1 files changed, 97 insertions, 0 deletions
diff --git a/src/dialogs/EntryMultiCompletion.vala b/src/dialogs/EntryMultiCompletion.vala
new file mode 100644
index 0000000..8700f21
--- /dev/null
+++ b/src/dialogs/EntryMultiCompletion.vala
@@ -0,0 +1,97 @@
+/* Copyright 2016 Software Freedom Conservancy Inc.
+ * Copyright 2017 Jens Georg <mail@jensge.org>
+ *
+ * This software is licensed under the GNU LGPL (version 2.1 or later).
+ * See the COPYING file in this distribution.
+ */
+
+// Entry completion for values separated by separators (e.g. comma in the case of tags)
+// Partly inspired by the class of the same name in gtkmm-utils by Marko Anastasov
+public class EntryMultiCompletion : Gtk.EntryCompletion {
+    private string delimiter;
+
+    public EntryMultiCompletion(Gee.Collection<string> completion_list, string? delimiter) {
+        assert(delimiter == null || delimiter.length == 1);
+        this.delimiter = delimiter;
+
+        set_model(create_completion_store(completion_list));
+        set_text_column(0);
+        set_match_func(match_func);
+    }
+
+    private static Gtk.ListStore create_completion_store(Gee.Collection<string> completion_list) {
+        Gtk.ListStore completion_store = new Gtk.ListStore(1, typeof(string));
+        Gtk.TreeIter store_iter;
+        Gee.Iterator<string> completion_iter = completion_list.iterator();
+        while (completion_iter.next()) {
+            completion_store.append(out store_iter);
+            completion_store.set(store_iter, 0, completion_iter.get(), -1);
+        }
+
+        return completion_store;
+    }
+
+    private bool match_func(Gtk.EntryCompletion completion, string key, Gtk.TreeIter iter) {
+        Gtk.TreeModel model = completion.get_model();
+        string possible_match;
+        model.get(iter, 0, out possible_match);
+
+        // Normalize key and possible matches to allow comparison of non-ASCII characters.
+        // Use a "COMPOSE" normalization to allow comparison to the position value returned by
+        // Gtk.Entry, i.e. one character=one position. Using the default normalization a character
+        // like "é" or "ö" would have a length of two.
+        possible_match = possible_match.casefold().normalize(-1, NormalizeMode.ALL_COMPOSE);
+        string normed_key = key.normalize(-1, NormalizeMode.ALL_COMPOSE);
+
+        if (delimiter == null) {
+            return possible_match.has_prefix(normed_key.strip());
+        } else {
+            if (normed_key.contains(delimiter)) {
+                // check whether cursor is before last delimiter
+                int offset = normed_key.char_count(normed_key.last_index_of_char(delimiter[0]));
+                int position = ((Gtk.Entry) get_entry()).get_position();
+                if (position <= offset)
+                    return false; // TODO: Autocompletion for tags not last in list
+            }
+
+            string last_part = get_last_part(normed_key.strip(), delimiter);
+
+            if (last_part.length == 0)
+                return false; // need at least one character to show matches
+
+            return possible_match.has_prefix(last_part.strip());
+        }
+    }
+
+    public override bool match_selected(Gtk.TreeModel model, Gtk.TreeIter iter) {
+        string match;
+        model.get(iter, 0, out match);
+
+        Gtk.Entry entry = (Gtk.Entry)get_entry();
+
+        string old_text = entry.get_text().normalize(-1, NormalizeMode.ALL_COMPOSE);
+        if (old_text.length > 0) {
+            if (old_text.contains(delimiter)) {
+                old_text = old_text.substring(0, old_text.last_index_of_char(delimiter[0]) + 1) + (delimiter != " " ? " " : "");
+            } else
+                old_text = "";
+        }
+
+        string new_text = old_text + match + delimiter + (delimiter != " " ? " " : "");
+        entry.set_text(new_text);
+        entry.set_position((int) new_text.length);
+
+        return true;
+    }
+
+    // Find last string after any delimiter
+    private static string get_last_part(string s, string delimiter) {
+        string[] split = s.split(delimiter);
+
+        if((split != null) && (split[0] != null)) {
+            return split[split.length - 1];
+        } else {
+            return "";
+        }
+    }
+}