% MetaUtil, an easier MetaPost life
% Copyright (C) 2005 Ovidiu Gheorghies
%
% This program is free software; you can redistribute it and/or
% modify it 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.
%
% You should have received a copy of the GNU General Public License
% along with this program; if not, write to the Free Software
% Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

if known _util_group_mp:
  expandafter endinput
fi;
_util_group_mp:=1;

input util_object;
input util_commons;
input util_margins;
input util_log;

vardef GroupInfo@#(expr pleft, pright, ptop, pbottom)=
  attributes(@#);
  var(color)   borderColor;
  var(numeric) boxed;

  @#boxed := 0;
  @#borderColor := red;

  Margins.@#(pleft, pright, ptop, pbottom);
enddef;

vardef GroupInfoCopy@#(text src)=
  GroupInfo@#(src.left, src.right, src.top, src.bottom);

  @#boxed := src.boxed;
  @#borderColor := src.borderColor;

enddef;

GroupInfo.iGroup(2, 2, 2, 2);

GroupInfoCopy.iGroupBoxed(iGroup);
iGroupBoxed.boxed := 1;

vardef EGroup@#(text groupInfo)(text objects)=
  ObjectEquations(@#);
  @#className := "Group";

  var(numeric) minx, maxx, miny, maxy;
  var(numeric) nObjects;
  var(string)  objectsAsString;

  GroupInfoCopy.@#info(groupInfo);

  @#objectsAsString := enumToString(objects)("");
  log @#objectsAsString;

  @#nObjects := 0;
  if @#objectsAsString <> "":
    forsuffixes obj = scantokens @#objectsAsString:
        @#nObjects := @#nObjects + 1;
    endfor;
  fi;

enddef;

vardef Group@#(text objects)=
  EGroup@#(iGroup)(objects);
enddef;

vardef Group_layout@#=
  if @#layedout = 0:
    log "Needing layout for group " & (str @#);
    @#layedout := 1;

    if (@#objectsAsString = ""):
      @#width = @#info.left + @#info.right;
      @#height = @#info.top + @#info.bottom;
    else:
      log "Calling layout for objects group '" & (str @#) & "' ...";
      log " object are: '" & @#objectsAsString & "'.";

      layoutObjects(scantokens @#objectsAsString);
      log "All objects in group '" & (str @#) & "' are now layed out.";

      % As already tested, @#objectsAsString must be <> "".
      % See page 53, User's manual for MetaPost
      % "if some of the suffixes are empty, the loop gets
      % executed, with the loop index parameter set to
      % the empty suffix" (!)

      log "Proceeding to finding min/max x/y of objects:";
      log "   " & @#objectsAsString;

      __objectIndex := 0;
      forsuffixes obj__ = scantokens @#objectsAsString:
        if __objectIndex = 0:
            log "First object " & str obj__;
            @#minx := obj__.left;
            log @#maxx;
            log obj__.right;
            @#maxx := obj__.right;
            log @#maxx;
            @#miny := obj__.bottom;
            @#maxy := obj__.top;

            __objectIndex := __objectIndex + 1;
        else:
            log "Current object " & str obj__;

            log "comparing(min)";
            log @#minx;
            log @#obj__.left;
            @#minx := min(@#minx)(obj__.left);

            log "comparing(max)";
            log @#maxx;
            log @#obj__.right;
            @#maxx := max(@#maxx)(obj__.right);

            log "comparing(min)";
            log @#miny;
            log @#obj__.bottom;
            @#miny := min(@#miny)(obj__.bottom);

            log "comparing(max)";
            log @#maxy;
            log @#obj__.top;
            @#maxy := max(@#maxy)(obj__.top);

            __objectIndex := __objectIndex + 1;
        fi;
      endfor;
      log "... done iterating";
      log "maxx = ";
      log @#maxx;

      @#nw = (@#minx - @#info.left, @#maxy + @#info.top);
      @#se = (@#maxx + @#info.right, @#miny - @#info.bottom);

      log "Done performing actual layout for group " & str @#;
    fi;
  else:
    log "NOT needing layout for group " & (str @#);
  fi;
enddef;

vardef Group_draw@#=
  log "Drawing group....";
  Group_layout@#;
  objectEnsurePositioning.@#;

  if @#objectsAsString <> "":
    drawObjects(scantokens @#objectsAsString);
  fi;

  if (@#info.boxed = 1):
    draw objectBox(@#) withcolor @#info.borderColor;
  fi;
enddef;

vardef Group_border@#=
    objectBox(@#)
enddef;