/*
 * This file is subject to the terms of the GFX License. If a copy of
 * the license was not distributed with this file, you can obtain one at:
 *
 *              http://ugfx.org/license.html
 */

/********************************************************
 * The native file-system
 ********************************************************/

// We need to include stdio.h below. Turn off GFILE_NEED_STDIO just for this file to prevent conflicts
#define GFILE_NEED_STDIO_MUST_BE_OFF

#include "gfx.h"

#if GFX_USE_GFILE && GFILE_NEED_NATIVEFS

#include "gfile_fs.h"

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>

static bool_t NativeDel(const char *fname);
static bool_t NativeExists(const char *fname);
static long int	NativeFilesize(const char *fname);
static bool_t NativeRen(const char *oldname, const char *newname);
static bool_t NativeOpen(GFILE *f, const char *fname);
static void NativeClose(GFILE *f);
static int NativeRead(GFILE *f, void *buf, int size);
static int NativeWrite(GFILE *f, const void *buf, int size);
static bool_t NativeSetpos(GFILE *f, long int pos);
static long int NativeGetsize(GFILE *f);
static bool_t NativeEof(GFILE *f);
#if GFILE_NEED_FILELISTS
	static gfileList *NativeFlOpen(const char *path, bool_t dirs);
	static const char *NativeFlRead(gfileList *pfl);
	static void NativeFlClose(gfileList *pfl);
#endif

const GFILEVMT FsNativeVMT = {
	#if defined(WIN32) || GFX_USE_OS_WIN32
		GFSFLG_TEXTMODES|
	#else
		GFSFLG_CASESENSITIVE|
	#endif
	GFSFLG_WRITEABLE|GFSFLG_SEEKABLE|GFSFLG_FAST,		// flags
	'N',												// prefix
	NativeDel, NativeExists, NativeFilesize, NativeRen,
	NativeOpen, NativeClose, NativeRead, NativeWrite,
	NativeSetpos, NativeGetsize, NativeEof,
	0, 0, 0,
	#if GFILE_NEED_FILELISTS
		NativeFlOpen, NativeFlRead, NativeFlClose
	#endif
};

void _gfileNativeAssignStdio(void) {
	static GFILE NativeStdIn;
	static GFILE NativeStdOut;
	static GFILE NativeStdErr;

	NativeStdIn.flags = GFILEFLG_OPEN|GFILEFLG_READ;
	NativeStdIn.vmt = &FsNativeVMT;
	NativeStdIn.obj = (void *)stdin;
	NativeStdIn.pos = 0;
	gfileStdIn = &NativeStdIn;
	NativeStdOut.flags = GFILEFLG_OPEN|GFILEFLG_WRITE|GFILEFLG_APPEND;
	NativeStdOut.vmt = &FsNativeVMT;
	NativeStdOut.obj = (void *)stdout;
	NativeStdOut.pos = 0;
	gfileStdOut = &NativeStdOut;
	NativeStdErr.flags = GFILEFLG_OPEN|GFILEFLG_WRITE|GFILEFLG_APPEND;
	NativeStdErr.vmt = &FsNativeVMT;
	NativeStdErr.obj = (void *)stderr;
	NativeStdErr.pos = 0;
	gfileStdErr = &NativeStdErr;
}

static void Native_flags2mode(char *buf, uint16_t flags) {
	if (flags & GFILEFLG_MUSTEXIST)
		*buf = 'r';
	else if (flags & GFILEFLG_APPEND)
		*buf = 'a';
	else
		*buf = 'w';
	buf++;
	if ((flags & (GFILEFLG_READ|GFILEFLG_WRITE)) == (GFILEFLG_READ|GFILEFLG_WRITE))
		*buf++ = '+';
	if (flags & GFILEFLG_BINARY)
		*buf++ = 'b';
	if (flags & GFILEFLG_MUSTNOTEXIST)
		*buf++ = 'x';
	*buf++ = 0;
}

