Put SVGPreview into it's own file.

5 files changed, 594 insertions, 480 deletions

diff --git a/src/ui/CMakeLists.txt b/src/ui/CMakeLists.txt
index e9e8fb3e5..494e81206 100644
--- a/src/ui/CMakeLists.txt
+++ b/src/ui/CMakeLists.txt
@@ -104,7 +104,7 @@ set(ui_SRC
 	dialog/filedialog.cpp
 	dialog/filedialogimpl-gtkmm.cpp
 	dialog/fill-and-stroke.cpp
-    dialog/filter-editor.cpp
+        dialog/filter-editor.cpp
 	dialog/filter-effects-dialog.cpp
 	dialog/find.cpp
 	dialog/floating-behavior.cpp
@@ -137,6 +137,7 @@ set(ui_SRC
 	dialog/spellcheck.cpp
     dialog/styledialog.cpp
 	dialog/svg-fonts-dialog.cpp
+        dialog/svg-preview.cpp
 	dialog/swatches.cpp
 	dialog/symbols.cpp
 	dialog/tags.cpp
@@ -302,8 +303,9 @@ set(ui_SRC
 	dialog/print.h
 	dialog/prototype.h
 	dialog/spellcheck.h
-    dialog/styledialog.h
+        dialog/styledialog.h
 	dialog/svg-fonts-dialog.h
+        dialog/svg-preview.h
 	dialog/swatches.h
 	dialog/symbols.h
 	dialog/tags.h
diff --git a/src/ui/dialog/filedialogimpl-gtkmm.cpp b/src/ui/dialog/filedialogimpl-gtkmm.cpp
index b2fa87fe2..688b286b4 100644
--- a/src/ui/dialog/filedialogimpl-gtkmm.cpp
+++ b/src/ui/dialog/filedialogimpl-gtkmm.cpp
@@ -110,423 +110,6 @@ void findExpanderWidgets(Gtk::Container *parent, std::vector<Gtk::Expander *> &r
 
 
 /*#########################################################################
-### SVG Preview Widget
-#########################################################################*/
-
-bool SVGPreview::setDocument(SPDocument *doc)
-{
-    document = doc;
-
-    if (viewer) {
-        viewer->setDocument(document);
-    } else {
-        viewer = Gtk::manage(new Inkscape::UI::View::SVGViewWidget(document));
-        pack_start(*viewer, true, true);
-    }
-
-    show_all();
-
-    return true;
-}
-
-
-bool SVGPreview::setFileName(Glib::ustring &theFileName)
-{
-    Glib::ustring fileName = theFileName;
-
-    fileName = Glib::filename_to_utf8(fileName);
-
-    /**
-     * I don't know why passing false to keepalive is bad.  But it
-     * prevents the display of an svg with a non-ascii filename
-     */
-    SPDocument *doc = SPDocument::createNewDoc(fileName.c_str(), true);
-    if (!doc) {
-        g_warning("SVGView: error loading document '%s'\n", fileName.c_str());
-        return false;
-    }
-
-    setDocument(doc);
-
-    return true;
-}
-
-
-
-bool SVGPreview::setFromMem(char const *xmlBuffer)
-{
-    if (!xmlBuffer)
-        return false;
-
-    gint len = (gint)strlen(xmlBuffer);
-    SPDocument *doc = SPDocument::createNewDocFromMem(xmlBuffer, len, 0);
-    if (!doc) {
-        g_warning("SVGView: error loading buffer '%s'\n", xmlBuffer);
-        return false;
-    }
-
-    setDocument(doc);
-
-    return true;
-}
-
-
-
-void SVGPreview::showImage(Glib::ustring &theFileName)
-{
-    Glib::ustring fileName = theFileName;
-
-    // Let's get real width and height from SVG file. These are template
-    // files so we assume they are well formed.
-
-    // std::cout << "SVGPreview::showImage: " << theFileName << std::endl;
-    std::string width;
-    std::string height;
-
-    /*#####################################
-    # LET'S HAVE SOME FUN WITH SVG!
-    # Instead of just loading an image, why
-    # don't we make a lovely little svg and
-    # display it nicely?
-    #####################################*/
-
-    // Arbitrary size of svg doc -- rather 'portrait' shaped
-    gint previewWidth = 400;
-    gint previewHeight = 600;
-
-    // Get some image info. Smart pointer does not need to be deleted
-    Glib::RefPtr<Gdk::Pixbuf> img(nullptr);
-    try
-    {
-        img = Gdk::Pixbuf::create_from_file(fileName);
-    }
-    catch (const Glib::FileError &e)
-    {
-        g_message("caught Glib::FileError in SVGPreview::showImage");
-        return;
-    }
-    catch (const Gdk::PixbufError &e)
-    {
-        g_message("Gdk::PixbufError in SVGPreview::showImage");
-        return;
-    }
-    catch (...)
