ical.lua

module("ical", package.seeall)

local handler = {};

function handler.VEVENT(ical, line)

	local k,v = line:match("^(%w+):(.*)$");

	local curr_event = ical[#ical];

	if k and v then

		curr_event._last_key = k;

		curr_event[k] = v;

	elseif line:sub(1,1) == " " then

		curr_event[curr_event._last_key] = curr_event[curr_event._last_key]..line:sub(2);

		return;

	end

	if k == "DTSTAMP" then

		local t = {};

		t.year, t.month, t.day = v:match("^(%d%d%d%d)(%d%d)(%d%d)");

		t.hour, t.min, t.sec = v:match("T(%d%d)(%d%d)(%d%d)Z$");

		for k,v in pairs(t) do t[k] = tonumber(v); end

		curr_event.when = os.time(t);

	end

end

function load(data)

	local ical, stack = {}, {};

	local line_num = 0;

	-- Parse

	local hold_buffer;

	for line in data:gmatch("(.-)[\r\n]+") do

		line_num = line_num + 1;

		if line:match("^BEGIN:") then

			local type = line:match("^BEGIN:(%S+)");

			table.insert(stack, type);

			table.insert(ical, { type = type }); 

		elseif line:match("^END:") then

			if stack[#stack] ~= line:match("^END:(%S+)") then

				return nil, "Parsing error, expected END:"..stack[#stack].." before line "..line_num;

			end

			table.remove(stack);

		elseif handler[stack[#stack]] then

			handler[stack[#stack]](ical, (hold_buffer or "")..line);

		end

	end

	-- Return calendar

	return ical;

end

return _M;