1 files changed, 433 insertions, 0 deletions
diff --git a/src/object/sp-page.cpp b/src/object/sp-page.cpp
new file mode 100644
index 0000000..7107c10
--- /dev/null
+++ b/src/object/sp-page.cpp
@@ -0,0 +1,433 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape pages implementation
+ *
+ * Authors:
+ *   Martin Owens <doctormo@geek-2.com>
+ *
+ * Copyright (C) 2021 Martin Owens
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <glibmm/i18n.h>
+
+#include "sp-page.h"
+
+#include "attributes.h"
+#include "desktop.h"
+#include "display/control/canvas-page.h"
+#include "inkscape.h"
+#include "object/object-set.h"
+#include "sp-namedview.h"
+#include "sp-root.h"
+
+using Inkscape::DocumentUndo;
+
+SPPage::SPPage()
+    : SPObject()
+{
+    _canvas_item = new Inkscape::CanvasPage();
+}
+
+SPPage::~SPPage()
+{
+    delete _canvas_item;
+    _canvas_item = nullptr;
+}
+
+void SPPage::build(SPDocument *document, Inkscape::XML::Node *repr)
+{
+    SPObject::build(document, repr);
+
+    this->readAttr(SPAttr::INKSCAPE_LABEL);
+    this->readAttr(SPAttr::X);
+    this->readAttr(SPAttr::Y);
+    this->readAttr(SPAttr::WIDTH);
+    this->readAttr(SPAttr::HEIGHT);
+
+    /* Register */
+    document->addResource("page", this);
+}
+
+void SPPage::release()
+{
+    if (this->document) {
+        // Unregister ourselves
+        this->document->removeResource("page", this);
+    }
+
+    SPObject::release();
+}
+
+void SPPage::set(SPAttr key, const gchar *value)
+{
+    switch (key) {
+        case SPAttr::X:
+            this->x.readOrUnset(value);
+            break;
+        case SPAttr::Y:
+            this->y.readOrUnset(value);
+            break;
+        case SPAttr::WIDTH:
+            this->width.readOrUnset(value);
+            break;
+        case SPAttr::HEIGHT:
+            this->height.readOrUnset(value);
+            break;
+        default:
+            SPObject::set(key, value);
+            break;
+    }
+    this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+}
+
+/**
+ * Gets the rectangle in document units
+ */
+Geom::Rect SPPage::getRect() const
+{
+    return Geom::Rect(this->x.computed, this->y.computed, this->x.computed + this->width.computed,
+                      this->y.computed + this->height.computed);
+}
+
+/**
+ * Get the rectangle of the page, in desktop units
+ */
+Geom::Rect SPPage::getDesktopRect() const
+{
+    auto rect = getDocumentRect();
+    rect *= document->dt2doc();
+    return rect;
+}
+
+/**
+ * Get the rectangle of the page, scaled to the document.
+ */
+Geom::Rect SPPage::getDocumentRect() const
+{
+    return getRect() * document->getDocumentScale();
+}
+
+/**
+ * Like getDesktopRect but returns a slightly shrunken rectangle
+ * so interactions don't confuse the border with the object.
+ */
+Geom::Rect SPPage::getSensitiveRect() const
+{
+    auto rect = getDesktopRect();
+    rect.expandBy(-0.1);
+    return rect;
+}
+
+/**
+ * Set the page rectangle in it's native units.
+ */
+void SPPage::setRect(Geom::Rect rect)
+{
+    this->x = rect.left();
+    this->y = rect.top();
+    this->width = rect.width();
+    this->height = rect.height();
+
+    // This is needed to update the xml
+    this->updateRepr();
+
+    // This eventually calls the ::update below while idle
+    this->requestModified(SP_OBJECT_MODIFIED_FLAG);
+}
+
+/**
+ * Set the page rectangle is desktop coordinates.
+ */
+void SPPage::setDesktopRect(Geom::Rect rect)
+{
+    rect *= document->doc2dt();
+    setRect(rect * document->getDocumentScale().inverse());
+}
+
+/**
+ * Set just the height and width from a predefined size.
