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#include "lambda.h"

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include "parser_table_p.h"

class Parser: protected parser_table

{

public:

    union Value {

      int ival;

      // ### more...

    };

public:

    Parser();

    ~Parser();

    bool parse();

protected:

    inline void reallocateStack();

    inline Value &sym(int index)

    { return sym_stack [tos + index - 1]; }

    int nextToken();

    void consumeRule(int ruleno);

protected:

    int tos;

    int stack_size;

    Value *sym_stack;

    int *state_stack;

    int current_char;

    unsigned in_tag: 1;

};

inline void Parser::reallocateStack()

{

    if (! stack_size)

        stack_size = 128;

    else

        stack_size <<= 1;

    sym_stack = reinterpret_cast<Value*> (::realloc(sym_stack, stack_size * sizeof(Value)));

    state_stack = reinterpret_cast<int*> (::realloc(state_stack, stack_size * sizeof(int)));

}

Parser::Parser():

    tos(0),

    stack_size(0),

    sym_stack(0),

    state_stack(0)

{

}

Parser::~Parser()

{

    if (stack_size) {

        ::free(sym_stack);

        ::free(state_stack);

    }

}

bool Parser::parse()

{

  const int INITIAL_STATE = 0;

  current_char = 0;

  in_tag = 0;

  int yytoken = -1;

  reallocateStack();

  tos = 0;

  state_stack[++tos] = INITIAL_STATE;

  while (true)

    {

      if (yytoken == -1 && - TERMINAL_COUNT != action_index [state_stack [tos]])

        yytoken = nextToken();

      int act = t_action (state_stack [tos], yytoken);

      if (act == ACCEPT_STATE) {

        return true;

      }

      else if (act > 0)

        {

          if (++tos == stack_size)

            reallocateStack();

          sym_stack [tos].ival = current_char; // ### save the token value here

          state_stack [tos] = act;

          yytoken = -1;

        }

      else if (act < 0)

        {

          int r = - act - 1;

          tos -= rhs [r];

          act = state_stack [tos++];

          consumeRule (r);

          state_stack [tos] = nt_action (act, lhs [r] - TERMINAL_COUNT);

        }

      else

        break;

    }

    return false;

}

int Parser::nextToken()

{

    static int tokens[] = { ID, ID, ID, EOF_SYMBOL };

    static int *tk = tokens;

    return *tk++;

}

void Parser::consumeRule(int ruleno)

{

    switch (ruleno) {

    case Symbol:

        printf("symbol\n");

        break;

    case SubExpression:

        printf("sub-expr\n");

        break;

    case Appl:

        printf("appl\n");

        break;

    case Abstr:

        printf("abstr\n");

        break;

    }

}

/////////////////////////////

// entry point

/////////////////////////////

int main()

{

    Parser parser;

    if (parser.parse())

        printf ("OK\n");

    else

        printf ("KO\n");

}