moved filter stuff from card list here

src/data/filter.hpp

+//+----------------------------------------------------------------------------+
+//| Description:  Magic Set Editor - Program to make Magic (tm) cards          |
+//| Copyright:    (C) 2001 - 2010 Twan van Laarhoven and Sean Hunt             |
+//| License:      GNU General Public License 2 or later (see file COPYING)     |
+//+----------------------------------------------------------------------------+
+
+#ifndef HEADER_DATA_FILTER
+#define HEADER_DATA_FILTER
+
+// ----------------------------------------------------------------------------- : Includes
+
+#include <util/prec.hpp>
+
+// ----------------------------------------------------------------------------- : Filters
+
+/// A filter function to determine which items are shown in a list
+template <typename T>
+class Filter : public IntrusivePtrVirtualBase {
+  public:
+	typedef intrusive_ptr<T> TP;
+	
+	virtual ~Filter() {}
+	/// Should an object be shown in the list?
+	virtual bool keep(T const& x) const {
+		return false;
+	}
+	/// Select objects from a list
+	virtual void getItems(vector<TP> const& in, vector<VoidP>& out) const {
+		for (vector<TP>::const_iterator it = in.begin() ; it != in.end() ; ++it) {
+			if (keep(**it)) {
+				out.push_back(*it);
+			}
+		}
+	}
+};
+
+// ----------------------------------------------------------------------------- : Quick search
+
+/// Does the given object match the quick search query?
+template <typename T>
+bool match_quicksearch_query(String const& query, T const& object) {
+	bool need_match = true;
+	// iterate over the components of the query
+	for (size_t i = 0 ; i < query.size() ; ) {
+		if (query.GetChar(i) == _(' ')) {
+			// skip spaces
+			i++;
+		} else if (query.GetChar(i) == _('-')) {
+			// negate the next query, i.e. match only if it is not on the card
+			need_match = !need_match;
+			i++;
+		} else {
+			size_t end, next;
+			if (query.GetChar(i) == _('"')) {
+				// quoted string, match exactly
+				i++;
+				end =query.find_first_of(_('"'),i);
+				next = min(end,query.size()) + 1;
+			} else {
+				// single word
+				next = end = query.find_first_of(_(' '),i);
+			}
+			bool match = object.contains(query.substr(i,end-i));
+			if (match != need_match) {
+				return false;
+			}
+			need_match = true; // next word is no longer negated
+			i = next;
+		}
+	}
+	return true;
+}
+
+/// A filter function that searches for objects containing a string
+template <typename T>
+class QuickFilter : public Filter<T> {
+  public:
+	using typename Filter<T>::TP;
+	QuickFilter(String const& query) : query(query) {}
+	virtual bool keep(T const& x) const {
+		return match_quicksearch_query(query, x);
+	}
+  private:
+	String query;
+};
+
+// ----------------------------------------------------------------------------- : EOF
+#endif