/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

/* Original code:
 * Implementation for standard and semi-standard C library calls missing in WinCE
 * environment.
 * by Vasyl Tsvirkunov
 */


#include <windows.h>
#include <tchar.h>
#include <string.h>
#include <stdlib.h>
#include "sys/stat.h"
#ifndef __GNUC__
#include "sys/time.h"
#else
#include <stdio.h>
#endif
#include "time.h"
#include "dirent.h"
#include "common/debug.h"

char *strdup(const char *strSource);

#ifdef __GNUC__
#define EXT_C extern "C"
#else
#define EXT_C
#endif

// common missing functions required by both gcc and evc

void *bsearch(const void *key, const void *base, size_t nmemb,
			  size_t size, int (*compar)(const void *, const void *)) {
	// Perform binary search
	size_t lo = 0;
	size_t hi = nmemb;
	while (lo < hi) {
		size_t mid = (lo + hi) / 2;
		const void *p = ((const char *)base) + mid * size;
		int tmp = (*compar)(key, p);
		if (tmp < 0)
			hi = mid;
		else if (tmp > 0)
			lo = mid + 1;
		else
			return (void *)p;
	}

	return NULL;
}

static WIN32_FIND_DATA wfd;

int stat(const char *fname, struct stat *ss) {
	TCHAR fnameUnc[MAX_PATH+1];
	HANDLE handle;
	int len;

	if (fname == NULL || ss == NULL)
		return -1;

	/* Special case (dummy on WinCE) */
	len = strlen(fname);
	if (len >= 2 && fname[len-1] == '.' && fname[len-2] == '.' &&
		(len == 2 || fname[len-3] == '\\')) {
		/* That's everything implemented so far */
		memset(ss, 0, sizeof(struct stat));
		ss->st_size = 1024;
		ss->st_mode |= S_IFDIR;
		return 0;
	}

	MultiByteToWideChar(CP_ACP, 0, fname, -1, fnameUnc, MAX_PATH);
	handle = FindFirstFile(fnameUnc, &wfd);
	FindClose(handle);
	if (handle == INVALID_HANDLE_VALUE)
		return -1;
	else
	{
		/* That's everything implemented so far */
		memset(ss, 0, sizeof(struct stat));
		ss->st_size = wfd.nFileSizeLow;
		if (wfd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
			ss->st_mode |= S_IFDIR;
	}
	return 0;
}

char cwd[MAX_PATH+1] = "";
EXT_C char *getcwd(char *buffer, int maxlen) {
	TCHAR fileUnc[MAX_PATH+1];
	char* plast;

	if (cwd[0] == 0) {
		GetModuleFileName(NULL, fileUnc, MAX_PATH);
		WideCharToMultiByte(CP_ACP, 0, fileUnc, -1, cwd, MAX_PATH, NULL, NULL);
		plast = strrchr(cwd, '\\');
		if (plast)
			*plast = 0;
		/* Special trick to keep start menu clean... */
		if (_stricmp(cwd, "\\windows\\start menu") == 0)
			strcpy(cwd, "\\Apps");
	}
	if (buffer)
		strncpy(buffer, cwd, maxlen);
	return cwd;
}

#ifdef __GNUC__
#undef GetCurrentDirectory
#endif
EXT_C void GetCurrentDirectory(int len, char *buf) {
	getcwd(buf,len);
}

/*
Windows CE fopen has non-standard behavior -- not
fully qualified paths refer to root folder rather
than current folder (concept not implemented in CE).
*/
#undef fopen
EXT_C FILE *wce_fopen(const char* fname, const char* fmode) {
	char fullname[MAX_PATH+1];

	if (!fname || fname[0] == '\0')
		return NULL;
	if (fname[0] != '\\' && fname[0] != '/') {
		getcwd(fullname, MAX_PATH);
		strcat(fullname, "\\");
		strcat(fullname, fname);
		return fopen(fullname, fmode);
	} else
		return fopen(fname, fmode);
}

/* Remove file by name */
int remove(const char* path) {
	TCHAR pathUnc[MAX_PATH+1];
	MultiByteToWideChar(CP_ACP, 0, path, -1, pathUnc, MAX_PATH);
	return !DeleteFile(pathUnc);
}


/* check out file access permissions */
int _access(const char *path, int mode) {
	TCHAR fname[MAX_PATH];
	char fullname[MAX_PATH+1];

	if (path[0] != '\\' && path[0] != '/') {
		getcwd(fullname, MAX_PATH);
		strcat(fullname, "\\");
		strcat(fullname, path);
		MultiByteToWideChar(CP_ACP, 0, fullname, -1, fname, sizeof(fname)/sizeof(TCHAR));
	} else
		MultiByteToWideChar(CP_ACP, 0, path, -1, fname, sizeof(fname)/sizeof(TCHAR));

	WIN32_FIND_DATA ffd;
	HANDLE h = FindFirstFile(fname, &ffd);
	FindClose(h);

	if (h == INVALID_HANDLE_VALUE) {
		// WORKAROUND: WinCE 3.0 doesn't find paths ending in '\'
		if (path[strlen(path)-1] == '\\') {
			char p2[MAX_PATH];
			strncpy(p2, path, strlen(path)-1);
			p2[strlen(path) - 1]= '\0';
			return _access(p2, mode);
		} else
			return -1;  //Can't find file
	}

	if (ffd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
		// WORKAROUND: WinCE (or the emulator) sometimes returns bogus directory
		// hits for files that don't exist. TRIPLE checking for the same fname
		// seems to weed out those false positives.
		// Exhibited in kyra engine.
		HANDLE h = FindFirstFile(fname, &ffd);
		FindClose(h);
		if (h == INVALID_HANDLE_VALUE)
			return -1;  //Can't find file
		h = FindFirstFile(fname, &ffd);
		FindClose(h);
		if (h == INVALID_HANDLE_VALUE)
			return -1;  //Can't find file

		return 0; //Always return success if target is directory and exists
	}
	switch (mode) {
		case 00: //Check existence
			return 0;
		case 06: //Check Read & Write permission
		case 02: //Check Write permission
			return ffd.dwFileAttributes & FILE_ATTRIBUTE_READONLY ? -1 : 0;
		case 04: //Check Read permission
			return 0; //Assume always have read permission
	}
	//Bad mode value supplied, return failure
	return -1;
}

