src/format.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2008-2017 by Andrzej Rybczak                            *
   3  *   electricityispower@gmail.com                                          *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
  19  ***************************************************************************/
  20
  21 #include <stdexcept>
  22
  23 #include "format_impl.h"
  24 #include "utility/type_conversions.h"
  25
  26 namespace {
  27
  28 const unsigned properties = Format::Flags::Color
  29                           | Format::Flags::Format
  30                           | Format::Flags::OutputSwitch;
  31
  32 template <typename CharT> using string = std::basic_string<CharT>;
  33 template <typename CharT> using iterator = typename std::basic_string<CharT>::const_iterator;
  34 template <typename CharT> using expressions = std::vector<Format::Expression<CharT>>;
  35
  36 template <typename CharT>
  37 std::string invalidCharacter(CharT c)
  38 {
  39         return "invalid character '"
  40              + convertString<char, CharT>::apply(boost::lexical_cast<string<CharT>>(c))
  41              + "'";
  42 }
  43
  44 template <typename CharT>
  45 void throwError(const string<CharT> &s, iterator<CharT> current, std::string msg)
  46 {
  47         throw std::runtime_error(
  48                 std::move(msg) + " at position " + boost::lexical_cast<std::string>(current - s.begin())
  49         );
  50 }
  51
  52 template <typename CharT>
  53 void rangeCheck(const string<CharT> &s, iterator<CharT> current, iterator<CharT> end)
  54 {
  55         if (current >= end)
  56                 throwError(s, current, "unexpected end");
  57 }
  58
  59 template <typename CharT>
  60 expressions<CharT> parseBracket(const string<CharT> &s,
  61                                 iterator<CharT> it, iterator<CharT> end,
  62                                 const unsigned flags)
  63 {
  64         string<CharT> token;
  65         expressions<CharT> tmp, result;
  66         auto push_token = [&] {
  67                 if (!token.empty())
  68                         result.push_back(std::move(token));
  69         };
  70         for (; it != end; ++it)
  71         {
  72                 if (*it == '{')
  73                 {
  74                         push_token();
  75                         bool done;
  76                         Format::FirstOf<CharT> first_of;
  77                         do
  78                         {
  79                                 auto jt = it;
  80                                 done = true;
  81                                 // get to the corresponding closing bracket
  82                                 unsigned brackets = 1;
  83                                 while (brackets > 0)
  84                                 {
  85                                         if (++jt == end)
  86                                                 break;
  87                                         if (*jt == '{')
  88                                                 ++brackets;
  89                                         else if (*jt == '}')
  90                                                 --brackets;
  91                                 }
  92                                 // check if we're still in range
  93                                 rangeCheck(s, jt, end);
  94                                 // skip the opening bracket
  95                                 ++it;
  96                                 // recursively parse the bracket
  97                                 tmp = parseBracket(s, it, jt, flags);
  98                                 // if the inner bracket contains only one expression,
  99                                 // put it as is. otherwise make a group out of them.
