#!/usr/bin/env lua

 --

 --	$ bvvcal [bezirksname] [startdatum] [enddatum]

 --

 --	bezirksname : Default "friedrichshain-kreuzberg"

 --	startdatum : in deutscher Notation (z.B. 10.10.2010), Default: heute

 --	enddatum : Default: startdatum

 --

 --	Konvertiert den Berliner BVV-Sitzungskalender 

 --	ins iCalendar 2.0 (vCal) Format

 --

 --	Benötigt: 

 --	- htmltidy : http://tidy.sourceforge.net/

 --	- wget : http://www.gnu.org/software/wget/

 --	- Lua 5.1.x : http://www.lua.org/

 --	- LuaExpat : http://www.keplerproject.org/luaexpat/

 --

 local lxp = require "lxp"

 local district = arg[1] or "friedrichshain-kreuzberg"

 local startdate = arg[2] or os.date("%d.%m.%Y")

 local enddate = arg[3] or startdate

 local uid_uri = district .. ".bvv.berlin.piratenpartei.de"

 ----- --- --- -- - -  -   -    -

 local state = "waitcontent"

 local record, cell, result = { }, { }, { }

 local lnr = 1

 local parser = lxp.new {

 	StartElement = function(parser, tagname, attr)

 		if state == "waitcontent" then

 			if tagname == "div" and attr.id == "allrisContent" then

 				state = "waittab"

 			end

 		elseif state == "waittab" then

 			if tagname == "table" and attr.class == "tl1" then

 				state = "waitrow"

 			end

 		elseif state == "waitrow" then

 			if tagname == "tr" then

 				state = "waitcell"

 			end

 		end

 	end,

 	EndElement = function(parser, tagname)

 		if state == "waitrow" or state == "waittable" then

 			if tagname == "table" then

 				state = "end"

 			end

 		elseif state == "waitcell" then

 			if tagname == "tr" then

 				local day = table.remove(record, 1)

 				local sdate = table.remove(record, 1)

 				local d, m, y = (sdate or ""):match("^%s*(%d+)%.(%d+)%.(%d+)")

 				local time = table.remove(record, 1)

 				if d and m and y and time then

 					local sH, sM, eH, eM = time:match("^%s*(%d+):(%d+)%s*%-%s*(%d+):(%d+)")

 					if not sH then

 						sH, sM = time:match("^%s*(%d+):(%d+)")

 					end

 					if sH then

 						local what = table.concat(record, " "):match("^%s*(.-)%s*$")

 						table.insert(result, { y .. m .. d, sH .. sM, eH and eH .. eM, what })

 					end

 				end

 				state = "waitrow"

 				record = { }

 			elseif tagname == "td" then

 				table.insert(record, table.concat(cell))

 				cell = { }

 			end

 		end

 	end,

 	CharacterData = function(parser, s)

 		if state == "waitcell" then

 			table.insert(cell, s)

 		end

 	end

 }

 parser:setencoding("ISO-8859-1")

 ----- --- --- -- - -  -   -    -

 local cmd = ("wget --quiet --post-data 'kaldatvon=%s&kaldatbis=%s' 'http://www.berlin.de/ba-%s/bvv-online/si010.asp' -O - | tidy -latin1 -asxml -i -w 0 2>/dev/null -q"):format(startdate, enddate, district)

 -- print(cmd)

 local f = io.popen(cmd)

 for line in f:lines() do

 -- 	print(lnr .. " : " .. line)

 	parser:parse(line)

 	lnr = lnr + 1

 end

 ----- --- --- -- - -  -   -    -

 print "BEGIN:VCALENDAR"

 print "PRODID:BVV2CAL"

 print "VERSION:2.0"

 print ""

 for i = 1, #result do

 	local r = result[i]

 	print "BEGIN:VEVENT"

 	local start = r[1] .. "T" .. r[2]

 	print("UID:" .. start .. "." .. uid_uri)

 	print("SUMMARY:" .. r[4])

 	print("DTSTART:" .. start .. "00Z")

 	if r[3] then

 		print("DTEND:" .. r[1] .. "T" .. r[3] .. "00Z")

 	end

 	print "END:VEVENT"

 	print ""

 end

 print "END:VCALENDAR"