//-----------------------------------------------------------------------------
//
// Copyright © 2016-2017 Project Golan, David Hill
//
// Code by David Hill has been relicensed with consent.
//
// See "LICENSE.lithos3" for more information.
//
//-----------------------------------------------------------------------------
//
// Tokenizer.
//
//-----------------------------------------------------------------------------

#include "Lth_libinfo.h"

#if !LITHOS3_NO_TOKEN

#define _GNU_SOURCE

#include "Lth.h"

#include <ctype.h>
#include <string.h>
#include <ACS_ZDoom.h>


// Extern Functions ----------------------------------------------------------|

//
// Lth_TokenGet
//
void Lth_TokenGet(FILE *fp, Lth_Token *out)
{
   char ch = fgetc(fp);

   out->type = Lth_TOK_EOF;

   if(out->str)
      free(out->str), out->str = NULL;

   switch(ch)
   {
   case '=':  Lth_TokenSet(out, Equals); return;
   case ';':  Lth_TokenSet(out, Semico); return;
   case ',':  Lth_TokenSet(out, Comma ); return;
   case '>':  Lth_TokenSet(out, GT    ); return;
   case '<':  Lth_TokenSet(out, LT    ); return;

   case '[':  Lth_TokenSet(out, BrackO); return;
   case ']':  Lth_TokenSet(out, BrackC); return;
   case '{':  Lth_TokenSet(out, BraceO); return;
   case '}':  Lth_TokenSet(out, BraceC); return;

   case '\n': Lth_TokenSet(out, LnEnd ); return;

   case '-':
      if(isdigit(Lth_fpeekc(fp))) break;
      Lth_TokenSet(out, Minus);
      return;

   case '.':
      if(isdigit(Lth_fpeekc(fp))) break;
      Lth_TokenSet(out, Dot);
      return;
   }

   if(isspace(ch))
   {
      ACS_BeginPrint();

      do ACS_PrintChar(ch);
      while((ch = fgetc(fp)) != EOF && (isspace(ch) && ch != '\n'));
      if(ch != EOF) ungetc(ch, fp);

      out->str  = Lth_strdup_str(ACS_EndStrParam());
      out->type = Lth_TOK_Space;

      return;
   }

   if(ch == '"' || ch == '\'')
   {
      char beg = ch;

      ACS_BeginPrint();

      while((ch = fgetc(fp)) != beg && ch != EOF)
      {
         if(ch == '\\')
         {
            switch((ch = fgetc(fp)))
            {
            case '\\': ACS_PrintChar('\\'); break;
            case 'C':  ACS_PrintChar('\C'); break;
            case 'n':  ACS_PrintChar('\n'); break;
            default: if(ch == beg) ACS_PrintChar(beg); break;
            }
         }
         else
            ACS_PrintChar(ch);
      }

      out->str  = Lth_strdup_str(ACS_EndStrParam());
      out->type = Lth_TOK_String;

      return;
   }

   if(isdigit(ch) || ch == '.' || ch == '-')
   {
      ACS_BeginPrint();

      do ACS_PrintChar(ch);
      while((ch = fgetc(fp)) != EOF && (isalnum(ch) || ch == '.'));
      if(ch != EOF) ungetc(ch, fp);

      out->str  = Lth_strdup_str(ACS_EndStrParam());
      out->type = Lth_TOK_Number;

      return;
   }

   if(Lth_isidenti(ch))
   {
      ACS_BeginPrint();

      do ACS_PrintChar(ch);
      while((ch = fgetc(fp)) != EOF && Lth_isidenti(ch));
      if(ch != EOF) ungetc(ch, fp);

      out->str  = Lth_strdup_str(ACS_EndStrParam());
      out->type = Lth_TOK_Identi;

      return;
   }

   if(ch == EOF)
   {
      Lth_TokenSet(out, EOF);
      return;
   }

   char chrseq[2] = {ch, '\0'};
   out->str  = Lth_strdup(chrseq);
   out->type = Lth_TOK_ChrSeq;
}

//
// Lth_TokenName
//
char const *Lth_TokenName(Lth_TokenType type)
{
   static char const *names[] = {
      "None",
#define Lth_X(name) #name,
#include "Lth_token.h"
      "EOF",
      "Max"
   };
   return names[type];
}

#endif//LITHOS3_NO_TOKEN