--------------------------------------------------------------------------
  def self.extract_checkpoint_contents(contents)
    $game_system        = contents[:system]
    $game_timer         = contents[:timer]
    $game_message       = contents[:message]
    $game_switches      = contents[:switches]
    $game_variables     = contents[:variables]
    $game_self_switches = contents[:self_switches]
    $game_actors        = contents[:actors]
    $game_party         = contents[:party]
    $game_troop         = contents[:troop]
#~     $game_map           = contents[:map]
    $game_player        = contents[:player]
  end
  #--------------------------------------------------------------------------
  # * Reload Map if Data Is Updated
  #--------------------------------------------------------------------------
  def self.reload_map_if_updated_2
    if $game_system.version_id != $data_system.version_id
      $game_map.setup($game_map.map_id)
      $game_player.center($game_player.x, $game_player.y)
      $game_player.make_encounter_count
    end
  end
  #--------------------------------------------------------------------------
  # * Get Update Date of Checkpoint File
  #--------------------------------------------------------------------------
  def self.checkpointfile_time_stamp(index)
    File.mtime(make_checkpoint_filename(index)) rescue Time.at(0)
  end
  #--------------------------------------------------------------------------
  # * Get File Index with Latest Update Date
  #--------------------------------------------------------------------------
  def self.latest_checkpointfile_index
    checkpointfile_max.times.max_by {|i| checkpointfile_time_stamp(i) }
  end
  #--------------------------------------------------------------------------
  # * Get Index of File Most Recently Accessed
  #--------------------------------------------------------------------------
  def self.last_checkpointfile_index
    @last_checkpointfile_index
  end
end

class Scene_Gameover < Scene_Base
  alias old_start_1 start
  def start
    old_start_1
    create_command_window
  end

  # overwrites update method
  # prevents returning to title screen upon button press
  def update
    super
  end

  def pre_terminate
    super
    close_command_window
  end

  def create_command_window
    @command_window = Window_GameOver.new
    set_handlers
  end

  def set_handlers
    set_handlers_first
    @command_window.set_handler(:load, method(:command_load_checkpoint))
    @command_window.set_handler(:to_title, method(:goto_title))
    @command_window.set_handler(:shutdown, method(:command_shutdown))
    set_handlers_last
  end

  def set_handlers_first; end
  def set_handlers_last; end

  def close_command_window
    @command_window.close if @command_window
    update until @command_window.close?
  end

  alias old_goto_title_1 goto_title
  def goto_title
    fadeout_all
    old_goto_title_1
  end

  def command_load_checkpoint
    if DataManager.load_checkpoint
      Sound.play_load
      fadeout_all
      $game_system.on_after_load
      SceneManager.goto(Scene_Map)
    else
      Sound.play_buzzer
      @command_window.activate
    end
  end

  def command_shutdown
    SceneManager.exit
  end
end

class Window_GameOver < Window_Command
  def initialize
    super(0, 0)
    update_placement
    self.openness = 0
    open
  end

  def window_width
    return Kadafi::GameOverWindow_Width
  end

  def update_placement
    self.x = [(Graphics.width - width)/2, 0].max
    self.y = [(Graphics.height - height)/1.1, 0].max
  end

  def alignment
    return 1
  end

  def make_command_list
    add_commands_first
    add_command(Kadafi::LoadCheckpoint_Vocab, :load, can_load_checkpoint?)
    add_command(Kadafi::ReturnTitle_Vocab,    :to_title)
#~     add_command(Vocab::shutdown,  :shutdown)
    add_commands_last
  end

  def add_commands_first; end
  def add_commands_last; end

  def can_load_checkpoint?
    DataManager.checkpoint_file_exists?
  end
end