/*
 * (c) 2003 Mario de Sousa
 *
 * Offered to the public 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.
 *
 * This code is made available on the understanding that it will not be
 * used in safety-critical situations without a full and competent review.
 */

/*
 * An IEC 61131-3 IL and ST compiler.
 *
 * Based on the
 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
 *
 */


/*
 * Function parameter iterator.
 * Iterate through the in/out parameters of a function declaration.
 * Function blocks are also suported.
 *
 * This is part of the 4th stage that generates
 * a c++ source program equivalent to the IL and ST
 * code.
 */

/* Given a function_declaration_c, iterate through each
 * function in/out/inout parameter, returning the name
 * of each parameter...function_param_iterator_c
 */



#include "function_param_iterator.hh"
#include "spec_init_separator.hh"
#include <strings.h>


//#define DEBUG
#ifdef DEBUG
#define TRACE(classname) printf("\n____%s____\n",classname);
#else
#define TRACE(classname)
#endif


#define ERROR error_exit(__FILE__,__LINE__)
/* function defined in main.cc */
extern void error_exit(const char *file_name, int line_no);



void* function_param_iterator_c::handle_param_list(list_c *list) {
  if (next_param <= param_count + list->n)
    return list->elements[next_param - param_count - 1];

  /* the desired param is not on this list... */
  param_count += list->n;
 return NULL;
}

void* function_param_iterator_c::handle_single_param(symbol_c *var_name) {
  param_count++;
  if (next_param == param_count)
    return var_name;

  /* not yet the desired param... */
 return NULL;
}

void* function_param_iterator_c::iterate_list(list_c *list) {
  void *res;
  for (int i = 0; i < list->n; i++) {
    res = list->elements[i]->accept(*this);
    if (res != NULL)
        return res;
  }
  return NULL;
}

/* start off at the first parameter once again... */
void function_param_iterator_c::reset(void) {
  next_param = param_count = 0;
  current_param_name = NULL;
  current_param_type = current_param_default_value = NULL;
  en_declared = false;
  eno_declared = false;
}

/* initialise the iterator object.
 * We must be given a reference to the function declaration
 * that will be analysed...
 */
function_param_iterator_c::function_param_iterator_c(function_declaration_c *f_decl) {
  this->f_decl = f_decl;
  reset();
}

/* initialise the iterator object.
 * We must be given a reference to the function block declaration
 * that will be analysed...
 */
function_param_iterator_c::function_param_iterator_c(function_block_declaration_c *fb_decl) {
  this->f_decl = fb_decl;
  reset();
}

/* initialise the iterator object.
 * We must be given a reference to the program declaration
 * that will be analysed...
 */
function_param_iterator_c::function_param_iterator_c(program_declaration_c *p_decl) {
  this->f_decl = p_decl;
  reset();
}

/* Skip to the next parameter. After object creation,
 * the object references on parameter _before_ the first, so
 * this function must be called once to get the object to
 * reference the first parameter...
 *
 * Returns the parameter's name!
 */
identifier_c *function_param_iterator_c::next(void) {
  void *res;
  identifier_c *identifier;
  param_count = 0;
  next_param++;
  res = f_decl->accept(*this);
  if (res != NULL) {
    symbol_c *sym = (symbol_c *)res;
    identifier = dynamic_cast<identifier_c *>(sym);
    if (identifier == NULL)
      ERROR;
  }
  else if (!en_declared) {
    current_param_direction = direction_in;
    identifier = declare_en_param();
  }
  else if (!eno_declared) {
    current_param_direction = direction_out;
    identifier = declare_eno_param();
  }
  else
    return NULL;
  
  current_param_name = identifier;
  return current_param_name;
}

identifier_c *function_param_iterator_c::declare_en_param(void) {
  en_declared = true;
  identifier_c *identifier = new identifier_c("EN");
  current_param_type = (symbol_c*)(new bool_type_name_c());
  current_param_default_value = (symbol_c*)(new boolean_literal_c(current_param_type, new boolean_true_c()));
  return identifier;
}

identifier_c *function_param_iterator_c::declare_eno_param(void) {
  eno_declared = true;
  identifier_c *identifier = new identifier_c("ENO");
  current_param_type = (symbol_c*)(new bool_type_name_c());
  current_param_default_value = NULL;
  return identifier;
}

/* Returns the currently referenced parameter's default value,
 * or NULL if none is specified in the function declrataion itself.
 */
symbol_c *function_param_iterator_c::default_value(void) {
  return current_param_default_value;
}

/* Returns the currently referenced parameter's type name. */
symbol_c *function_param_iterator_c::param_type(void) {
  return current_param_type;
}

