require 'optparse'
require 'erb'
require 'RedCloth'
require 'BlueCloth'
require 'logger'


module Slideshow

class Params
  
  def initialize( title, name )
      @title   = title
      @svgname =  "#{name}.svg"
      @cssname =  "#{name}.css"
  end
    
  def params_binding
      binding
  end

end

def Slideshow.load_template( name )

  templatesdir = "#{File.dirname(__FILE__)}/templates"
  logger.debug "templatesdir=#{templatesdir}"

  File.read( "#{templatesdir}/#{name}" )
end

def Slideshow.render_template( content, b=TOPLEVEL_BINDING )
  ERB.new( content ).result( b )
end


def Slideshow.create_slideshow( fn )

  headerdoc   = load_template( 'header.html.erb' )
  footerdoc   = load_template( 'footer.html.erb' )
  styledoc    = load_template( 'style.css.erb' )
  gradientdoc = load_template( 'gradient.svg.erb' )

  basename = File.basename( fn, '.*' )
  extname  = File.extname( fn )

  params = Params.new( "Slideshow", basename )

  known_textile_extnames = [ '.textile', '.t' ]
  known_markdown_extnames =  [ '.markdown', '.mark', '.m', '.txt', '.text' ]
  known_extnames = known_textile_extnames + known_markdown_extnames
                
  if extname.eql?("") then
    extname  = ".textile"   # default to .textile 
    
    known_extnames.each { |e|
       logger.debug "File.exists? #{basename}#{e}"
       if File.exists?( "#{basename}#{e}" ) then         
          extname = e
          logger.debug "extname=#{extname}"
          break
       end
    }     
  end

  inname  =  "#{basename}#{extname}"
  outname =  "#{basename}.html"
  svgname =  "#{basename}.svg"
  cssname =  "#{basename}.css"

  logger.debug "inname=#{inname}"

  puts "Preparing slideshow stylesheet '#{cssname}'..."

  out = File.new( cssname, "w+" )
  out << render_template( styledoc, params.params_binding )
  out.flush
  out.close

  puts "Preparing slideshow theme '#{svgname}'..."
  
  out = File.new( svgname, "w+" )
  out << render_template( gradientdoc, params.params_binding )
  out.flush
  out.close 
  
  puts "Preparing slideshow '#{outname}'..."

  # convert light-weight markup to hypertext
 
  content = File.read( inname )
  
  if known_markdown_extnames.include?( extname )
    content = BlueCloth.new( content ).to_html
  else
    content = RedCloth.new( content ).to_html
  end
  

  # post-processing

  slide_counter = 0
  content2 = ''
  
  # wrap h1's in slide divs
  content.each_line { |line|
     if line.include?( '<h1>' ) then
        content2 << "\n\n</div>"  if slide_counter > 0
        content2 << "<div class='slide'>\n\n"
        slide_counter += 1
     end
     content2 << line
  }
  content2 << "\n\n</div>"   if slide_counter > 0

  out = File.new( outname, "w+" )
  out << render_template( headerdoc, params.params_binding )
  out << content2 
  out << render_template( footerdoc, params.params_binding )
  out.flush
  out.close

  puts "Done."
end

def Slideshow.logger 
   if @@logger.nil?
      @@logger = Logger.new(STDOUT)
   end
   @@logger
end

def Slideshow.main

  @@logger = nil
  $options = {}

  logger.level = Logger::INFO

  opt=OptionParser.new do |opts|
    opts.banner = "Usage: slideshow [options] name"
    # opts.on( "-s", "--style STYLE", "Select Stylesheet" ) { |s| $options[:style]=s }
    # opts.on( "-v", "--version", "Show version" )  {}
    opts.on( "-t", "--trace", "Show debug trace" ) {
       logger.datetime_format = "%H:%H:%S"
       logger.level = Logger::DEBUG
     }
    opts.on_tail( "-h", "--help", "Show this message" ) {
         puts 
         puts "Slide Show (S9) is a free web alternative to PowerPoint or KeyNote in Ruby"
         puts
         puts opts.help
         puts
         puts "Examples:"
         puts "  slideshow microformats"
         puts "  slideshow microformats.textile"
         puts
         puts "Further information:"
         puts "  http://slideshow.rubyforge.org" 
         exit
       }
  end

  opt.parse!

  puts "Slide Show (S9) Version: 0.3 on Ruby #{RUBY_VERSION} (#{RUBY_RELEASE_DATE}) [#{RUBY_PLATFORM}]"

  ARGV.each { |fn| Slideshow.create_slideshow( fn ) }
end

end