[Ace] Generic Popup

#==============================================================================
# Iavra Generic Popup 1.01
# -----------------------------------------------------------------------------
# Description:
# Provides a generic way to display popup messages.
# -----------------------------------------------------------------------------
# Prerequisites:
# None
# -----------------------------------------------------------------------------
# How to Use:
# To show a new popup message, call the following method:
#
# IAVRA::POPUP.show("abc")
#
# The window height will automatically fit to the number of text lines.
#
# The method takes an optional hash, which can be used to override the default
# settings on a per-window basis, like this:
#
# IAVRA::POPUP.show("abc", {:width => 200})
#
# Also, the method can take an optional block, that will be called once the
# popup window is created. "self" inside the proc is set to the window itself:
#
# IAVRA::POPUP.show("abc") { p self }
#
# You can use all message codes in your text, but need to double backslashes
# for everything except newlines (\n).
#
# The popup will fade out over time and dispose itself afterwards.
#
# Popups are global and will persist between scenes. Certain scenes can be set
# to dispose existing popups by modifying the DISPOSE_ON_SCENE constant.
# -----------------------------------------------------------------------------
# Terms of Use:
# Free to use for both commercial and non-commercial games. Please give credit.
# -----------------------------------------------------------------------------
# Credits:
# Iavra
# -----------------------------------------------------------------------------
# Changelog:
# - 1.00: Release version.
# - 1.01: Changed the way popup options are handled. The show method now takes
#         an optional hash, that can be used to override the global defaults
#         on a per-window basis. Everything except the z-index can be modified.
#==============================================================================

($imported ||= {})[:iavra_generic_popup] = true

#==============================================================================
# ▼ IAVRA::POPUP
#==============================================================================

module IAVRA
    module POPUP

        #==========================================================================
        # ■ ■ ■ ■ ■ CONFIGURATION ■ ■ ■ ■ ■
        #==========================================================================

        #==========================================================================
        # Default options when creating new windows. Can be overriden on a per-
        # window basis by using the "options" parameter:
        #
        # :width =>         Window width
        # :min_lines =>     Minimum number of lines to display. Can be nil.
        # :max_lines =>     Maximum number of lines to display. Can be nil.
        # :line_height =>   Height of a single line. Set to nil for default.
        # :padding =>       Window padding. Set to nil for default.
        # :spacing =>       Spacing between windows. The update method can use this.
        # :windowskin =>    Windowskin to be used. Set to nil for default.
        # :fade_delay =>    Number of frames before the window starts fading.
        # :fade_rate =>     Rate at which the window fades out after the delay.
        # :update_method => Update method to be used.
        #==========================================================================

        DEFAULT_OPTIONS = {
            :width => 400,
            :min_lines => nil,
            :max_lines => nil,
            :line_height => nil,
            :padding => nil,
            :spacing => 10,
            :windowskin => nil,
            :fade_delay => 120,
            :fade_rate => 10,
            :update_method => :push_older_up
        }

        #==========================================================================
        # Z-index of the popup viewport.
        #==========================================================================

        Z_INDEX = 1

        #==========================================================================
        # When a scene listed in here becomes active, all popups will be disposed.
        # Add Scene_Base to dispose all popups whenever a scene changes.
        #==========================================================================

        DISPOSE_ON_SCENE = [
            Scene_Title, Scene_Gameover, Scene_File
        ]

        #==========================================================================
        # ■ ■ ■ ■ ■ CONFIGURATION ■ ■ ■ ■ ■
        #==========================================================================

        #==========================================================================
        # A number of predefined update methods, accessible by symbol. You can add
        # new ones if you know what to do. The update method takes 2 parameters:
        # - The list of all currently displayed windows.
        # - The index of the window, which is updated.
        #
        # Also, "self" inside the proc is set to the window itself.
        #==========================================================================

        UPDATE_PROCS = {

            # This can be used in combination with the callback proc to animate the
            # popups by other means, like "Iavra Animate Everything".

            :none => lambda {|list, index|},

            # This method displays popups in the lower left corner and adds new ones
            # on top. Once an older popup fades out, the remaining ones move down.

            :add_on_top => lambda {|list, index|
                self.y = Graphics.height - list.map.with_index{|w, i|
                    (i <= index) && !w.disposed? ? (w.height + w.spacing) : 0
                }.reduce(:+)
            },

            # This method displays popups in the lower left corner and adds new ones
            # to the bottom, pushing older ones upward.

            :push_older_up => lambda {|list, index|
                self.y = Graphics.height - list.map.with_index{|w, i|
                    (i >= index) && !w.disposed? ? (w.height + w.spacing) : 0
                }.reduce(:+)
            }

            # Be free to add your own methods here.
        }

        #==========================================================================
        # All popups are displayed in their own viewport. The viewport never gets
        # disposed, but since it's used throughout the whole game, this shouldn't
        # be too much of a problem.
        #==========================================================================

        VIEWPORT = Viewport.new
        VIEWPORT.z = Z_INDEX

        #==========================================================================
        # For storing the active popups.
        #==========================================================================

        @popups = []

        #==========================================================================
        # Adds a new popup window with the given text. Message codes can be used.
        #
        # An optional hash be can given to overwrite some of the default options.
        #
        # Can be called with an optional block that will be called, once the popup
        # is created.
        #==========================================================================

        def self.show(text, options = {}, &callback)
            @popups << Window_Popup.new(text, options, &callback)
        end

