#!/usr/bin/env lua
-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
-- 
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

-- prosody - main executable for Prosody XMPP server

-- Will be modified by configure script if run --

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

if #arg > 0 and arg[1] ~= "--config" then
	print("Unknown command-line option: "..tostring(arg[1]));
	print("Perhaps you meant to use prosodyctl instead?");
	return 1;
end

-- Global 'prosody' object
local prosody = { events = require "util.events".new(); };
_G.prosody = prosody;

-- Check dependencies
local dependencies = require "util.dependencies";

-- Load the config-parsing module
config = require "core.configmanager"

-- -- -- --
-- Define the functions we call during startup, the 
-- actual startup happens right at the end, where these
-- functions get called

function read_config()
	local filenames = {};
	
	local filename;
	if arg[1] == "--config" and arg[2] then
		table.insert(filenames, arg[2]);
		if CFG_CONFIGDIR then
			table.insert(filenames, CFG_CONFIGDIR.."/"..arg[2]);
		end
	elseif os.getenv("PROSODY_CONFIG") then -- Passed by prosodyctl
			table.insert(filenames, os.getenv("PROSODY_CONFIG"));
	else
		for _, format in ipairs(config.parsers()) do
			table.insert(filenames, (CFG_CONFIGDIR or ".").."/prosody.cfg."..format);
		end
	end
	for _,_filename in ipairs(filenames) do
		filename = _filename;
		local file = io.open(filename);
		if file then
			file:close();
			CFG_CONFIGDIR = filename:match("^(.*)[\\/][^\\/]*$");
			break;
		end
	end
	prosody.config_file = filename
	local ok, level, err = config.load(filename);
	if not ok then
		print("\n");
		print("**************************");
		if level == "parser" then
			print("A problem occured while reading the config file "..(CFG_CONFIGDIR or ".").."/prosody.cfg.lua"..":");
			print("");
			local err_line, err_message = tostring(err):match("%[string .-%]:(%d*): (.*)");
			if err:match("chunk has too many syntax levels$") then
				print("An Include statement in a config file is including an already-included");
				print("file and causing an infinite loop. An Include statement in a config file is...");
			else
				print("Error"..(err_line and (" on line "..err_line) or "")..": "..(err_message or tostring(err)));
			end
			print("");
		elseif level == "file" then
			print("Prosody was unable to find the configuration file.");
			print("We looked for: "..(CFG_CONFIGDIR or ".").."/prosody.cfg.lua");
			print("A sample config file is included in the Prosody download called prosody.cfg.lua.dist");
			print("Copy or rename it to prosody.cfg.lua and edit as necessary.");
		end
		print("More help on configuring Prosody can be found at https://prosody.im/doc/configure");
		print("Good luck!");
		print("**************************");
		print("");
		os.exit(1);
	end
end

function check_dependencies()
	if not dependencies.check_dependencies() then
		os.exit(1);
	end
end

function load_libraries()
	-- Load socket framework
	socket = require "socket";
	server = require "net.server"
end	

function init_logging()
	-- Initialize logging
	require "core.loggingmanager"
end

function log_dependency_warnings()
	dependencies.log_warnings();
end

function sanity_check()
	for host, host_config in pairs(config.getconfig()) do
		if host ~= "*"
		and host_config.enabled ~= false
		and not host_config.component_module then
			return;
		end
	end
	log("error", "No enabled VirtualHost entries found in the config file.");
	log("error", "At least one active host is required for Prosody to function. Exiting...");
	os.exit(1);
end

