(svn r24337) -Feature: Allow filtering for multiple words (separated by whitespace resp. quoted) in the sign list, content- and NewGRF-guis.

1 files changed, 72 insertions, 0 deletions

diff --git a/src/stringfilter_type.h b/src/stringfilter_type.h
new file mode 100644
index 000000000..7995ffdf6
--- /dev/null
+++ b/src/stringfilter_type.h
@@ -0,0 +1,72 @@
+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD 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, version 2.
+ * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file stringfilter_type.h Searching and filtering using a stringterm. */
+
+#ifndef STRINGFILTER_TYPE_H
+#define STRINGFILTER_TYPE_H
+
+#include "core/smallvec_type.hpp"
+
+/**
+ * String filter and state.
+ *
+ * The filter takes a stringterm and parses it into words separated by whitespace.
+ * The whitespace-separation can be avoided by quoting words in the searchterm using " or '.
+ * The quotation characters can be nested or concatenated in a unix-shell style.
+ *
+ * When filtering an item, all words are checked for matches, and the filter matches if every word
+ * matched. So, effectively this is a AND search for all entered words.
+ *
+ * Once the filter is set up using SetFilterTerm, multiple items can be filtered consecutively.
+ *  1. For every item first call ResetState() which resets the matching-state.
+ *  2. Pass all lines of the item via AddLine() to the filter.
+ *  3. Check the matching-result for the item via GetState().
+ */
+struct StringFilter {
+private:
+	/** State of a single filter word */
+	struct WordState {
+		const char *start;                         ///< Word to filter for.
+		bool match;                                ///< Already matched?
+	};
+
+	const char *filter_buffer;                     ///< Parsed filter string. Words separated by 0.
+	SmallVector<WordState, 4> word_index;          ///< Word index and filter state.
+	uint word_matches;                             ///< Summary of filter state: Number of words matched.
+
+	const bool *case_sensitive;                    ///< Match case-sensitively (usually a static variable).
+
+public:
+	/**
+	 * Constructor for filter.
+	 * @param case_sensitive Pointer to a (usually static) variable controlling the case-sensitivity. NULL means always case-insensitive.
+	 */
+	StringFilter(const bool *case_sensitive = NULL) : filter_buffer(NULL), word_matches(0), case_sensitive(case_sensitive) {}
+	~StringFilter() { free(this->filter_buffer); }
+
+	void SetFilterTerm(const char *str);
+
+	/**
+	 * Check whether any filter words were entered.
+	 * @return true if no words were entered.
+	 */
+	bool IsEmpty() const { return this->word_index.Length() == 0; }
+
+	void ResetState();
+	void AddLine(const char *str);
+
+	/**
+	 * Get the matching state of the current item.
+	 * @return true if matched.
+	 */
+	bool GetState() const { return this->word_matches == this->word_index.Length(); }
+};
+
+#endif /* STRINGFILTER_TYPE_H */