# HG changeset patch
# User Chris Cannam
# Date 1242316036 0
# Node ID 063da8955f65d476399187c5b02e29bc28e0596e
# Parent  a03aafaacb5abcd0ac7b62a1a00855778c9f0b6e
* Try to avoid URI clashes with existing URIs in the file, when writing
  with --rdf-append

diff -r a03aafaacb5a -r 063da8955f65 rdf/RDFFeatureWriter.cpp
--- a/rdf/RDFFeatureWriter.cpp	Thu May 14 14:33:40 2009 +0000
+++ b/rdf/RDFFeatureWriter.cpp	Thu May 14 15:47:16 2009 +0000
@@ -219,6 +219,40 @@
 }
 
 void
+RDFFeatureWriter::reviewFileForAppending(QString filename)
+{
+    // Appending to an RDF file is tricky, because we need to ensure
+    // that our URIs differ from any already in the file.  This is a
+    // dirty grubby low-rent way of doing that.  This function is
+    // called by FileFeatureWriter::getOutputFile when in append mode.
+
+    std::cerr << "reviewFileForAppending(" << filename.toStdString() << ")" << std::endl;
+
+    QFile file(filename);
+
+    // just return, don't report failure -- function that called us will do that
+    if (!file.open(QIODevice::ReadOnly)) return;
+
+    QTextStream in(&file);
+
+    QRegExp localObjectUriWithDigits(":[^ ]+_([0-9]+) a ");
+
+    while (!in.atEnd()) {
+        QString line = in.readLine();
+        if (line.length() > 120) { // probably data
+            continue;
+        }
+        if (localObjectUriWithDigits.indexIn(line) > -1) {
+            QString numeric = localObjectUriWithDigits.cap(1);
+            int number = numeric.toInt();
+            if (number >= m_count) m_count = number + 1;
+        }
+    }
+
+    file.close();
+}
+
+void
 RDFFeatureWriter::writeSignalDescription(QTextStream *sptr,
                                          QString trackId)
 {
@@ -244,8 +278,7 @@
         }
     }
 
-    //!!! FIX: If we are appending, we need to start counting after
-    //all of the existing counts that are already in the file!
+    // Note reviewFileForAppending above (when opening in append mode)
 
     uint64_t signalCount = m_count++;
 
diff -r a03aafaacb5a -r 063da8955f65 rdf/RDFFeatureWriter.h
--- a/rdf/RDFFeatureWriter.h	Thu May 14 14:33:40 2009 +0000
+++ b/rdf/RDFFeatureWriter.h	Thu May 14 15:47:16 2009 +0000
@@ -68,6 +68,8 @@
 
     QString m_fixedEventTypeURI;
 
+    virtual void reviewFileForAppending(QString filename);
+
     void writePrefixes(QTextStream *);
     void writeSignalDescription(QTextStream *, QString);
     void writeLocalFeatureTypes(QTextStream *,