format.h

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/*
 * Copyright (c) 2003-2023, 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 "expr.h"
#include "unistring.h"
 
#include <boost/smart_ptr/scoped_ptr.hpp>
 
namespace ledger {
 
class unistring;
 
DECLARE_EXCEPTION(format_error, std::runtime_error);
 
class format_t : public expr_base_t<string>, public noncopyable
{
  typedef expr_base_t<string> base_type;
 
  struct element_t : public flags::supports_flags<>, public noncopyable
  {
#define ELEMENT_ALIGN_LEFT 0x01
 
    enum kind_t { STRING, EXPR };
 
    kind_t                       type;
    std::size_t                  min_width;
    std::size_t                  max_width;
    variant<string, expr_t>      data;
    scoped_ptr<struct element_t> next;
 
    element_t() throw()
      : supports_flags<>(), type(STRING), min_width(0), max_width(0) {
      TRACE_CTOR(element_t, "");
    }
    ~element_t() throw() {
      TRACE_DTOR(element_t);
    }
 
    element_t& operator=(const element_t& elem) {
      if (this != &elem) {
        supports_flags<>::operator=(elem);
        type      = elem.type;
        min_width = elem.min_width;
        max_width = elem.max_width;
        data      = elem.data;
      }
      return *this;
    }
 
    friend inline void mark_red(std::ostream& out, const element_t * elem) {
      out.setf(std::ios::left);
      out.width(0);
      out << "\033[31m";
 
      if (elem->has_flags(ELEMENT_ALIGN_LEFT))
        out << std::left;
      else
        out << std::right;
 
      if (elem->min_width > 0)
        out.width(static_cast<std::streamsize>(elem->min_width));
    }
 
    void dump(std::ostream& out) const;
  };
 
  scoped_ptr<element_t> elements;
 
public:
  static enum elision_style_t {
    TRUNCATE_TRAILING,
    TRUNCATE_MIDDLE,
    TRUNCATE_LEADING,
    ABBREVIATE
  } default_style;
 
  static bool default_style_changed;
 
private:
  static element_t * parse_elements(const string& fmt,
                                    const optional<format_t&>& tmpl);
 
public:
  format_t() : base_type() {
    TRACE_CTOR(format_t, "");
  }
  format_t(const string& _str, scope_t * context = NULL)
    : base_type(context) {
    if (! _str.empty())
      parse_format(_str);
    TRACE_CTOR(format_t, "const string&");
  }
  virtual ~format_t() {
    TRACE_DTOR(format_t);
  }
 
  void parse_format(const string& _format,
                    const optional<format_t&>& tmpl = none) {
    elements.reset(parse_elements(_format, tmpl));
    set_text(_format);
  }
 
  virtual void mark_uncompiled() {
    for (element_t * elem = elements.get(); elem; elem = elem->next.get()) {
      if (elem->type == element_t::EXPR) {
        expr_t& expr(boost::get<expr_t>(elem->data));
        expr.mark_uncompiled();
      }
    }
  }
 
  virtual result_type real_calc(scope_t& scope);
 
  virtual void dump(std::ostream& out) const {
    for (const element_t * elem = elements.get();
         elem;
         elem = elem->next.get())
      elem->dump(out);
  }
 
  static string truncate(const unistring&  str,
                         const std::size_t width,
                         const std::size_t account_abbrev_length = 0);
};
 
} // namespace ledger