// evc only functions follow
#ifndef __GNUC__

/* Limited dirent implementation. Used by UI.C and DEVICES.C */
DIR* opendir(const char* fname) {
	DIR* pdir;
	char fnameMask[MAX_PATH+1];
	TCHAR fnameUnc[MAX_PATH+1];
	char nameFound[MAX_PATH+1];

	if (fname == NULL)
		return NULL;

	strcpy(fnameMask, fname);
	if (!strlen(fnameMask) || fnameMask[strlen(fnameMask)-1] != '\\')
		strncat(fnameMask, "\\", MAX_PATH-strlen(fnameMask)-1);
	strncat(fnameMask, "*.*", MAX_PATH-strlen(fnameMask)-4);

	pdir = (DIR*)malloc(sizeof(DIR)+strlen(fname));
	pdir->dd_dir.d_ino = 0;
	pdir->dd_dir.d_reclen = 0;
	pdir->dd_dir.d_name = 0;
	pdir->dd_dir.d_namlen = 0;

	pdir->dd_handle = 0;
	pdir->dd_stat = 0;
	strcpy(pdir->dd_name, fname); /* it has exactly enough space for fname and nul char */

	MultiByteToWideChar(CP_ACP, 0, fnameMask, -1, fnameUnc, MAX_PATH);
	if ((pdir->dd_handle = (long)FindFirstFile(fnameUnc, &wfd)) == (long)INVALID_HANDLE_VALUE) {
		free(pdir);
		return NULL;
	} else {
		WideCharToMultiByte(CP_ACP, 0, wfd.cFileName, -1, nameFound, MAX_PATH, NULL, NULL);

		pdir->dd_dir.d_name = strdup(nameFound);
		pdir->dd_dir.d_namlen = strlen(nameFound);
	}
	return pdir;
}

struct dirent* readdir(DIR* dir) {
	char nameFound[MAX_PATH+1];
	static struct dirent dummy;

	if (dir->dd_stat == 0) {
		dummy.d_name = ".";
		dummy.d_namlen = 1;
		dir->dd_stat ++;
		return &dummy;
	} else if (dir->dd_stat == 1) {
		dummy.d_name = "..";
		dummy.d_namlen = 2;
		dir->dd_stat ++;
		return &dummy;
	} else if (dir->dd_stat == 2) {
		dir->dd_stat++;
		return &dir->dd_dir;
	} else {
		if (FindNextFile((HANDLE)dir->dd_handle, &wfd) == 0) {
			dir->dd_stat = -1;
			return NULL;
		}
		WideCharToMultiByte(CP_ACP, 0, wfd.cFileName, -1, nameFound, MAX_PATH, NULL, NULL);

		free(dir->dd_dir.d_name);

		dir->dd_dir.d_name = strdup(nameFound);
		dir->dd_dir.d_namlen = strlen(nameFound);

		dir->dd_stat ++;

		return &dir->dd_dir;
	}
}

int closedir(DIR* dir) {
	if (dir == NULL)
		return 0;

	if (dir->dd_handle)
		FindClose((HANDLE)dir->dd_handle);

	free(dir->dd_dir.d_name);
	free(dir);
	return 1;
}

/* Make directory, Unix style */
void mkdir(char* dirname, int mode) {
	char  path[MAX_PATH+1];
	TCHAR pathUnc[MAX_PATH+1];
	char *ptr;
	strncpy(path, dirname, MAX_PATH);
	if (*path == '/')
		*path = '\\';
	/* Run through the string and attempt creating all subdirs on the path */
	for (ptr = path+1; *ptr; ptr ++) {
		if (*ptr == '\\' || *ptr == '/') {
			*ptr = 0;
			MultiByteToWideChar(CP_ACP, 0, path, -1, pathUnc, MAX_PATH);
			CreateDirectory(pathUnc, 0);
			*ptr = '\\';
		}
	}
	MultiByteToWideChar(CP_ACP, 0, path, -1, pathUnc, MAX_PATH);
	CreateDirectory(pathUnc, 0);
}

char *strdup(const char *strSource) {
	char *buffer;
	size_z len = strlen(strSource) + 1;
	buffer = (char*)malloc(len);
	if (buffer)
		memcpy(buffer, strSource, len);
	return buffer;
}

// gcc build only functions follow
#else // defined(__GNUC__)

#ifndef __MINGW32CE__
int islower(int c) {
	return (c>='a' && c<='z');
}

int isspace(int c) {
	return (c==' ' || c=='\f' || c=='\n' || c=='\r' || c=='\t' || c=='\v');
}

int isalpha(int c) {
	return ((c>='a' && c<='z') || (c>='A' && c<='Z'));
}

int isalnum(int c) {
	return ((c>='a' && c<='z') || (c>='A' && c<='Z') || (c>='0' && c<='9'));
}

int isprint(int c) {
	//static const char punct[] = "!\"#%&'();<=>?[\\]*+,-./:^_{|}~";
	//return (isalnum(c) || strchr(punct, c));
	return (32 <= c && c <= 126);	// based on BSD manpage
}
#endif

#endif