 100                                 if (tmp.size() == 1)
 101                                         first_of.base().push_back(std::move(tmp[0]));
 102                                 else
 103                                         first_of.base().push_back(Format::Group<CharT>(std::move(tmp)));
 104                                 it = jt;
 105                                 // check for the alternative
 106                                 ++jt;
 107                                 if (jt != end && *jt == '|')
 108                                 {
 109                                         ++jt;
 110                                         rangeCheck(s, jt, end);
 111                                         if (*jt != '{')
 112                                                 throwError(s, jt, invalidCharacter(*jt) + ", expected '{'");
 113                                         it = jt;
 114                                         done = false;
 115                                 }
 116                         }
 117                         while (!done);
 118                         assert(!first_of.base().empty());
 119                         result.push_back(std::move(first_of));
 120                 }
 121                 else if (flags & Format::Flags::Tag && *it == '%')
 122                 {
 123                         ++it;
 124                         rangeCheck(s, it, end);
 125                         // %% is escaped %
 126                         if (*it == '%')
 127                         {
 128                                 token += '%';
 129                                 continue;
 130                         }
 131                         push_token();
 132                         // check for tag delimiter
 133                         unsigned delimiter = 0;
 134                         if (isdigit(*it))
 135                         {
 136                                 string<CharT> sdelimiter;
 137                                 do
 138                                         sdelimiter += *it++;
 139                                 while (it != end && isdigit(*it));
 140                                 rangeCheck(s, it, end);
 141                                 delimiter = boost::lexical_cast<unsigned>(sdelimiter);
 142                         }
 143                         auto f = charToGetFunction(*it);
 144                         if (f == nullptr)
 145                                 throwError(s, it, invalidCharacter(*it));
 146                         result.push_back(Format::SongTag(f, delimiter));
 147                 }
 148                 else if (flags & properties && *it == '$')
 149                 {
 150                         ++it;
 151                         rangeCheck(s, it, end);
 152                         // $$ is escaped $
 153                         if (*it == '$')
 154                         {
 155                                 token += '$';
 156                                 continue;
 157                         }
 158                         push_token();
 159                         // legacy colors
 160                         if (flags & Format::Flags::Color && isdigit(*it))
 161                         {
 162                                 auto color = charToColor(*it);
 163                                 result.push_back(color);
 164                         }
 165                         // new colors
 166                         else if (flags & Format::Flags::Color && *it == '(')
 167                         {
 168                                 ++it;
 169                                 rangeCheck(s, it, end);
 170                                 auto jt = it;
 171                                 string<CharT> scolor;
 172                                 do
 173                                         scolor += *it++;
 174                                 while (it != end && *it != ')');
 175                                 rangeCheck(s, it, end);
 176                                 auto value = convertString<char, CharT>::apply(scolor);
 177                                 try {
 178                                         result.push_back(boost::lexical_cast<NC::Color>(value));
 179                                 } catch (boost::bad_lexical_cast &) {
 180                                         throwError(s, jt, "invalid color \"" + value + "\"");
 181                                 }
 182                         }
 183                         // output switch
 184                         else if (flags & Format::Flags::OutputSwitch && *it == 'R')
 185                                 result.push_back(Format::OutputSwitch());
 186                         // format
 187                         else if (flags & Format::Flags::Format && *it == 'b')
 188                                 result.push_back(NC::Format::Bold);
 189                         else if (flags & Format::Flags::Format && *it == 'u')
 190                                 result.push_back(NC::Format::Underline);
 191                         else if (flags & Format::Flags::Format && *it == 'a')
 192                                 result.push_back(NC::Format::AltCharset);
 193                         else if (flags & Format::Flags::Format && *it == 'r')
 194                                 result.push_back(NC::Format::Reverse);
 195                         else if (flags & Format::Flags::Format && *it == '/')
 196                         {
 197                                 ++it;
 198                                 rangeCheck(s, it, end);
 199                                 if (*it == 'b')
 200                                         result.push_back(NC::Format::NoBold);
 201                                 else if (*it == 'u')
 202                                         result.push_back(NC::Format::NoUnderline);
 203                                 else if (*it == 'a')
 204                                         result.push_back(NC::Format::NoAltCharset);
 205                                 else if (*it == 'r')
 206                                         result.push_back(NC::Format::NoReverse);
 207                                 else
 208                                         throwError(s, it, invalidCharacter(*it));
 209                         }
 210                         else
 211                                 throwError(s, it, invalidCharacter(*it));
 212                 }
 213                 else
 214                         token += *it;
 215         }
 216         push_token();
 217         return result;
 218 }
 219
 220 }
 221
 222 namespace Format {
 223
 224 AST<char> parse(const std::string &s, const unsigned flags)
 225 {
 226         return AST<char>(parseBracket(s, s.begin(), s.end(), flags));
 227 }
 228
 229 AST<wchar_t> parse(const std::wstring &s, const unsigned flags)
 230 {
 231         return AST<wchar_t>(parseBracket(s, s.begin(), s.end(), flags));
 232 }
 233
 234 }