SharpMuPDF/mupdf/source/xps/xps-link.c

// Copyright (C) 2004-2022 Artifex Software, Inc.
//
// This file is part of MuPDF.
//
// MuPDF is free software: you can redistribute it and/or modify it under the
// terms of the GNU Affero General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// MuPDF is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
// details.
//
// You should have received a copy of the GNU Affero General Public License
// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>
//
// Alternative licensing terms are available from the licensor.
// For commercial licensing, see <https://www.artifex.com/> or contact
// Artifex Software, Inc., 39 Mesa Street, Suite 108A, San Francisco,
// CA 94129, USA, for further information.

#include "mupdf/fitz.h"
#include "xps-imp.h"

#include <string.h>
#include <stdlib.h>

/* Quick parsing of document to find links. */

static void
xps_load_links_in_element(fz_context *ctx, xps_document *doc, fz_matrix ctm,
		char *base_uri, xps_resource *dict, fz_xml *node, fz_link **link);

static void
xps_add_link(fz_context *ctx, xps_document *doc, fz_rect area, char *base_uri, char *target_uri, fz_link **head)
{
	fz_link *link = fz_new_derived_link(ctx, fz_link, area, target_uri);
	link->next = *head;
	*head = link;
}

static void
xps_load_links_in_path(fz_context *ctx, xps_document *doc, fz_matrix ctm,
		char *base_uri, xps_resource *dict, fz_xml *root, fz_link **link)
{
	char *navigate_uri_att = fz_xml_att(root, "FixedPage.NavigateUri");
	if (navigate_uri_att)
	{
		char *transform_att = fz_xml_att(root, "RenderTransform");
		fz_xml *transform_tag = fz_xml_down(fz_xml_find_down(root, "Path.RenderTransform"));

		char *data_att = fz_xml_att(root, "Data");
		fz_xml *data_tag = fz_xml_down(fz_xml_find_down(root, "Path.Data"));

		fz_path *path = NULL;
		int fill_rule;
		fz_rect area;

		xps_resolve_resource_reference(ctx, doc, dict, &data_att, &data_tag, NULL);
		xps_resolve_resource_reference(ctx, doc, dict, &transform_att, &transform_tag, NULL);

		ctm = xps_parse_transform(ctx, doc, transform_att, transform_tag, ctm);

		if (data_att)
			path = xps_parse_abbreviated_geometry(ctx, doc, data_att, &fill_rule);
		else if (data_tag)
			path = xps_parse_path_geometry(ctx, doc, dict, data_tag, 0, &fill_rule);
		if (path)
		{
			fz_try(ctx)
				area = fz_bound_path(ctx, path, NULL, ctm);
			fz_always(ctx)
				fz_drop_path(ctx, path);
			fz_catch(ctx)
				fz_rethrow(ctx);
			xps_add_link(ctx, doc, area, base_uri, navigate_uri_att, link);
		}
	}
}

static void
xps_load_links_in_glyphs(fz_context *ctx, xps_document *doc, fz_matrix ctm,
		char *base_uri, xps_resource *dict, fz_xml *root, fz_link **link)
{
	char *navigate_uri_att = fz_xml_att(root, "FixedPage.NavigateUri");
	if (navigate_uri_att)
	{
		char *transform_att = fz_xml_att(root, "RenderTransform");
		fz_xml *transform_tag = fz_xml_down(fz_xml_find_down(root, "Path.RenderTransform"));

		char *bidi_level_att = fz_xml_att(root, "BidiLevel");
		char *font_size_att = fz_xml_att(root, "FontRenderingEmSize");
		char *font_uri_att = fz_xml_att(root, "FontUri");
		char *origin_x_att = fz_xml_att(root, "OriginX");
		char *origin_y_att = fz_xml_att(root, "OriginY");
		char *is_sideways_att = fz_xml_att(root, "IsSideways");
		char *indices_att = fz_xml_att(root, "Indices");
		char *unicode_att = fz_xml_att(root, "UnicodeString");
		char *style_att = fz_xml_att(root, "StyleSimulations");

		int is_sideways = 0;
		int bidi_level = 0;
		fz_font *font;
		fz_text *text = NULL;
		fz_rect area;

		xps_resolve_resource_reference(ctx, doc, dict, &transform_att, &transform_tag, NULL);

		ctm = xps_parse_transform(ctx, doc, transform_att, transform_tag, ctm);

		if (is_sideways_att)
			is_sideways = !strcmp(is_sideways_att, "true");
		if (bidi_level_att)
			bidi_level = atoi(bidi_level_att);