-    {
-        g_message("Caught ... in SVGPreview::showImage");
-        return;
-    }
-
-    gint imgWidth = img->get_width();
-    gint imgHeight = img->get_height();
-    
-    Glib::ustring svg = ".svg";
-    if (hasSuffix(fileName, svg)) {
-        std::ifstream input(theFileName.c_str());
-        if( !input ) {
-            std::cerr << "SVGPreview::showImage: Failed to open file: " << theFileName << std::endl;
-        } else {
-
-            std::string token;
-
-            Glib::MatchInfo match_info;
-            Glib::RefPtr<Glib::Regex> regex1 = Glib::Regex::create("width=\"(.*)\"");
-            Glib::RefPtr<Glib::Regex> regex2 = Glib::Regex::create("height=\"(.*)\"");
-     
-            while( !input.eof() && (height.empty() || width.empty()) ) {
-
-                input >> token;
-                // std::cout << "|" << token << "|" << std::endl;
-
-                if (regex1->match(token, match_info)) {
-                    width = match_info.fetch(1).raw();
-                }
-
-                if (regex2->match(token, match_info)) {
-                    height = match_info.fetch(1).raw();
-                }
-
-            }
-        }
-    }
-    
-    // TODO: replace int to string conversion with std::to_string when fully C++11 compliant
-    if (height.empty() || width.empty()) {
-        std::ostringstream s_width;
-        std::ostringstream s_height;
-        s_width << imgWidth;
-        s_height << imgHeight;
-        width = s_width.str();
-        height = s_height.str();
-    }
-
-    // Find the minimum scale to fit the image inside the preview area
-    double scaleFactorX = (0.9 * (double)previewWidth) / ((double)imgWidth);
-    double scaleFactorY = (0.9 * (double)previewHeight) / ((double)imgHeight);
-    double scaleFactor = scaleFactorX;
-    if (scaleFactorX > scaleFactorY)
-        scaleFactor = scaleFactorY;
-
-    // Now get the resized values
-    gint scaledImgWidth = (int)(scaleFactor * (double)imgWidth);
-    gint scaledImgHeight = (int)(scaleFactor * (double)imgHeight);
-
-    // center the image on the area
-    gint imgX = (previewWidth - scaledImgWidth) / 2;
-    gint imgY = (previewHeight - scaledImgHeight) / 2;
-
-    // wrap a rectangle around the image
-    gint rectX = imgX - 1;
-    gint rectY = imgY - 1;
-    gint rectWidth = scaledImgWidth + 2;
-    gint rectHeight = scaledImgHeight + 2;
-
-    // Our template.  Modify to taste
-    gchar const *xformat = R"A(
-<svg width="%d" height="%d"
-  xmlns="http://www.w3.org/2000/svg"
-  xmlns:xlink="http://www.w3.org/1999/xlink">
-  <rect width="100%" height="100%" style="fill:#eeeeee"/>
-  <image x="%d" y="%d" width="%d" height="%d" xlink:href="%s"/>
-  <rect  x="%d" y="%d" width="%d" height="%d" style="fill:none;stroke:black"/>
-  <text  x="50%" y="55%" style="font-family:sans-serif;font-size:24px;text-anchor:middle">%s x %s</text>
-</svg>
-)A";
-
-    // if (!Glib::get_charset()) //If we are not utf8
-    fileName = Glib::filename_to_utf8(fileName);
-
-    // Fill in the template
-    /* FIXME: Do proper XML quoting for fileName. */
-    gchar *xmlBuffer =
-        g_strdup_printf(xformat, previewWidth, previewHeight, imgX, imgY, scaledImgWidth, scaledImgHeight,
-                        fileName.c_str(), rectX, rectY, rectWidth, rectHeight, width.c_str(), height.c_str() );
-
-    // g_message("%s\n", xmlBuffer);
-
-    // now show it!
-    setFromMem(xmlBuffer);
-    g_free(xmlBuffer);
-}
-
-
-
-void SVGPreview::showNoPreview()
-{
-    // Are we already showing it?
-    if (showingNoPreview)
-        return;
-
-    // Our template.  Modify to taste
-    gchar const *xformat = R"B(
-<svg width="400" height="600"
-     xmlns="http://www.w3.org/2000/svg"
-     xmlns:xlink="http://www.w3.org/1999/xlink">
-  <g transform="translate(-160,90)" style="opacity:0.10">
-    <path style="fill:white"
-          d="M 397.64309 320.25301 L 280.39197 282.517 L 250.74227 124.83447 L 345.08225
-             29.146783 L 393.59996 46.667064 L 483.89679 135.61619 L 397.64309 320.25301 z"/>
-    <path d="M 476.95792 339.17168 C 495.78197 342.93607 499.54842 356.11361 495.78197 359.87802
-             C 492.01856 363.6434 482.6065 367.40781 475.07663 361.76014 C 467.54478
-             356.11361 467.54478 342.93607 476.95792 339.17168 z"
-             id="droplet01" />
-    <path d="M 286.46194 340.42914 C 284.6277 340.91835 269.30405 327.71337 257.16909 333.8338
-             C 245.03722 339.95336 236.89276 353.65666 248.22676 359.27982 C 259.56184 364.90298
-             267.66433 358.41867 277.60113 351.44119 C 287.53903 344.46477
-             287.18046 343.1206 286.46194 340.42914 z"
-             id= "droplet02"/>
-    <path d="M 510.35756 306.92856 C 520.59494 304.36879 544.24333 306.92856 540.47688 321.98634
-             C 536.71354 337.04806 504.71297 331.39827 484.00371 323.87156 C 482.12141
-             308.81083 505.53237 308.13423 510.35756 306.92856 z"
-             id="droplet03"/>
-    <path d="M 359.2403 21.362537 C 347.92693 21.362537 336.6347 25.683095 327.96556 34.35223 
-             L 173.87387 188.41466 C 165.37697 196.9114 161.1116 207.95813 160.94269 219.04577
-             L 160.88418 219.04577 C 160.88418 219.08524 160.94076 219.12322 160.94269 219.16279
-             C 160.94033 219.34888 160.88418 219.53256 160.88418 219.71865 L 161.14748 219.71865
-             C 164.0966 230.93917 240.29699 245.24198 248.79866 253.74346 C 261.63771 266.58263
-             199.5652 276.01151 212.4041 288.85074 C 225.24316 301.68979 289.99433 313.6933 302.8346
-             326.53254 C 315.67368 339.37161 276.5961 353.04289 289.43532 365.88196 C 302.27439
-             378.72118 345.40201 362.67257 337.5908 396.16198 C 354.92909 413.50026 391.10302
-             405.2208 415.32417 387.88252 C 428.16323 375.04345 390.6948 376.17577 403.53397
-             363.33668 C 416.37304 350.49745 448.78128 350.4282 476.08902 319.71589 C 465.09739
-             302.62116 429.10801 295.34136 441.94719 282.50217 C 454.78625 269.66311 479.74708
-             276.18423 533.60644 251.72479 C 559.89837 239.78398 557.72636 230.71459 557.62567
-             219.71865 C 557.62356 219.48727 557.62567 219.27892 557.62567 219.04577 L 557.56716
-             219.04577 C 557.3983 207.95812 553.10345 196.9114 544.60673 188.41466 L 390.54428
-             34.35223 C 381.87515 25.683095 370.55366 21.362537 359.2403 21.362537 z M 357.92378
-             41.402939 C 362.95327 41.533963 367.01541 45.368018 374.98006 50.530832 L 447.76915
