-- XEP-0313: Message Archive Management for Prosody

-- Copyright (C) 2011-2012 Kim Alvefur

--

-- This file is MIT/X11 licensed.

local xmlns_mam     = "urn:xmpp:mam:tmp";

local xmlns_delay   = "urn:xmpp:delay";

local xmlns_forward = "urn:xmpp:forward:0";

local st = require "util.stanza";

local rsm = module:require "mod_mam/rsm";

local jid_bare = require "util.jid".bare;

local jid_split = require "util.jid".split;

local jid_prep = require "util.jid".prep;

local host = module.host;

local dm_list_load = require "util.datamanager".list_load;

local dm_list_append = require "util.datamanager".list_append;

local tostring = tostring;

local time_now = os.time;

local m_min = math.min;

local timestamp, timestamp_parse = require "util.datetime".datetime, require "util.datetime".parse;

local uuid = require "util.uuid".generate;

local default_max_items, max_max_items = 20, module:get_option_number("max_archive_query_results", 50);

--local rooms_to_archive = module:get_option_set("rooms_to_archive",{});

-- TODO Should be possible to enforce it too

local archive_store = "archive2";

-- Handle archive queries

module:hook("iq/bare/"..xmlns_mam..":query", function(event)

	local origin, stanza = event.origin, event.stanza;

	local room = jid_split(stanza.attr.to);

	local query = stanza.tags[1];

	local room_obj = hosts[module.host].modules.muc.rooms[jid_bare(stanza.attr.to)];

	if not room_obj then

		return -- FIXME not found

	end

	local from = jid_bare(stanza.attr.from);

	if room_obj._affiliations[from] == "outcast"

		or room_obj._data.members_only and not room_obj._affiliations[from] then

		return -- FIXME unauth

	end

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

		local qid = query.attr.queryid;

		-- Search query parameters

		local qwith = query:get_child_text("with");

		local qstart = query:get_child_text("start");

		local qend = query:get_child_text("end");

		local qset = rsm.get(query);

		module:log("debug", "Archive query, id %s with %s from %s until %s)",

			tostring(qid), qwith or "anyone", qstart or "the dawn of time", qend or "now");

		if qstart or qend then -- Validate timestamps

			local vstart, vend = (qstart and timestamp_parse(qstart)), (qend and timestamp_parse(qend))

			if (qstart and not vstart) or (qend and not vend) then

				origin.send(st.error_reply(stanza, "modify", "bad-request", "Invalid timestamp"))

				return true

			end

			qstart, qend = vstart, vend;

		end

		local qres;

		if qwith then -- Validate the 'with' jid

			local pwith = qwith and jid_prep(qwith);

			if pwith and not qwith then -- it failed prepping

				origin.send(st.error_reply(stanza, "modify", "bad-request", "Invalid JID"))

				return true

			end

			local _, _, resource = jid_split(qwith);

			qwith = jid_bare(pwith);

			qres = resource;

		end

		-- Load all the data!

		local data, err = dm_list_load(room, module.host, archive_store);

		if not data then

			if (not err) then

				module:log("debug", "The archive was empty.");

				origin.send(st.reply(stanza));

			else

				origin.send(st.error_reply(stanza, "cancel", "internal-server-error", "Error loading archive: "..tostring(err)));

			end

			return true

		end

		-- RSM stuff

		local qmax = m_min(qset and qset.max or default_max_items, max_max_items);

		local qset_matches = not (qset and qset.after);

		local first, last, index;

		local n = 0;

		local start = qset and qset.index or 1;

		module:log("debug", "Loaded %d items, about to filter", #data);

		for i=start,#data do

			local item = data[i];

			local when, nick = item.when, item.resource;

			local id = item.id;

			--module:log("debug", "id is %s", id);

			-- RSM pre-send-checking

			if qset then

				if qset.before == id then

					module:log("debug", "End of matching range found");

					qset_matches = false;

					break;

				end

			end

			--module:log("debug", "message with %s at %s", with, when or "???");

			-- Apply query filter

			if (not qres or (qres == nick))

					and (not qstart or when >= qstart)

					and (not qend or when <= qend)

					and (not qset or qset_matches) then

				local fwd_st = st.message{ to = stanza.attr.from }

					:tag("result", { xmlns = xmlns_mam, queryid = qid, id = id }):up()

					:tag("forwarded", { xmlns = xmlns_forward })

						:tag("delay", { xmlns = xmlns_delay, stamp = timestamp(when) }):up();

				local orig_stanza = st.deserialize(item.stanza);

				orig_stanza.attr.xmlns = "jabber:client";

				fwd_st:add_child(orig_stanza);

				origin.send(fwd_st);

				if not first then

					index = i;

					first = id;

				end

				last = id;

				n = n + 1;

			elseif (qend and when > qend) then

				module:log("debug", "We have passed into messages more recent than requested");

				break -- We have passed into messages more recent than requested

			end

			-- RSM post-send-checking

			if qset then

				if qset.after == id then

					module:log("debug", "Start of matching range found");

					qset_matches = true;

				end

			end

			if n >= qmax then

				module:log("debug", "Max number of items matched");

				break

			end

		end

		-- That's all folks!

		module:log("debug", "Archive query %s completed", tostring(qid));

		local reply = st.reply(stanza);

		if last then

			-- This is a bit redundant, isn't it?

			reply:query(xmlns_mam):add_child(rsm.generate{first = first, last = last, count = n});

		end

		origin.send(reply);

		return true

	end

end);

-- Handle messages

local function message_handler(event)

	local origin, stanza = event.origin, event.stanza;

	local orig_type = stanza.attr.type or "normal";

	local orig_to = stanza.attr.to;

	local orig_from = stanza.attr.from;

	-- Still needed?

	if not orig_from then

		orig_from = origin.full_jid;

	end

	-- Only store groupchat messages

	if not (orig_type == "groupchat" and (stanza:get_child("body") or stanza:get_child("subject"))) then

		return;

	end

	local room = jid_split(orig_to);

	local room_obj = hosts[host].modules.muc.rooms[orig_to]

	if not room_obj then return end

	local id = uuid();

	local when = time_now();

	local stanza = st.clone(stanza); -- Private copy

	--stanza.attr.to = nil;

	local nick = room_obj._jid_nick[orig_from];

	if not nick then return end

	stanza.attr.from = nick;

	local _, _, nick = jid_split(nick);

	-- And stash it

	local ok, err = dm_list_append(room, host, archive_store, {

		-- WARNING This format may change.

		id = id,

		when = when,

		resource = nick,

		stanza = st.preserialize(stanza)

	});

	--[[ This was dropped from the spec

	if ok then 

		stanza:tag("archived", { xmlns = xmlns_mam, by = host, id = id }):up();

	end

	--]]

end

module:hook("message/bare", message_handler, 2);

module:add_feature(xmlns_mam);