#!/usr/bin/env ruby
#
# Copyright (c) 2013 Rui Paulo <rpaulo@FreeBSD.org>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS O R
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

require 'rubygems'
require 'open-uri'
require 'nokogiri'
require 'tzinfo'
require 'ri_cal'

debug = true
require 'awesome_print' if debug

timetable = "http://2013.asiabsdcon.org/timetable.html"

if debug
	doc = Nokogiri::HTML(File.open("test.html"))
else
	doc = Nokogiri::HTML(open(timetable))
end

days = []
rooms = []

# Find all the days
doc.xpath("//h2").each do |h2|
	day = h2.text.match("(\\(.*\\))")
	if day != nil
		days.push(day.to_s[/[^()]+/])
	end
end
ap days if debug

# Find all the rooms
doc.xpath("//div/table/thead/tr/th").each do |th|
	room = th.text
	if room.match("Room") and rooms.index(room) == nil
		rooms.push(room)
	end
end
ap rooms if debug

# Find all the events
events = []
currentday = 0
doc.xpath("//div/table").each do |table|
	# XXX fix entries that span multiple rows
	table.xpath("tbody/tr").each do |tr|
		time = tr.at("th").text.split("-")
		tstart = DateTime.parse(days[currentday] + " " + time[0])
		tend = DateTime.parse(days[currentday] + " " + time[1])
		tstart.set_tzid("Asia/Tokyo")
		tend.set_tzid("Asia/Tokyo")

		currentroom = 0
		tr.xpath("td").each do |td|
			event = {}
			if td.text == "-" or td.text == "Lunch" or
			   td.text == "Break"
				next
			end
			anchor = td.search("a").first
			if anchor == nil
				event[:title] = td.text
			else
				event[:title] = anchor.text
				event[:url] = timetable + anchor.attr("href")
			end
			event[:person] = td.search("i").text.split(" (eml")[0]
			event[:tstart] = tstart
			event[:tend] = tend
			event[:room] = rooms[currentroom]
			events.push(event)
			currentroom += 1
		end
	end
	currentday += 1
end
ap events if debug

# Build the Calendar file
ics = RiCal.Calendar do |cal|
	events.each do |event|
		cal.event do |calevent|
			summary = event[:title]
			if event[:person]
				summary += " - " + event[:person]
			end
			calevent.summary = summary
			calevent.dtstart = event[:tstart]
			calevent.dtend = event[:tend]
			calevent.location = event[:room]
			if event[:url]
				calevent.url = event[:url]
			end
		end
	end
end

print ics