-             104.50827 C 448.56596 105.02498 449.32484 105.564 450.02187 106.11735 C 450.7189 106.67062
-             451.3556 107.25745 451.95277 107.84347 C 452.54997 108.42842 453.09281 109.01553 453.59111
-             109.62808 C 454.08837 110.24052 454.53956 110.86661 454.93688 111.50048 C 455.33532 112.13538
-             455.69164 112.78029 455.9901 113.43137 C 456.28877 114.08363 456.52291 114.75639 456.7215
-             115.42078 C 456.92126 116.08419 457.08982 116.73973 457.18961 117.41019 C 457.28949
-             118.08184 457.33588 118.75535 457.33588 119.42886 L 414.21245 98.598549 L 409.9118
-             131.16055 L 386.18512 120.04324 L 349.55654 144.50131 L 335.54288 96.1703 L 317.4919
-             138.4453 L 267.08369 143.47735 L 267.63956 121.03795 C 267.63956 115.64823 296.69685
-             77.915899 314.39075 68.932902 L 346.77721 45.674327 C 351.55594 42.576634 354.90608
-             41.324327 357.92378 41.402939 z M 290.92738 261.61333 C 313.87149 267.56365 339.40299
-             275.37038 359.88393 275.50997 L 360.76161 284.72563 C 343.2235 282.91785 306.11346
-             274.45012 297.36372 269.98057 L 290.92738 261.61333 z"
-             id="mountainDroplet"/>
-  </g>
-  <text xml:space="preserve" x="200" y="320"
-        style="font-size:32px;font-weight:bold;text-anchor:middle">%s</text>
-</svg>
-)B";
-
-    // Fill in the template
-    gchar *xmlBuffer = g_strdup_printf(xformat, _("No preview"));
-
-    // g_message("%s\n", xmlBuffer);
-
-    // Now show it!
-    setFromMem(xmlBuffer);
-    g_free(xmlBuffer);
-    showingNoPreview = true;
-}
-
-
-/**
- * Inform the user that the svg file is too large to be displayed.
- * This does not check for sizes of embedded images (yet)
- */
-void SVGPreview::showTooLarge(long fileLength)
-{
-    // Our template.  Modify to taste
-    gchar const *xformat = R"C(
-<svg width="400" height="600"
-     xmlns="http://www.w3.org/2000/svg"
-     xmlns:xlink="http://www.w3.org/1999/xlink">
-  <g transform="translate(-160,90)" style="opacity:0.10">
-    <path style="fill:white"
-          d="M 397.64309 320.25301 L 280.39197 282.517 L 250.74227 124.83447 L 345.08225
-             29.146783 L 393.59996 46.667064 L 483.89679 135.61619 L 397.64309 320.25301 z"/>
-    <path d="M 476.95792 339.17168 C 495.78197 342.93607 499.54842 356.11361 495.78197 359.87802
-             C 492.01856 363.6434 482.6065 367.40781 475.07663 361.76014 C 467.54478
-             356.11361 467.54478 342.93607 476.95792 339.17168 z"
-             id="droplet01" />
-    <path d="M 286.46194 340.42914 C 284.6277 340.91835 269.30405 327.71337 257.16909 333.8338
-             C 245.03722 339.95336 236.89276 353.65666 248.22676 359.27982 C 259.56184 364.90298
-             267.66433 358.41867 277.60113 351.44119 C 287.53903 344.46477
-             287.18046 343.1206 286.46194 340.42914 z"
-             id= "droplet02"/>
-    <path d="M 510.35756 306.92856 C 520.59494 304.36879 544.24333 306.92856 540.47688 321.98634
-             C 536.71354 337.04806 504.71297 331.39827 484.00371 323.87156 C 482.12141
-             308.81083 505.53237 308.13423 510.35756 306.92856 z"
-             id="droplet03"/>
-    <path d="M 359.2403 21.362537 C 347.92693 21.362537 336.6347 25.683095 327.96556 34.35223 
-             L 173.87387 188.41466 C 165.37697 196.9114 161.1116 207.95813 160.94269 219.04577
-             L 160.88418 219.04577 C 160.88418 219.08524 160.94076 219.12322 160.94269 219.16279
-             C 160.94033 219.34888 160.88418 219.53256 160.88418 219.71865 L 161.14748 219.71865
-             C 164.0966 230.93917 240.29699 245.24198 248.79866 253.74346 C 261.63771 266.58263
-             199.5652 276.01151 212.4041 288.85074 C 225.24316 301.68979 289.99433 313.6933 302.8346
-             326.53254 C 315.67368 339.37161 276.5961 353.04289 289.43532 365.88196 C 302.27439
-             378.72118 345.40201 362.67257 337.5908 396.16198 C 354.92909 413.50026 391.10302
-             405.2208 415.32417 387.88252 C 428.16323 375.04345 390.6948 376.17577 403.53397
-             363.33668 C 416.37304 350.49745 448.78128 350.4282 476.08902 319.71589 C 465.09739
-             302.62116 429.10801 295.34136 441.94719 282.50217 C 454.78625 269.66311 479.74708
-             276.18423 533.60644 251.72479 C 559.89837 239.78398 557.72636 230.71459 557.62567
-             219.71865 C 557.62356 219.48727 557.62567 219.27892 557.62567 219.04577 L 557.56716
-             219.04577 C 557.3983 207.95812 553.10345 196.9114 544.60673 188.41466 L 390.54428
-             34.35223 C 381.87515 25.683095 370.55366 21.362537 359.2403 21.362537 z M 357.92378
-             41.402939 C 362.95327 41.533963 367.01541 45.368018 374.98006 50.530832 L 447.76915
-             104.50827 C 448.56596 105.02498 449.32484 105.564 450.02187 106.11735 C 450.7189 106.67062
-             451.3556 107.25745 451.95277 107.84347 C 452.54997 108.42842 453.09281 109.01553 453.59111
-             109.62808 C 454.08837 110.24052 454.53956 110.86661 454.93688 111.50048 C 455.33532 112.13538
-             455.69164 112.78029 455.9901 113.43137 C 456.28877 114.08363 456.52291 114.75639 456.7215
-             115.42078 C 456.92126 116.08419 457.08982 116.73973 457.18961 117.41019 C 457.28949
-             118.08184 457.33588 118.75535 457.33588 119.42886 L 414.21245 98.598549 L 409.9118
-             131.16055 L 386.18512 120.04324 L 349.55654 144.50131 L 335.54288 96.1703 L 317.4919
-             138.4453 L 267.08369 143.47735 L 267.63956 121.03795 C 267.63956 115.64823 296.69685
-             77.915899 314.39075 68.932902 L 346.77721 45.674327 C 351.55594 42.576634 354.90608
-             41.324327 357.92378 41.402939 z M 290.92738 261.61333 C 313.87149 267.56365 339.40299
-             275.37038 359.88393 275.50997 L 360.76161 284.72563 C 343.2235 282.91785 306.11346
-             274.45012 297.36372 269.98057 L 290.92738 261.61333 z"
-             id="mountainDroplet"/>
-  </g>
-  <text xml:space="preserve" x="200" y="280"
-        style="font-size:20px;font-weight:bold;text-anchor:middle">%.1f MB</text>
-  <text xml:space="preserve" x="200" y="360"
-        style="font-size:20px;font-weight:bold;text-anchor:middle">%s</text>
-</svg>
-)C";
-
-
-    // Fill in the template
-    double floatFileLength = ((double)fileLength) / 1048576.0;
-    // printf("%ld %f\n", fileLength, floatFileLength);
-
-    gchar *xmlBuffer =
-        g_strdup_printf(xformat, floatFileLength, _("Too large for preview"));
-
-    // g_message("%s\n", xmlBuffer);
-
-    // now show it!