function sandbox_require()
	-- Replace require() with one that doesn't pollute _G, required
	-- for neat sandboxing of modules
	local _realG = _G;
	local _real_require = require;
	local getfenv = getfenv or function (f)
		-- FIXME: This is a hack to replace getfenv() in Lua 5.2
		local name, env = debug.getupvalue(debug.getinfo(f or 1).func, 1);
		if name == "_ENV" then
			return env;
		end
	end
	function require(...)
		local curr_env = getfenv(2);
		local curr_env_mt = getmetatable(curr_env);
		local _realG_mt = getmetatable(_realG);
		if curr_env_mt and curr_env_mt.__index and not curr_env_mt.__newindex and _realG_mt then
			local old_newindex, old_index;
			old_newindex, _realG_mt.__newindex = _realG_mt.__newindex, curr_env;
			old_index, _realG_mt.__index = _realG_mt.__index, function (_G, k)
				return rawget(curr_env, k);
			end;
			local ret = _real_require(...);
			_realG_mt.__newindex = old_newindex;
			_realG_mt.__index = old_index;
			return ret;
		end
		return _real_require(...);
	end
end

function set_function_metatable()
	local mt = {};
	function mt.__index(f, upvalue)
		local i, name, value = 0;
		repeat
			i = i + 1;
			name, value = debug.getupvalue(f, i);
		until name == upvalue or name == nil;
		return value;
	end
	function mt.__newindex(f, upvalue, value)
		local i, name = 0;
		repeat
			i = i + 1;
			name = debug.getupvalue(f, i);
		until name == upvalue or name == nil;
		if name then
			debug.setupvalue(f, i, value);
		end
	end
	function mt.__tostring(f)
		local info = debug.getinfo(f);
		return ("function(%s:%d)"):format(info.short_src:match("[^\\/]*$"), info.linedefined);
	end
	debug.setmetatable(function() end, mt);
end

function init_global_state()
	-- COMPAT: These globals are deprecated
	bare_sessions = {};
	full_sessions = {};
	hosts = {};

	prosody.bare_sessions = bare_sessions;
	prosody.full_sessions = full_sessions;
	prosody.hosts = hosts;
	
	local data_path = config.get("*", "data_path") or CFG_DATADIR or "data";
	local custom_plugin_paths = config.get("*", "plugin_paths");
	if custom_plugin_paths then
		local path_sep = package.config:sub(3,3);
		-- path1;path2;path3;defaultpath...
		CFG_PLUGINDIR = table.concat(custom_plugin_paths, path_sep)..path_sep..(CFG_PLUGINDIR or "plugins");
	end
	prosody.paths = { source = CFG_SOURCEDIR, config = CFG_CONFIGDIR or ".", 
	                  plugins = CFG_PLUGINDIR or "plugins", data = data_path };

	prosody.arg = _G.arg;

	prosody.platform = "unknown";
	if os.getenv("WINDIR") then
		prosody.platform = "windows";
	elseif package.config:sub(1,1) == "/" then
		prosody.platform = "posix";
	end
	
	prosody.installed = nil;
	if CFG_SOURCEDIR and (prosody.platform == "windows" or CFG_SOURCEDIR:match("^/")) then
		prosody.installed = true;
	end
	
	if prosody.installed then
		-- Change working directory to data path.
		require "lfs".chdir(data_path);
	end

	-- Function to reload the config file
	function prosody.reload_config()
		log("info", "Reloading configuration file");
		prosody.events.fire_event("reloading-config");
		local ok, level, err = config.load(prosody.config_file);
		if not ok then
			if level == "parser" then
				log("error", "There was an error parsing the configuration file: %s", tostring(err));
			elseif level == "file" then
				log("error", "Couldn't read the config file when trying to reload: %s", tostring(err));
			end
		end
		return ok, (err and tostring(level)..": "..tostring(err)) or nil;
	end

	-- Function to reopen logfiles
	function prosody.reopen_logfiles()
		log("info", "Re-opening log files");
		prosody.events.fire_event("reopen-log-files");
	end

