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

local st = require "util.stanza";

local mod_groups = module:depends("groups_internal")

local mod_pep = module:depends("pep")

local PUBSUB_NODE_XEP0048 = "storage:bookmarks";

local XMLNS_XEP0048 = "storage:bookmarks";

local XMLNS_XEP0060 = "http://jabber.org/protocol/pubsub";

local default_options = {

	["persist_items"] = true;

	["access_model"] = "whitelist";

};

local function get_current_bookmarks(jid, service)

	local ok, id, item = service:get_last_item(PUBSUB_NODE_XEP0048, jid)

	if not ok or id == nil then

		if id == "item-not-found" or id == nil then

			-- return empty

			return st.stanza("storage", { xmlns = XMLNS_XEP0048 });

		end

		return nil, result

	end

	-- first item is the actual storage element

	local hit = item:get_child("storage", XMLNS_XEP0048);

	if not hit then

		return nil, "internal-server-error"

	end

	return hit

end

local function update_bookmarks(jid, service, storage)

	local item = st.stanza("item", { xmlns = XMLNS_XEP0060, id = "current" }):add_child(storage)

	module:log("debug", "updating bookmarks with %q", item)

	local ok, err = service:publish(

		PUBSUB_NODE_XEP0048,

		jid,

		"current",

		item,

		default_options

	)

	if not ok then

		module:log("error", "failed to update bookmarks: %s", err)

	end

end

local function find_matching_bookmark(storage, room)

	for node in storage:childtags("conference") do

		if node.attr.jid == room then

			return node

		end

	end

	return nil

end

local function inject_bookmark(jid, room, autojoin, name)

	local pep_service = mod_pep.get_pep_service(jid_split(jid))

	autojoin = autojoin or false and true

	local current = get_current_bookmarks(jid, pep_service)

	local existing = find_matching_bookmark(current, room)

	if existing then

		if autojoin ~= nil then

			existing.attr.autojoin = autojoin and "true" or "false"

		end

		if name ~= nil then

			-- do not change already configured names

			if not existing.attr.name then

				existing.attr.name = name

			end

		end

		done = true

		module:log("debug", "found existing matching bookmark, updated")

	else

		module:log("debug", "no existing bookmark found, adding new")

		current:tag("conference", {

			name = name,

			autojoin = autojoin and "true" or "false",

			jid = room,

			xmlns = XMLNS_XEP0048,

		})

	end

	update_bookmarks(jid, pep_service, current)

end

local function remove_bookmark(jid, room, autojoin, name)

	local pep_service = mod_pep.get_pep_service(jid_split(jid))

	autojoin = autojoin or false and true

	local current = get_current_bookmarks(jid, pep_service)

	current:maptags(function (node)

		if node.attr.xmlns and node.attr.xmlns ~= XMLNS_XEP0048 then

			return node

		end

		if node.name ~= "conference" then

			return node

		end

		if node.attr.jid == room then

			-- remove matching bookmark

			return nil

		end

		return node

	end)

	update_bookmarks(jid, pep_service, current)

end

local function handle_user_added(event)

	if not event.group_info.muc_jid then

		module:log("debug", "ignoring user added event on group %s because it has no MUC", event.id)

		return

	end

	local jid = event.user .. "@" .. event.host

	inject_bookmark(jid, event.group_info.muc_jid, true, event.group_info.name)

end

local function handle_user_removed(event)

	if not event.group_info.muc_jid then

		module:log("debug", "ignoring user removed event on group %s because it has no MUC", event.id)

		return

	end

	-- Removing the bookmark is fine as the user just lost any privilege to

	-- be in the MUC (as group MUCs are members-only).

	local jid = event.user .. "@" .. event.host

	remove_bookmark(jid, event.group_info.muc_jid, true, event.group_info.name)

end

module:hook("group-user-added", handle_user_added)

module:hook("group-user-removed", handle_user_removed)