-- 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.

--

local format = require "util.format".format;

local setmetatable, rawset, pairs, ipairs, type =

	setmetatable, rawset, pairs, ipairs, type;

local stdout = io.stdout;

local io_open = io.open;

local math_max, rep = math.max, string.rep;

local os_date = os.date;

local getstyle, getstring = require "util.termcolours".getstyle, require "util.termcolours".getstring;

local st = require "util.stanza";

local config = require "core.configmanager";

local logger = require "util.logger";

local have_pposix, pposix = pcall(require, "util.pposix");

have_pposix = have_pposix and pposix._VERSION == "0.4.0";

local _ENV = nil;

-- luacheck: std none

-- The log config used if none specified in the config file (see reload_logging for initialization)

local default_logging;

local default_file_logging;

local default_timestamp = "%b %d %H:%M:%S ";

-- The actual config loggingmanager is using

local logging_config;

local apply_sink_rules;

local log_sink_types = setmetatable({}, { __newindex = function (t, k, v) rawset(t, k, v); apply_sink_rules(k); end; });

local get_levels;

local logging_levels = { "debug", "info", "warn", "error" }

local function id(x) return x end

-- Put a rule into action. Requires that the sink type has already been registered.

-- This function is called automatically when a new sink type is added [see apply_sink_rules()]

local function add_rule(sink_config)

	local sink_maker = log_sink_types[sink_config.to];

	if not sink_maker then

		return; -- No such sink type

	end

	-- Create sink

	local sink = sink_maker(sink_config);

	-- Set sink for all chosen levels

	for level in pairs(get_levels(sink_config.levels or logging_levels)) do

		logger.add_level_sink(level, sink);

	end

end

-- Search for all rules using a particular sink type, and apply

-- them. Called automatically when a new sink type is added to

-- the log_sink_types table.

function apply_sink_rules(sink_type)

	if type(logging_config) == "table" then

		for _, level in ipairs(logging_levels) do

			if type(logging_config[level]) == "string" then

				local value = logging_config[level];

				if sink_type == "file" and not value:match("^%*") then

					add_rule({

						to = sink_type;

						filename = value;

						timestamps = true;

						levels = { min = level };

					});

				elseif value == "*"..sink_type then

					add_rule({

						to = sink_type;

						levels = { min = level };

					});

				end

			end

		end

		for _, sink_config in ipairs(logging_config) do

			if (type(sink_config) == "table" and sink_config.to == sink_type) then

				add_rule(sink_config);

			elseif (type(sink_config) == "string" and sink_config:match("^%*(.+)") == sink_type) then

				add_rule({ levels = { min = "debug" }, to = sink_type });

			end

		end

	elseif type(logging_config) == "string" and (not logging_config:match("^%*")) and sink_type == "file" then

		-- User specified simply a filename, and the "file" sink type

		-- was just added

		for _, sink_config in pairs(default_file_logging) do

			sink_config.filename = logging_config;

			add_rule(sink_config);

			sink_config.filename = nil;

		end

	elseif type(logging_config) == "string" and logging_config:match("^%*(.+)") == sink_type then

		-- Log all levels (debug+) to this sink

		add_rule({ levels = { min = "debug" }, to = sink_type });

	end

end

--- Helper function to get a set of levels given a "criteria" table

function get_levels(criteria, set)

	set = set or {};

	if type(criteria) == "string" then

		set[criteria] = true;

		return set;

	end

	local min, max = criteria.min, criteria.max;

	if min or max then

		local in_range;

		for _, level in ipairs(logging_levels) do

			if min == level then

				set[level] = true;

				in_range = true;

			elseif max == level then

				set[level] = true;

				return set;

			elseif in_range then

				set[level] = true;

			end

		end

	end

	for _, level in ipairs(criteria) do

		set[level] = true;

	end

	return set;

end

-- Initialize config, etc. --

local function reload_logging()

	local old_sink_types = {};

	for name, sink_maker in pairs(log_sink_types) do

		old_sink_types[name] = sink_maker;

		log_sink_types[name] = nil;

	end

	logger.reset();

	local debug_mode = config.get("*", "debug");

	default_logging = { { to = "console" , levels = { min = (debug_mode and "debug") or "info" } } };

	default_file_logging = {

		{ to = "file", levels = { min = (debug_mode and "debug") or "info" }, timestamps = true }

