#!/usr/bin/env ruby

##
# Convert a flat text file of lectures to HTML and output a schedule ical file
##

$LOAD_PATH << File.dirname(__FILE__)

require 'time'
require 'bibparse'
require 'yaml'

LECTUREFILE = 'lectures.txt'
BIBFILE = "./class.bib"
SLIDETYPES = ["pdf", "ps", "html", "ppt", "key", "odp", "mp3", "mov", "txt"]
SIZETYPES = ["mp3", "mov"]
SLIDEDIR = "lectures"

class LecPrinter

  def initialize(lecfile, bibparse=nil)
    @lecfile = lecfile
    @bp = bibparse
    @start_time = nil
    @end_time = nil
    @year = nil
    @instructor = nil
    @term = nil
    @summary = nil
    @class_name = nil

    readlecs(lecfile)
  end
  

  def print_ical
    out = File.new("#{@class_short}.ics", "w+")
      out.puts %Q{
           BEGIN:VCALENDAR
           VERSION:2.0
           X-WR-CALNAME:#{@conf["CLASS_SHORT"].to_s.downcase}
           X-WR-TIMEZONE:US/Eastern
           CALSCALE:GREGORIAN
        }.gsub(/^\s*/, '')

    @lectures.each { |l|
      next if l["type"] != "lecture"
        class_summary = @conf['CLASS_SHORT'] + ' (' +l["T"] + ' - '  + l["I"] + ')'
	class_desc = class_summary + '       '
	if l["R"] != nil
	    class_desc += ' Readings: ' + l["R"].to_s + '       '
	end
	if l["N"] != nil
	    class_desc += ' Notes: ' + l["N"]
	end
        out.puts %Q{
            BEGIN:VEVENT
            DTSTART;TZID=US/Eastern:#{l['stime'].strftime("%Y%m%dT%H%M00")}
            DTEND;TZID=US/Eastern:#{l['etime'].strftime("%Y%m%dT%H%M00")}
            SUMMARY:#{class_summary}
            DESCRIPTION:#{class_desc}
            END:VEVENT
         }.gsub(/^\s*/, '')
    }

    out.puts "END:VCALENDAR"
  end

  def print_html
    print IO.read("syllabus.head")
    puts "<!-- Note:  Do not edit this file directly!  Edit syllabus.head, syllabus.tail, and lectures.txt -->"

    rowcount = 0
    @lectures.each { |l|

      ltype = l["type"]

      if (l["type"] == "lecture")
	# allow a wash on alternating rows
	if (@conf["ALTERNATE"] == 'row') 
	  if ((rowcount & 1) == 1)
	    ltype += " alt"
	  end
	  rowcount += 1
	elsif (@conf["ALTERNATE"] == 'week') 
	  weeknum = l['stime'].strftime("%U")
	  if ((weeknum.to_i & 1) == 1)
	    ltype += " alt"
	  end
	end
      end

      puts "<tr class=\"#{ltype}\">"

      if (l["type"] == "lechead")
	
	puts %Q{ <td class="#{ltype}" colspan="#{@conf["HEADSPAN"]}">#{l["T"]}</td>}
	puts "</tr>";
	next
      end

      if (@conf["SHOW_LECNUM"])
	if l["type"] == "lecture"
	  puts " <td>#{l["lecnum"]}</td>"
	else
	  puts " <td></td>"
	end
      end
      puts " <td>#{l["date"]}</td>"
      
      if (@conf["SHOW_INSTRUCTOR"])
	puts " <td>#{l["I"]}</td>"
      end

      tspan = ""
      if (l["TSPAN"])
          tspan = " colspan=\"#{l["TSPAN"]}\""
      end
      puts " <td#{tspan}>#{l["T"]} <br />"

      if (l["S"])
	SLIDETYPES.each { |ext|
	  filename = SLIDEDIR + "/" + l["S"] + "." + ext
	  if (FileTest.exists?(filename))
            size = ""
            if (SIZETYPES.include?(ext))
              bytes = FileTest.size(filename)
              size = sprintf(" (%.1f MB) ", bytes.to_f/(1024.0*1024.0))
            end
             
	    print "[<a href=\"#{filename}\">#{ext}</a>#{size}] "
	  end
	}
      end
      
      if (l["V"] && l["V"].to_s.length > 0)
	vcount = 1
	l["V"].to_s.split.each { |v|
	  print "[<a href=\"#{@videobase.sub("VIDEOID", v)}\">Video #{vcount}</a>] "
	  vcount += 1
	}
      end
      
      puts " </td>"
      
