chain.h

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/*
 * Copyright (c) 2003-2025, John Wiegley.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * - Neither the name of New Artisans LLC nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


#pragma once
 
#include "utils.h"
 
namespace ledger {
 
class post_t;
class account_t;
 
template <typename T>
class item_handler : public noncopyable
{
protected:
  shared_ptr<item_handler> handler;
 
public:
  item_handler() {
    TRACE_CTOR(item_handler, "");
  }
  item_handler(shared_ptr<item_handler> _handler) : handler(_handler) {
    TRACE_CTOR(item_handler, "shared_ptr<item_handler>");
  }
  virtual ~item_handler() {
    TRACE_DTOR(item_handler);
  }
 
  virtual void title(const string& str) {
    if (handler)
      handler->title(str);
  }
 
  virtual void flush() {
    if (handler)
      handler->flush();
  }
  virtual void operator()(T& item) {
    if (handler) {
      check_for_signal();
      (*handler)(item);
    }
  }
 
  virtual void clear() {
    if (handler)
      handler->clear();
  }
};
 
typedef shared_ptr<item_handler<post_t> > post_handler_ptr;
typedef shared_ptr<item_handler<account_t> > acct_handler_ptr;
 
class report_t;
 
post_handler_ptr
chain_pre_post_handlers(post_handler_ptr base_handler,
                        report_t&        report);
 
post_handler_ptr
chain_post_handlers(post_handler_ptr base_handler,
                    report_t&        report,
                    bool             for_accounts_report = false);
 
inline post_handler_ptr
chain_handlers(post_handler_ptr handler,
               report_t&        report,
               bool             for_accounts_report = false) {
  handler = chain_post_handlers(handler, report, for_accounts_report);
  handler = chain_pre_post_handlers(handler, report);
  return handler;
}
 
} // namespace ledger