-    setFromMem(xmlBuffer);
-    g_free(xmlBuffer);
-}
-
-bool SVGPreview::set(Glib::ustring &fileName, int dialogType)
-{
-
-    if (!Glib::file_test(fileName, Glib::FILE_TEST_EXISTS)) {
-        showNoPreview();
-        return false;
-    }
-
-    if (Glib::file_test(fileName, Glib::FILE_TEST_IS_DIR)) {
-        showNoPreview();
-        return false;
-    }
-
-    if (Glib::file_test(fileName, Glib::FILE_TEST_IS_REGULAR)) {
-        Glib::ustring fileNameUtf8 = Glib::filename_to_utf8(fileName);
-        gchar *fName = const_cast<gchar *>(
-            fileNameUtf8.c_str()); // const-cast probably not necessary? (not necessary on Windows version of stat())
-        GStatBuf info;
-        if (g_stat(fName, &info)) // stat returns 0 upon success
-        {
-            g_warning("SVGPreview::set() : %s : %s", fName, strerror(errno));
-            return false;
-        }
-        if (info.st_size > 0xA00000L) {
-            showingNoPreview = false;
-            showTooLarge(info.st_size);
-            return false;
-        }
-    }
-
-    Glib::ustring svg = ".svg";
-    Glib::ustring svgz = ".svgz";
-
-    if ((dialogType == SVG_TYPES || dialogType == IMPORT_TYPES) &&
-        (hasSuffix(fileName, svg) || hasSuffix(fileName, svgz))) {
-        bool retval = setFileName(fileName);
-        showingNoPreview = false;
-        return retval;
-    } else if (isValidImageFile(fileName)) {
-        showImage(fileName);
-        showingNoPreview = false;
-        return true;
-    } else {
-        showNoPreview();
-        return false;
-    }
-}
-
-
-SVGPreview::SVGPreview()
-    : document(nullptr)
-    , viewer(nullptr)
-    , showingNoPreview(false)
-{
-    set_size_request(200, 300);
-}
-
-SVGPreview::~SVGPreview()
-= default;
-
-
-/*#########################################################################
 ### F I L E     D I A L O G    B A S E    C L A S S
 #########################################################################*/
 
diff --git a/src/ui/dialog/filedialogimpl-gtkmm.h b/src/ui/dialog/filedialogimpl-gtkmm.h
index 9a351ff36..7a1061bb8 100644
--- a/src/ui/dialog/filedialogimpl-gtkmm.h
+++ b/src/ui/dialog/filedialogimpl-gtkmm.h
@@ -30,7 +30,7 @@
 #include <cerrno>
 
 #include "filedialog.h"
-
+#include "svg-preview.h"
 
 namespace Gtk {
 class Expander;
@@ -62,10 +62,6 @@ void
 findExpanderWidgets(Gtk::Container *parent,
                     std::vector<Gtk::Expander *> &result);
 
-/*#########################################################################
-### SVG Preview Widget
-#########################################################################*/
-
 class FileType
 {
     public:
@@ -76,62 +72,6 @@ class FileType
     Inkscape::Extension::Extension *extension;
 };
 
-/**
- * Simple class for displaying an SVG file in the "preview widget."
- * Currently, this is just a wrapper of the sp_svg_view Gtk widget.
- * Hopefully we will eventually replace with a pure Gtkmm widget.
- */
-class SVGPreview : public Gtk::VBox
-{
-public:
-
-    SVGPreview();
-
-    ~SVGPreview() override;
-
-    bool setDocument(SPDocument *doc);
-
-    bool setFileName(Glib::ustring &fileName);
-
-    bool setFromMem(char const *xmlBuffer);
-
-    bool set(Glib::ustring &fileName, int dialogType);
-
-    bool setURI(URI &uri);
-
-    /**
-     * Show image embedded in SVG
-     */
-    void showImage(Glib::ustring &fileName);
-
-    /**
-     * Show the "No preview" image
-     */
-    void showNoPreview();
-
-    /**
-     * Show the "Too large" image
-     */
-    void showTooLarge(long fileLength);
-
-private:
-    /**
-     * The svg document we are currently showing
-     */
-    SPDocument *document;
-
-    /**
-     * The sp_svg_view widget
-     */
-    Inkscape::UI::View::SVGViewWidget *viewer;
-
-    /**
-     * are we currently showing the "no preview" image?
