#include "ExtensionSys.h"

#include "LibrarySys.h"

#include "ShareSys.h"

#include "CLogger.h"

#include "sourcemm_api.h"

CExtensionManager g_Extensions;

IdentityType_t g_ExtType;

CExtension::CExtension(const char *filename, char *error, size_t err_max)

{

	m_File.assign(filename);

	m_pAPI = NULL;

	m_pIdentToken = NULL;

	m_PlId = 0;

	char path[PLATFORM_MAX_PATH+1];

	g_LibSys.PathFormat(path, PLATFORM_MAX_PATH, "%s/extensions/%s", g_SourceMod.GetSMBaseDir(), filename);

	m_pLib = g_LibSys.OpenLibrary(path, error, err_max);

	if (m_pLib == NULL)

	{

		return;

	}

	typedef IExtensionInterface *(*GETAPI)();

	GETAPI pfnGetAPI = NULL;

	if ((pfnGetAPI=(GETAPI)m_pLib->GetSymbolAddress("GetSMExtAPI")) == NULL)

	{

		m_pLib->CloseLibrary();

		m_pLib = NULL;

		snprintf(error, err_max, "Unable to find extension entry point");

		return;

	}

	m_pAPI = pfnGetAPI();

	if (!m_pAPI || m_pAPI->GetExtensionVersion() > SMINTERFACE_EXTENSIONAPI_VERSION)

	{

		m_pLib->CloseLibrary();

		m_pLib = NULL;

		snprintf(error, err_max, "Extension version is too new to load (%d, max is %d)", m_pAPI->GetExtensionVersion(), SMINTERFACE_EXTENSIONAPI_VERSION);

		return;

	}

	if (m_pAPI->IsMetamodExtension())

	{

		bool already;

		m_PlId = g_pMMPlugins->Load(path, g_PLID, already, error, err_max);

	}

	m_pIdentToken = g_ShareSys.CreateIdentity(g_ExtType);

	if (!m_pAPI->OnExtensionLoad(this, &g_ShareSys, error, err_max, g_SourceMod.IsLateLoadInMap()))

	{

		if (m_pAPI->IsMetamodExtension())

		{

			if (m_PlId)

			{

				char dummy[255];

				g_pMMPlugins->Unload(m_PlId, true, dummy, sizeof(dummy));

				m_PlId = 0;

			}

		}

		m_pAPI = NULL;

		m_pLib->CloseLibrary();

		m_pLib = NULL;

		g_ShareSys.DestroyIdentity(m_pIdentToken);

		m_pIdentToken = NULL;

		return;

	}

}

CExtension::~CExtension()

{

	if (m_pAPI)

	{

		m_pAPI->OnExtensionUnload();

		if (m_PlId)

		{

			g_pMMPlugins->Unload(m_PlId, true, NULL, 0);

		}

	}

	if (m_pIdentToken)

	{

		g_ShareSys.DestroyIdentity(m_pIdentToken);

	}

	if (m_pLib)

	{

		m_pLib->CloseLibrary();

	}

}

void CExtension::SetError(const char *error)

{

	m_Error.assign(error);

}

IExtensionInterface *CExtension::GetAPI()

{

	return m_pAPI;

}

const char *CExtension::GetFilename()

{

	return m_File.c_str();

}

IdentityToken_t *CExtension::GetIdentity()

{

	return m_pIdentToken;

}

bool CExtension::IsLoaded()

{

	return (m_pLib != NULL);

}

void CExtension::AddDependency(IfaceInfo *pInfo)

{

	m_Deps.push_back(*pInfo);

}

ITERATOR *CExtension::FindFirstDependency(IExtension **pOwner, SMInterface **pInterface)

{

	List<IfaceInfo>::iterator iter = m_Deps.begin();

	if (iter == m_Deps.end())

	{

		return NULL;

	}

	if (pOwner)

	{

		*pOwner = (*iter).owner;

	}

	if (pInterface)

	{

		*pInterface = (*iter).iface;

	}

	List<IfaceInfo>::iterator *pIter = new List<IfaceInfo>::iterator(iter);

	return (ITERATOR *)pIter;

}

bool CExtension::FindNextDependency(ITERATOR *iter, IExtension **pOwner, SMInterface **pInterface)

{

	List<IfaceInfo>::iterator *pIter = (List<IfaceInfo>::iterator *)iter;

	List<IfaceInfo>::iterator _iter;

	if (_iter == m_Deps.end())

	{

		return false;

	}

	_iter++;

	if (pOwner)

	{

		*pOwner = (*_iter).owner;

	}

	if (pInterface)

	{

		*pInterface = (*_iter).iface;

	}

	*pIter = _iter;

	if (_iter == m_Deps.end())

	{

		return false;

	}

	return true;

}

void CExtension::FreeDependencyIterator(ITERATOR *iter)

{

	List<IfaceInfo>::iterator *pIter = (List<IfaceInfo>::iterator *)iter;

	delete pIter;