/* Returns the currently referenced parameter's data passing direction.
 * i.e. VAR_INPUT, VAR_OUTPUT or VAR_INOUT
 */
function_param_iterator_c::param_direction_t function_param_iterator_c::param_direction(void) {
  return current_param_direction;
}

/****************************************/
/* 1.4.3 - Declaration & Initialisation */
/****************************************/
void *function_param_iterator_c::visit(input_declarations_c *symbol) {
  TRACE("input_declarations_c");
  current_param_direction = direction_in;
  return symbol->input_declaration_list->accept(*this);
}

void *function_param_iterator_c::visit(input_declaration_list_c *symbol) {TRACE("input_declaration_list_c"); return iterate_list(symbol);}

void *function_param_iterator_c::visit(edge_declaration_c *symbol) {TRACE("edge_declaration_c"); return symbol->var1_list->accept(*this);}

void *function_param_iterator_c::visit(en_param_declaration_c *symbol) {
  TRACE("en_param_declaration_c");
  if (en_declared) ERROR;
  return (void *)declare_en_param();
}

/* var1_list ':' array_spec_init */
//SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)
void *function_param_iterator_c::visit(array_var_init_decl_c *symbol) {TRACE("array_var_init_decl_c"); return symbol->var1_list->accept(*this);}

/*  var1_list ':' initialized_structure */
//SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)
void *function_param_iterator_c::visit(structured_var_init_decl_c *symbol) {TRACE("structured_var_init_decl_c"); return symbol->var1_list->accept(*this);}

void *function_param_iterator_c::visit(output_declarations_c *symbol) {
  TRACE("output_declarations_c");
  current_param_direction = direction_out;
  return symbol->var_init_decl_list->accept(*this);
}
void *function_param_iterator_c::visit(eno_param_declaration_c *symbol) {
  TRACE("eno_param_declaration_c");
  if (eno_declared) ERROR;
  return (void *)declare_eno_param();
}
void *function_param_iterator_c::visit(input_output_declarations_c *symbol) {
  TRACE("input_output_declarations_c");
  current_param_direction = direction_inout;
  return symbol->var_declaration_list->accept(*this);
}
void *function_param_iterator_c::visit(var_declaration_list_c *symbol) {TRACE("var_declaration_list_c"); return iterate_list(symbol);}

/*  var1_list ':' array_specification */
//SYM_REF2(array_var_declaration_c, var1_list, array_specification)
void *function_param_iterator_c::visit(array_var_declaration_c *symbol) {TRACE("array_var_declaration_c"); return symbol->var1_list->accept(*this);}

/*  var1_list ':' structure_type_name */
//SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)
void *function_param_iterator_c::visit(structured_var_declaration_c *symbol) {TRACE("structured_var_declaration_c"); return symbol->var1_list->accept(*this);}

/* VAR [CONSTANT] var_init_decl_list END_VAR */
void *function_param_iterator_c::visit(var_declarations_c *symbol) {TRACE("var_declarations_c"); return NULL;}

/*| VAR_EXTERNAL [CONSTANT] external_declaration_list END_VAR */
/* option -> may be NULL ! */
// SYM_REF2(external_var_declarations_c, option, external_declaration_list)
void *function_param_iterator_c::visit(external_var_declarations_c *symbol) {
  TRACE("external_var_declarations_c");
  current_param_direction = direction_extref;
  return symbol->external_declaration_list->accept(*this);
}

/* helper symbol for external_var_declarations */
/*| external_declaration_list external_declaration';' */
// SYM_LIST(external_declaration_list_c)
void *function_param_iterator_c::visit(external_declaration_list_c *symbol) {TRACE("external_declaration_list_c"); return iterate_list(symbol);}

/*  global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */
//SYM_REF2(external_declaration_c, global_var_name, specification)
void *function_param_iterator_c::visit(external_declaration_c *symbol) {
  TRACE("external_declaration_c");
  /* It is OK to store these values in the current_param_XXX
   * variables, because if the desired parameter is not in the
   * variable list we will be analysing, the current_param_XXXX
   * variables will get overwritten when we visit the next
   * var1_init_decl_c list!
   */
  current_param_default_value = spec_init_sperator_c::get_init(symbol->specification);
  current_param_type = spec_init_sperator_c::get_spec(symbol->specification);

  return handle_single_param(symbol->global_var_name);
}


#if 0
/*| VAR_GLOBAL [CONSTANT|RETAIN] global_var_decl_list END_VAR */
/* option -> may be NULL ! */
SYM_REF2(global_var_declarations_c, option, global_var_decl_list)

/* helper symbol for global_var_declarations */
/*| global_var_decl_list global_var_decl ';' */
SYM_LIST(global_var_decl_list_c)

/*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */
/* type_specification ->may be NULL ! */
SYM_REF2(global_var_decl_c, global_var_spec, type_specification)