-     */
-    bool showingNoPreview;
-
-};
-
 /*#########################################################################
 ### F I L E     D I A L O G    B A S E    C L A S S
 #########################################################################*/
diff --git a/src/ui/dialog/svg-preview.cpp b/src/ui/dialog/svg-preview.cpp
new file mode 100644
index 000000000..5f4bb2769
--- /dev/null
+++ b/src/ui/dialog/svg-preview.cpp
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/**
+ * @file
+ * Implementation of the file dialog interfaces defined in filedialogimpl.h.
+ */
+/* Authors:
+ *   Bob Jamison
+ *   Joel Holdsworth
+ *   Bruno Dilly
+ *   Other dudes from The Inkscape Organization
+ *   Abhishek Sharma
+ *
+ * Copyright (C) 2004-2007 Bob Jamison
+ * Copyright (C) 2006 Johan Engelen <johan@shouraizou.nl>
+ * Copyright (C) 2007-2008 Joel Holdsworth
+ * Copyright (C) 2004-2007 The Inkscape Organization
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <iostream>
+#include <fstream>
+
+#include <glibmm/i18n.h>
+#include <glib/gstdio.h>  // GStatBuf
+
+#include "svg-preview.h"
+
+#include "document.h"
+#include "ui/view/svg-view-widget.h"
+
+namespace Inkscape {
+namespace UI {
+namespace Dialog {
+
+/*#########################################################################
+### SVG Preview Widget
+#########################################################################*/
+
+bool SVGPreview::setDocument(SPDocument *doc)
+{
+    document = doc;
+
+    if (viewer) {
+        viewer->setDocument(document);
+    } else {
+        viewer = Gtk::manage(new Inkscape::UI::View::SVGViewWidget(document));
+        pack_start(*viewer, true, true);
+    }
+
+    show_all();
+
+    return true;
+}
+
+
+bool SVGPreview::setFileName(Glib::ustring &theFileName)
+{
+    Glib::ustring fileName = theFileName;
+
+    fileName = Glib::filename_to_utf8(fileName);
+
+    /**
+     * I don't know why passing false to keepalive is bad.  But it
+     * prevents the display of an svg with a non-ascii filename
+     */
+    SPDocument *doc = SPDocument::createNewDoc(fileName.c_str(), true);
+    if (!doc) {
+        g_warning("SVGView: error loading document '%s'\n", fileName.c_str());
+        return false;
+    }
+
+    setDocument(doc);
+
+    return true;
+}
+
+
+
+bool SVGPreview::setFromMem(char const *xmlBuffer)
+{
+    if (!xmlBuffer)
+        return false;
+
+    gint len = (gint)strlen(xmlBuffer);
+    SPDocument *doc = SPDocument::createNewDocFromMem(xmlBuffer, len, 0);
+    if (!doc) {
+        g_warning("SVGView: error loading buffer '%s'\n", xmlBuffer);
+        return false;
+    }
+
+    setDocument(doc);
+
+    return true;
+}
+
+
+
+void SVGPreview::showImage(Glib::ustring &theFileName)
+{
+    Glib::ustring fileName = theFileName;
+
+    // Let's get real width and height from SVG file. These are template
+    // files so we assume they are well formed.
+
+    // std::cout << "SVGPreview::showImage: " << theFileName << std::endl;
+    std::string width;
+    std::string height;
+
+    /*#####################################
+    # LET'S HAVE SOME FUN WITH SVG!
+    # Instead of just loading an image, why
+    # don't we make a lovely little svg and
+    # display it nicely?
+    #####################################*/
+
+    // Arbitrary size of svg doc -- rather 'portrait' shaped
+    gint previewWidth = 400;
+    gint previewHeight = 600;
+
+    // Get some image info. Smart pointer does not need to be deleted
+    Glib::RefPtr<Gdk::Pixbuf> img(nullptr);
+    try
+    {
+        img = Gdk::Pixbuf::create_from_file(fileName);
+    }
+    catch (const Glib::FileError &e)
+    {
+        g_message("caught Glib::FileError in SVGPreview::showImage");
+        return;
+    }
+    catch (const Gdk::PixbufError &e)
+    {
+        g_message("Gdk::PixbufError in SVGPreview::showImage");
+        return;
+    }
+    catch (...)
+    {
+        g_message("Caught ... in SVGPreview::showImage");
+        return;
+    }
+
+    gint imgWidth = img->get_width();
+    gint imgHeight = img->get_height();
+    
+    Glib::ustring svg = ".svg";
+    if (hasSuffix(fileName, svg)) {
+        std::ifstream input(theFileName.c_str());
+        if( !input ) {
+            std::cerr << "SVGPreview::showImage: Failed to open file: " << theFileName << std::endl;
+        } else {
+
+            std::string token;
+
+            Glib::MatchInfo match_info;
+            Glib::RefPtr<Glib::Regex> regex1 = Glib::Regex::create("width=\"(.*)\"");
+            Glib::RefPtr<Glib::Regex> regex2 = Glib::Regex::create("height=\"(.*)\"");
+     
+            while( !input.eof() && (height.empty() || width.empty()) ) {
+
+                input >> token;
+                // std::cout << "|" << token << "|" << std::endl;
+
+                if (regex1->match(token, match_info)) {
+                    width = match_info.fetch(1).raw();
+                }
+
+                if (regex2->match(token, match_info)) {
+                    height = match_info.fetch(1).raw();
+                }
+
+            }
+        }
+    }
+    
+    // TODO: replace int to string conversion with std::to_string when fully C++11 compliant
+    if (height.empty() || width.empty()) {
+        std::ostringstream s_width;
+        std::ostringstream s_height;
+        s_width << imgWidth;
+        s_height << imgHeight;
+        width = s_width.str();
+        height = s_height.str();
+    }
+
+    // Find the minimum scale to fit the image inside the preview area
+    double scaleFactorX = (0.9 * (double)previewWidth) / ((double)imgWidth);
+    double scaleFactorY = (0.9 * (double)previewHeight) / ((double)imgHeight);
+    double scaleFactor = scaleFactorX;
+    if (scaleFactorX > scaleFactorY)
+        scaleFactor = scaleFactorY;
+
+    // Now get the resized values
+    gint scaledImgWidth = (int)(scaleFactor * (double)imgWidth);
+    gint scaledImgHeight = (int)(scaleFactor * (double)imgHeight);
+
+    // center the image on the area
