local http = require "net.http";

local json = require "util.json";

local st = require "util.stanza";

local xml = require "util.xml";

local unpack = rawget(_G, "unpack") or table.unpack;

local url = module:get_option_string("component_post_url");

assert(url, "Missing required config option 'component_post_url'");

local stanza_kinds = module:get_option_set("post_stanza_types", { "message" });

local http_error_map = {

	[0]   = { "cancel", "remote-server-timeout", "Connection failure" };

	-- 4xx

	[400] = { "modify", "bad-request" };

	[401] = { "auth", "not-authorized" };

	[402] = { "auth", "forbidden", "Payment required" };

	[403] = { "auth", "forbidden" };

	[404] = { "cancel", "item-not-found" };

	[410] = { "cancel", "gone" };

	-- 5xx

	[500] = { "cancel", "internal-server-error" };

	[501] = { "cancel", "feature-not-implemented" };

	[502] = { "cancel", "remote-server-timeout", "Bad gateway" };

	[503] = { "wait", "remote-server-timeout", "Service temporarily unavailable" };

	[504] = { "wait", "remote-server-timeout", "Gateway timeout" };

}

local function error_reply(stanza, code)

	local error = http_error_map[code] or { "cancel", "service-unavailable" };

	return st.error_reply(stanza, unpack(error, 1, 3));

end

function handle_stanza(event)

	local stanza = event.stanza;

	local request_body = json.encode({

		to = stanza.attr.to;

		from = stanza.attr.from;

		kind = stanza.name;

		body = stanza.name == "message" and stanza:get_child_text("body") or nil;

		stanza = tostring(stanza);

	});

	http.request(url, {

		body = request_body;

	}, function (response_text, code, response)

		if stanza.attr.type == "error" then return; end -- Avoid error loops, don't reply to error stanzas

		if code == 200 and response_text and response.headers["content-type"] == "application/json" then

			local response_data = json.decode(response_text);

			if response_data.stanza then

				local reply_stanza = xml.parse(response_data.stanza);

				if reply_stanza then

					reply_stanza.attr.from, reply_stanza.attr.to = stanza.attr.to, stanza.attr.from;

					module:send(reply_stanza);

				else

					module:log("warn", "Unable to parse reply stanza");

				end

			else

				local stanza_kind = response_data.kind or "message";

				local to = response_data.to or stanza.attr.from;

				local from = response_data.from or stanza.attr.to;

				local reply_stanza = st.stanza(stanza_kind, {

					to = to, from = from;

					type = response_data.type or (stanza_kind == "message" and "chat") or nil;

				});

				if stanza_kind == "message" and response_data.body then

					reply_stanza:tag("body"):text(tostring(response_data.body)):up();

				end

				module:log("debug", "Sending %s", tostring(reply_stanza));

				module:send(reply_stanza);

			end

		elseif code >= 200 and code <= 299 then

			return;

		else

			module:send(error_reply(stanza, code));

		end

		return true;

	end);

	return true;

end

for stanza_kind in stanza_kinds do

	for _, jid_type in ipairs({ "host", "bare", "full" }) do

		module:hook(stanza_kind.."/"..jid_type, handle_stanza);

	end

end

-- Simple handler for an always-online JID that allows everyone to subscribe to presence

local function default_presence_handler(event)

	local stanza = event.stanza;

	module:log("debug", "Handling %s", tostring(stanza));

	if stanza.attr.type == "probe" then

		module:send(st.presence({ to = stanza.attr.from, from = stanza.attr.to.."/default" }));

	elseif stanza.attr.type == "subscribe" then

		module:send(st.presence({ type = "subscribed", to = stanza.attr.from, from = stanza.attr.to.."/default" }));

		module:send(st.presence({ to = stanza.attr.from, from = stanza.attr.to.."/default" }));

	elseif stanza.attr.type == "unsubscribe" then

		module:send(st.presence({ type = "unavailable", to = stanza.attr.from, from = stanza.attr.to.."/default" }));

	end

	return true;

end

module:hook("presence/bare", default_presence_handler, -1);