// Copyright (C) 2002-2009 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#include "IrrCompileConfig.h"

#include "CFileSystem.h"
#include "IReadFile.h"
#include "IWriteFile.h"
#include "CZipReader.h"
#include "CMountPointReader.h"
#include "CPakReader.h"
#include "CTarReader.h"
#include "CFileList.h"
#include "CXMLReader.h"
#include "CXMLWriter.h"
#include "stdio.h"
#include "os.h"
#include "CAttributes.h"
#include "CMemoryFile.h"
#include "CLimitReadFile.h"


#if defined (_IRR_WINDOWS_API_)
	#if !defined ( _WIN32_WCE )
		#include <direct.h> // for _chdir
	#endif
	#include <io.h> // for _access
#else
	#if (defined(_IRR_POSIX_API_) || defined(_IRR_OSX_PLATFORM_))
		#include <stdio.h>
		#include <stdlib.h>
		#include <string.h>
		#include <limits.h>
		#include <sys/types.h>
		#include <dirent.h>
		#include <sys/stat.h>
		#include <unistd.h>
	#endif
#endif

namespace irr
{
namespace io
{

//! constructor
CFileSystem::CFileSystem()
{
	#ifdef _DEBUG
	setDebugName("CFileSystem");
	#endif

	setFileListSystem(FILESYSTEM_NATIVE);
	//! reset current working directory
	getWorkingDirectory();

#ifdef __IRR_COMPILE_WITH_ZIP_ARCHIVE_LOADER_
	ArchiveLoader.push_back(new CArchiveLoaderZIP(this));
#endif

#ifdef __IRR_COMPILE_WITH_MOUNT_ARCHIVE_LOADER_
	ArchiveLoader.push_back(new CArchiveLoaderMount(this));
#endif

#ifdef __IRR_COMPILE_WITH_PAK_ARCHIVE_LOADER_
	ArchiveLoader.push_back(new CArchiveLoaderPAK(this));
#endif

#ifdef __IRR_COMPILE_WITH_TAR_ARCHIVE_LOADER_
	ArchiveLoader.push_back(new CArchiveLoaderTAR(this));
#endif
}


//! destructor
CFileSystem::~CFileSystem()
{
	u32 i;

	for ( i=0; i < FileArchives.size(); ++i)
	{
		FileArchives[i]->drop();
	}

	for ( i=0; i < ArchiveLoader.size(); ++i)
	{
		ArchiveLoader[i]->drop();
	}
}


//! opens a file for read access
IReadFile* CFileSystem::createAndOpenFile(const core::string<c16>& filename)
{
	IReadFile* file = 0;
	u32 i;

	for (i=0; i< FileArchives.size(); ++i)
	{
		file = FileArchives[i]->createAndOpenFile(filename);
		if (file)
			return file;
	}

	// Create the file using an absolute path so that it matches
	// the scheme used by CNullDriver::getTexture().
	return createReadFile(getAbsolutePath(filename));
}


//! Creates an IReadFile interface for treating memory like a file.
IReadFile* CFileSystem::createMemoryReadFile(void* memory, s32 len,
		const core::string<c16>& fileName, bool deleteMemoryWhenDropped)
{
	if (!memory)
		return 0;
	else
		return new CMemoryFile(memory, len, fileName, deleteMemoryWhenDropped);
}


//! Creates an IReadFile interface for reading files inside files
IReadFile* CFileSystem::createLimitReadFile(const core::string<c16>& fileName,
		IReadFile* alreadyOpenedFile, long pos, long areaSize)
{
	if (!alreadyOpenedFile)
		return 0;
	else
		return new CLimitReadFile(alreadyOpenedFile, pos, areaSize, fileName);
}


//! Creates an IReadFile interface for treating memory like a file.
IWriteFile* CFileSystem::createMemoryWriteFile(void* memory, s32 len,
		const core::string<c16>& fileName, bool deleteMemoryWhenDropped)
{
	if (!memory)
		return 0;
	else
		return new CMemoryFile(memory, len, fileName, deleteMemoryWhenDropped);
}


//! Opens a file for write access.
IWriteFile* CFileSystem::createAndWriteFile(const core::string<c16>& filename, bool append)
{
	return createWriteFile(filename, append);
}


