feat: complete contacts in the query bar

from: and to: now offer the vCard store's addresses, each quoted via
SearchTerm::quote() with the contact's name as the description. The store
is the enumerator libnotmuch does not expose, which is what the old
complete-nothing comment said was missing; it keeps that role for folder:,
subject:, attachment:, thread: and id:.

With no store configured the branch returns {} and the behaviour is
unchanged.

2 files changed, 34 insertions, 4 deletions

diff --git a/src/querycompleter.cpp b/src/querycompleter.cpp
index 9848faf..1b4c2fc 100644
--- a/src/querycompleter.cpp
+++ b/src/querycompleter.cpp
@@ -19,6 +19,7 @@
 #include "querycompleter.h"
 
 #include "config.h"
+#include "searchterm.h"
 
 #include <QCompleter>
 #include <QCoreApplication>
@@ -597,6 +598,11 @@ void QueryCompleter::setTags(const QStringList &tags)
     m_tags = tags;
 }
 
+void QueryCompleter::setContacts(const QList<Contact> &contacts)
+{
+    m_contacts = contacts;
+}
+
 QList<CompletionEntry> QueryCompleter::entriesFor(
     const CompletionContext &context) const
 {
@@ -649,10 +655,27 @@ QList<CompletionEntry> QueryCompleter::entriesFor(
         return entries;
     }
 
-    // from:, to:, folder:, subject:, attachment:, thread:, id: complete no
-    // values. Addresses need an enumerator libnotmuch does not expose;
-    // folder: matches a Maildir folder name that config cannot enumerate, and
-    // the rest are free text.
+    // The addresses live in the vCard store, which is the enumerator
+    // libnotmuch does not expose. The VALUE is the bare address because that
+    // is what notmuch matches on; the contact's name is the description, so
+    // the popup says who owns it.
+    if (context.prefix == QStringLiteral("from")
+        || context.prefix == QStringLiteral("to")) {
+        QList<CompletionEntry> entries;
+        entries.reserve(m_contacts.size());
+        for (const Contact &contact : m_contacts) {
+            const QString address = SearchTerm::quote(contact.email);
+            if (address.isEmpty())
+                continue;
+            entries.append({ address, contact.name });
+        }
+        return entries;
+    }
+
+    // folder:, subject:, attachment:, thread:, id: complete no values. folder:
+    // matches a Maildir folder name that config cannot enumerate, and the rest
+    // are free text. from: and to: no longer belong in this list: the vCards
+    // are the enumerator they lacked.
     return {};
 }
 
diff --git a/src/querycompleter.h b/src/querycompleter.h
index 27161bc..147909c 100644
--- a/src/querycompleter.h
+++ b/src/querycompleter.h
@@ -24,6 +24,7 @@
 #include <QStringList>
 
 #include "completionentry.h"
+#include "contactstore.h"
 
 class Config;
 class QCompleter;
@@ -98,6 +99,11 @@ public:
     /// Replaces the tag candidates. Called with the worker's allTagsReady.
     void setTags(const QStringList &tags);
 
+    /// Replaces the address candidates. Called by MainWindow after the vCard
+    /// store is read, and REPLACES rather than merges for the same reason
+    /// setTags does: the caller owns the list.
+    void setContacts(const QList<Contact> &contacts);
+
     /// The candidate values for a context, in the order they are offered.
     QStringList candidatesFor(const CompletionContext &context) const;
 
@@ -134,6 +140,7 @@ private:
     QLineEdit *m_edit = nullptr;
     const Config &m_config;
     QStringList m_tags;
+    QList<Contact> m_contacts;
 
     /// Set while the filter is redelivering a key to the popup. The filter is
     /// installed on the application and sendEvent re-runs application filters,