	-- Function to initiate prosody shutdown
	function prosody.shutdown(reason, code)
		log("info", "Shutting down: %s", reason or "unknown reason");
		prosody.shutdown_reason = reason;
		prosody.shutdown_code = code;
		prosody.events.fire_event("server-stopping", {
			reason = reason;
			code = code;
		});
		server.setquitting(true);
	end
end

function read_version()
	-- Try to determine version
	local version_file = io.open((CFG_SOURCEDIR or ".").."/prosody.version");
	if version_file then
		prosody.version = version_file:read("*a"):gsub("%s*$", "");
		version_file:close();
		if #prosody.version == 12 and prosody.version:match("^[a-f0-9]+$") then
			prosody.version = "hg:"..prosody.version;
		end
	else
		prosody.version = "unknown";
	end
end

function load_secondary_libraries()
	--- Load and initialise core modules
	require "util.import"
	require "util.xmppstream"
	require "core.stanza_router"
	require "core.statsmanager"
	require "core.hostmanager"
	require "core.portmanager"
	require "core.modulemanager"
	require "core.usermanager"
	require "core.rostermanager"
	require "core.sessionmanager"
	package.loaded['core.componentmanager'] = setmetatable({},{__index=function()
		log("warn", "componentmanager is deprecated: %s", debug.traceback():match("\n[^\n]*\n[ \t]*([^\n]*)"));
		return function() end
	end});

	require "net.http"
	
	require "util.array"
	require "util.datetime"
	require "util.iterators"
	require "util.timer"
	require "util.helpers"
	
	pcall(require, "util.signal") -- Not on Windows
	
	-- Commented to protect us from 
	-- the second kind of people
	--[[ 
	pcall(require, "remdebug.engine");
	if remdebug then remdebug.engine.start() end
	]]

	require "util.stanza"
	require "util.jid"
end

function init_data_store()
	require "core.storagemanager";
end

function prepare_to_start()
	log("info", "Prosody is using the %s backend for connection handling", server.get_backend());
	-- Signal to modules that we are ready to start
	prosody.events.fire_event("server-starting");
	prosody.start_time = os.time();
end	

function init_global_protection()
	-- Catch global accesses
	local locked_globals_mt = {
		__index = function (t, k) log("warn", "%s", debug.traceback("Attempt to read a non-existent global '"..tostring(k).."'", 2)); end;
		__newindex = function (t, k, v) error("Attempt to set a global: "..tostring(k).." = "..tostring(v), 2); end;
	};
		
	function prosody.unlock_globals()
		setmetatable(_G, nil);
	end
	
	function prosody.lock_globals()
		setmetatable(_G, locked_globals_mt);
	end

	-- And lock now...
	prosody.lock_globals();
end

function loop()
	-- Error handler for errors that make it this far
	local function catch_uncaught_error(err)
		if type(err) == "string" and err:match("interrupted!$") then
			return "quitting";
		end
		
		log("error", "Top-level error, please report:\n%s", tostring(err));
		local traceback = debug.traceback("", 2);
		if traceback then
			log("error", "%s", traceback);
		end
		
		prosody.events.fire_event("very-bad-error", {error = err, traceback = traceback});
	end
	
	local sleep = require"socket".sleep;

	while select(2, xpcall(server.loop, catch_uncaught_error)) ~= "quitting" do
		sleep(0.2);
	end
end

function cleanup()
	log("info", "Shutdown status: Cleaning up");
	prosody.events.fire_event("server-cleanup");
end

-- Are you ready? :)
-- These actions are in a strict order, as many depend on
-- previous steps to have already been performed
read_config();
init_logging();
sanity_check();
sandbox_require();
set_function_metatable();
check_dependencies();
load_libraries();
init_global_state();
read_version();
log("info", "Hello and welcome to Prosody version %s", prosody.version);
log_dependency_warnings();
load_secondary_libraries();
init_data_store();
init_global_protection();
prepare_to_start();

prosody.events.fire_event("server-started");

loop();

log("info", "Shutting down...");
cleanup();
prosody.events.fire_event("server-stopped");
log("info", "Shutdown complete");

os.exit(prosody.shutdown_code)