module Accordion
  
  def open_page stack
    
    #scrolls through all the slots in the application
    #trying to determine which stack is active
    #this application consists of three slots -- each with two stacks.
    #In each slot, the second stack (the stack with the poem) is the 
    #stack that you care about.  By checking the height of the stack
    #with the detect function, you can determine if this is the 
    #active stack.  If the height is greater then zero, then the poem is
    #being shown to the user, thus, it IS the active stack, thus it
    #is returned to the user in the active variable
    active = app.contents.map { |x| x.contents[1] }.
      detect { |x| x.height > 0 }
    
    #if the stack is alreay active then return having
    #done nothing
    return if active == stack
    
    #animate the accordian like affect of hiding one poem
    #while showing another - animation is at 60 fps
    a = animate 60 do
      #add 20 pixles to the newly clicked stack height each go around
      #while subtracting the pixels from the previously active stack.
      stack.height += 20
      active.height = 240 - stack.height if active
      
      #and stop when the newly clicked stack height is equal to 240 pixles
      a.stop if stack.height == 240
    end
  end
  
  def page title, text
    
    #set pages equal to to the already existing array pages
    #or if it doesn't exist set it to a blank array
    @pages ||= []
    
    #add the stack element to the @pages array
    @pages <<
    
      #the stack is actually comprised of two stacks
      #the first one begins here and consist of the text
      #of the poem the second is the header bar to the poem
      #which contains the title
      stack do
        #set the initial page text to nil
        page_text = nil
        #begin the 'title bar' stack
        stack :width => "100%" do
          #set the background to a greyish gradient
          background "#fff".."#eed"
          #the 'hi' variable contains the background style that
          #the user will see when he hovers his mouse over the 
          #title bar
          hi = background "#ddd".."#ba9", :hidden => true
          #the title name itself is made a link that when clicked
          #will call the 'open_page' function while sending in the 
          #'page_text' variable
          para link(title). 
            click { open_page page_text }, :size => 26
          #if the user hovers with his mouse, the 'hi' background is shown
          hover { hi.show }
          #if the user's mouse leaves the title, the original background is shown
          leave { hi.hide }
          #if the title bar itself is clicked, the open_page function is called
          click { open_page page_text }
        end
        
        #now the the actual page_text is set.
         page_text =
          #if this is the first page, the height is set to 240 pixels
          #the rest of the pages are set to zero height to start
            stack :width => "100%", :height => (@pages.empty? ? 240 : 0) do
              stack :margin => 10 do
                #when two or more newlines are found, this means a line has been found
                #put that line in the stack
                text.split(/\n{2,}/).each do |pg|
                  para text
               end
              end
            end
        
      end
  end
end

#This is where your shoes app begins!
Shoes.app do
  extend Accordion
  
#set the style of the various link attributes throughout the application  
style(Link, :stroke => black, :underline => nil, :weight => "strong")
style(LinkHover, :stroke => black, :fill => nil, :underline => nil)

#puts a call to the 'page' function in the accordian class while sending 
#in two variables.  The first is 0.0.
#<<-'END' means read all the text from here to 'END'
#So the text starting from "There is" to "mental slippage.\n" is sent
#to the page function
  page "0.0", <<-'END'
There is a thought
I have just had
Which I don’t care to pass to
Anyone at all at this time.

I have even forgotten it now,
But kept only the pleasures
Of my property
And of my controlled mental slippage.
END

#second call to the page function
page "0.1", <<-'END'
My eyes have blinked again
And I have just realized
This upright world
I have been in.

My eyelids wipe
My eyes hundreds of times
Reseting and renovating
The scenery.
END

#third call to the page function
  page "0.2", <<-'END'
Sister, without you,
The universe would
Have such a hole through it,
Where infinity has been shot.

This cannot be, though.
There will always be room
For you—all of us are
Holding the way open.
END

end