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/*

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 * (c) 2009 Mario de Sousa

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 *

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 * Offered to the public under the terms of the GNU General Public License

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 * as published by the Free Software Foundation; either version 2 of the

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 * License, or (at your option) any later version.

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 *

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 * This program is distributed in the hope that it will be useful, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

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 * Public License for more details.

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

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 */

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/*

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 * An IEC 61131-3 IL and ST compiler.

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 *

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 * Based on the

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 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

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 *

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 */

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/*

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 * Iterate through all declared functions and Function Blocks, 

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 * and, for each function/FB, add a declaration of the EN and ENO 

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 * parameters, if they have not already been explicitly declared.

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 *

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 * EN and ENO parameters declared explicitly (by the user in the source code)

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 * and implicitly (by the comnpiler, i.e. by this visitor class) may be

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 * distinguished later on by the 'method' flag in the en_param_declaration_c

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 * and eno_param_declaration_c objects.

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 */

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#include "../absyntax/visitor.hh"

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class add_en_eno_param_decl_c : public null_visitor_c {

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  public:

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    static symbol_c *add_to(symbol_c *tree_root);

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    ~add_en_eno_param_decl_c(void);

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  private:

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    /* this class is a singleton. So we need a pointer to the single instance... */

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    static add_en_eno_param_decl_c *singleton;

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    /* flags to remember whether the EN and/or ENO parameters have already

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     * been explicitly declared by the user in the IEC 61131-3 source code we are parsing...

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     */

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    bool en_declared;

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    bool eno_declared;

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  private:

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    void* iterate_list(list_c *list);

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    input_declarations_c  *build_en_param (void);

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    output_declarations_c *build_eno_param(void);

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  private:

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    /***************************/

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    /* B 0 - Programming Model */

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    /***************************/

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    void *visit(library_c *symbol);

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    /***********************/

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    /* B 1.5.1 - Functions */

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    /***********************/

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    void *visit(function_declaration_c *symbol);

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    /* intermediate helper symbol for function_declaration */

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    void *visit(var_declarations_list_c *symbol);

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    /******************************************/

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    /* B 1.4.3 - Declaration & Initialisation */

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    /******************************************/

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    void *visit(input_declarations_c *symbol);

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    void *visit(input_declaration_list_c *symbol);

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    void *visit(en_param_declaration_c *symbol);

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    void *visit(eno_param_declaration_c *symbol);

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    void *visit(output_declarations_c *symbol);

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    void *visit(var_init_decl_list_c *symbol);

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    /*****************************/

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    /* B 1.5.2 - Function Blocks */

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    /*****************************/

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    /*  FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */

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    void *visit(function_block_declaration_c *symbol);

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}; // function_param_iterator_c

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