+ */
+void SPPage::setDesktopSize(double width, double height)
+{
+    auto rect = getDesktopRect();
+    rect.setMax(rect.corner(0) + Geom::Point(width, height));
+    setDesktopRect(rect);
+}
+
+/**
+ * Get the items which are ONLY on this page and don't overlap.
+ *
+ * This ignores layers so items in the same layer which are shared
+ * between pages are not moved around or exported into pages they
+ * shouldn't be.
+ *
+ * @param hidden - Return hidden items (default: true)
+ */
+std::vector<SPItem *> SPPage::getExclusiveItems(bool hidden) const
+{
+    return document->getItemsInBox(0, getDocumentRect(), hidden, true, true, false);
+}
+
+/**
+ * Like ExcludiveItems above but get all the items which are inside or overlapping.
+ *
+ * @param hidden - Return hidden items (default: true)
+ */
+std::vector<SPItem *> SPPage::getOverlappingItems(bool hidden) const
+{
+    return document->getItemsPartiallyInBox(0, getDocumentRect(), hidden, true, true, false);
+}
+
+/**
+ * Return true if this item is contained within the page boundary.
+ */
+bool SPPage::itemOnPage(SPItem *item, bool contains) const
+{
+    if (auto box = item->desktopGeometricBounds()) {
+        if (contains) {
+            return getDesktopRect().contains(*box);
+        }
+        return getDesktopRect().intersects(*box);
+    }
+    return false;
+}
+
+/**
+ * Returns true if this page is the same as the viewport.
+ */
+bool SPPage::isViewportPage() const
+{
+    auto rect = document->preferredBounds();
+    return getDesktopRect().corner(0) == rect->corner(0);
+}
+
+/**
+ * Shows the page in the given canvas item group.
+ */
+void SPPage::showPage(Inkscape::CanvasItemGroup *fg, Inkscape::CanvasItemGroup *bg)
+{
+    _canvas_item->add(getDesktopRect(), fg, bg);
+    // The final steps are completed in an update cycle
+    this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+}
+
+/**
+ * Sets the default attributes from the namedview.
+ */
+bool SPPage::setDefaultAttributes()
+{
+    if (document->getPageManager().setDefaultAttributes(_canvas_item)) {
+        this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+        return true;
+    }
+    return false;
+}
+
+/**
+ * Set the selected high-light for this page.
+ */
+void SPPage::setSelected(bool sel)
+{
+    this->_canvas_item->is_selected = sel;
+    this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+}
+
+/**
+ * Returns the page number (order of pages) starting at 1
+ */
+int SPPage::getPageIndex() const
+{
+    return document->getPageManager().getPageIndex(this);
+}
+
+/**
+ * Set this page to a new order in the page stack.
+ *
+ * @param index - Placement of page in the stack, starting at '0'
+ * @param swap_page - Swap the rectangle position
+ *
+ * @returns true if page has been moved.
+ */
+bool SPPage::setPageIndex(int index, bool swap_page)
+{
+    int current = getPageIndex();
+
+    if (current != index) {
+        auto &page_manager = document->getPageManager();
+
+        // The page we're going to be shifting to
+        auto sibling = page_manager.getPage(index);
+
+        // Insertions are done to the right of the sibling
+        if (index < current) {
+            index -= 1;
+        }
+        auto insert_after = page_manager.getPage(index);
+
+        // We may have selected an index off the end, so attach it after the last page.
+        if (!insert_after && index > 0) {
+            insert_after = page_manager.getLastPage();
+            sibling = nullptr; // disable swap
+        }
+
+        if (insert_after) {
+            if (this == insert_after) {
+                g_warning("Page is already at this index. Not moving.");
+                return false;
+            }
+            // Attach after the given page
+            getRepr()->parent()->changeOrder(getRepr(), insert_after->getRepr());
+        } else {
+            // Attach to before any existing page
+            sibling = page_manager.getFirstPage();
+            getRepr()->parent()->changeOrder(getRepr(), nullptr);
+        }
+        if (sibling && swap_page) {
+            swapPage(sibling, true);
+        }
+        return true;
+    }
+    return false;
+}
+
+/**
+ * Returns the sibling page next to this one in the stack order.
