#!/usr/bin/env lua

CFG_SOURCEDIR=CFG_SOURCEDIR or os.getenv("PROSODY_SRCDIR");

CFG_CONFIGDIR=CFG_CONFIGDIR or os.getenv("PROSODY_CFGDIR");

CFG_PLUGINDIR=CFG_PLUGINDIR or os.getenv("PROSODY_PLUGINDIR");

CFG_DATADIR=CFG_DATADIR or os.getenv("PROSODY_DATADIR");

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

local function is_relative(path)

	local path_sep = package.config:sub(1,1);

        return ((path_sep == "/" and path:sub(1,1) ~= "/")

	or (path_sep == "\\" and (path:sub(1,1) ~= "/" and path:sub(2,3) ~= ":\\")))

end

-- Tell Lua where to find our libraries

if CFG_SOURCEDIR then

	local function filter_relative_paths(path)

		if is_relative(path) then return ""; end

	end

	local function sanitise_paths(paths)

		return (paths:gsub("[^;]+;?", filter_relative_paths):gsub(";;+", ";"));

	end

	package.path = sanitise_paths(CFG_SOURCEDIR.."/?.lua;"..package.path);

	package.cpath = sanitise_paths(CFG_SOURCEDIR.."/?.so;"..package.cpath);

end

-- Substitute ~ with path to home directory in data path

if CFG_DATADIR then

	if os.getenv("HOME") then

		CFG_DATADIR = CFG_DATADIR:gsub("^~", os.getenv("HOME"));

	end

end

local default_config = (CFG_CONFIGDIR or ".").."/migrator.cfg.lua";

local function usage()

	print("Usage: " .. arg[0] .. " [OPTIONS] FROM_STORE TO_STORE");

	print("  --config FILE         Specify config file")

	print("  --keep-going          Keep going in case of errors");

	print("  -v, --verbose         Increase log-level");

	print("");

	print("If no stores are specified, 'input' and 'output' are used.");

end

if not pcall(require, "prosody.loader") then

	pcall(require, "loader");

end

local startup = require "prosody.util.startup";

do

	startup.parse_args({

		short_params = { v = "verbose", h = "help", ["?"] = "help" };

		value_params = { config = true };

	});

	startup.init_global_state();

	prosody.process_type = "migrator";

	if prosody.opts.help then

		usage();

		os.exit(0);

	end

	startup.force_console_logging();

	startup.init_logging();

	startup.init_gc();

	startup.init_errors();

	startup.setup_plugindir();

	startup.setup_plugin_install_path();

	startup.setup_datadir();

	startup.chdir();

	startup.read_version();

	startup.switch_user();

	startup.check_dependencies();

	startup.log_startup_warnings();

	prosody.config_loaded = true;

	startup.load_libraries();

	startup.init_http_client();

	prosody.core_post_stanza = function ()

		-- silence assert in core.moduleapi

		error("Attempt to send stanzas from inside migrator.", 0);

	end

end

-- Command-line parsing

local options = prosody.opts;

local envloadfile = require "prosody.util.envload".envloadfile;

local config_file = options.config or default_config;

local from_store = arg[1] or "input";

local to_store = arg[2] or "output";

config = {};

local config_env = setmetatable({}, { __index = function(t, k) return function(tbl) config[k] = tbl; end; end });

local config_chunk, err = envloadfile(config_file, config_env);

if not config_chunk then

	print("There was an error loading the config file, check that the file exists");

	print("and that the syntax is correct:");

	print("", err);

	os.exit(1);

end

config_chunk();

local have_err;

if #arg > 0 and #arg ~= 2 then

	have_err = true;

	print("Error: Incorrect number of parameters supplied.");

end

if not config[from_store] then

	have_err = true;

	print("Error: Input store '"..from_store.."' not found in the config file.");

end

if not config[to_store] then

	have_err = true;

	print("Error: Output store '"..to_store.."' not found in the config file.");

end

for store, conf in pairs(config) do -- COMPAT

	if conf.type == "prosody_files" then

		conf.type = "internal";

	elseif conf.type == "prosody_sql" then

		conf.type = "sql";

	end

end

if have_err then

	print("");

	usage();

	print("");

	print("The available stores in your migrator config are:");

	print("");

	for store in pairs(config) do

		print("", store);

	end

	print("");

	os.exit(1);

end

local async = require "prosody.util.async";

local server = require "prosody.net.server";

local watchers = {

	error = function (_, err)

		error(err);

	end;

	waiting = function ()

		server.loop();

	end;

