-- luacheck: ignore 212/self

local sql = require "util.sql";

local xml_parse = require "util.xml".parse;

local resolve_relative_path = require "util.paths".resolve_relative_path;

local stanza_preserialize = require "util.stanza".preserialize;

local unpack = unpack

local function iterator(result)

	return function(result_)

		local row = result_();

		if row ~= nil then

			return unpack(row);

		end

	end, result, nil;

end

local default_params = { driver = "MySQL" };

local engine;

local host = module.host;

local room, store;

local function get_best_affiliation(a, b)

	if a == 'owner' or b == 'owner' then

		return 'owner';

	elseif a == 'administrator' or b == 'administrator' then

		return 'administrator';

	elseif a == 'outcast' or b == 'outcast' then

		return 'outcast';

	elseif a == 'member' or b == 'member' then

		return 'member';

	end

	assert(false);

end

local function keyval_store_get()

	if store == "config" then

		local room_jid = room.."@"..host;

		local result;

		for row in engine:select("SELECT `name`,`desc`,`topic`,`public`,`secret` FROM `rooms` WHERE `jid`=? LIMIT 1", room_jid or "") do result = row end

		local name = result[1];

		local desc = result[2];

		local subject = result[3];

		local public = result[4];

		local hidden = public == 0 and true or nil;

		local secret = result[5];

		if secret == '' then secret = nil end

		local affiliations = {};

		for row in engine:select("SELECT `jid_user`,`affil` FROM `rooms_lists` WHERE `jid_room`=?", room_jid or "") do

			local jid_user = row[1];

			local affil = row[2];

			-- mu-conference has a bug where full JIDs get stored…

			local bare_jid = jid_user:gsub('/.*', '');

			local old_affil = affiliations[bare_jid];

			-- mu-conference has a bug where it can record multiple affiliations…

			if old_affil ~= nil and old_affil ~= affil then

				affil = get_best_affiliation(old_affil, affil);

			end

			-- terminology is clearly “admin”, not “administrator”.

			if affil == 'administrator' then

				affil = 'admin';

			end

			affiliations[bare_jid] = affil;

		end

		return {

			jid = room_jid,

			_data = {

				persistent = true,

				name = name,

				description = desc,

				subject = subject,

				password = secret,

				hidden = hidden,

			},

			_affiliations = affiliations,

		};

	end

end

--- Key/value store API (default store type)

local keyval_store = {};

keyval_store.__index = keyval_store;

function keyval_store:get(roomname)

	room, store = roomname, self.store;

	local ok, result = engine:transaction(keyval_store_get);

	if not ok then

		module:log("error", "Unable to read from database %s store for %s: %s", store, roomname or "<host>", result);

		return nil, result;

	end

	return result;

end

function keyval_store:users()

	local host_length = host:len() + 1;

	local ok, result = engine:transaction(function()

		return engine:select("SELECT SUBSTRING_INDEX(jid, '@', 1) FROM `rooms`");

	end);

	if not ok then return ok, result end

	return iterator(result);

end

local stores = {

	keyval = keyval_store;

};

--- Implement storage driver API

-- FIXME: Some of these operations need to operate on the archive store(s) too

local driver = {};

function driver:open(store, typ)

	local store_mt = stores[typ or "keyval"];

	if store_mt then

		return setmetatable({ store = store }, store_mt);

	end

	return nil, "unsupported-store";

end

function driver:stores(roomname)

	local query = "SELECT 'config'";

	if roomname == true or not roomname then

		roomname = "";

	end

	local ok, result = engine:transaction(function()

		return engine:select(query, host, roomname);

	end);

	if not ok then return ok, result end

	return iterator(result);

end

--- Initialization

local function normalize_params(params)

	assert(params.driver and params.database, "Configuration error: Both the SQL driver and the database need to be specified");

	return params;

end

function module.load()

	if prosody.prosodyctl then return; end

	local engines = module:shared("/*/sql/connections");

	local params = normalize_params(module:get_option("sql", default_params));

	engine = engines[sql.db2uri(params)];

	if not engine then

		module:log("debug", "Creating new engine");

		engine = sql:create_engine(params);

		engines[sql.db2uri(params)] = engine;

	end

	module:provides("storage", driver);

end