-- Prosody IM

-- Copyright (C) 2008-2012 Matthew Wild

-- Copyright (C) 2008-2012 Waqas Hussain

-- 

-- This project is MIT/X11 licensed. Please see the

-- COPYING file in the source package for more information.

--

local config = require "core.configmanager";

local modulemanager = require "modulemanager";

local array = require "util.array";

local set = require "util.set";

local logger = require "util.logger";

local pluginloader = require "util.pluginloader";

local multitable_new = require "util.multitable".new;

local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;

local error, setmetatable, setfenv, type = error, setmetatable, setfenv, type;

local ipairs, pairs, select, unpack = ipairs, pairs, select, unpack;

local tonumber, tostring = tonumber, tostring;

local prosody = prosody;

local hosts = prosody.hosts;

local core_post_stanza = prosody.core_post_stanza;

-- Registry of shared module data

local shared_data = setmetatable({}, { __mode = "v" });

local NULL = {};

local api = {};

-- Returns the name of the current module

function api:get_name()

	return self.name;

end

-- Returns the host that the current module is serving

function api:get_host()

	return self.host;

end

function api:get_host_type()

	return hosts[self.host].type;

end

function api:set_global()

	self.host = "*";

	-- Update the logger

	local _log = logger.init("mod_"..self.name);

	self.log = function (self, ...) return _log(...); end;

	self._log = _log;

	self.global = true;

end

function api:add_feature(xmlns)

	self:add_item("feature", xmlns);

end

function api:add_identity(category, type, name)

	self:add_item("identity", {category = category, type = type, name = name});

end

function api:add_extension(data)

	self:add_item("extension", data);

end

function api:fire_event(...)

	return (hosts[self.host] or prosody).events.fire_event(...);

end

function api:hook_object_event(object, event, handler, priority)

	self.event_handlers[handler] = { name = event, priority = priority, object = object };

	return object.add_handler(event, handler, priority);

end

function api:hook(event, handler, priority)

	return self:hook_object_event((hosts[self.host] or prosody).events, event, handler, priority);

end

function api:hook_global(event, handler, priority)

	return self:hook_object_event(prosody.events, event, handler, priority);

end

function api:hook_stanza(xmlns, name, handler, priority)

	if not handler and type(name) == "function" then

		-- If only 2 options then they specified no xmlns

		xmlns, name, handler, priority = nil, xmlns, name, handler;

	elseif not (handler and name) then

		self:log("warn", "Error: Insufficient parameters to module:hook_stanza()");

		return;

	end

	return self:hook("stanza/"..(xmlns and (xmlns..":") or "")..name, function (data) return handler(data.origin, data.stanza, data); end, priority);

end

function api:require(lib)

	local f, n = pluginloader.load_code(self.name, lib..".lib.lua");

	if not f then

		f, n = pluginloader.load_code(lib, lib..".lib.lua");

	end

	if not f then error("Failed to load plugin library '"..lib.."', error: "..n); end -- FIXME better error message

	setfenv(f, self.environment);

	return f();

end

function api:depends(name)

	if not self.dependencies then

		self.dependencies = {};

		self:hook("module-reloaded", function (event)

			if self.dependencies[event.module] then

				self:log("info", "Auto-reloading due to reload of %s:%s", event.host, event.module);

				modulemanager.reload(self.host, self.name);

				return;

			end

		end);

		self:hook("module-unloaded", function (event)

			if self.dependencies[event.module] then

				self:log("info", "Auto-unloading due to unload of %s:%s", event.host, event.module);

				modulemanager.unload(self.host, self.name);

			end

		end);

	end

	local mod = modulemanager.get_module(self.host, name) or modulemanager.get_module("*", name);

	if mod and mod.module.host == "*" and modulemanager.module_has_method(mod, "add_host") then

		mod = nil; -- This is a shared module, so we still want to load it on our host

	end

	if not mod then

		local err;

		mod, err = modulemanager.load(self.host, name);

		if not mod then

			return error(("Unable to load required module, mod_%s: %s"):format(name, ((err or "unknown error"):gsub("%-", " ")) ));

		end

	end

	self.dependencies[name] = true;

	return mod;

end

-- Returns one or more shared tables at the specified virtual paths

-- Intentionally does not allow the table at a path to be _set_, it

-- is auto-created if it does not exist.

function api:shared(...)