};

local cm = require "prosody.core.configmanager";

local hm = require "prosody.core.hostmanager";

local sm = require "prosody.core.storagemanager";

local um = require "prosody.core.usermanager";

local function users(store, host)

	if store.users then

		log("debug", "Using store user iterator")

		return store:users();

	else

		log("debug", "Using usermanager user iterator")

		return um.users(host);

	end

end

local function prepare_config(host, conf)

	if conf.type == "internal" then

		sm.olddm.set_data_path(conf.path or prosody.paths.data);

	elseif conf.type == "sql" then

		cm.set(host, "sql", conf);

	end

	if type(conf.config) == "table" then

		for option, value in pairs(conf.config) do

			cm.set(host, option, value);

		end

	end

end

local function get_driver(host, conf)

	prepare_config(host, conf);

	return assert(sm.load_driver(host, conf.type));

end

local migrate_once = {

	keyval = function(origin, destination, user)

		local data, err = origin:get(user);

		assert(not err, err);

		assert(destination:set(user, data));

	end;

	archive = function(origin, destination, user)

		local iter, err = origin:find(user);

		assert(iter, err);

		for id, item, when, with in iter do

			assert(destination:append(user, id, item, when, with));

		end

	end;

}

migrate_once.pubsub = function(origin, destination, user, prefix, input_driver, output_driver)

	if not user and prefix == "pubsub_" then return end

	local data, err = origin:get(user);

	assert(not err, err);

	if not data then return end

	assert(destination:set(user, data));

	if prefix == "pubsub_" then user = nil end

	for node in pairs(data) do

		local pep_origin = assert(input_driver:open(prefix .. node, "archive"));

		local pep_destination = assert(output_driver:open(prefix .. node, "archive"));

		migrate_once.archive(pep_origin, pep_destination, user);

	end

end

if options["keep-going"] then

	local xpcall = require "prosody.util.xpcall".xpcall;

	for t, f in pairs(migrate_once) do

		migrate_once[t] = function (origin, destination, user, ...)

			local function log_err(err)

				if user then

					log("error", "Error migrating data for user %q: %s", user, err);

				else

					log("error", "Error migrating data for host: %s", err);

				end

				log("debug", "%s", debug.traceback(nil, 2));

			end

			xpcall(f, log_err, origin, destination, user, ...);

		end

	end

end

local migration_runner = async.runner(function (job)

	for host, stores in pairs(job.input.hosts) do

		prosody.hosts[host] = startup.make_host(host);

		sm.initialize_host(host);

		um.initialize_host(host);

		local input_driver = get_driver(host, job.input);

		local output_driver = get_driver(host, job.output);

		for _, store in ipairs(stores) do

			local p, typ = store:match("()%-(%w+)$");

			if typ then store = store:sub(1, p-1); else typ = "keyval"; end

			log("info", "Migrating host %s store %s (%s)", host, store, typ);

			local migrate = assert(migrate_once[typ], "Unknown store type: "..typ);

			local prefix = store .. "_";

			if typ == "pubsub" then typ = "keyval"; end

			if store == "pubsub_nodes" then prefix = "pubsub_"; end

			local origin = assert(input_driver:open(store, typ));

			local destination = assert(output_driver:open(store, typ));

			migrate(origin, destination, nil, prefix, input_driver, output_driver); -- host data

			for user in users(origin, host) do

				log("info", "Migrating user %s@%s store %s (%s)", user, host, store, typ);

				migrate(origin, destination, user, prefix, input_driver, output_driver);

			end

		end

	end

end, watchers);

io.stderr:write("Migrating...\n");

migration_runner:run({ input = config[from_store], output = config[to_store] });

io.stderr:write("Done!\n");