+    gint imgX = (previewWidth - scaledImgWidth) / 2;
+    gint imgY = (previewHeight - scaledImgHeight) / 2;
+
+    // wrap a rectangle around the image
+    gint rectX = imgX - 1;
+    gint rectY = imgY - 1;
+    gint rectWidth = scaledImgWidth + 2;
+    gint rectHeight = scaledImgHeight + 2;
+
+    // Our template.  Modify to taste
+    gchar const *xformat = R"A(
+<svg width="%d" height="%d"
+  xmlns="http://www.w3.org/2000/svg"
+  xmlns:xlink="http://www.w3.org/1999/xlink">
+  <rect width="100%" height="100%" style="fill:#eeeeee"/>
+  <image x="%d" y="%d" width="%d" height="%d" xlink:href="%s"/>
+  <rect  x="%d" y="%d" width="%d" height="%d" style="fill:none;stroke:black"/>
+  <text  x="50%" y="55%" style="font-family:sans-serif;font-size:24px;text-anchor:middle">%s x %s</text>
+</svg>
+)A";
+
+    // if (!Glib::get_charset()) //If we are not utf8
+    fileName = Glib::filename_to_utf8(fileName);
+
+    // Fill in the template
+    /* FIXME: Do proper XML quoting for fileName. */
+    gchar *xmlBuffer =
+        g_strdup_printf(xformat, previewWidth, previewHeight, imgX, imgY, scaledImgWidth, scaledImgHeight,
+                        fileName.c_str(), rectX, rectY, rectWidth, rectHeight, width.c_str(), height.c_str() );
+
+    // g_message("%s\n", xmlBuffer);
+
+    // now show it!
+    setFromMem(xmlBuffer);
+    g_free(xmlBuffer);
+}
+
+
+
+void SVGPreview::showNoPreview()
+{
+    // Are we already showing it?
+    if (showingNoPreview)
+        return;
+
+    // Our template.  Modify to taste
+    gchar const *xformat = R"B(
+<svg width="400" height="600"
+     xmlns="http://www.w3.org/2000/svg"
+     xmlns:xlink="http://www.w3.org/1999/xlink">
+  <g transform="translate(-160,90)" style="opacity:0.10">
+    <path style="fill:white"
+          d="M 397.64309 320.25301 L 280.39197 282.517 L 250.74227 124.83447 L 345.08225
+             29.146783 L 393.59996 46.667064 L 483.89679 135.61619 L 397.64309 320.25301 z"/>
+    <path d="M 476.95792 339.17168 C 495.78197 342.93607 499.54842 356.11361 495.78197 359.87802
+             C 492.01856 363.6434 482.6065 367.40781 475.07663 361.76014 C 467.54478
+             356.11361 467.54478 342.93607 476.95792 339.17168 z"
+             id="droplet01" />
+    <path d="M 286.46194 340.42914 C 284.6277 340.91835 269.30405 327.71337 257.16909 333.8338
+             C 245.03722 339.95336 236.89276 353.65666 248.22676 359.27982 C 259.56184 364.90298
+             267.66433 358.41867 277.60113 351.44119 C 287.53903 344.46477
+             287.18046 343.1206 286.46194 340.42914 z"
+             id= "droplet02"/>
+    <path d="M 510.35756 306.92856 C 520.59494 304.36879 544.24333 306.92856 540.47688 321.98634
+             C 536.71354 337.04806 504.71297 331.39827 484.00371 323.87156 C 482.12141
+             308.81083 505.53237 308.13423 510.35756 306.92856 z"
+             id="droplet03"/>
+    <path d="M 359.2403 21.362537 C 347.92693 21.362537 336.6347 25.683095 327.96556 34.35223 
+             L 173.87387 188.41466 C 165.37697 196.9114 161.1116 207.95813 160.94269 219.04577
+             L 160.88418 219.04577 C 160.88418 219.08524 160.94076 219.12322 160.94269 219.16279
+             C 160.94033 219.34888 160.88418 219.53256 160.88418 219.71865 L 161.14748 219.71865
+             C 164.0966 230.93917 240.29699 245.24198 248.79866 253.74346 C 261.63771 266.58263
+             199.5652 276.01151 212.4041 288.85074 C 225.24316 301.68979 289.99433 313.6933 302.8346
+             326.53254 C 315.67368 339.37161 276.5961 353.04289 289.43532 365.88196 C 302.27439
+             378.72118 345.40201 362.67257 337.5908 396.16198 C 354.92909 413.50026 391.10302
+             405.2208 415.32417 387.88252 C 428.16323 375.04345 390.6948 376.17577 403.53397
+             363.33668 C 416.37304 350.49745 448.78128 350.4282 476.08902 319.71589 C 465.09739
+             302.62116 429.10801 295.34136 441.94719 282.50217 C 454.78625 269.66311 479.74708
+             276.18423 533.60644 251.72479 C 559.89837 239.78398 557.72636 230.71459 557.62567
+             219.71865 C 557.62356 219.48727 557.62567 219.27892 557.62567 219.04577 L 557.56716
+             219.04577 C 557.3983 207.95812 553.10345 196.9114 544.60673 188.41466 L 390.54428
+             34.35223 C 381.87515 25.683095 370.55366 21.362537 359.2403 21.362537 z M 357.92378
+             41.402939 C 362.95327 41.533963 367.01541 45.368018 374.98006 50.530832 L 447.76915
+             104.50827 C 448.56596 105.02498 449.32484 105.564 450.02187 106.11735 C 450.7189 106.67062
+             451.3556 107.25745 451.95277 107.84347 C 452.54997 108.42842 453.09281 109.01553 453.59111
+             109.62808 C 454.08837 110.24052 454.53956 110.86661 454.93688 111.50048 C 455.33532 112.13538
+             455.69164 112.78029 455.9901 113.43137 C 456.28877 114.08363 456.52291 114.75639 456.7215
+             115.42078 C 456.92126 116.08419 457.08982 116.73973 457.18961 117.41019 C 457.28949
+             118.08184 457.33588 118.75535 457.33588 119.42886 L 414.21245 98.598549 L 409.9118
+             131.16055 L 386.18512 120.04324 L 349.55654 144.50131 L 335.54288 96.1703 L 317.4919
+             138.4453 L 267.08369 143.47735 L 267.63956 121.03795 C 267.63956 115.64823 296.69685
+             77.915899 314.39075 68.932902 L 346.77721 45.674327 C 351.55594 42.576634 354.90608
+             41.324327 357.92378 41.402939 z M 290.92738 261.61333 C 313.87149 267.56365 339.40299
+             275.37038 359.88393 275.50997 L 360.76161 284.72563 C 343.2235 282.91785 306.11346
+             274.45012 297.36372 269.98057 L 290.92738 261.61333 z"
+             id="mountainDroplet"/>
+  </g>
+  <text xml:space="preserve" x="200" y="320"
+        style="font-size:32px;font-weight:bold;text-anchor:middle">%s</text>
+</svg>
+)B";
+
+    // Fill in the template
+    gchar *xmlBuffer = g_strdup_printf(xformat, _("No preview"));
+
+    // g_message("%s\n", xmlBuffer);
+
+    // Now show it!