static bool_t NativeDel(const char *fname)							{ return remove(fname) ? FALSE : TRUE; }
static void NativeClose(GFILE *f)									{ fclose((FILE *)f->obj); }
static int NativeRead(GFILE *f, void *buf, int size)				{ return fread(buf, 1, size, (FILE *)f->obj); }
static int NativeWrite(GFILE *f, const void *buf, int size)			{ return fwrite(buf, 1, size, (FILE *)f->obj); }
static bool_t NativeSetpos(GFILE *f, long int pos)					{ return fseek((FILE *)f->obj, pos, SEEK_SET) ?  FALSE : TRUE; }
static bool_t NativeEof(GFILE *f)									{ return feof((FILE *)f->obj) ? TRUE : FALSE; }
static bool_t NativeRen(const char *oldname, const char *newname)	{ return rename(oldname, newname) ? FALSE : TRUE; }
static bool_t NativeExists(const char *fname) {
	// We define access this way so we don't have to include <unistd.h> which may
	//	(and does under windows) contain conflicting definitions for types such as uint16_t.
	extern int access(const char *pathname, int mode);
	return access(fname, 0) ? FALSE : TRUE;
}
static long int	NativeFilesize(const char *fname) {
	struct stat st;
	if (stat(fname, &st)) return -1;
	return st.st_size;
}
static bool_t NativeOpen(GFILE *f, const char *fname) {
	FILE *fd;
	char mode[5];

	Native_flags2mode(mode, f->flags);
	if (!(fd = fopen(fname, mode)))
		return FALSE;
	f->obj = (void *)fd;
	return TRUE;
}
static long int NativeGetsize(GFILE *f) {
	struct stat st;
	if (fstat(fileno((FILE *)f->obj), &st)) return -1;
	return st.st_size;
}

#if GFILE_NEED_FILELISTS
	#if defined(WIN32) || GFX_USE_OS_WIN32
		typedef struct NativeFileList {
			gfileList			fl;
			HANDLE				d;
			WIN32_FIND_DATA		f;
			bool_t				first;
		} NativeFileList;

		static gfileList *NativeFlOpen(const char *path, bool_t dirs) {
			NativeFileList		*p;
			(void)				dirs;

			if (!(p = gfxAlloc(sizeof(NativeFileList))))
				return 0;
			if ((p->d = FindFirstFile(path, &p->f)) == INVALID_HANDLE_VALUE) {
				gfxFree(p);
				return 0;
			}
			p->first = TRUE;
			return &p->fl;
		}

		static const char *NativeFlRead(gfileList *pfl) {
			#define nfl		((NativeFileList *)pfl)
			while(1) {
				if (!nfl->first && !FindNextFile(nfl->d, &nfl->f))
					return 0;
				nfl->first = FALSE;
				if (nfl->f.cFileName[0] == '.')
					continue;
				if (nfl->fl.dirs) {
					if ((nfl->f.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
						break;
				} else {
					if (!(nfl->f.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
						break;
				}
			}
			return nfl->f.cFileName;
			#undef nfl
		}

		static void NativeFlClose(gfileList *pfl) {
			CloseHandle(((NativeFileList *)pfl)->d);
			gfxFree(pfl);
		}

	#else
		#include <dirent.h>

		typedef struct NativeFileList {
			gfileList			fl;
			DIR *				d;
			struct dirent *		f;
		} NativeFileList;

		static gfileList *NativeFlOpen(const char *path, bool_t dirs) {
			NativeFileList		*p;
			(void)				dirs;

			if (!(p = gfxAlloc(sizeof(NativeFileList))))
				return 0;
			if (!(p->d = opendir(path))) {
				gfxFree(p);
				return 0;
			}
			return &p->fl;
		}

		static const char *NativeFlRead(gfileList *pfl) {
			#define nfl		((NativeFileList *)pfl)
			while(1) {
				if (!(nfl->f = readdir(nfl->d)))
					return 0;
				if (nfl->f->d_name[0] == '.')
					continue;

				#ifdef _DIRENT_HAVE_D_TYPE
					if (nfl->fl.dirs) {
						if (nfl->f->d_type == DT_DIR)
							break;
					} else {
						if (nfl->f->d_type == DT_REG)
							break;
					}
				#else
					// Oops - no type field. We could use stat() here but that would mean
					//			concatting the supplied path to the found filename.
					//			That all just seems too hard. Instead we just don't
					//			distinguish between files and directories.
					break;
				#endif
			}
			return nfl->f->d_name;
			#undef nfl
		}

		static void NativeFlClose(gfileList *pfl) {
			closedir(((NativeFileList *)pfl)->d);
			gfxFree(pfl);
		}
	#endif
#endif

#endif //GFX_USE_GFILE && GFILE_NEED_NATIVEFS