common: Put scopeMatch in util, use in highlights

[quassel.git] / src / common / util.cpp

diff --git a/src/common/util.cpp b/src/common/util.cpp
index d9b9d2a..da3ea10 100644 (file)
--- a/src/common/util.cpp
+++ b/src/common/util.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2005-2016 by the Quassel Project                        *
+ *   Copyright (C) 2005-2018 by the Quassel Project                        *
  *   devel@quassel-irc.org                                                 *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -280,3 +280,59 @@ QString formatCurrentDateTimeInString(const QString &formatStr)
 
     return formattedStr;
 }
+
+
+bool scopeMatch(const QString &scopeRule, const QString &string)
+{
+    // A match happens when the string does NOT match ANY inverted rules and matches AT LEAST one
+    // normal rule, unless no normal rules exist (implicit wildcard match).  This gives inverted
+    // rules higher priority regardless of ordering.
+    //
+    // TODO: After switching to Qt 5, use of this should be split into two parts, one part that
+    // would generate compiled QRegularExpressions for match/inverted match, regenerating it on any
+    // rule changes, and another part that would check each message against these compiled rules.
+
+    // Keep track if any matches are found
+    bool matches = false;
+    // Keep track if normal rules and inverted rules are found, allowing for implicit wildcard
+    bool normalRuleFound = false, invertedRuleFound = false;
+
+    // Split each scope rule by separator, ignoring empty parts
+    foreach(QString rule, scopeRule.split(";", QString::SkipEmptyParts)) {
+        // Trim whitespace from the start/end of the rule
+        rule = rule.trimmed();
+        // Ignore empty rules
+        if (rule.isEmpty())
+            continue;
+
+        // Check if this is an inverted rule (starts with '!')
+        if (rule.startsWith("!")) {
+            // Inverted rule found
+            invertedRuleFound = true;
+
+            // Take the reminder of the string
+            QRegExp ruleRx(rule.mid(1), Qt::CaseInsensitive);
+            ruleRx.setPatternSyntax(QRegExp::Wildcard);
+            if (ruleRx.exactMatch(string)) {
+                // Matches an inverted rule, full rule cannot match
+                return false;
+            }
+        } else {
+            // Normal rule found
+            normalRuleFound = true;
+
+            QRegExp ruleRx(rule, Qt::CaseInsensitive);
+            ruleRx.setPatternSyntax(QRegExp::Wildcard);
+            if (ruleRx.exactMatch(string)) {
+                // Matches a normal rule, full rule might match
+                matches = true;
+                // Continue checking in case other inverted rules negate this
+            }
+        }
+    }
+    // No inverted rules matched, okay to match normally
+    // Return true if...
+    // ...we found a normal match
+    // ...implicit wildcard: we had inverted rules (that didn't match) and no normal rules
+    return matches || (invertedRuleFound && !normalRuleFound);
+}