[qt] Display more helpful message when adding a send address has failed

Addresses #12796.

When we're unable to add a sending address to the address book because it
already exists as a receiving address, display a message indicating as much.
This should help avoid confusion about an address supposedly already in the
book but which isn't currently visible in the interface.

1 files changed, 7 insertions, 2 deletions

diff --git a/src/qt/addresstablemodel.h b/src/qt/addresstablemodel.h
index d7aeda9d8e..979f861fea 100644
--- a/src/qt/addresstablemodel.h
+++ b/src/qt/addresstablemodel.h
@@ -67,10 +67,12 @@ public:
      */
     QString addRow(const QString &type, const QString &label, const QString &address, const OutputType address_type);
 
-    /* Look up label for address in address book, if not found return empty string.
-     */
+    /** Look up label for address in address book, if not found return empty string. */
     QString labelForAddress(const QString &address) const;
 
+    /** Look up purpose for address in address book, if not found return empty string. */
+    QString purposeForAddress(const QString &address) const;
+
     /* Look up row index of an address in the model.
        Return -1 if not found.
      */
@@ -86,6 +88,9 @@ private:
     QStringList columns;
     EditStatus editStatus;
 
+    /** Look up address book data given an address string. */
+    bool getAddressData(const QString &address, std::string* name, std::string* purpose) const;
+
     /** Notify listeners that data changed. */
     void emitDataChanged(int index);