	if not self.shared_data then self.shared_data = {}; end

	local paths = { n = select("#", ...), ... };

	local data_array = {};

	local default_path_components = { self.host, self.name };

	for i = 1, paths.n do

		local path = paths[i];

		if path:sub(1,1) ~= "/" then -- Prepend default components

			local n_components = select(2, path:gsub("/", "%1"));

			path = (n_components<#default_path_components and "/" or "")..t_concat(default_path_components, "/", 1, #default_path_components-n_components).."/"..path;

		end

		local shared = shared_data[path];

		if not shared then

			shared = {};

			shared_data[path] = shared;

		end

		t_insert(data_array, shared);

		self.shared_data[path] = shared;

	end

	return unpack(data_array);

end

function api:get_option(name, default_value)

	local value = config.get(self.host, self.name, name);

	if value == nil then

		value = config.get(self.host, "core", name);

		if value == nil then

			value = default_value;

		end

	end

	return value;

end

function api:get_option_string(name, default_value)

	local value = self:get_option(name, default_value);

	if type(value) == "table" then

		if #value > 1 then

			self:log("error", "Config option '%s' does not take a list, using just the first item", name);

		end

		value = value[1];

	end

	if value == nil then

		return nil;

	end

	return tostring(value);

end

function api:get_option_number(name, ...)

	local value = self:get_option(name, ...);

	if type(value) == "table" then

		if #value > 1 then

			self:log("error", "Config option '%s' does not take a list, using just the first item", name);

		end

		value = value[1];

	end

	local ret = tonumber(value);

	if value ~= nil and ret == nil then

		self:log("error", "Config option '%s' not understood, expecting a number", name);

	end

	return ret;

end

function api:get_option_boolean(name, ...)

	local value = self:get_option(name, ...);

	if type(value) == "table" then

		if #value > 1 then

			self:log("error", "Config option '%s' does not take a list, using just the first item", name);

		end

		value = value[1];

	end

	if value == nil then

		return nil;

	end

	local ret = value == true or value == "true" or value == 1 or nil;

	if ret == nil then

		ret = (value == false or value == "false" or value == 0);

		if ret then

			ret = false;

		else

			ret = nil;

		end

	end

	if ret == nil then

		self:log("error", "Config option '%s' not understood, expecting true/false", name);

	end

	return ret;

end

function api:get_option_array(name, ...)

	local value = self:get_option(name, ...);

	if value == nil then

		return nil;

	end

	if type(value) ~= "table" then

		return array{ value }; -- Assume any non-list is a single-item list

	end

	return array():append(value); -- Clone

end

function api:get_option_set(name, ...)

	local value = self:get_option_array(name, ...);

	if value == nil then

		return nil;

	end

	return set.new(value);

end

local module_items = multitable_new();

function api:add_item(key, value)

	self.items = self.items or {};

	self.items[key] = self.items[key] or {};

	t_insert(self.items[key], value);

	self:fire_event("item-added/"..key, {source = self, item = value});

end

function api:remove_item(key, value)

	local t = self.items and self.items[key] or NULL;

	for i = #t,1,-1 do

		if t[i] == value then

			t_remove(self.items[key], i);

			self:fire_event("item-removed/"..key, {source = self, item = value});

			return value;

		end

	end

end

function api:get_host_items(key)

	local result = {};

	for mod_name, module in pairs(modulemanager.get_modules(self.host)) do

		module = module.module;

		if module.items then

			for _, item in ipairs(module.items[key] or NULL) do

				t_insert(result, item);

			end

		end

	end

	for mod_name, module in pairs(modulemanager.get_modules("*")) do

		module = module.module;

		if module.items then

			for _, item in ipairs(module.items[key] or NULL) do

				t_insert(result, item);

			end

		end

	end

	return result;

end

function api:handle_items(type, added_cb, removed_cb, existing)

	self:hook("item-added/"..type, added_cb);

	self:hook("item-removed/"..type, removed_cb);

	if existing ~= false then

		for _, item in ipairs(self:get_host_items(type)) do

			added_cb({ item = item });

		end

	end

end

function api:provides(name, item)

	if not item then item = self.environment; end

	if not item.name then

		local item_name = self.name;

		-- Strip a provider prefix to find the item name

		-- (e.g. "auth_foo" -> "foo" for an auth provider)

		if item_name:find(name.."_", 1, true) == 1 then

			item_name = item_name:sub(#name+2);

		end

		item.name = item_name;

	end

	self:add_item(name.."-provider", item);

end

function api:send(stanza)

	return core_post_stanza(hosts[self.host], stanza);

end

return api;