        #==========================================================================
        # Called every frame by Scene_Base to update popup position and opacity.
        #==========================================================================

        def self.update
            @popups.each {|popup| popup.update}
        end

        #==========================================================================
        # Called on scene exit to dispose all popups an clear the list.
        #==========================================================================

        def self.cleanup
            return unless DISPOSE_ON_SCENE.map{|scene| SceneManager.scene.is_a?(scene)}.any?
            @popups.each {|popup| popup.dispose}
            @popups.clear
        end

        #==========================================================================
        # Toggles visibility on or off for all popups.
        #==========================================================================

        def self.hide_all
            @popups.each {|popup| popup.visible = false}
        end

        def self.show_all
            @popups.each {|popup| popup.visible = true}
        end

        #==========================================================================
        # Returns the list of all currently displayed popups.
        #==========================================================================

        def self.list
            @popups
        end

        #==========================================================================
        # ▼ IAVRA::POPUP::Window_Popup
        # -------------------------------------------------------------------------
        # The popup window class. Namespaced to prevent possible conflicts with
        # other popup scripts.
        #==========================================================================

        class Window_Popup < ::Window_Base

            attr_reader :spacing

            #========================================================================
            # Initializes a new popup window. First merges the default options with
            # the given overrides (if any) and then initializes the window:
            #
            # - Set line_height, padding, spacing, fade delay and fade rate according
            #   to the options.
            #
            # - Calculates the number of text lines needed by using a dummy window.
            #   Then caps that value at the lower and upper bounds, if any.
            #
            # - Initializes the window, sets the viewport and windowskin. The window
            #   is created outside the visible part of the screen, since the update
            #   method will define it's position during the first update.
            #
            # - Draws the text (again).
            #
            # - Defines the given update method on the singleton class.
            #
            # - Executes the given callback proc, if any.
            #========================================================================

            def initialize(text, options = {}, &callback)
                o = DEFAULT_OPTIONS.merge(options)

                # window settings
                @line_height, @padding, @spacing, @fade_delay, @fade_rate =
                o.values_at(:line_height, :padding, :spacing, :fade_delay, :fade_rate)

                # calculate height
                dummy = Window_Dummy.new(text)
                lines = dummy.iavra_popup_num_lines
                dummy.dispose
                lines = [(min = o[:min_lines] || lines), (o[:max_lines] || min), lines].sort[1]
                height = fitting_height(lines)

                # initialize
                super(0, -height, o[:width], height)
                self.viewport = VIEWPORT
                self.windowskin = Cache.system(o[:windowskin]) if o[:windowskin]

                # draw text
                draw_text_ex(0, 0, text)

                # set update method
                define_singleton_method(:update_position, UPDATE_PROCS[o[:update_method]])

                # execute callback, if any
                instance_eval &callback if block_given?
            end

            #========================================================================
            # Line height
            #========================================================================

            def line_height
                @line_height || super
            end

            #========================================================================
            # Padding
            #========================================================================

            def standard_padding
                @padding || super
            end

            #========================================================================
            # Updates the position and opacity of the window
            #========================================================================

            def update
                super
                list = IAVRA::POPUP.list
                update_position(list, list.index(self))
                update_opacity
            end

            #========================================================================
            # Updates the opacity. Once it hits 0, the window is disposed and removes
            # itself from the list.
            #========================================================================

            def update_opacity
                if((@fade_delay -= 1) <= 0)
                    self.opacity -= @fade_rate
                    self.contents_opacity -= @fade_rate
                end
                if(self.opacity == 0)
                    dispose
                    IAVRA::POPUP.list.delete(self)
                end
            end

        end

        #==========================================================================
        # ▼ IAVRA::POPUP::Window_Dummy
        # -------------------------------------------------------------------------
        # A dummy window used to calculate the number of lines needed.
        #==========================================================================

        class Window_Dummy < ::Window_Base

            attr_reader :iavra_popup_num_lines

            def initialize(text)
                super(0, 0, 0, 0)
                @iavra_popup_num_lines = 1
                draw_text_ex(0, 0, text)
            end

            def process_new_line(text, pos)
                super(text, pos)
                @iavra_popup_num_lines += 1
            end

        end

    end
end

#==============================================================================
# ▼ Scene_Base
#==============================================================================

class Scene_Base

    alias :iavra_popup_update_all_windows :update_all_windows
    alias :iavra_popup_dispose_all_windows :dispose_all_windows

    #============================================================================
    # Updates all popup windows.
    #============================================================================

    def update_all_windows(*args)
        iavra_popup_update_all_windows(*args)
        IAVRA::POPUP.update
    end

    #============================================================================
    # Cleanup on scene end.
    #============================================================================

    def dispose_all_windows(*args)
        IAVRA::POPUP.cleanup
        iavra_popup_dispose_all_windows(*args)
    end

end

#==============================================================================
# ▼ SceneManager
#==============================================================================

module SceneManager

    class << self
        alias :iavra_popup_snapshot_for_background :snapshot_for_background
    end

    #============================================================================
    # Hide all popups before creating the background image, so they don't appear
    # on it.
    #============================================================================

    def self.snapshot_for_background
        IAVRA::POPUP.hide_all
        iavra_popup_snapshot_for_background
        IAVRA::POPUP.show_all
    end

end