      # Notes
      if (!l["TSPAN"] || l["TSPAN"].to_i <= 1)
	  if (l["N"] =~ /Due/i && @conf["HIGHLIGHT_DUE"]) 
	      puts " <td class=\"due\">#{l["N"]}</td>"
	  else
	      puts " <td>#{l["N"]}</td>"
	  end
      end
      
      if (!l["TSPAN"] || l["TSPAN"].to_i <= 2)
      # Readings
	  print " <td>#{l["R"]} "
      
	  # Links for Readings
	  if (l["RL"] && l["RL"].length > 0)
	      rlcount = 1


            l["RL"].split.each { |rl|
            ref = rl.split('::')
            print "<a href=\"#{@readingbase}#{ref[1]}\">#{ref[0]}</a> "
          }
	  end
      
	  # Bibtex-Based Links for Readings
          first = true
	  if (l["RB"] && l["RB"].length > 0)
	      l["RB"].split.each { |rb|
  	        ref = rb.split('::')
	        url = ref[1]
	        if (url !~ /^http/) 
	          url = @readingbase.to_s + "/" + url.to_s
	        end
	        @bp.setURL(ref[0],url)
	        # add to the reading list
	        @bp.addToList(ref[0], l)
                prettyref = ref[0].gsub("_", " ")
                if (!first)
                    print ", "
                end
                first = false
	        print "<a href=\"#{url}\">#{prettyref}</a>"
             }
	  end
          puts " </td>"
      end
      
      puts "</tr>"
    }

    puts "</table>"
    
    print IO.read("syllabus.tail")
  end
    
  def readlecs(lecfile)
    @conf = YAML::load_file(lecfile)

    @year = @conf['YEAR']
    @summary = @conf['SUMMARY']
    @class_name = @conf['CLASS']
    @class_short = @conf['CLASS_SHORT'] + '-' +
      @conf['TERM'] + @conf['YEAR'].to_s
    @instructor = @conf['INSTRUCTOR']
    @videobase = @conf['VIDEOBASE']
    @readingbase = @conf['READINGBASE']
    @start_time = @conf['START_TIME']
    @end_time = @conf['END_TIME']

    lecnum = 1
  
    @lectures = Array.new
    @conf['LECTURES'].each { |l|

      if (l.class == String)
	lec = Hash.new
	lec["type"] = "lechead"
	lec["T"] = l.dup
      else

	key = l.keys[0]
        if (l[key] != nil)
          lec = l[key].dup
        else
          lec = Hash.new
        end

	lec["type"] ||= "lecture"

	if (lec["type"] == "lecture") 
	  lec["lecnum"] = lecnum
          lecnum = lecnum + 1
	end

	lec["year"] = @year
	m, d, y = key.split("/") # obtuse.  we store in hash keyed by date
	lec["day"] = d
	lec["month"] = m
	if (y)
	  lec["year"] = y
	end
	lec["START"] ||= @start_time
	lec["END"] ||= @end_time
	lec["I"] ||= @instructor

	shour, smin = lec["START"].split(":")
	ehour, emin = lec["END"].split(":")
	lec["stime"] = Time.local(lec["year"].to_i, lec["month"].to_i, lec["day"].to_i,
			   shour.to_i, smin.to_i, 0)
	lec["etime"] = Time.local(lec["year"].to_i, lec["month"].to_i, lec["day"].to_i,
			   ehour.to_i, emin.to_i, 0)
	lec["date"] = lec["stime"].strftime("%a %m/%d")
      end

      @lectures.push(lec)
    }
  end
end

bp = nil
if (FileTest.exists?(BIBFILE))
  bp = BibParse.new(BIBFILE)
end
lp = LecPrinter.new(LECTUREFILE, bp)

lp.print_html
lp.print_ical
    
if (bp) 
  bp.printReadingList("readinglist.html",
		      "readinglist.head",
		      "readinglist.tail")
end