/**************************************************************************
 * 
 * Copyright 2009 VMware, Inc.
 * All Rights Reserved.
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * 
 **************************************************************************/

#include <stdlib.h>
#include "sl_pp_directive.h"
#include "sl_pp_token.h"


static int
_tokenise_identifier(const char **pinput,
                     struct sl_pp_token_info *info)
{
   const char *input = *pinput;
   char identifier[256];   /* XXX: Remove this artifical limit. */
   unsigned int i = 0;

   info->token = SL_PP_IDENTIFIER;
   info->data.identifier = NULL;

   identifier[i++] = *input++;
   while ((*input >= 'a' && *input <= 'z') ||
          (*input >= 'A' && *input <= 'Z') ||
          (*input >= '0' && *input <= '9') ||
          (*input == '_')) {
      if (i >= sizeof(identifier) - 1) {
         return -1;
      }
      identifier[i++] = *input++;
   }
   identifier[i++] = '\0';

   info->data.identifier = malloc(i);
   if (!info->data.identifier) {
      return -1;
   }
   memcpy(info->data.identifier, identifier, i);

   *pinput = input;
   return 0;
}


static int
_tokenise_number(const char **pinput,
                 struct sl_pp_token_info *info)
{
   const char *input = *pinput;
   char number[256];   /* XXX: Remove this artifical limit. */
   unsigned int i = 0;

   info->token = SL_PP_NUMBER;
   info->data.number = NULL;

   number[i++] = *input++;
   while ((*input >= '0' && *input <= '9') ||
          (*input >= 'a' && *input <= 'f') ||
          (*input >= 'A' && *input <= 'F') ||
          (*input == 'x') ||
          (*input == 'X') ||
          (*input == '+') ||
          (*input == '-') ||
          (*input == '.')) {
      if (i >= sizeof(number) - 1) {
         return -1;
      }
      number[i++] = *input++;
   }
   number[i++] = '\0';

   info->data.number = malloc(i);
   if (!info->data.number) {
      return -1;
   }
   memcpy(info->data.number, number, i);

   *pinput = input;
   return 0;
}


int
sl_pp_tokenise(const char *input,
               struct sl_pp_token_info **output)
{
   struct sl_pp_token_info *out = NULL;
   unsigned int out_len = 0;
   unsigned int out_max = 0;

   for (;;) {
      struct sl_pp_token_info info;

      switch (*input) {
      case ' ':
      case '\t':
         input++;
         info.token = SL_PP_WHITESPACE;
         break;

      case '\n':
         input++;
         info.token = SL_PP_NEWLINE;
         break;

      case '#':
         input++;
         info.token = SL_PP_HASH;
         break;

      case ',':
         input++;
         info.token = SL_PP_COMMA;
         break;

      case ';':
         input++;
         info.token = SL_PP_SEMICOLON;
         break;

      case '{':
         input++;
         info.token = SL_PP_LBRACE;
         break;

      case '}':
         input++;
         info.token = SL_PP_RBRACE;
         break;

      case '(':
         input++;
         info.token = SL_PP_LPAREN;
         break;

      case ')':
         input++;
         info.token = SL_PP_RPAREN;
         break;

      case '[':
         input++;
         info.token = SL_PP_LBRACKET;
         break;

      case ']':
         input++;
         info.token = SL_PP_RBRACKET;
         break;

      case '.':
         if (input[1] >= '0' && input[1] <= '9') {
            if (_tokenise_number(&input, &info)) {
               free(out);
               return -1;
            }
         } else {
            input++;
            info.token = SL_PP_DOT;
         }
         break;

      case '+':
         input++;
         if (*input == '+') {
            input++;
            info.token = SL_PP_INCREMENT;
         } else if (*input == '=') {
            input++;
            info.token = SL_PP_ADDASSIGN;
         } else {
            info.token = SL_PP_PLUS;
         }
         break;

      case '-':
         input++;
         if (*input == '-') {
            input++;
            info.token = SL_PP_DECREMENT;
         } else if (*input == '=') {
            input++;
            info.token = SL_PP_SUBASSIGN;
         } else {
            info.token = SL_PP_MINUS;
         }
         break;