/*| global_var_name location */
SYM_REF2(global_var_spec_c, global_var_name, location)

/*  AT direct_variable */
SYM_REF2(location_c, direct_variable, unused)

/*| global_var_list ',' global_var_name */
SYM_LIST(global_var_list_c)

/*  var1_list ':' single_byte_string_spec */
SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)

/*  STRING ['[' integer ']'] [ASSIGN single_byte_character_string] */
/* integer ->may be NULL ! */
/* single_byte_character_string ->may be NULL ! */
SYM_REF2(single_byte_string_spec_c, integer, single_byte_character_string)

/*  var1_list ':' double_byte_string_spec */
SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)

/*  WSTRING ['[' integer ']'] [ASSIGN double_byte_character_string] */
/* integer ->may be NULL ! */
/* double_byte_character_string ->may be NULL ! */
SYM_REF2(double_byte_string_spec_c, integer, double_byte_character_string)

/*| VAR [RETAIN|NON_RETAIN] incompl_located_var_decl_list END_VAR */
/* option ->may be NULL ! */
SYM_REF2(incompl_located_var_declarations_c, option, incompl_located_var_decl_list)

/* helper symbol for incompl_located_var_declarations */
/*| incompl_located_var_decl_list incompl_located_var_decl ';' */
SYM_LIST(incompl_located_var_decl_list_c)

/*  variable_name incompl_location ':' var_spec */
SYM_REF4(incompl_located_var_decl_c, variable_name, incompl_location, var_spec, unused)

/*  AT incompl_location_token */
SYM_TOKEN(incompl_location_c)
#endif


void *function_param_iterator_c::visit(var1_init_decl_c *symbol) {
  TRACE("var1_init_decl_c");
  /* It is OK to store these values in the current_param_XXX
   * variables, because if the desired parameter is not in the
   * variable list we will be analysing, the current_param_XXXX
   * variables will get overwritten when we visit the next
   * var1_init_decl_c list!
   */
  current_param_default_value = spec_init_sperator_c::get_init(symbol->spec_init);
  current_param_type = spec_init_sperator_c::get_spec(symbol->spec_init);

  return symbol->var1_list->accept(*this);
}



void *function_param_iterator_c::visit(var1_list_c *symbol) {
  TRACE("var1_list_c");
  return handle_param_list(symbol);
}

void *function_param_iterator_c::visit(var_init_decl_list_c *symbol) {TRACE("var_init_decl_list_c"); return iterate_list(symbol);}


/***********************/
/* B 1.5.1 - Functions */
/***********************/
void *function_param_iterator_c::visit(function_declaration_c *symbol) {TRACE("function_declaration_c"); return symbol->var_declarations_list->accept(*this);}
/* intermediate helper symbol for function_declaration */
void *function_param_iterator_c::visit(var_declarations_list_c *symbol) {TRACE("var_declarations_list_c"); return iterate_list(symbol);}
void *function_param_iterator_c::visit(function_var_decls_c *symbol) {TRACE("function_var_decls_c"); /* ignore */ return NULL;}


/*****************************/
/* B 1.5.2 - Function Blocks */
/*****************************/
/*  FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
void *function_param_iterator_c::visit(function_block_declaration_c *symbol) {TRACE("function_block_declaration_c"); return symbol->var_declarations->accept(*this);}

/* intermediate helper symbol for function_declaration */
/*  { io_var_declarations | other_var_declarations }   */
/*
 * NOTE: we re-use the var_declarations_list_c
 */

/*  VAR_TEMP temp_var_decl_list END_VAR */
void *function_param_iterator_c::visit(temp_var_decls_c *symbol) {TRACE("temp_var_decls_c"); /* ignore */ return NULL;}
void *function_param_iterator_c::visit(temp_var_decls_list_c *symbol) {TRACE("temp_var_decls_list_c"); /* ignore */ return NULL;}

/*  VAR NON_RETAIN var_init_decl_list END_VAR */
void *function_param_iterator_c::visit(non_retentive_var_decls_c *symbol) {TRACE("non_retentive_var_decls_c"); /* ignore */ return NULL;}


/**********************/
/* B 1.5.3 - Programs */
/**********************/
/*  PROGRAM program_type_name program_var_declarations_list function_block_body END_PROGRAM */
// SYM_REF4(program_declaration_c, program_type_name, var_declarations, function_block_body, unused)
void *function_param_iterator_c::visit(program_declaration_c *symbol) {TRACE("program_declaration_c"); return symbol->var_declarations->accept(*this);}

/* intermediate helper symbol for program_declaration_c */
/*  { io_var_declarations | other_var_declarations }   */
/*
 * NOTE: we re-use the var_declarations_list_c
 */