+    setFromMem(xmlBuffer);
+    g_free(xmlBuffer);
+    showingNoPreview = true;
+}
+
+
+/**
+ * Inform the user that the svg file is too large to be displayed.
+ * This does not check for sizes of embedded images (yet)
+ */
+void SVGPreview::showTooLarge(long fileLength)
+{
+    // Our template.  Modify to taste
+    gchar const *xformat = R"C(
+<svg width="400" height="600"
+     xmlns="http://www.w3.org/2000/svg"
+     xmlns:xlink="http://www.w3.org/1999/xlink">
+  <g transform="translate(-160,90)" style="opacity:0.10">
+    <path style="fill:white"
+          d="M 397.64309 320.25301 L 280.39197 282.517 L 250.74227 124.83447 L 345.08225
+             29.146783 L 393.59996 46.667064 L 483.89679 135.61619 L 397.64309 320.25301 z"/>
+    <path d="M 476.95792 339.17168 C 495.78197 342.93607 499.54842 356.11361 495.78197 359.87802
+             C 492.01856 363.6434 482.6065 367.40781 475.07663 361.76014 C 467.54478
+             356.11361 467.54478 342.93607 476.95792 339.17168 z"
+             id="droplet01" />
+    <path d="M 286.46194 340.42914 C 284.6277 340.91835 269.30405 327.71337 257.16909 333.8338
+             C 245.03722 339.95336 236.89276 353.65666 248.22676 359.27982 C 259.56184 364.90298
+             267.66433 358.41867 277.60113 351.44119 C 287.53903 344.46477
+             287.18046 343.1206 286.46194 340.42914 z"
+             id= "droplet02"/>
+    <path d="M 510.35756 306.92856 C 520.59494 304.36879 544.24333 306.92856 540.47688 321.98634
+             C 536.71354 337.04806 504.71297 331.39827 484.00371 323.87156 C 482.12141
+             308.81083 505.53237 308.13423 510.35756 306.92856 z"
+             id="droplet03"/>
+    <path d="M 359.2403 21.362537 C 347.92693 21.362537 336.6347 25.683095 327.96556 34.35223 
+             L 173.87387 188.41466 C 165.37697 196.9114 161.1116 207.95813 160.94269 219.04577
+             L 160.88418 219.04577 C 160.88418 219.08524 160.94076 219.12322 160.94269 219.16279
+             C 160.94033 219.34888 160.88418 219.53256 160.88418 219.71865 L 161.14748 219.71865
+             C 164.0966 230.93917 240.29699 245.24198 248.79866 253.74346 C 261.63771 266.58263
+             199.5652 276.01151 212.4041 288.85074 C 225.24316 301.68979 289.99433 313.6933 302.8346
+             326.53254 C 315.67368 339.37161 276.5961 353.04289 289.43532 365.88196 C 302.27439
+             378.72118 345.40201 362.67257 337.5908 396.16198 C 354.92909 413.50026 391.10302
+             405.2208 415.32417 387.88252 C 428.16323 375.04345 390.6948 376.17577 403.53397
+             363.33668 C 416.37304 350.49745 448.78128 350.4282 476.08902 319.71589 C 465.09739
+             302.62116 429.10801 295.34136 441.94719 282.50217 C 454.78625 269.66311 479.74708
+             276.18423 533.60644 251.72479 C 559.89837 239.78398 557.72636 230.71459 557.62567
+             219.71865 C 557.62356 219.48727 557.62567 219.27892 557.62567 219.04577 L 557.56716
+             219.04577 C 557.3983 207.95812 553.10345 196.9114 544.60673 188.41466 L 390.54428
+             34.35223 C 381.87515 25.683095 370.55366 21.362537 359.2403 21.362537 z M 357.92378
+             41.402939 C 362.95327 41.533963 367.01541 45.368018 374.98006 50.530832 L 447.76915
+             104.50827 C 448.56596 105.02498 449.32484 105.564 450.02187 106.11735 C 450.7189 106.67062
+             451.3556 107.25745 451.95277 107.84347 C 452.54997 108.42842 453.09281 109.01553 453.59111
+             109.62808 C 454.08837 110.24052 454.53956 110.86661 454.93688 111.50048 C 455.33532 112.13538
+             455.69164 112.78029 455.9901 113.43137 C 456.28877 114.08363 456.52291 114.75639 456.7215
+             115.42078 C 456.92126 116.08419 457.08982 116.73973 457.18961 117.41019 C 457.28949
+             118.08184 457.33588 118.75535 457.33588 119.42886 L 414.21245 98.598549 L 409.9118
+             131.16055 L 386.18512 120.04324 L 349.55654 144.50131 L 335.54288 96.1703 L 317.4919
+             138.4453 L 267.08369 143.47735 L 267.63956 121.03795 C 267.63956 115.64823 296.69685
+             77.915899 314.39075 68.932902 L 346.77721 45.674327 C 351.55594 42.576634 354.90608
+             41.324327 357.92378 41.402939 z M 290.92738 261.61333 C 313.87149 267.56365 339.40299
+             275.37038 359.88393 275.50997 L 360.76161 284.72563 C 343.2235 282.91785 306.11346
+             274.45012 297.36372 269.98057 L 290.92738 261.61333 z"
+             id="mountainDroplet"/>
+  </g>
+  <text xml:space="preserve" x="200" y="280"
+        style="font-size:20px;font-weight:bold;text-anchor:middle">%.1f MB</text>
+  <text xml:space="preserve" x="200" y="360"
+        style="font-size:20px;font-weight:bold;text-anchor:middle">%s</text>
+</svg>
+)C";
+
+
+    // Fill in the template
+    double floatFileLength = ((double)fileLength) / 1048576.0;
+    // printf("%ld %f\n", fileLength, floatFileLength);
+
+    gchar *xmlBuffer =
+        g_strdup_printf(xformat, floatFileLength, _("Too large for preview"));
+
+    // g_message("%s\n", xmlBuffer);
+
+    // now show it!
