-- mod_inotify_reload

-- Reloads modules when their files change

-- Depends on linotify: https://github.com/hoelzro/linotify

module:set_global();

local inotify = require "inotify";

local modulemanager = require "core.modulemanager";

local inh = inotify.init();

local watches = {};

local watch_ids = {};

-- Fake socket object around inotify

local inh_conn = {

	getfd = function () return inh:fileno(); end;

	dirty = function (self) return false; end;

	settimeout = function () end;

	send = function (_, d) return #d, 0; end;

	close = function () end;

	receive = function ()

		local events = inh:read();

		for _, event in ipairs(events) do

			local mod = watches[watch_ids[event.wd]];

			if mod then

				local host, name = mod.host, mod.name;

				module:log("debug", "Reloading changed module mod_%s on %s", name, host);

				modulemanager.reload(host, name);

			else

				module:log("warn", "no watch for %d", event.wd);

			end

		end

		return "";

	end

};

require "net.server".wrapclient(inh_conn, "inotify", inh:fileno(), {

	onincoming = function () end, ondisconnect = function () end

}, "*a");

function watch_module(name, host, path)

	local id, err = inh:addwatch(path, inotify.IN_CLOSE_WRITE);

	if not id then return nil, err; end

	local k = host.."\0"..name;

	watches[k] = { id = id, path = path, name = name, host = host };

	watch_ids[id] = k;

	module:log("debug", "Watching %s:%s with id %d", name, host, id);

	return true;

end

function unwatch_module(name, host)

	local k = host.."\0"..name;

	if not watches[k] then

		module:log("warn", "Not watching %s:%s", name, host);

		return nil, "not-watching";

	end

	local id = watches[k].id;

	local ok, err = inh:rmwatch(id);

	module:log("info", "Removed watch %d", id);

	watches[k] = nil;

	watch_ids[id] = nil;

	return ok, err;

end

function module_loaded(event)

	local host, name = event.host, event.module;

	local path = modulemanager.get_module(host, name).module.path;

	if not path then

		module:log("warn", "Couldn't watch mod_%s, no path", name);

		return;

	end

	if watch_module(name, host, path) then

		module:log("debug", "Watching mod_%s", name);

	end

end

function module_unloaded(event)

	unwatch_module(event.module, event.host);

end

function module.add_host(module)

	module:hook("module-loaded", module_loaded);

	module:hook("module-unloaded", module_unloaded);

end

module:hook("module-loaded", module_loaded);

module:hook("module-unloaded", module_unloaded);