//! Adds an external archive loader to the engine.
void CFileSystem::addArchiveLoader(IArchiveLoader* loader)
{
	if (!loader)
		return;

	loader->grab();
	ArchiveLoader.push_back(loader);
}


//! move the hirarchy of the filesystem. moves sourceIndex relative up or down
bool CFileSystem::moveFileArchive(u32 sourceIndex, s32 relative)
{
	bool r = false;
	const s32 dest = (s32) sourceIndex + relative;
	const s32 dir = relative < 0 ? -1 : 1;
	const s32 sourceEnd = ((s32) FileArchives.size() ) - 1;
	IFileArchive *t;

	for (s32 s = (s32) sourceIndex;s != dest; s += dir)
	{
		if (s < 0 || s > sourceEnd || s + dir < 0 || s + dir > sourceEnd)
			continue;

		t = FileArchives[s + dir];
		FileArchives[s + dir] = FileArchives[s];
		FileArchives[s] = t;
		r = true;
	}
	return r;
}


//! Adds an archive to the file system.
bool CFileSystem::addFileArchive(const core::string<c16>& filename, bool ignoreCase,
									  bool ignorePaths, E_FILE_ARCHIVE_TYPE archiveType)
{
	IFileArchive* archive = 0;
	bool ret = false;
	u32 i;

	// check if the archive was already loaded
	for (i = 0; i < FileArchives.size(); ++i)
	{
		if (filename == FileArchives[i]->getFileList()->getPath())
			return true;
	}

	// do we know what type it should be?
	if (archiveType == EFAT_UNKNOWN || archiveType == EFAT_FOLDER)
	{
		// try to load archive based on file name
		for (i = 0; i < ArchiveLoader.size(); ++i)
		{
			if (ArchiveLoader[i]->isALoadableFileFormat(filename))
			{
				archive = ArchiveLoader[i]->createArchive(filename, ignoreCase, ignorePaths);
				if (archive)
					break;
			}
		}

		// try to load archive based on content
		if (!archive)
		{
			io::IReadFile* file = createAndOpenFile(filename);
			if (file)
			{
				for (i = 0; i < ArchiveLoader.size(); ++i)
				{
					file->seek(0);
					if (ArchiveLoader[i]->isALoadableFileFormat(file))
					{
						file->seek(0);
						archive = ArchiveLoader[i]->createArchive(file, ignoreCase, ignorePaths);
						if (archive)
							break;
					}
				}
				file->drop();
			}
		}
	}
	else
	{
		// try to open archive based on archive loader type

		io::IReadFile* file = 0;

		for (i = 0; i < ArchiveLoader.size(); ++i)
		{
			if (ArchiveLoader[i]->isALoadableFileFormat(archiveType))
			{
				// attempt to open file
				if (!file)
					file = createAndOpenFile(filename);

				// is the file open?
				if (file)
				{
					// attempt to open archive
					file->seek(0);
					if (ArchiveLoader[i]->isALoadableFileFormat(file))
					{
						file->seek(0);
						archive = ArchiveLoader[i]->createArchive(file, ignoreCase, ignorePaths);
						if (archive)
							break;
					}
				}
				else
				{
					// couldn't open file
					break;
				}
			}
		}

		// if open, close the file
		if (file)
			file->drop();
	}

	if (archive)
	{
		FileArchives.push_back(archive);
		ret = true;
	}
	else
	{
		os::Printer::log("Could not create archive for", filename, ELL_ERROR);
	}

	_IRR_IMPLEMENT_MANAGED_MARSHALLING_BUGFIX;
	return ret;
}


//! removes an archive from the file system.
bool CFileSystem::removeFileArchive(u32 index)
{
	bool ret = false;
	if (index < FileArchives.size())
	{
		FileArchives[index]->drop();
		FileArchives.erase(index);
		ret = true;
	}
	_IRR_IMPLEMENT_MANAGED_MARSHALLING_BUGFIX;
	return ret;
}


//! removes an archive from the file system.
bool CFileSystem::removeFileArchive(const core::string<c16>& filename)
{
	for (u32 i=0; i < FileArchives.size(); ++i)
	{
		if (filename == FileArchives[i]->getFileList()->getPath())
			return removeFileArchive(i);
	}
	_IRR_IMPLEMENT_MANAGED_MARSHALLING_BUGFIX;
	return false;
}


//! gets an archive
u32 CFileSystem::getFileArchiveCount() const
{
	return FileArchives.size();
}


IFileArchive* CFileSystem::getFileArchive(u32 index)
{
	return index < getFileArchiveCount() ? FileArchives[index] : 0;
}