      case '~':
         input++;
         info.token = SL_PP_BITNOT;
         break;

      case '!':
         input++;
         if (*input == '=') {
            input++;
            info.token = SL_PP_NOTEQUAL;
         } else {
            info.token = SL_PP_NOT;
         }
         break;

      case '*':
         input++;
         if (*input == '=') {
            input++;
            info.token = SL_PP_MULASSIGN;
         } else {
            info.token = SL_PP_STAR;
         }
         break;

      case '/':
         input++;
         if (*input == '=') {
            input++;
            info.token = SL_PP_DIVASSIGN;
         } else {
            info.token = SL_PP_SLASH;
         }
         break;

      case '%':
         input++;
         if (*input == '=') {
            input++;
            info.token = SL_PP_MODASSIGN;
         } else {
            info.token = SL_PP_MODULO;
         }
         break;

      case '<':
         input++;
         if (*input == '<') {
            input++;
            if (*input == '=') {
               input++;
               info.token = SL_PP_LSHIFTASSIGN;
            } else {
               info.token = SL_PP_LSHIFT;
            }
         } else if (*input == '=') {
            input++;
            info.token = SL_PP_LESSEQUAL;
         } else {
            info.token = SL_PP_LESS;
         }
         break;

      case '>':
         input++;
         if (*input == '>') {
            input++;
            if (*input == '=') {
               input++;
               info.token = SL_PP_RSHIFTASSIGN;
            } else {
               info.token = SL_PP_RSHIFT;
            }
         } else if (*input == '=') {
            input++;
            info.token = SL_PP_GREATEREQUAL;
         } else {
            info.token = SL_PP_GREATER;
         }
         break;

      case '=':
         input++;
         if (*input == '=') {
            input++;
            info.token = SL_PP_EQUAL;
         } else {
            info.token = SL_PP_ASSIGN;
         }
         break;

      case '&':
         input++;
         if (*input == '&') {
            input++;
            info.token = SL_PP_AND;
         } else if (*input == '=') {
            input++;
            info.token = SL_PP_BITANDASSIGN;
         } else {
            info.token = SL_PP_BITAND;
         }
         break;

      case '^':
         input++;
         if (*input == '^') {
            input++;
            info.token = SL_PP_XOR;
         } else if (*input == '=') {
            input++;
            info.token = SL_PP_BITXORASSIGN;
         } else {
            info.token = SL_PP_BITXOR;
         }
         break;

      case '|':
         input++;
         if (*input == '|') {
            input++;
            info.token = SL_PP_OR;
         } else if (*input == '=') {
            input++;
            info.token = SL_PP_BITORASSIGN;
         } else {
            info.token = SL_PP_BITOR;
         }
         break;

      case '?':
         input++;
         info.token = SL_PP_QUESTION;
         break;

      case ':':
         input++;
         info.token = SL_PP_COLON;
         break;

      case '\0':
         info.token = SL_PP_EOF;
         break;

      default:
         if ((*input >= 'a' && *input <= 'z') ||
             (*input >= 'A' && *input <= 'Z') ||
             (*input == '_')) {
            if (_tokenise_identifier(&input, &info)) {
               free(out);
               return -1;
            }
         } else if (*input >= '0' && *input <= '9') {
            if (_tokenise_number(&input, &info)) {
               free(out);
               return -1;
            }
         } else {
            info.data.other = *input++;
            info.token = SL_PP_OTHER;
         }
      }

      if (out_len >= out_max) {
         unsigned int new_max = out_max;

         if (new_max < 0x100) {
            new_max = 0x100;
         } else if (new_max < 0x10000) {
            new_max *= 2;
         } else {
            new_max += 0x10000;
         }

         out = realloc(out, new_max * sizeof(struct sl_pp_token_info));
         if (!out) {
            return -1;
         }
         out_max = new_max;
      }

      out[out_len++] = info;

      if (info.token == SL_PP_EOF) {
         break;
      }
   }

   *output = out;
   return 0;
}