# Path to icalendar *.ics files on your server
PATH_ICS       = "#{RAILS_ROOT}/private/calendars/"
PATH_ICS_CACHE = "#{RAILS_ROOT}/tmp/calendars/"
FileUtils::mkdir_p(PATH_ICS)       unless File.exists?(PATH_ICS)
FileUtils::mkdir_p(PATH_ICS_CACHE) unless File.exists?(PATH_ICS_CACHE)

require 'vpim'
class CalendarsController < ApplicationController
 
  def index
    # Load parameters if submitted
    session[:date_year]  = params[:options]["date(1i)"] if !params[:options].blank? && !params[:options]["date(1i)"].empty?
    session[:date_month] = params[:options]["date(2i)"] if !params[:options].blank? && !params[:options]["date(2i)"].empty?
    session[:date_day]   = params[:options]["date(3i)"] if !params[:options].blank? && !params[:options]["date(3i)"].empty?
 
    # Load standard if nothing submitted
    session[:date_year]  = Time.now.year  if session[:date_year].blank?
    session[:date_month] = Time.now.month if session[:date_month].blank?
    session[:date_day]   = Time.now.day   if session[:date_day].blank?
 
    # Set variables
    @scope     = 7
    @events   = []
    @today    = Time.gm(session[:date_year], session[:date_month], session[:date_day])
    cachefile = File.join(PATH_ICS_CACHE, "#{@today.to_s(:ical)}_#{@scope}.yml")
 
    # Kill cache if outdated
    if File.exists?(cachefile)
      killcache = false
      Dir.glob(File.join(PATH_ICS, '*.ics')).each do |file|
        killcache = true if File.mtime(file) > File.mtime(cachefile)
      end
      if killcache
        Dir.glob(File.join(PATH_ICS_CACHE, '*.*')).each do |file|
          File.delete(file)
        end
      end
    end
 
    # Load calendar from cache
    if File.exists?(cachefile)
      @events = YAML.load_file cachefile 
    else
      # No cache, parse each icalendar *.ics file in PATH_ICS and check for event occurences
      Dir.glob(File.join(PATH_ICS, '*.ics')).each do |file|
        category = File.basename(file, '.ics')
        Vpim::Icalendar.decode(File.open(file)).each do |calendar|
          calendar.components do |event|
            for day in 0..@scope
              if start = event.occurs_in?(@today+(60*60*24*day), @today+(60*60*24)+(60*60*24*day))
                myend = start + (event.dtend - event.dtstart)
                @events < < {
                  'category' => category,
                  'day'      => day,
                  'start'    => start,
                  'duration' => ((event.dtend - event.dtstart) / 60).round, # In minutes
                  'end'      => myend,
                  'allday'   => start.hour == 0 && start.min == 0 && start.sec == 0 && myend.hour == 0 && myend.min == 0 && myend.sec == 0,
                  'data'     => event
                }
              end
            end
          end
        end
      end
      @events = @events.uniq # Just in case :)
      # Save cache
      File.open(cachefile, 'w') { |f| YAML.dump(@events, f) }
    end
  end
 
end

< %
  width  = 110      # Width of one day
  height = 6        # height of 15 minutes in pixels
  buffer = 28       # free space for dates in day column (at top of each day)
  minh   = 20       # Minimum of event height
  cutmornings = 120 # I don't have events between 0:00 and 6:00, cut these pixels off
%>
 
<div id="action">
 
< % for day in 0...@scope + 1 do 
  today = (@today+(60*60*24*day))
  case today.wday  
    when 0  
      dayclass = 'class="sunday"'
    when 6  
      dayclass = 'class="saturday"'
    else  
      dayclass = 'class="otherday"'
  end
  %>
  <div id="ical_day" <%= dayclass %>
    style=" width:  < %= width %>px;
            height: < %= height*96 + buffer - cutmornings %>px;
            left:   < %= day*width + day*10 %>px;">
    < % if today.year == Time.now.year && today.month == Time.now.month && today.day == Time.now.day %>
      <b>< %= 'Today' %></b>
    < % else %>
      < %= _(today.strftime("%a")) +', '+ today.to_s(:date) %>
    < % end %>
  </div>
< % end %>
 
< % tops = Array.new(@scope + 1, '')
@events.each do |event|
 
  # Exclude recurrence rule hack
  today = (@today+(60*60*24*event['day']))
  exme = false
  event['data'].propvaluearray('EXDATE').each do |exdate|
    exdate = exdate.to_time
    exme = true if today.year == exdate.year && today.mon == exdate.mon && today.day == exdate.day
  end
  next if exme # Skip this event
 
  if event['allday']
    # All-day events will be inserted later
    tops[event['day']] += '&nbsp; ' + event['data'].summary.to_s + '<br/>'
  else 
    eventheight = ((event['duration']/15)*height).round
    eventheight = minh if eventheight < minh
    %>
    <div id="ical_event"
      style=" background: #<%= eventcolor(event['category']) %>;
              width:  < %= width-2 %>px;
              height: < %= eventheight.to_s %>px;
              top:    < %= event['start'].hour*height*4 + (event['start'].min/15)*6 + buffer - cutmornings %>px;
              left:   < %= event['day']*width + event['day']*10 %>px;">
      < %= '<b>'+ event['start'].to_s(:time) +' - '+ event['end'].to_s(:time) +'<br />' %>
      < %= event['data'].summary %>
    </div>
  < % end %>
< % end %>
 
< % tops.each_with_index do |top, day| %>
    <div id="ical_event_top"
      style=" width: <%= width-2 %>px;
              height: < %= height %>px;
              top: < %= buffer %>px;
              left: < %= day * width + day * 10 %>px;">
      < %= top %>
    </div>
< % end %>
 
<div id="vertical_spacer" style="height: <%= height*96 + buffer*2 - cutmornings %>px;">&nbsp;</div>
 
</div>

module CalendarsHelper
 
  def eventcolor(category)
    case category  
      when 'Wichtig'   # This is the name of the .ics file
        return 'f66'
      when 'Sonstiges'
        return '4f4'
      when 'Studium'
        return 'fb4'
      when 'Privat'
        return '77f'
      when 'Freunde'
        return 'f4f'
      else  
        return 'fb4'
    end
  end
 
end

/**************** DIVs ***************************/
 
div#action {
  position: absolute;
  margin-left: 10px;
  margin-top: 10px;
  padding: 4px;
  border-left: 0px;
}
 
div#ical_day {
  position: absolute;
  padding-top: 5px;
  text-align: center;
  font-size: 10px;
}
 
.otherday {
  background: #ddd;
}
 
.sunday {
  background: #fdd;
}
 
.saturday {
  background: #ddf;
}
 
#ical_event {
  position: absolute;
  border: 1px #555 solid;
  background: #fb4;
  font-size: 8px;
  text-align: left;
}
 
#ical_event_top {
  position: absolute;
  border: 0px;
  font-size: 9px;
  font-weight: bold;
  text-align: left;
}
 
/**************** Fonts ***************************/
 
#title {
  float:right;
  color: #ddd;
  margin-top: 30px;
  margin-right: 10px;
  line-height: 11px;
  font-size: 16px;
  text-align: right;
}
#title .description {
  color: #777;
  font-size: 10px;
  margin: 0;
}

  # CALENDAR Controllers
  map.connect 'calendar', :controller => 'calendars'