//! Returns the string of the current working directory
const core::string<c16>& CFileSystem::getWorkingDirectory()
{
	EFileSystemType type = FileSystemType;

	if (type != FILESYSTEM_NATIVE)
	{
		type = FILESYSTEM_VIRTUAL;
	}
	else
	{
		#if defined(_IRR_WINDOWS_CE_PLATFORM_)

		#elif defined(_IRR_WINDOWS_API_)
			#if defined(_IRR_WCHAR_FILESYSTEM )
				wchar_t tmp[_MAX_PATH];
				_wgetcwd(tmp, FILE_SYSTEM_MAX_PATH);
			#else
				c8 tmp[_MAX_PATH];
				_getcwd(tmp, _MAX_PATH);
			#endif
			WorkingDirectory[FILESYSTEM_NATIVE] = tmp;
		#endif

		#if (defined(_IRR_POSIX_API_) || defined(_IRR_OSX_PLATFORM_))

			//! getting the CWD is rather complex as we do not know the size
			//! so try it until the call was successful
			//! Note that neither the first nor the second parameter may be 0 according to POSIX

			#if defined(_IRR_WCHAR_FILESYSTEM )
				u32 pathSize=256;
				wchar_t *tmpPath = new wchar_t[pathSize];
				while ((pathSize < (1<<16)) && !(wgetcwd(tmpPath,pathSize)))
				{
					delete [] tmpPath;
					pathSize *= 2;
					tmpPath = new char[pathSize];
				}
				if (tmpPath)
				{
					WorkingDirectory[FILESYSTEM_NATIVE] = tmpPath;
					delete [] tmpPath;
				}
			#else
				u32 pathSize=256;
				char *tmpPath = new char[pathSize];
				while ((pathSize < (1<<16)) && !(getcwd(tmpPath,pathSize)))
				{
					delete [] tmpPath;
					pathSize *= 2;
					tmpPath = new char[pathSize];
				}
				if (tmpPath)
				{
					WorkingDirectory[FILESYSTEM_NATIVE] = tmpPath;
					delete [] tmpPath;
				}
			#endif
		#endif

		WorkingDirectory[type].validate();
	}

	return WorkingDirectory[type];
}


//! Changes the current Working Directory to the given string.
bool CFileSystem::changeWorkingDirectoryTo(const core::string<c16>& newDirectory)
{
	bool success=false;

	if (FileSystemType != FILESYSTEM_NATIVE)
	{
		WorkingDirectory[FILESYSTEM_VIRTUAL].append(newDirectory);
		flattenFilename(WorkingDirectory[FILESYSTEM_VIRTUAL], "");
		success = 1;
	}
	else
	{
		WorkingDirectory[FILESYSTEM_NATIVE] = newDirectory;

#if defined(_IRR_WINDOWS_CE_PLATFORM_)
		success = true;
#elif defined(_MSC_VER)
	#if defined(_IRR_WCHAR_FILESYSTEM)
		success=(_wchdir(newDirectory.c_str()) == 0);
	#else
		success=(_chdir(newDirectory.c_str()) == 0);
	#endif
#else
		success=(chdir(newDirectory.c_str()) == 0);
#endif
	}

	return success;
}


core::string<c16> CFileSystem::getAbsolutePath(const core::string<c16>& filename) const
{
	c16 *p=0;

#if defined(_IRR_WINDOWS_CE_PLATFORM_)
	return filename;
#elif defined(_IRR_WINDOWS_API_)

	#if defined(_IRR_WCHAR_FILESYSTEM )
		c16 fpath[_MAX_PATH];
		p = _wfullpath(fpath, filename.c_str(), _MAX_PATH);
	#else
		c8 fpath[_MAX_PATH];
		p = _fullpath(fpath, filename.c_str(), _MAX_PATH);
	#endif

#elif (defined(_IRR_POSIX_API_) || defined(_IRR_OSX_PLATFORM_))
	c8 fpath[4096];
	fpath[0]=0;
	p = realpath(filename.c_str(), fpath);
	if (!p)
	{
		// content in fpath is undefined at this point
		if (!fpath[0]) // seems like fpath wasn't altered
		{
			// at least remove a ./ prefix
			if ('.'==filename[0] && '/'==filename[1])
				return filename.subString(2, filename.size()-2);
			else
				return filename;
		}
		else
			return core::string<c16>(fpath);
	}

