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

#if !defined(VMS) && !defined(_WIN32)
#include <unistd.h>
#else
#include <io.h>
#define lseek _lseek
#endif

#include "gks.h"
#include "gkscore.h"

#if defined(_WIN32)
#define STRSAFE_NO_DEPRECATE
#define _CRT_NON_CONFORMING_WCSTOK
#define __STRSAFE__NO_INLINE
#include <windows.h>
#include <strsafe.h>
#endif

#ifndef MAXPATHLEN
#define MAXPATHLEN 1024
#endif

static int font_cache[95], bufcache[95][256], gks = -1;

int gks_open_font(void)
{
  const char *path;
  char fontdb[MAXPATHLEN];
  int fd;

#ifndef _WIN32
  path = gks_getenv("GKS_FONTPATH");
  if (path == NULL)
    {
      path = gks_getenv("GRDIR");
      if (path == NULL) path = GRDIR;
    }
  strcpy(fontdb, (char *)path);
  strcat(fontdb, "/fonts/gksfont.dat");
#else
  wchar_t wfontdb[MAXPATHLEN];
  if (!GetEnvironmentVariableW(L"GKS_FONTPATH", wfontdb, MAXPATHLEN))
    {
      if (!GetEnvironmentVariableW(L"GRDIR", wfontdb, MAXPATHLEN))
        {
          MultiByteToWideChar(CP_UTF8, MB_PRECOMPOSED, GRDIR, -1, wfontdb, MAXPATHLEN);
        }
    }
  StringCbCatW(wfontdb, MAXPATHLEN, L"\\FONTS\\GKSFONT.DAT");
  WideCharToMultiByte(CP_UTF8, 0, wfontdb, wcslen(wfontdb) + 1, fontdb, MAXPATHLEN, NULL, NULL);
#endif
  fd = gks_open_file(fontdb, "r");

  return fd;
}

void gks_lookup_font(int fd, int version, int font, int chr, stroke_data_t *s)
{
  /*  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 */
  static int map[] = {1, 18, 1, 6, 12, 3, 8, 11, 4, 7, 10, 2, 13, 14, 5, 9, 15, 16, 17, 20, 21, 19, 22, 23};
  static int gksgralmap[] = {1, 12, 6, 9, 8, 11, 5, 13, 18, 17, 19, 1, 4, 7, 24, 1, 1, 1, 1, 1, 1, 1, 23, 24};
  static int s_map[] = {4, 4, 4, 4, 4, 7, 7, 7, 10, 10, 10, 7, 7, 7, 4, 4, 7, 7, 7, 4, 4, 4, 4, 4};

  static int german[] = {196, 214, 220, 228, 246, 252, 223, 171, 187, 183, 169};
  static char ansi[] = {'A', 'O', 'U', 'a', 'o', 'u', 'b', '<', '>', '.', '@'};
  static char greek[] = {'j', 'o', 'q', 'u', 'v', 'w', 'y', 'J', 'O', 'Q', 'U', 'V', 'W', 'Y'};
  static char g_map[] = {' ', 'w', ' ', 'o', 'y', 'v', 'q', ' ', 'W', ' ', 'O', 'Y', 'V', 'Q'};

  char buf[256];
  int umlaut, sharp_s, offset;
  int i, *elptr;
  char *ebptr;

  if (gks == -1)
    {
      for (i = 0; i < 95; i++) font_cache[i] = -1;
    }

  if (fd != -1)
    {
      umlaut = sharp_s = 0;

      if (chr < 0) chr += 256;

      if (chr >= 127)
        {
          for (i = 0; i <= 10; i++)
            {
              if (chr == german[i])
                {
                  chr = ansi[i];
                  if (i < 6)
                    umlaut = 1;
                  else if (i == 6)
                    sharp_s = 1;
                }
            }
          if (chr == 215)
            {
              chr = 'x';
            }
        }
      if (chr < ' ' || chr >= 127) chr = ' ';

      font = abs(font) % 100;
      if (font == 51)
        font = 23; /* fill font */
      else if (font > 23)
        font = 1;

      if (chr == '_')
        {
          if (font < 20) font = 23;
        }
      else if (sharp_s)
        {
          if (font != 23)
            font = s_map[font - 1];
          else
            chr = 126; /* ~ */
        }
      else if (version == GRALGKS)
        {
          if (font == 13 || font == 14)
            {
              for (i = 0; i < 14; i++)
                {
                  if (chr == greek[i])
                    {
                      chr = g_map[i];
                      break;
                    }
                }
            }
          font = gksgralmap[font - 1];
        }

      chr -= ' ';
      offset = ((map[font - 1] - 1) * 95 + chr) * 256;

      if (font_cache[chr] != offset)
        {
          if (lseek(fd, offset, 0) != -1)
            {
              if (gks_read_file(fd, buf, 256) != -1)
                {
                  font_cache[chr] = offset;

                  elptr = bufcache[chr];
                  ebptr = buf;
                  for (i = 0; i < 256; i++) *elptr++ = *ebptr++;
                }
              else
                gks_fatal_error("font file read error");
            }
          else
            gks_fatal_error("font file positioning error");
        }
      memmove((void *)s, (void *)bufcache[chr], 256 * sizeof(int));

      if (umlaut && (s->length < 120 - 20)) s->length += 10;
    }
  else
    {
      gks_fatal_error("can't access font database");
    }
}

void gks_close_font(int fd)
{
  if (fd != -1) gks_close_file(fd);
}