}

void CExtension::AddInterface(SMInterface *pInterface)

{

	m_Interfaces.push_back(pInterface);

}

/*********************

 * EXTENSION MANAGER *

 *********************/

void CExtensionManager::OnSourceModAllInitialized()

{

	g_ExtType = g_ShareSys.CreateIdentType("EXTENSION");

}

void CExtensionManager::OnSourceModShutdown()

{

	g_ShareSys.DestroyIdentType(g_ExtType);

}

IExtension *CExtensionManager::LoadAutoExtension(const char *path)

{

	IExtension *pAlready;

	if ((pAlready=FindExtensionByFile(path)) != NULL)

	{

		return pAlready;

	}

	char error[256];

	CExtension *p = new CExtension(path, error, sizeof(error));

	if (!p->IsLoaded())

	{

		g_Logger.LogError("[SOURCEMOD] Unable to load extension \"%s\": %s", path, error);

		p->SetError(error);

	}

	m_Libs.push_back(p);

	return p;

}

IExtension *CExtensionManager::FindExtensionByFile(const char *file)

{

	List<CExtension *>::iterator iter;

	CExtension *pExt;

	/* Make sure the file direction is right */

	char path[PLATFORM_MAX_PATH+1];

	g_LibSys.PathFormat(path, PLATFORM_MAX_PATH, "%s", file);

	for (iter=m_Libs.begin(); iter!=m_Libs.end(); iter++)

	{

		pExt = (*iter);

		if (strcmp(pExt->GetFilename(), path) == 0)

		{

			return pExt;

		}

	}

	return NULL;

}

IExtension *CExtensionManager::FindExtensionByName(const char *ext)

{

	List<CExtension *>::iterator iter;

	CExtension *pExt;

	IExtensionInterface *pAPI;

	const char *name;

	for (iter=m_Libs.begin(); iter!=m_Libs.end(); iter++)

	{

		pExt = (*iter);

		if (!pExt->IsLoaded())

		{

			continue;

		}

		if ((pAPI = pExt->GetAPI()) == NULL)

		{

			continue;

		}

		name = pAPI->GetExtensionName();

		if (!name)

		{

			continue;

		}

		if (strcmp(name, ext) == 0)

		{

			return pExt;

		}

	}

	return NULL;

}

IExtension *CExtensionManager::LoadExtension(const char *file, ExtensionLifetime lifetime, char *error, size_t err_max)

{

	IExtension *pAlready;

	if ((pAlready=FindExtensionByFile(file)) != NULL)

	{

		return pAlready;

	}

	CExtension *pExt = new CExtension(file, error, err_max);

	/* :NOTE: lifetime is currently ignored */

	if (!pExt->IsLoaded())

	{

		delete pExt;

		return NULL;

	}

	m_Libs.push_back(pExt);

	return pExt;

}

void CExtensionManager::BindDependency(IExtension *pOwner, IfaceInfo *pInfo)

{

	CExtension *pExt = (CExtension *)pOwner;

	pExt->AddDependency(pInfo);

}

void CExtensionManager::AddInterface(IExtension *pOwner, SMInterface *pInterface)

{

	CExtension *pExt = (CExtension *)pOwner;

	pExt->AddInterface(pInterface);

}

bool CExtensionManager::UnloadExtension(IExtension *_pExt)

{

	if (!_pExt)

	{

		return false;

	}

	CExtension *pExt = (CExtension *)_pExt;

	if (m_Libs.find(pExt) == m_Libs.end())

	{

		return false;

	}

	/* First remove us from internal lists */

	g_ShareSys.RemoveInterfaces(_pExt);

	m_Libs.remove(pExt);

	List<CExtension *> UnloadQueue;

	/* Handle dependencies */

	if (pExt->IsLoaded())

	{

		/* Notify and/or unload all dependencies */

		List<CExtension *>::iterator c_iter;

		CExtension *pDep;

		IExtensionInterface *pAPI;

		for (c_iter = m_Libs.begin(); c_iter != m_Libs.end(); c_iter++)

		{

			pDep = (*c_iter);

			if ((pAPI=pDep->GetAPI()) == NULL)

			{

				continue;

			}

			/* Now, get its dependency list */

			bool dropped = false;

			List<IfaceInfo>::iterator i_iter = pDep->m_Deps.begin();

			while (i_iter != pDep->m_Deps.end())

			{

				if ((*i_iter).owner == _pExt)

				{

					if (!dropped && !pAPI->QueryInterfaceDrop((*i_iter).iface))

					{

						dropped = true;

					}

					pAPI->NotifyInterfaceDrop((*i_iter).iface);

					i_iter = pDep->m_Deps.erase(i_iter);

				} else {

					i_iter++;

				}

			}

		}

	}

	List<CExtension *>::iterator iter;

	for (iter=UnloadQueue.begin(); iter!=UnloadQueue.end(); iter++)

	{

		/* NOTE: This is safe because the unload function backs out of anything not present */

		UnloadExtension((*iter));

	}

	return true;

}