local coroutine = coroutine;

local tonumber = tonumber;

local deadroutine = coroutine.create(function() end);

coroutine.resume(deadroutine);

module("httpstream")

local function parser(data, success_cb)

	local function readline()

		local pos = data:find("\r\n", nil, true);

		while not pos do

			data = data..coroutine.yield();

			pos = data:find("\r\n", nil, true);

		end

		local r = data:sub(1, pos-1);

		data = data:sub(pos+2);

		return r;

	end

	local function readlength(n)

		while #data < n do

			data = data..coroutine.yield();

		end

		local r = data:sub(1, n);

		data = data:sub(n + 1);

		return r;

	end

		local headers = {}; -- read headers

		while true do

			local line = readline();

			if line == "" then break; end -- headers done

			local key, val = line:match("^([^%s:]+): *(.*)$");

			if not key then coroutine.yield("invalid-header-line"); end -- TODO handle multi-line and invalid headers

			key = key:lower();

			headers[key] = headers[key] and headers[key]..","..val or val;

		end

		-- read body

		local len = tonumber(headers["content-length"]);

		len = len or 0; -- TODO check for invalid len

		local body = readlength(len);

		success_cb({

			method = method;

			path = path;

			httpversion = httpversion;

			headers = headers;

			body = body;

		});

	end

end

function new(success_cb, error_cb)

	local co = coroutine.create(parser);

	return {

		feed = function(self, data)

			if not data then

				co = deadroutine;

				return error_cb();

			end

			local success, result = coroutine.resume(co, data, success_cb);

			if result then

				co = deadroutine;

				return error_cb(result);

			end

		end;

	};

end

return _M;