#endif

	return core::string<c16>(p);
}


//! returns the directory part of a filename, i.e. all until the first
//! slash or backslash, excluding it. If no directory path is prefixed, a '.'
//! is returned.
core::string<c16> CFileSystem::getFileDir(const core::string<c16>& filename) const
{
	// find last forward or backslash
	s32 lastSlash = filename.findLast('/');
	const s32 lastBackSlash = filename.findLast('\\');
	lastSlash = lastSlash > lastBackSlash ? lastSlash : lastBackSlash;

	if ((u32)lastSlash < filename.size())
		return filename.subString(0, lastSlash);
	else
		return ".";
}


//! returns the base part of a filename, i.e. all except for the directory
//! part. If no directory path is prefixed, the full name is returned.
core::string<c16> CFileSystem::getFileBasename(const core::string<c16>& filename, bool keepExtension) const
{
	// find last forward or backslash
	s32 lastSlash = filename.findLast('/');
	const s32 lastBackSlash = filename.findLast('\\');
	lastSlash = core::max_(lastSlash, lastBackSlash);

	// get number of chars after last dot
	s32 end = 0;
	if (!keepExtension)
	{
		// take care to search only after last slash to check only for
		// dots in the filename
		end = filename.findLast('.', lastSlash);
		if (end == -1)
			end=0;
		else
			end = filename.size()-end;
	}

	if ((u32)lastSlash < filename.size())
		return filename.subString(lastSlash+1, filename.size()-lastSlash-1-end);
	else if (end != 0)
		return filename.subString(0, filename.size()-end);
	else
		return filename;
}


//! flaten a path and file name for example: "/you/me/../." becomes "/you"
core::string<c16>& CFileSystem::flattenFilename(core::string<c16>& directory, const core::string<c16>& root) const
{
	directory.replace('\\', '/');
	if (lastChar(directory) != '/')
		directory.append('/');

	core::string<c16> dir;
	core::string<c16> subdir;

	s32 lastpos = 0;
	s32 pos = 0;

	while ((pos = directory.findNext('/', lastpos)) >= 0)
	{
		subdir = directory.subString(lastpos, pos - lastpos + 1);

		if (subdir == "../")
		{
			deletePathFromPath(dir, 2);
		}
		else if (subdir == "/")
		{
			dir = root;
		}
		else if (subdir != "./" )
		{
			dir.append(subdir);
		}

		lastpos = pos + 1;
	}
	directory = dir;
	return directory;
}


//! Creates a list of files and directories in the current working directory
EFileSystemType CFileSystem::setFileListSystem(EFileSystemType listType)
{
	EFileSystemType current = FileSystemType;
	FileSystemType = listType;
	return current;
}


//! Creates a list of files and directories in the current working directory
IFileList* CFileSystem::createFileList()
{
	CFileList* r = 0;
	core::string<c16> Path = getWorkingDirectory();
	Path.replace('\\', '/');
	if (lastChar(Path) != '/')
		Path.append('/');

	//! Construct from native filesystem
	if (FileSystemType == FILESYSTEM_NATIVE)
	{
		core::string<c16> fullPath;
		// --------------------------------------------
		//! Windows version
		#ifdef _IRR_WINDOWS_API_
		#if !defined ( _WIN32_WCE )

		r = new CFileList(Path, true, false);

		struct _finddata_t c_file;
		long hFile;

		if( (hFile = _findfirst( "*", &c_file )) != -1L )
		{
			do
			{
				fullPath = Path + c_file.name;

				r->addItem(fullPath, c_file.size, (_A_SUBDIR & c_file.attrib) != 0, 0);
			}
			while( _findnext( hFile, &c_file ) == 0 );

			_findclose( hFile );
		}
		#endif

		//TODO add drives
		//entry.Name = "E:\\";
		//entry.isDirectory = true;
		//Files.push_back(entry);
		#endif

		// --------------------------------------------
		//! Linux version
		#if (defined(_IRR_POSIX_API_) || defined(_IRR_OSX_PLATFORM_))


		r = new CFileList(Path, false, false);

		r->addItem(Path + "..", 0, true, 0);