+    setFromMem(xmlBuffer);
+    g_free(xmlBuffer);
+}
+
+bool SVGPreview::set(Glib::ustring &fileName, int dialogType)
+{
+
+    if (!Glib::file_test(fileName, Glib::FILE_TEST_EXISTS)) {
+        showNoPreview();
+        return false;
+    }
+
+    if (Glib::file_test(fileName, Glib::FILE_TEST_IS_DIR)) {
+        showNoPreview();
+        return false;
+    }
+
+    if (Glib::file_test(fileName, Glib::FILE_TEST_IS_REGULAR)) {
+        Glib::ustring fileNameUtf8 = Glib::filename_to_utf8(fileName);
+        gchar *fName = const_cast<gchar *>(
+            fileNameUtf8.c_str()); // const-cast probably not necessary? (not necessary on Windows version of stat())
+        GStatBuf info;
+        if (g_stat(fName, &info)) // stat returns 0 upon success
+        {
+            g_warning("SVGPreview::set() : %s : %s", fName, strerror(errno));
+            return false;
+        }
+        if (info.st_size > 0xA00000L) {
+            showingNoPreview = false;
+            showTooLarge(info.st_size);
+            return false;
+        }
+    }
+
+    Glib::ustring svg = ".svg";
+    Glib::ustring svgz = ".svgz";
+
+    if ((dialogType == SVG_TYPES || dialogType == IMPORT_TYPES) &&
+        (hasSuffix(fileName, svg) || hasSuffix(fileName, svgz))) {
+        bool retval = setFileName(fileName);
+        showingNoPreview = false;
+        return retval;
+    } else if (isValidImageFile(fileName)) {
+        showImage(fileName);
+        showingNoPreview = false;
+        return true;
+    } else {
+        showNoPreview();
+        return false;
+    }
+}
+
+
+SVGPreview::SVGPreview()
+    : document(nullptr)
+    , viewer(nullptr)
+    , showingNoPreview(false)
+{
+    set_size_request(200, 300);
+}
+
+SVGPreview::~SVGPreview()
+= default;
+
+} // namespace Dialog
+} // namespace UI
+} // namespace Inkscape
+
+/*
+  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 :
+
diff --git a/src/ui/dialog/svg-preview.h b/src/ui/dialog/svg-preview.h
new file mode 100644
index 000000000..d70bdd7b2
--- /dev/null
+++ b/src/ui/dialog/svg-preview.h
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * @brief Implementation of the file dialog interfaces defined in filedialogimpl.h
+ */
+/* Authors:
+ *   Bob Jamison
+ *   Johan Engelen <johan@shouraizou.nl>
+ *   Joel Holdsworth
+ *   Bruno Dilly
+ *   Other dudes from The Inkscape Organization
+ *
+ * Copyright (C) 2004-2008 Authors
+ * Copyright (C) 2004-2007 The Inkscape Organization
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef __SVG_PREVIEW_H__
+#define __SVG_PREIVEW_H__
+
+//Gtk includes
+#include <gtkmm.h>
+
+//General includes
+#include <unistd.h>
+#include <sys/stat.h>
+#include <cerrno>
+
+#include "filedialog.h"
+
+
+namespace Gtk {
+class Expander;
+}
+
+namespace Inkscape {
+  class URI;
+
+namespace UI {
+
+namespace View {
+  class SVGViewWidget;
+}
+
+namespace Dialog {
+
+/*#########################################################################
+### SVG Preview Widget
+#########################################################################*/
+
+/**
+ * Simple class for displaying an SVG file in the "preview widget."
+ * Currently, this is just a wrapper of the sp_svg_view Gtk widget.
+ * Hopefully we will eventually replace with a pure Gtkmm widget.
+ */
+class SVGPreview : public Gtk::VBox
+{
+public:
+
+    SVGPreview();
+
+    ~SVGPreview() override;
+
+    bool setDocument(SPDocument *doc);
+
+    bool setFileName(Glib::ustring &fileName);
+
+    bool setFromMem(char const *xmlBuffer);
+
+    bool set(Glib::ustring &fileName, int dialogType);
+
+    bool setURI(URI &uri);
+
+    /**
+     * Show image embedded in SVG
+     */
+    void showImage(Glib::ustring &fileName);
+
+    /**
+     * Show the "No preview" image
+     */
+    void showNoPreview();
+
+    /**
+     * Show the "Too large" image
+     */
+    void showTooLarge(long fileLength);
+
+private:
+    /**
+     * The svg document we are currently showing
+     */
+    SPDocument *document;
+
+    /**
+     * The sp_svg_view widget
+     */
+    Inkscape::UI::View::SVGViewWidget *viewer;
+
+    /**
+     * are we currently showing the "no preview" image?
+     */
+    bool showingNoPreview;
+
+};
+
+
+} // namespace Dialog
+} // namespace UI
+} // namespace Inkscape
+
+#endif /*__SVG_PREVIEW_H__*/
+
+/*
+  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 :