8 files changed, 185 insertions, 56 deletions

diff --git a/desktop-widgets/command.cpp b/desktop-widgets/command.cpp
index a901d9e48..0f08d0637 100644
--- a/desktop-widgets/command.cpp
+++ b/desktop-widgets/command.cpp
@@ -175,4 +175,9 @@ void editDiveSiteNew(const QVector<dive *> dives, const QString &newName, struct
 	execute(new EditDiveSiteNew(dives, newName, oldValue));
 }
 
+void editTags(const QVector<dive *> &dives, const QStringList &newList, struct dive *d)
+{
+	execute(new EditTags(dives, newList, d));
+}
+
 } // namespace Command
diff --git a/desktop-widgets/command.h b/desktop-widgets/command.h
index 9d18f09ae..e94023c81 100644
--- a/desktop-widgets/command.h
+++ b/desktop-widgets/command.h
@@ -61,6 +61,7 @@ void editAirTemp(const QVector<dive *> dives, int newValue, int oldValue);
 void editWaterTemp(const QVector<dive *> dives, int newValue, int oldValue);
 void editDiveSite(const QVector<dive *> dives, struct dive_site *newValue, struct dive_site *oldValue);
 void editDiveSiteNew(const QVector<dive *> dives, const QString &newName, struct dive_site *oldValue);
+void editTags(const QVector<dive *> &dives, const QStringList &newList, struct dive *d);
 
 } // namespace Command
 
diff --git a/desktop-widgets/command_edit.cpp b/desktop-widgets/command_edit.cpp
index c1e00bdf1..c3a47016e 100644
--- a/desktop-widgets/command_edit.cpp
+++ b/desktop-widgets/command_edit.cpp
@@ -325,4 +325,129 @@ DiveField EditMode::fieldId() const
 	return DiveField::MODE;
 }
 
+// ***** Tag based commands *****
+EditTagsBase::EditTagsBase(const QVector<dive *> &divesIn, const QStringList &newListIn, struct dive *d):
+	dives(divesIn.toStdVector()),
+	newList(newListIn),
+	oldDive(d)
+{
+}
+
+// Two helper functions: returns true if first list contains any tag or
+// misses any tag of second list.
+static bool containsAny(const QStringList &tags1, const QStringList &tags2)
+{
+	return std::any_of(tags2.begin(), tags2.end(), [&tags1](const QString &tag)
+			   { return tags1.contains(tag); });
+}
+
+static bool missesAny(const QStringList &tags1, const QStringList &tags2)
+{
+	return std::any_of(tags2.begin(), tags2.end(), [&tags1](const QString &tag)
+			   { return !tags1.contains(tag); });
+}
+
+// This is quite hackish: we can't use virtual functions in the constructor and
+// therefore can't initialize the list of dives [the values of the dives are
+// accessed by virtual functions]. Therefore, we (mis)use the fact that workToBeDone()
+// is called exactly once before adding the Command to the system and perform this here.
+// To be more explicit about this, we might think about renaming workToBeDone() to init().
+bool EditTagsBase::workToBeDone()
+{
+	// changing the tags on multiple dives is semantically strange - what's the right thing to do?
+	// here's what I think... add the tags that were added to the displayed dive and remove the tags
+	// that were removed from it
+
+	// Calculate tags to add and tags to remove
+	QStringList oldList = data(oldDive);
+	for (const QString &s: newList) {
+		if (!oldList.contains(s))
+			tagsToAdd.push_back(s);
+	}
+	for (const QString &s: oldList) {
+		if (!newList.contains(s))
+			tagsToRemove.push_back(s);
+	}
+
+	// Now search for all dives that either
+	//	- miss a tag to be added
+	//	- have a tag to be removed
+	std::vector<dive *> divesNew;
+	divesNew.reserve(dives.size());
+	for (dive *d: dives) {
+		QStringList tags = data(d);
+		if (missesAny(tags, tagsToAdd) || containsAny(tags, tagsToRemove))
+			divesNew.push_back(d);
+	}
+	dives = std::move(divesNew);
+
+	// Create a text for the menu entry. In the case of multiple dives add the number
+	size_t num_dives = dives.size();
+	if (num_dives > 0)
+		//: remove the part in parantheses for %n = 1
+		setText(tr("Edit %1 (%n dive(s))", "", num_dives).arg(fieldName()));
+
+	return num_dives;
+}
+
+void EditTagsBase::undo()
+{
+	if (dives.empty()) {
+		qWarning("Edit command called with empty dives list (shouldn't happen)");
+		return;
+	}
+
+	for (dive *d: dives) {
+		QStringList tags = data(d);
+		for (const QString &tag: tagsToRemove)
+			tags.removeAll(tag);
+		for (const QString &tag: tagsToAdd) {
+			if (!tags.contains(tag))
+				tags.push_back(tag);
+		}
+		invalidate_dive_cache(d); // Ensure that dive is written in git_save()
+		set(d, tags);
+	}
+
+	std::swap(tagsToAdd, tagsToRemove);
+
+	emit diveListNotifier.divesEdited(QVector<dive *>::fromStdVector(dives), fieldId());
+
+	mark_divelist_changed(true);
+}
+
+// Undo and redo do the same as just the stored value is exchanged
+void EditTagsBase::redo()
+{
+	undo();
+}
+
+// ***** Tags *****
+QStringList EditTags::data(struct dive *d) const
+{
+	QStringList res;
+	for (const struct tag_entry *tag = d->tag_list; tag; tag = tag->next)
+		res.push_back(tag->tag->name);
+	return res;
+}
+
+void EditTags::set(struct dive *d, const QStringList &v) const
+{
+	taglist_free(d->tag_list);
+	d->tag_list = NULL;
+	for (const QString &tag: v)
+		taglist_add_tag(&d->tag_list, qPrintable(tag));
+	taglist_cleanup(&d->tag_list);
+}
+
+QString EditTags::fieldName() const
+{
+	return tr("tags");
+}
+
+DiveField EditTags::fieldId() const
+{
+	return DiveField::TAGS;
+}
+
 } // namespace Command
diff --git a/desktop-widgets/command_edit.h b/desktop-widgets/command_edit.h
index 4eb1da848..fab951799 100644
--- a/desktop-widgets/command_edit.h
+++ b/desktop-widgets/command_edit.h
@@ -136,6 +136,43 @@ public:
 	DiveField fieldId() const override;
 };
 
