1 files changed, 107 insertions, 0 deletions
diff --git a/mailnews/base/search/public/nsMsgSearchBoolExpression.h b/mailnews/base/search/public/nsMsgSearchBoolExpression.h
new file mode 100644
index 000000000..c65e5c24a
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+++ b/mailnews/base/search/public/nsMsgSearchBoolExpression.h
@@ -0,0 +1,107 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsMsgSearchCore.h"
+
+#ifndef __nsMsgSearchBoolExpression_h
+#define __nsMsgSearchBoolExpression_h
+
+//-----------------------------------------------------------------------------
+// nsMsgSearchBoolExpression is a class added to provide AND/OR terms in search queries.
+//  A nsMsgSearchBoolExpression contains either a search term or two nsMsgSearchBoolExpressions and
+//    a boolean operator.
+// I (mscott) am placing it here for now....
+//-----------------------------------------------------------------------------
+
+/* CBoolExpression --> encapsulates one or more search terms by internally
+   representing the search terms and their boolean operators as a binary
+   expression tree. Each node in the tree consists of either
+     (1) a boolean operator and two nsMsgSearchBoolExpressions or
+     (2) if the node is a leaf node then it contains a search term.
+   With each search term that is part of the expression we may also keep
+   a character string. The character
+   string is used to store the IMAP/NNTP encoding of the search term. This
+   makes generating a search encoding (for online) easier.
+
+   For IMAP/NNTP: nsMsgSearchBoolExpression has/assumes knowledge about how
+   AND and OR search terms are combined according to IMAP4 and NNTP protocol.
+   That is the only piece of IMAP/NNTP knowledge it is aware of.
+
+   Order of Evaluation: Okay, the way in which the boolean expression tree
+   is put together directly effects the order of evaluation. We currently
+   support left to right evaluation.
+   Supporting other order of evaluations involves adding new internal add
+   term methods.
+ */
+
+class nsMsgSearchBoolExpression
+{
+public:
+
+  // create a leaf node expression
+  nsMsgSearchBoolExpression(nsIMsgSearchTerm * aNewTerm,
+                              char * aEncodingString = NULL);
+
+  // create a non-leaf node expression containing 2 expressions
+    // and a boolean operator
+  nsMsgSearchBoolExpression(nsMsgSearchBoolExpression *,
+                              nsMsgSearchBoolExpression *,
+                              nsMsgSearchBooleanOperator boolOp);
+
+  nsMsgSearchBoolExpression();
+  ~nsMsgSearchBoolExpression();  // recursively destroys all sub
+                                   // expressions as well
+
+  // accessors
+
+    // Offline
+  static nsMsgSearchBoolExpression * AddSearchTerm (nsMsgSearchBoolExpression * aOrigExpr, nsIMsgSearchTerm * aNewTerm, char * aEncodingStr); // IMAP/NNTP
+    static nsMsgSearchBoolExpression * AddExpressionTree(nsMsgSearchBoolExpression * aOrigExpr, nsMsgSearchBoolExpression * aExpression, bool aBoolOp);
+
+    // parses the expression tree and all
+    // expressions underneath this node to
+    // determine if the end result is true or false.
+  bool OfflineEvaluate(nsIMsgDBHdr *msgToMatch,
+          const char *defaultCharset, nsIMsgSearchScopeTerm *scope,
+          nsIMsgDatabase *db, const char *headers, uint32_t headerSize,
+          bool Filtering);
+
+    // assuming the expression is for online
+    // searches, determine the length of the
+    // resulting IMAP/NNTP encoding string
+  int32_t CalcEncodeStrSize();
+
+    // fills pre-allocated
+    // memory in buffer with
+    // the IMAP/NNTP encoding for the expression
+  void GenerateEncodeStr(nsCString * buffer);
+
+  // if we are not a leaf node, then we have two other expressions
+    // and a boolean operator
+  nsMsgSearchBoolExpression * m_leftChild;
+  nsMsgSearchBoolExpression * m_rightChild;
+  nsMsgSearchBooleanOperator m_boolOp;
+
+protected:
+  // if we are a leaf node, all we have is a search term
+
+    nsIMsgSearchTerm * m_term;
+
+    // store IMAP/NNTP encoding for the search term if applicable
+  nsCString m_encodingStr;
+
+  // internal methods
+
+  // the idea is to separate the public interface for adding terms to
+    // the expression tree from the order of evaluation which influences
+    // how we internally construct the tree. Right now, we are supporting
+    // left to right evaluation so the tree is constructed to represent
+    // that by calling leftToRightAddTerm. If future forms of evaluation
+    // need to be supported, add new methods here for proper tree construction.
+  nsMsgSearchBoolExpression * leftToRightAddTerm(nsIMsgSearchTerm * newTerm,
+                                                   char * encodingStr);
+};
+
+#endif