		font = xps_lookup_font(ctx, doc, base_uri, font_uri_att, style_att);
		if (!font)
			return;

		fz_var(text);
		fz_try(ctx)
		{
			text = xps_parse_glyphs_imp(ctx, doc, ctm, font, fz_atof(font_size_att),
					fz_atof(origin_x_att), fz_atof(origin_y_att),
					is_sideways, bidi_level, indices_att, unicode_att);
			area = fz_bound_text(ctx, text, NULL, ctm);
		}
		fz_always(ctx)
		{
			fz_drop_text(ctx, text);
			fz_drop_font(ctx, font);
		}
		fz_catch(ctx)
			fz_rethrow(ctx);

		xps_add_link(ctx, doc, area, base_uri, navigate_uri_att, link);
	}
}

static void
xps_load_links_in_canvas(fz_context *ctx, xps_document *doc, fz_matrix ctm,
		char *base_uri, xps_resource *dict, fz_xml *root, fz_link **link)
{
	xps_resource *new_dict = NULL;
	fz_xml *node;

	char *navigate_uri_att = fz_xml_att(root, "FixedPage.NavigateUri");
	char *transform_att = fz_xml_att(root, "RenderTransform");
	fz_xml *transform_tag = fz_xml_down(fz_xml_find_down(root, "Canvas.RenderTransform"));
	fz_xml *resource_tag = fz_xml_down(fz_xml_find_down(root, "Canvas.Resources"));

	if (resource_tag)
	{
		new_dict = xps_parse_resource_dictionary(ctx, doc, base_uri, resource_tag);
		if (new_dict)
		{
			new_dict->parent = dict;
			dict = new_dict;
		}
	}

	xps_resolve_resource_reference(ctx, doc, dict, &transform_att, &transform_tag, NULL);

	ctm = xps_parse_transform(ctx, doc, transform_att, transform_tag, ctm);

	if (navigate_uri_att)
		fz_warn(ctx, "FixedPage.NavigateUri attribute on Canvas element");

	for (node = fz_xml_down(root); node; node = fz_xml_next(node))
		xps_load_links_in_element(ctx, doc, ctm, base_uri, dict, node, link);

	if (new_dict)
		xps_drop_resource_dictionary(ctx, doc, new_dict);
}

static void
xps_load_links_in_element(fz_context *ctx, xps_document *doc, fz_matrix ctm, char *base_uri, xps_resource *dict, fz_xml *node, fz_link **link)
{
	if (fz_xml_is_tag(node, "Path"))
		xps_load_links_in_path(ctx, doc, ctm, base_uri, dict, node, link);
	else if (fz_xml_is_tag(node, "Glyphs"))
		xps_load_links_in_glyphs(ctx, doc, ctm, base_uri, dict, node, link);
	else if (fz_xml_is_tag(node, "Canvas"))
		xps_load_links_in_canvas(ctx, doc, ctm, base_uri, dict, node, link);
	else if (fz_xml_is_tag(node, "AlternateContent"))
	{
		node = xps_lookup_alternate_content(ctx, doc, node);
		if (node)
			xps_load_links_in_element(ctx, doc, ctm, base_uri, dict, node, link);
	}
}

static void
xps_load_links_in_fixed_page(fz_context *ctx, xps_document *doc, fz_matrix ctm, xps_page *page, fz_link **link)
{
	fz_xml *root, *node, *resource_tag;
	xps_resource *dict = NULL;
	char base_uri[1024];
	char *s;

	root = fz_xml_root(page->xml);

	if (!root)
		return;

	fz_strlcpy(base_uri, page->fix->name, sizeof base_uri);
	s = strrchr(base_uri, '/');
	if (s)
		s[1] = 0;

	resource_tag = fz_xml_down(fz_xml_find_down(root, "FixedPage.Resources"));
	if (resource_tag)
		dict = xps_parse_resource_dictionary(ctx, doc, base_uri, resource_tag);

	for (node = fz_xml_down(root); node; node = fz_xml_next(node))
		xps_load_links_in_element(ctx, doc, ctm, base_uri, dict, node, link);

	if (dict)
		xps_drop_resource_dictionary(ctx, doc, dict);
}

fz_link *
xps_load_links(fz_context *ctx, fz_page *page_)
{
	xps_page *page = (xps_page*)page_;
	fz_matrix ctm;
	fz_link *link = NULL;
	ctm = fz_scale(72.0f / 96.0f, 72.0f / 96.0f);
	xps_load_links_in_fixed_page(ctx, (xps_document*)page->super.doc, ctm, page, &link);
	return link;
}