+// Fields that work with tag-lists (tags, buddies, divemasters) work differently and therefore
+// have their own base class. In this case, it's not a template, as all these lists are base
+// on strings.
+class EditTagsBase : public Base {
+	bool workToBeDone() override;
+
+	// Dives to be edited. For historical reasons, the *last* entry was
+	// the active dive when the user initialized the action. This dive
+	// will be made the current dive on redo / undo.
+	std::vector<dive *> dives;
+	QStringList newList;	// Temporary until initialized
+	struct dive *oldDive;	// Temporary until initialized
+public:
+	EditTagsBase(const QVector<dive *> &dives, const QStringList &newList, struct dive *d);
+
+protected:
+	QStringList tagsToAdd;
+	QStringList tagsToRemove;
+	void undo() override;
+	void redo() override;
+
+	// Getters, setters and parsers to be overriden by sub-classes.
+	virtual QStringList data(struct dive *d) const = 0;
+	virtual void set(struct dive *d, const QStringList &v) const = 0;
+	virtual QString fieldName() const = 0;	// Name of the field, used to create the undo menu-entry
+	virtual DiveField fieldId() const = 0;
+};
+
+class EditTags : public EditTagsBase {
+public:
+	using EditTagsBase::EditTagsBase;	// Use constructor of base class.
+	QStringList data(struct dive *d) const override;
+	void set(struct dive *d, const QStringList &v) const override;
+	QString fieldName() const override;
+	DiveField fieldId() const override;
+};
+
 } // namespace Command
 
 #endif
diff --git a/desktop-widgets/tab-widgets/maintab.cpp b/desktop-widgets/tab-widgets/maintab.cpp
index 11ec9690b..19fa56332 100644
--- a/desktop-widgets/tab-widgets/maintab.cpp
+++ b/desktop-widgets/tab-widgets/maintab.cpp
@@ -372,6 +372,9 @@ void MainTab::divesEdited(const QVector<dive *> &, DiveField field)
 		updateDiveSite(current_dive);
 		emit diveSiteChanged();
 		break;
+	case DiveField::TAGS:
+		ui.tagWidget->setText(get_taglist_string(current_dive->tag_list));
+		break;
 	default:
 		break;
 	}
@@ -788,7 +791,6 @@ void MainTab::acceptChanges()
 		// three text fields are somewhat special and are represented as tags
 		// in the UI - they need somewhat smarter handling
 		saveTaggedStrings(selectedDives);
-		saveTags(selectedDives);
 
 		if (cylindersModel->changed) {
 			mark_divelist_changed(true);
@@ -1108,57 +1110,11 @@ void MainTab::copyTagsToDisplayedDive()
 {
 	taglist_free(displayed_dive.tag_list);
 	displayed_dive.tag_list = NULL;
-	Q_FOREACH (const QString& tag, ui.tagWidget->getBlockStringList())
+	Q_FOREACH (const QString &tag, ui.tagWidget->getBlockStringList())
 		taglist_add_tag(&displayed_dive.tag_list, qPrintable(tag));
 	taglist_cleanup(&displayed_dive.tag_list);
 }
 
