#include "tpluginmanager.h"
#include "tsystem.h"
#include "tconvert.h"
#include "tlogger.h"

#ifdef _WIN32
#include <windows.h>
#else

// QUALE DI QUESTI SERVE VERAMENTE??
#include <grp.h>
#include <utime.h>
#include <sys/param.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/timeb.h> // for ftime
#include <stdio.h>
#include <unistd.h>
#include <dirent.h>
#include <sys/dir.h>
#include <sys/param.h> // for getfsstat
#ifdef MACOSX
#include <sys/ucred.h>
#endif
#include <sys/mount.h>
#include <pwd.h>
#include <dlfcn.h>
#endif

//-----------------------------------------------------------------------------

class TPluginManager::Plugin
{
public:
#ifdef _WIN32
	typedef HINSTANCE Handle;
#else
	typedef void *Handle;
#endif

private:
	Handle m_handle;
	TPluginInfo m_info;

public:
	Plugin(Handle handle)
		: m_handle(handle)
	{
	}

	Handle getHandle() const { return m_handle; }
	const TPluginInfo &getInfo() const { return m_info; }
	void setInfo(const TPluginInfo &info) { m_info = info; }
	std::string getName() const { return m_info.getName(); }
};

//-----------------------------------------------------------------------------

typedef const TPluginInfo *TnzLibMainProcType();

//--------------------------------------------------------------

namespace
{
const char *TnzLibMainProcName = "TLibMain";
#if !defined(_WIN32)
const char *TnzLibMainProcName2 = "_TLibMain";
#endif
}

//=============================================================================

TPluginManager::TPluginManager()
{
	m_ignoreList.insert("tnzimagevector");
}

//-----------------------------------------------------------------------------

TPluginManager::~TPluginManager()
{
	//   try { unloadPlugins(); } catch(...) {}
}

//-----------------------------------------------------------------------------

TPluginManager *TPluginManager::instance()
{
	static TPluginManager _instance;
	return &_instance;
}

//-----------------------------------------------------------------------------

bool TPluginManager::isIgnored(std::string name) const
{
	return m_ignoreList.count(toLower(name)) > 0;
}

//-----------------------------------------------------------------------------

void TPluginManager::unloadPlugins()
{
	for (PluginTable::iterator it = m_pluginTable.begin();
		 it != m_pluginTable.end(); ++it) {
		Plugin::Handle handle = (*it)->getHandle();
#ifndef LINUX
#ifdef _WIN32
		FreeLibrary(handle);
#else
		dlclose(handle);
#endif
#endif
		delete (*it);
	}
	m_pluginTable.clear();
}

//--------------------------------------------------------------

void TPluginManager::loadPlugin(const TFilePath &fp)
{
	if ((int)m_loadedPlugins.count(fp) > 0) {
		TLogger::debug() << "Already loaded " << fp;
		return;
	}
	std::string name = fp.getName();
	if (isIgnored(name)) {
		TLogger::debug() << "Ignored " << fp;
		return;
	}

	TLogger::debug() << "Loading " << fp;
#ifdef _WIN32
	Plugin::Handle handle = LoadLibraryW(fp.getWideString().c_str());
#else
	Plugin::Handle handle = dlopen(::to_string(fp).c_str(), RTLD_NOW); // RTLD_LAZY
#endif
	if (!handle) {
		// non riesce a caricare la libreria;
		TLogger::warning() << "Unable to load " << fp;
#ifdef _WIN32
		std::wstring getFormattedMessage(DWORD lastError);
		TLogger::warning() << ::to_string(getFormattedMessage(GetLastError()));
#else
		TLogger::warning() << dlerror();
#endif
	} else {
		m_loadedPlugins.insert(fp);
		Plugin *plugin = new Plugin(handle);
		m_pluginTable.push_back(plugin);
		//cout << "loaded" << endl;
		TnzLibMainProcType *tnzLibMain = 0;
#ifdef _WIN32
		tnzLibMain = (TnzLibMainProcType *)
			GetProcAddress(handle, TnzLibMainProcName);
#else
		tnzLibMain = (TnzLibMainProcType *)
			dlsym(handle, TnzLibMainProcName);
		if (!tnzLibMain) //provo _ come prefisso
			tnzLibMain = (TnzLibMainProcType *)dlsym(handle, TnzLibMainProcName2);
#endif

		if (!tnzLibMain) {
			// La libreria non esporta TLibMain;
			TLogger::warning() << "Corrupted " << fp;

#ifdef _WIN32
			FreeLibrary(handle);
#else
			dlclose(handle);
#endif
		} else {
			const TPluginInfo *info = tnzLibMain();
			if (info)
				plugin->setInfo(*info);
		}
	}
}

//--------------------------------------------------------------

void TPluginManager::loadPlugins(const TFilePath &dir)
{
#if defined(_WIN32)
	const std::string extension = "dll";
#elif defined(LINUX) || defined(__sgi)
	const std::string extension = "so";
#elif defined(MACOSX)
	const std::string extension = "dylib";
#endif

	TFilePathSet dirContent = TSystem::readDirectory(dir, false);
	if (dirContent.empty())
		return;

	for (TFilePathSet::iterator it = dirContent.begin();
		 it != dirContent.end(); it++) {
		TFilePath fp = *it;
		if (fp.getType() != extension)
			continue;
		std::wstring fullpath = fp.getWideString();

#ifdef _WIN32

		bool isDebugLibrary = (fullpath.find(L".d.") == fullpath.size() - (extension.size() + 3));

#ifdef _DEBUG
		if (!isDebugLibrary)
#else
		if (isDebugLibrary)
#endif
			continue;

#endif

		try {
			loadPlugin(fp);
		} catch (...) {
			TLogger::warning() << "unexpected error loading " << fp;
		}
	}
}

//--------------------------------------------------------------

void TPluginManager::loadStandardPlugins()
{

	TFilePath pluginsDir = TSystem::getDllDir() + "plugins";

	//loadPlugins(pluginsDir + "io");
	loadPlugins(pluginsDir + "fx");
}

//--------------------------------------------------------------

void TPluginManager::setIgnoredList(const std::set<std::string> &names)
{
	m_ignoreList.clear();
	for (std::set<std::string>::const_iterator it = names.begin(); it != names.end(); ++it)
		m_ignoreList.insert(toLower(*it));
}