// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 1993-2008 Raven Software
// Copyright(C) 2005 Simon Howard
//
// 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., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
// DESCRIPTION:
//      Miscellaneous.
//
//-----------------------------------------------------------------------------


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>

#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <io.h>
#ifdef _MSC_VER
#include <direct.h>
#endif
#else
#include <sys/stat.h>
#include <sys/types.h>
#endif

#include "doomtype.h"

#include "deh_str.h"

#include "i_swap.h"
#include "i_system.h"
#include "i_video.h"
#include "m_misc.h"
#include "v_video.h"
#include "w_wad.h"
#include "z_zone.h"

//
// Create a directory
//

void M_MakeDirectory(char *path)
{
#ifdef _WIN32
    mkdir(path);
#else
    mkdir(path, 0755);
#endif
}

// Check if a file exists

boolean M_FileExists(char *filename)
{
    FILE *fstream;

    fstream = fopen(filename, "r");

    if (fstream != NULL)
    {
        fclose(fstream);
        return true;
    }
    else
    {
        // If we can't open because the file is a directory, the 
        // "file" exists at least!

        return errno == EISDIR;
    }
}

//
// Determine the length of an open file.
//

long M_FileLength(FILE *handle)
{ 
    long savedpos;
    long length;

    // save the current position in the file
    savedpos = ftell(handle);
    
    // jump to the end and find the length
    fseek(handle, 0, SEEK_END);
    length = ftell(handle);

    // go back to the old location
    fseek(handle, savedpos, SEEK_SET);

    return length;
}

//
// M_WriteFile
//

boolean M_WriteFile(char *name, void *source, int length)
{
    FILE *handle;
    int	count;
	
    handle = fopen(name, "wb");

    if (handle == NULL)
	return false;

    count = fwrite(source, 1, length, handle);
    fclose(handle);
	
    if (count < length)
	return false;
		
    return true;
}


//
// M_ReadFile
//

int M_ReadFile(char *name, byte **buffer)
{
    FILE *handle;
    int	count, length;
    byte *buf;
	
    handle = fopen(name, "rb");
    if (handle == NULL)
	I_Error ("Couldn't read file %s", name);

    // find the size of the file by seeking to the end and
    // reading the current position

    length = M_FileLength(handle);
    
    buf = Z_Malloc (length, PU_STATIC, NULL);
    count = fread(buf, 1, length, handle);
    fclose (handle);
	
    if (count < length)
	I_Error ("Couldn't read file %s", name);
		
    *buffer = buf;
    return length;
}

// Returns the path to a temporary file of the given name, stored
// inside the system temporary directory.
//
// The returned value must be freed with Z_Free after use.

char *M_TempFile(char *s)
{
    char *result;
    char *tempdir;

#ifdef _WIN32

    // Check the TEMP environment variable to find the location.

    tempdir = getenv("TEMP");

    if (tempdir == NULL)
    {
        tempdir = ".";
    }
#else
    // In Unix, just use /tmp.

    tempdir = "/tmp";
#endif

    result = Z_Malloc(strlen(tempdir) + strlen(s) + 2, PU_STATIC, 0);
    sprintf(result, "%s%c%s", tempdir, DIR_SEPARATOR, s);

    return result;
}

boolean M_StrToInt(const char *str, int *result)
{
    return sscanf(str, " 0x%x", result) == 1
        || sscanf(str, " 0X%x", result) == 1
        || sscanf(str, " 0%o", result) == 1
        || sscanf(str, " %d", result) == 1;
}

void M_ExtractFileBase(char *path, char *dest)
{
    char *src;
    char *filename;
    int length;

    src = path + strlen(path) - 1;

    // back up until a \ or the start
    while (src != path && *(src - 1) != DIR_SEPARATOR)
    {
	src--;
    }

    filename = src;

    // Copy up to eight characters
    // Note: Vanilla Doom exits with an error if a filename is specified
    // with a base of more than eight characters.  To remove the 8.3
    // filename limit, instead we simply truncate the name.

    length = 0;
    memset(dest, 0, 8);

    while (*src != '\0' && *src != '.')
    {
        if (length >= 8)
        {
            printf("Warning: Truncated '%s' lump name to '%.8s'.\n",
                   filename, dest);
            break;
        }

	dest[length++] = toupper((int)*src++);
    }
}

//---------------------------------------------------------------------------
//
// PROC M_ForceUppercase
//
// Change string to uppercase.
//
//---------------------------------------------------------------------------

void M_ForceUppercase(char *text)
{
    char *p;

    for (p = text; *p != '\0'; ++p)
    {
        *p = toupper(*p);
    }
}

//
// M_StrCaseStr
//
// Case-insensitive version of strstr()
//

char *M_StrCaseStr(char *haystack, char *needle)
{
    unsigned int haystack_len;
    unsigned int needle_len;
    unsigned int len;
    unsigned int i;

    haystack_len = strlen(haystack);
    needle_len = strlen(needle);

    if (haystack_len < needle_len)
    {
        return NULL;
    }

    len = haystack_len - needle_len;

    for (i = 0; i <= len; ++i)
    {
        if (!strncasecmp(haystack + i, needle, needle_len))
        {
            return haystack + i;
        }
    }

    return NULL;
}

//
// String replace function.
// Returns a Z_Malloc()ed string.
//

char *M_StringReplace(char *haystack, char *needle, char *replacement)
{
    char *result, *p, *dst;
    size_t needle_len = strlen(needle);
    int n;

    // Count number of occurrences of 'p':

    for (p = haystack, n = 0;; ++n)
    {
        p = strstr(p, needle);

        if (p == NULL)
        {
            break;
        }

        p += needle_len;
    }

    // Construct new string.

    result = Z_Malloc(strlen(haystack)
                      + (strlen(replacement) - needle_len) * n
                      + 1,
                      PU_STATIC, NULL);

    dst = result;
    p = haystack;

    while (*p != '\0')
    {
        if (!strncmp(p, needle, needle_len))
        {
            strcpy(dst, replacement);
            dst += strlen(replacement);
            p += needle_len;
        }
        else
        {
            *dst = *p;
            ++dst;
            ++p;
        }
    }
    *dst = '\0';

    return result;
}

#ifdef _WIN32

char *M_OEMToUTF8(const char *oem)
{
    unsigned int len = strlen(oem) + 1;
    wchar_t *tmp;
    char *result;

    tmp = malloc(len * sizeof(wchar_t));
    MultiByteToWideChar(CP_OEMCP, 0, oem, len, tmp, len);
    result = malloc(len * 4);
    WideCharToMultiByte(CP_UTF8, 0, tmp, len, result, len * 4, NULL, NULL);
    free(tmp);

    return result;
}

#endif