-// changing the tags on multiple dives is semantically strange - what's the right thing to do?
-// here's what I think... add the tags that were added to the displayed dive and remove the tags
-// that were removed from it
-void MainTab::saveTags(const QVector<dive *> &selectedDives)
-{
-	struct dive *cd = current_dive;
-	struct tag_entry *added_list = NULL;
-	struct tag_entry *removed_list = NULL;
-	struct tag_entry *tl;
-
-	copyTagsToDisplayedDive();
-
-	// figure out which tags were added and which tags were removed
-	added_list = taglist_added(cd ? cd->tag_list : NULL, displayed_dive.tag_list);
-	removed_list = taglist_added(displayed_dive.tag_list, cd ? cd->tag_list : NULL);
-
-	// dump_taglist("added tags:", added_list);
-	// dump_taglist("removed tags:", removed_list);
-
-	// we need to check if the tags were changed before just overwriting them
-	if (added_list == NULL && removed_list == NULL)
-		return;
-
-	MODIFY_DIVES(selectedDives,
-		// create a new tag list and all the existing tags that were not
-		// removed and then all the added tags
-		struct tag_entry *new_tag_list;
-		new_tag_list = NULL;
-		tl = mydive->tag_list;
-		while (tl) {
-			if (!taglist_contains(removed_list, tl->tag->name))
-				taglist_add_tag(&new_tag_list, tl->tag->name);
-			tl = tl->next;
-		}
-		tl = added_list;
-		while (tl) {
-			taglist_add_tag(&new_tag_list, tl->tag->name);
-			tl = tl->next;
-		}
-		taglist_free(mydive->tag_list);
-		mydive->tag_list = new_tag_list;
-	);
-	taglist_free(added_list);
-	taglist_free(removed_list);
-}
-
 // buddy and divemaster are represented in the UI just like the tags, but the internal
 // representation is just a string (with commas as delimiters). So we need to do the same
 // thing we did for tags, just differently
@@ -1226,15 +1182,12 @@ int MainTab::diffTaggedStrings(QString currentString, QString displayedString, Q
 	return removedList.length() + addedList.length();
 }
 
-void MainTab::on_tagWidget_textChanged()
+void MainTab::on_tagWidget_editingFinished()
 {
-	if (editMode == IGNORE || acceptingEdit == true)
-		return;
-
-	if (get_taglist_string(displayed_dive.tag_list) == ui.tagWidget->toPlainText())
+	if (editMode == IGNORE || acceptingEdit == true || !current_dive)
 		return;
 
-	markChangedWidget(ui.tagWidget);
+	Command::editTags(getSelectedDivesCurrentLast(), ui.tagWidget->getBlockStringList(), current_dive);
 }
 
 void MainTab::on_location_diveSiteSelected()
diff --git a/desktop-widgets/tab-widgets/maintab.h b/desktop-widgets/tab-widgets/maintab.h
index 4bff215ce..3b9fa26d6 100644
--- a/desktop-widgets/tab-widgets/maintab.h
+++ b/desktop-widgets/tab-widgets/maintab.h
@@ -89,7 +89,7 @@ slots:
 	void on_timeEdit_timeChanged(const QTime & time);
 	void on_rating_valueChanged(int value);
 	void on_visibility_valueChanged(int value);
-	void on_tagWidget_textChanged();
+	void on_tagWidget_editingFinished();
 	void editCylinderWidget(const QModelIndex &index);
 	void editWeightWidget(const QModelIndex &index);
 	void addDiveStarted();
@@ -119,7 +119,6 @@ private:
 	int lastTabSelectedDiveTrip;
 	void resetPallete();
 	void copyTagsToDisplayedDive();
-	void saveTags(const QVector<dive *> &selectedDives);
 	void saveTaggedStrings(const QVector<dive *> &selectedDives);
 	int diffTaggedStrings(QString currentString, QString displayedString, QStringList &addedList, QStringList &removedList);
 	void markChangedWidget(QWidget *w);
diff --git a/desktop-widgets/tagwidget.cpp b/desktop-widgets/tagwidget.cpp
index 6673b23ac..b09507537 100644
--- a/desktop-widgets/tagwidget.cpp
+++ b/desktop-widgets/tagwidget.cpp
@@ -211,3 +211,11 @@ void TagWidget::fixPopupPosition(int delta)
 		m_completer->popup()->setGeometry(toGlobal.x(), toGlobal.y() + delta +10, toGlobal.width(), toGlobal.height());
 	}
 }
+
+// Since we capture enter / return / tab, we never send an editingFinished() signal.
+// Therefore, override the focusOutEvent()
+void TagWidget::focusOutEvent(QFocusEvent *ev)
+{
+	GroupedLineEdit::focusOutEvent(ev);
+	emit editingFinished();
+}
diff --git a/desktop-widgets/tagwidget.h b/desktop-widgets/tagwidget.h
index f88b8a208..510b3c48b 100644
--- a/desktop-widgets/tagwidget.h
+++ b/desktop-widgets/tagwidget.h
@@ -28,6 +28,7 @@ slots:
 protected:
 	void keyPressEvent(QKeyEvent *e);
 private:
+	void focusOutEvent(QFocusEvent *ev) override;
 	QCompleter *m_completer;
 	bool lastFinishedTag;
 };