	};

	logging_config = config.get("*", "log") or default_logging;

	for name, sink_maker in pairs(old_sink_types) do

		log_sink_types[name] = sink_maker;

	end

end

--- Definition of built-in logging sinks ---

-- Null sink, must enter log_sink_types *first*

local function log_to_nowhere()

	return function () return false; end;

end

log_sink_types.nowhere = log_to_nowhere;

local function log_to_file(sink_config, logfile)

	logfile = logfile or io_open(sink_config.filename, "a+");

	if not logfile then

		return log_to_nowhere(sink_config);

	end

	local write = logfile.write;

	local timestamps = sink_config.timestamps;

	if timestamps == true or timestamps == nil then

		timestamps = default_timestamp; -- Default format

	elseif timestamps then

		timestamps = timestamps .. " ";

	end

	if sink_config.buffer_mode ~= false then

		logfile:setvbuf(sink_config.buffer_mode or "line");

	end

	-- Column width for "source" (used by stdout and console)

	local sourcewidth = sink_config.source_width;

	local filter = sink_config.filter or id;

	if sourcewidth then

		return function (name, level, message, ...)

			sourcewidth = math_max(#name+2, sourcewidth);

			write(logfile, timestamps and os_date(timestamps) or "", name, rep(" ", sourcewidth-#name), level, "\t", filter(format(message, ...)), "\n");

		end

	else

		return function (name, level, message, ...)

			write(logfile, timestamps and os_date(timestamps) or "", name, "\t", level, "\t", filter(format(message, ...)), "\n");

		end

	end

end

log_sink_types.file = log_to_file;

local function log_to_stdout(sink_config)

	if not sink_config.timestamps then

		sink_config.timestamps = false;

	end

	if sink_config.source_width == nil then

		sink_config.source_width = 20;

	end

	return log_to_file(sink_config, stdout);

end

log_sink_types.stdout = log_to_stdout;

local do_pretty_printing = not have_pposix or pposix.isatty(stdout);

local logstyles, pretty;

if do_pretty_printing then

	logstyles = {};

	logstyles["info"] = getstyle("bold");

	logstyles["warn"] = getstyle("bold", "yellow");

	logstyles["error"] = getstyle("bold", "red");

	pretty = st.pretty_print;

end

local function log_to_console(sink_config)

	-- Really if we don't want pretty colours then just use plain stdout

	-- FIXME refactor to allow console logging with colours on stderr

	if not do_pretty_printing then

		return log_to_stdout(sink_config);

	end

	sink_config.filter = pretty;

	local logstdout = log_to_stdout(sink_config);

	return function (name, level, message, ...)

		local logstyle = logstyles[level];

		if logstyle then

			level = getstring(logstyle, level);

		end

		return logstdout(name, level, message, ...);

	end

end

log_sink_types.console = log_to_console;

if have_pposix then

	local syslog_opened;

	local function log_to_syslog(sink_config) -- luacheck: ignore 212/sink_config

		if not syslog_opened then

			local facility = sink_config.syslog_facility or config.get("*", "syslog_facility");

			pposix.syslog_open(sink_config.syslog_name or "prosody", facility);

			syslog_opened = true;

		end

		local syslog = pposix.syslog_log;

		return function (name, level, message, ...)

			syslog(level, name, format(message, ...));

		end;

	end

	log_sink_types.syslog = log_to_syslog;

end

local function register_sink_type(name, sink_maker)

	local old_sink_maker = log_sink_types[name];

	log_sink_types[name] = sink_maker;

	return old_sink_maker;

end

return {

	reload_logging = reload_logging;

	register_sink_type = register_sink_type;

}