+ */
+SPPage *SPPage::getNextPage()
+{
+    SPObject *item = this;
+    while ((item = item->getNext())) {
+        if (auto next = dynamic_cast<SPPage *>(item)) {
+            return next;
+        }
+    }
+    return nullptr;
+}
+
+/**
+ * Returns the sibling page previous to this one in the stack order.
+ */
+SPPage *SPPage::getPreviousPage()
+{
+    SPObject *item = this;
+    while ((item = item->getPrev())) {
+        if (auto prev = dynamic_cast<SPPage *>(item)) {
+            return prev;
+        }
+    }
+    return nullptr;
+}
+
+/**
+ * Move the page by the given affine, in desktop units.
+ *
+ * @param translate - The positional translation to apply.
+ * @param with_objects - Flag to request that connected objects also move.
+ */
+void SPPage::movePage(Geom::Affine translate, bool with_objects)
+{
+    if (translate.isTranslation()) {
+        if (with_objects) {
+            // Move each item that is overlapping this page too
+            moveItems(translate * document->dt2doc(), getOverlappingItems());
+        }
+        setDesktopRect(getDesktopRect() * translate);
+    }
+}
+
+/**
+ * Move the given items by the given translation in document units.
+ *
+ * @param translate - The movement to be applied
+ * @param objects - a vector of SPItems to move
+ */
+void SPPage::moveItems(Geom::Affine translate, std::vector<SPItem *> const &objects)
+{
+    for (auto &item : objects) {
+        if (item->isLocked()) {
+            continue;
+        }
+        if (auto parent_item = dynamic_cast<SPItem *>(item->parent)) {
+            auto move = item->i2dt_affine() * (translate * parent_item->i2doc_affine().inverse());
+            item->doWriteTransform(move, &move, false);
+        }
+    }
+}
+
+/**
+ * Swap the locations of this page with another page (see movePage)
+ *
+ * @param other - The other page to swap with
+ * @param with_objects - Should the page objects move too.
+ */
+void SPPage::swapPage(SPPage *other, bool with_objects)
+{
+    // Swapping with the viewport page must be handled gracefully.
+    if (this->isViewportPage()) {
+        auto other_rect = other->getDesktopRect();
+        auto new_rect = Geom::Rect(Geom::Point(0, 0),
+            Geom::Point(other_rect.width(), other_rect.height()));
+        this->document->fitToRect(new_rect, false);
+    } else if (other->isViewportPage()) {
+        other->swapPage(this, with_objects);
+        return;
+    }
+
+    auto this_affine = Geom::Translate(getDesktopRect().corner(0));
+    auto other_affine = Geom::Translate(other->getDesktopRect().corner(0));
+    movePage(this_affine.inverse() * other_affine, with_objects);
+    other->movePage(other_affine.inverse() * this_affine, with_objects);
+}
+
+void SPPage::update(SPCtx * /*ctx*/, unsigned int /*flags*/)
+{
+    // This is manual because this is not an SPItem, but it's own visual identity.
+    _canvas_item->update(getDesktopRect(), this->label());
+}
+
+/**
+ * Write out the page's data into it's xml structure.
+ */
+Inkscape::XML::Node *SPPage::write(Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags)
+{
+    if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
+        repr = xml_doc->createElement("inkscape:page");
+    }
+
+    repr->setAttributeSvgDouble("x", this->x.computed);
+    repr->setAttributeSvgDouble("y", this->y.computed);
+    repr->setAttributeSvgDouble("width", this->width.computed);
+    repr->setAttributeSvgDouble("height", this->height.computed);
+
+    return SPObject::write(xml_doc, repr, flags);
+}
+
+std::string SPPage::getDefaultLabel() const
+{
+    gchar *format = g_strdup_printf(_("Page %d"), getPagePosition());
+    auto ret = std::string(format);
+    g_free(format);
+    return ret;
+}
+
+std::string SPPage::getLabel() const
+{
+    auto ret = label();
+    if (!ret) {
+        return getDefaultLabel();
+    }
+    return std::string(ret);
+}
+
+/*
+  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 :