/*
 * This file is a part of Winix
 * and is distributed under the 2-Clause BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2008-2022, Tomasz Sowa
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 */
 
#include <dlfcn.h>
#include <string.h>
#include "plugin.h"
#include "misc.h"
#include "system.h"
#include "sessionmanager.h"
#include "functions/functions.h"
#include "templates/templates.h"
#include "winixrequest.h"



namespace Winix
{


void Plugin::UnloadPlugins()
{
size_t i;
	
	slots.clear();

	for(i=0 ; i<plugins.size() ; ++i)
		dlclose(plugins[i].handle);
	
	plugins.clear();
}


Plugin::Plugin()
{
	current_plugin  = -1;

	db              = nullptr;
	cur             = nullptr;
	system          = nullptr;
	functions       = nullptr;
	templates       = nullptr;
	session_manager = nullptr;
	winix_request   = nullptr;

	plugin = this;
}
	

Plugin::~Plugin()
{
	UnloadPlugins();	
}


void Plugin::SetDb(Db * pdb)
{
	db = pdb;
}


void Plugin::SetSystem(System * psystem)
{
	system = psystem;
}


void Plugin::SetCur(Cur * cur)
{
	this->cur = cur;
}


void Plugin::SetFunctions(Functions * pfunctions)
{
	functions = pfunctions;
}


void Plugin::SetTemplates(Templates * ptemplates)
{
	templates = ptemplates;
}


void Plugin::SetSessionManager(SessionManager * psession_manager)
{
	session_manager = psession_manager;
}


void Plugin::SetWinixRequest(WinixRequest * winix_request)
{
	this->winix_request = winix_request;
}



void Plugin::Lock()
{
	if( synchro )
		synchro->Lock();
}


void Plugin::Unlock()
{
	if( synchro )
		synchro->Unlock();
}




bool Plugin::SetDependencyForPluginInfo(morm::ModelConnector * pmodel_connector, Log * plog, Cur * pcur, PluginInfo & info)
{
	// for safety we call a plugin function only when all our pointers are not null
	bool res = (pmodel_connector && plog && pcur && db && config && system && functions && templates && synchro && session_manager && winix_request);

	if( !res )
	{
		log << log1 << "Plugin: cannot call a function - some of the winix pointers are null" << logend;
	}

	info.db        = db;
	info.config    = config;
	info.cur       = pcur;
	info.system    = system;
	info.functions = functions;
	info.templates = templates;
	info.synchro   = synchro;
	info.session_manager = session_manager;
	info.plugin	   = this;
	info.model_connector = pmodel_connector;;

	info.log.set_log_buffer(plog->get_log_buffer());
	info.log.set_file_log(plog->get_file_log());

	return res;
}



void Plugin::LoadPlugins(const std::wstring & plugins_dir, const std::vector<std::wstring> & plugins)
{
	for(size_t i=0 ; i<plugins.size() ; ++i)
	{
		if( !plugins[i].empty() && plugins[i][0] == '/' )
		{
			LoadPlugin(plugins[i]);
		}
		else
		{
			temp_path = plugins_dir;
			temp_path += '/';
			temp_path += plugins[i];
			LoadPlugin(temp_path);
		}
	}
}




// we don't have to use Lock() here because plugins are read
// before threads are started
void * Plugin::LoadInitFun(const wchar_t * filename, Fun1 & fun_init)
{
char file[WINIX_OS_PATH_SIZE];

	if( !wide_to_utf8(filename, file, WINIX_OS_PATH_SIZE) )
		return 0;

	void * p = dlopen(file, RTLD_NOW | RTLD_LOCAL);

	if( !p )
	{
		log << log1 << "Plugin: cannot load a plugin: \"" << filename << "\"" << logend;
		log << log1 << "Plugin: dlerror: " << dlerror() << logend;
		return 0;
	}
	
	fun_init = (Fun1)dlsym(p, "Init");
	
	if( !fun_init )
	{
		log << log1 << "Plugin: cannot load a plugin: " << filename
			<< " (there is no Init() function)" << logend;

		dlclose(p);
		return 0;
	}

	log << log2 << "Plugin: plugin loaded"
		<< ", file: " << filename 
		<< ", index: " << plugins.size() << logend;

return p;
}



void Plugin::LoadPlugin(const wchar_t * filename)
{
Fun1 fun_init;
void * plugin_handle;
int old_current_plugin;
PluginInfo info;

	if( !SetDependencyForPluginInfo(model_connector, &log, cur, info) )
		return;

	if( !(plugin_handle = LoadInitFun(filename, fun_init)) )
		return;

	info.Clear();
	old_current_plugin = current_plugin;
	current_plugin     = (int)plugins.size();
	info.plugin_id     = current_plugin;

	/*
	 * WARNING:
	 * all pointers from Cur are null pointers here
	 */
	fun_init(info);

	PluginsItem item;
	item.handle = plugin_handle;
	item.plugin_name = reinterpret_cast<const wchar_t *>(info.p1);

	plugins.push_back(item);

	current_plugin = old_current_plugin;
}


void Plugin::LoadPlugin(const std::wstring & filename)
{
	LoadPlugin(filename.c_str());
}



bool Plugin::HasPlugin(const wchar_t * name)
{
	if( *name == 0 )
		return false;

	for(size_t i=0 ; i<plugins.size() ; ++i)
	{
		if( plugins[i].plugin_name && Equal(plugins[i].plugin_name, name) )
			return true;
	}

return false;
}



bool Plugin::HasPlugin(const std::wstring & name)
{
	return HasPlugin(name.c_str());
}


bool Plugin::HasMessage(int message)
{
	return (slots.find(message) != slots.end());
}


void Plugin::Call(morm::ModelConnector * model_connector, Log * plog, Cur * cur, int message, Slots::iterator & slot, PluginInfo & info)
{
	if( !SetDependencyForPluginInfo(model_connector, plog, cur, info) )
		return;

	current_plugin = slot->second.index;
	info.plugin_id = current_plugin;

	if( current_plugin != -1 && cur->session && !cur->session->is_temporary_session() )
		info.plugin_data_base = cur->session->plugin_data.Get(current_plugin);
	else
		info.plugin_data_base = nullptr;

	if( !slot->second.is_running )
	{
		if( config->log_plugin_call )
		{
			log << log1 << "Plugin: calling plugin id: " << slot->second.index << ", message: " << message << logend;
		}

		slot->second.is_running = true;

		if( slot->second.fun1 )
			slot->second.fun1(info);

		if( slot->second.fun2 )
			slot->second.fun2();

		slot->second.is_running = false;

		if( config->log_plugin_call )
		{
			log << log1 << "Plugin: returning from plugin id: " << slot->second.index << ", message: " << message
				<< ", result: " << (info.res? "true" : "false") << logend;
		}

	}
	else
	{
		log << log1 << "Plugin: id: " << slot->second.index
			<< ", message: " << message
			<< ", recurrences are not allowed" << logend;
	}
}





PluginRes Plugin::Call(morm::ModelConnector * model_connector, Log * plog, Cur * cur, int message, void * p1, void * p2, long l1, long l2)
{
	PluginRes res;
	int old_current_plugin = current_plugin;
	PluginInfo info;
	Cur local_cur;

	if( !cur )
		cur = &local_cur;

	Slots::iterator i = slots.lower_bound(message);

	for( ; i!=slots.end() && i->first==message ; ++i )
	{
		info.Clear();
		info.p1 = p1;
		info.p2 = p2;
		info.l1 = l1;
		info.l2 = l2;

		Call(model_connector, plog, cur, message, i, info);

		if( info.res )
			++res.res_true;
		else
			++res.res_false;
	}

	current_plugin = old_current_plugin;

	return res;
}



PluginRes Plugin::Call(morm::ModelConnector * model_connector, Log * plog, Session * session, Request * request, Mount * mount, int message, void * p1, void * p2, long l1, long l2)
{
	Cur local_cur;

	local_cur.session = session;
	local_cur.request = request;
	local_cur.mount = mount;

	return Call(model_connector, plog, &local_cur, message, p1, p2, l1, l2);
}



PluginRes Plugin::Call(int message)
{
	return Call(model_connector, &log, cur, message, 0, 0, 0, 0);
}


PluginRes Plugin::Call(int message, void * p1_)
{
	return Call(model_connector, &log, cur, message, p1_, 0, 0, 0);
}


PluginRes Plugin::Call(int message, void * p1_, void * p2_)
{
	return Call(model_connector, &log, cur, message, p1_, p2_, 0, 0);
}


PluginRes Plugin::Call(int message, long l1_)
{
	return Call(model_connector, &log, cur, message, 0, 0, l1_, 0);
}


PluginRes Plugin::Call(int message, long l1_, long l2_)
{
	return Call(model_connector, &log, cur, message, 0, 0, l1_, l2_);
}


PluginRes Plugin::Call(int message, void * p1_, long l1_)
{
	return Call(model_connector, &log, cur, message, p1_, 0, l1_, 0);
}


PluginRes Plugin::Call(int message, void * p1_, long l1_, long l2_)
{
	return Call(model_connector, &log, cur, message, p1_, 0, l1_, l2_);
}


PluginRes Plugin::Call(int message, void * p1_, void * p2_, long l1_)
{
	return Call(model_connector, &log, cur, message, p1_, p2_, l1_, 0);
}



size_t Plugin::Size()
{
	return plugins.size();
}


/*
       !! IMPROVE ME
       Assign() can work only if other threads are not started
       we can add some barrier/flag so when other threads starts
       then we cannot use Assign() method
*/
void Plugin::Assign(int message, Fun1 fun1)
{
Slot s;

	if( current_plugin == -1 )
		return;

	s.fun1  = fun1;
	s.index = current_plugin;

	slots.insert( std::make_pair(message, s) );
	log << log3 << "Plugin: added function for message: " << message << ", plugin index: " << s.index << logend;
}


void Plugin::Assign(int message, Fun2 fun2)
{
Slot s;

	if( current_plugin == -1 )
		return;

	s.fun2  = fun2;
	s.index = current_plugin;

	slots.insert( std::make_pair(message, s) );
	log << log3 << "Plugin: added function for message: " << message << ", plugin index: " << s.index << logend;
}


const Plugin::Plugins * Plugin::GetPlugins()
{
	return &plugins;
}










} // namespace Winix