		//! We use the POSIX compliant methods instead of scandir
		DIR* dirHandle=opendir(Path.c_str());
		if (dirHandle)
		{
			struct dirent *dirEntry;
			while ((dirEntry=readdir(dirHandle)))
			{
				u32 size = 0;
				bool isDirectory = false;
				fullPath = Path + dirEntry->d_name;

				if((strcmp(dirEntry->d_name, ".")==0) ||
				   (strcmp(dirEntry->d_name, "..")==0))
				{
					continue;
				}
				struct stat buf;
				if (stat(dirEntry->d_name, &buf)==0)
				{
					size = buf.st_size;
					isDirectory = S_ISDIR(buf.st_mode);
				}
				#if !defined(_IRR_SOLARIS_PLATFORM_) && !defined(__CYGWIN__)
				// only available on some systems
				else
				{
					isDirectory = dirEntry->d_type == DT_DIR;
				}
				#endif

				r->addItem(fullPath, size, isDirectory, 0);
			}
			closedir(dirHandle);
		}
		#endif
	}
	else
	{
		//! create file list for the virtual filesystem
		r = new CFileList(Path, false, false);

		//! add relative navigation
		SFileListEntry e2;
		SFileListEntry e3;

		//! PWD
		r->addItem(Path + ".", 0, true, 0);

		//! parent
		r->addItem(Path + "..", 0, true, 0);

		//! merge archives
		for (u32 i=0; i < FileArchives.size(); ++i)
		{
			const IFileList *merge = FileArchives[i]->getFileList();

			for (u32 j=0; j < merge->getFileCount(); ++j)
			{
				if (core::isInSameDirectory(Path, merge->getFullFileName(j)) == 0)
				{
					core::string<c16> fullPath = merge->getFullFileName(j);
					r->addItem(fullPath, merge->getFileSize(j), merge->isDirectory(j), 0);
				}
			}
		}

	}

	if (r)
		r->sort();
	return r;
}

//! determines if a file exists and would be able to be opened.
bool CFileSystem::existFile(const core::string<c16>& filename) const
{
	for (u32 i=0; i < FileArchives.size(); ++i)
		if (FileArchives[i]->getFileList()->findFile(filename)!=-1)
			return true;

	_IRR_IMPLEMENT_MANAGED_MARSHALLING_BUGFIX;
#if defined(_IRR_WCHAR_FILESYSTEM)
	return (_waccess(filename.c_str(), 0) != -1);
#elif defined(_MSC_VER)
	return (_access(filename.c_str(), 0) != -1);
#else
	return (access(filename.c_str(), F_OK) != -1);
#endif
}


//! Creates a XML Reader from a file.
IXMLReader* CFileSystem::createXMLReader(const core::string<c16>& filename)
{
	IReadFile* file = createAndOpenFile(filename);
	if (!file)
		return 0;

	IXMLReader* reader = createXMLReader(file);
	file->drop();
	return reader;
}


//! Creates a XML Reader from a file.
IXMLReader* CFileSystem::createXMLReader(IReadFile* file)
{
	if (!file)
		return 0;

	return createIXMLReader(file);
}


//! Creates a XML Reader from a file.
IXMLReaderUTF8* CFileSystem::createXMLReaderUTF8(const core::string<c16>& filename)
{
	IReadFile* file = createAndOpenFile(filename);
	if (!file)
		return 0;

	IXMLReaderUTF8* reader = createIXMLReaderUTF8(file);
	file->drop();
	return reader;
}


//! Creates a XML Reader from a file.
IXMLReaderUTF8* CFileSystem::createXMLReaderUTF8(IReadFile* file)
{
	if (!file)
		return 0;

	return createIXMLReaderUTF8(file);
}


//! Creates a XML Writer from a file.
IXMLWriter* CFileSystem::createXMLWriter(const core::string<c16>& filename)
{
	IWriteFile* file = createAndWriteFile(filename);
	IXMLWriter* writer = createXMLWriter(file);
	file->drop();
	return writer;
}


//! Creates a XML Writer from a file.
IXMLWriter* CFileSystem::createXMLWriter(IWriteFile* file)
{
	return new CXMLWriter(file);
}


//! creates a filesystem which is able to open files from the ordinary file system,
//! and out of zipfiles, which are able to be added to the filesystem.
IFileSystem* createFileSystem()
{
	return new CFileSystem();
}


//! Creates a new empty collection of attributes, usable for serialization and more.
IAttributes* CFileSystem::createEmptyAttributes(video::IVideoDriver* driver)
{
	return new CAttributes(driver);
}


} // end namespace irr
} // end namespace io

