1 files changed, 184 insertions, 0 deletions
diff --git a/src/object-hierarchy.cpp b/src/object-hierarchy.cpp
new file mode 100644
index 0000000..c05bb6f
--- /dev/null
+++ b/src/object-hierarchy.cpp
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Object hierarchy implementation.
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2004 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <cstdio>
+
+#include "object-hierarchy.h"
+
+#include "object/sp-object.h"
+
+namespace Inkscape {
+
+ObjectHierarchy::ObjectHierarchy(SPObject *top) {
+    if (top) {
+        _addBottom(top);
+    }
+}
+
+ObjectHierarchy::~ObjectHierarchy() {
+    _clear();
+}
+
+void ObjectHierarchy::clear() {
+    _clear();
+    _changed_signal.emit(nullptr, nullptr);
+}
+
+void ObjectHierarchy::setTop(SPObject *object) {
+    if (object == nullptr) { printf("Assertion object != NULL failed\n"); return; }
+
+    if ( top() == object ) {
+        return;
+    }
+
+    if (!top()) {
+        _addTop(object);
+    } else if (object->isAncestorOf(top())) {
+        _addTop(object, top());
+    } else if ( object == bottom() || object->isAncestorOf(bottom()) ) {
+        _trimAbove(object);
+    } else {
+        _clear();
+        _addTop(object);
+    }
+
+    _changed_signal.emit(top(), bottom());
+}
+
+void ObjectHierarchy::_addTop(SPObject *senior, SPObject *junior) {
+    assert(junior != NULL);
+    assert(senior != NULL);
+
+    SPObject *object = junior->parent;
+    do {
+        _addTop(object);
+        object = object->parent;
+    } while ( object != senior );
+}
+
+void ObjectHierarchy::_addTop(SPObject *object) {
+    assert(object != NULL);
+    _hierarchy.push_back(_attach(object));
+    _added_signal.emit(object);
+}
+
+void ObjectHierarchy::_trimAbove(SPObject *limit) {
+    while ( !_hierarchy.empty() && _hierarchy.back().object != limit ) {
+        SPObject *object=_hierarchy.back().object;
+
+        sp_object_ref(object, nullptr);
+        _detach(_hierarchy.back());
+        _hierarchy.pop_back();
+        _removed_signal.emit(object);
+        sp_object_unref(object, nullptr);
+    }
+}
+
+void ObjectHierarchy::setBottom(SPObject *object) {
+    if (object == nullptr) { printf("assertion object != NULL failed\n"); return; }
+
+    if ( bottom() == object ) {
+        return;
+    }
+
+    if (!top()) {
+        _addBottom(object);
+    } else if (bottom()->isAncestorOf(object)) {
+        _addBottom(bottom(), object);
+    } else if ( top() == object ) {
+        _trimBelow(top());
+    } else if (top()->isAncestorOf(object)) {
+        if (object->isAncestorOf(bottom())) {
+            _trimBelow(object);
+        } else { // object is a sibling or cousin of bottom()
+            SPObject *saved_top=top();
+            sp_object_ref(saved_top, nullptr);
+            _clear();
+            _addBottom(saved_top);
+            _addBottom(saved_top, object);
+            sp_object_unref(saved_top, nullptr);
+        }
+    } else {
+        _clear();
+        _addBottom(object);
+    }
+
+    _changed_signal.emit(top(), bottom());
+}
+
+void ObjectHierarchy::_trimBelow(SPObject *limit) {
+    while ( !_hierarchy.empty() && _hierarchy.front().object != limit ) {
+        SPObject *object=_hierarchy.front().object;
+        sp_object_ref(object, nullptr);
+        _detach(_hierarchy.front());
+        _hierarchy.pop_front();
+        _removed_signal.emit(object);
+        sp_object_unref(object, nullptr);
+    }
+}
+
+void ObjectHierarchy::_addBottom(SPObject *senior, SPObject *junior) {
+    assert(junior != NULL);
+    assert(senior != NULL);
+
+    if ( junior != senior ) {
+        _addBottom(senior, junior->parent);
+        _addBottom(junior);
+    }
+}
+
+void ObjectHierarchy::_addBottom(SPObject *object) {
+    assert(object != NULL);
+    _hierarchy.push_front(_attach(object));
+    _added_signal.emit(object);
+}
+
+void ObjectHierarchy::_trim_for_release(SPObject *object) {
+    this->_trimBelow(object);
+    assert(!this->_hierarchy.empty());
+    assert(this->_hierarchy.front().object == object);
+
+    sp_object_ref(object, nullptr);
+    this->_detach(this->_hierarchy.front());
+    this->_hierarchy.pop_front();
+    this->_removed_signal.emit(object);
+    sp_object_unref(object, nullptr);
+
+    this->_changed_signal.emit(this->top(), this->bottom());
+}
+
+ObjectHierarchy::Record ObjectHierarchy::_attach(SPObject *object) {
+    sp_object_ref(object, nullptr);
+    sigc::connection connection
+      = object->connectRelease(
+          sigc::mem_fun(*this, &ObjectHierarchy::_trim_for_release)
+        );
+    return Record(object, connection);
+}
+
+void ObjectHierarchy::_detach(ObjectHierarchy::Record &rec) {
+    rec.connection.disconnect();
+    sp_object_unref(rec.object, nullptr);
+}
+
+}
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :