diff --git a/COPYING.txt b/COPYING.txt
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--- /dev/null
+++ b/COPYING.txt
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The GNU General Public License is a free, copyleft license for
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+ The licenses for most software and other practical works are designed
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+GNU General Public License for most of our software; it applies also to
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+ When we speak of free software, we are referring to freedom, not
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+ Developers that use the GNU GPL protect your rights with two steps:
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+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/Info.plist b/Info.plist
new file mode 100644
index 0000000..71930ba
--- /dev/null
+++ b/Info.plist
@@ -0,0 +1,44 @@
+
+
+
+
+ CFBundleGetInfoString
+ ramanpdf
+ CFBundleExecutable
+ ramanpdf
+ CFBundleIdentifier
+ org.ramanpdf.www
+ CFBundleDisplayName
+ ramanpdf
+ CFBundleName
+ ramanpdf
+ CFBundleIconFile
+ ramanpdf.icns
+ CFBundleDocumentTypes
+
+
+ CFBundleTypeName
+ PDF
+ CFBundleTypeRole
+ Viewer
+ LSItemContentTypes
+
+ com.adobe.pdf
+
+ LSHandlerRank
+ Alternate
+
+
+ CFBundleShortVersionString
+ 0.01
+ CFBundleInfoDictionaryVersion
+ 6.0
+ CFBundlePackageType
+ APPL
+ IFMajorVersion
+ 0
+ IFMinorVersion
+ 1
+
+
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..169404e
--- /dev/null
+++ b/README.md
@@ -0,0 +1,185 @@
+# README
+A toy PDF viewer I made as a learning project -- `ramanpdf.app`.
+
+Since I do not have the xcode IDE, I explored alternatives and found
+the trio of Vala compiler, GTK4, and Poppler.
+This project took me on a happy journey of discovery.
+To share the lessons I learnt, I put it here on github for like-minded
+people who are possibly in search of a similar solution.
+
+## What I wanted
+1. A PDF viewer with simple key-press control.
+2. GUI application that runs on OSX Big Sur without showing the terminal.
+3. Able to call it from OSX Finder's "Open With" context menu.
+4. Can switch between a "light" and a "dark" mode.
+5. Can be put on one side of the screen, so that I can take notes with
+ another app on the other side.
+6. Able to rotate and zoom the pdf page.
+
+## Features
+1. No menu.
+2. Key-press commands:
+ * 'o' opens a FileDialog to choose the PDF file.
+ * '=' to zoom in.
+ * '-' to zoom out.
+ * '0' to reset zoom.
+ * ' ' (space) to cycle forward through the pages.
+ * 't' to rotate 90 degrees clockwise each time.
+ * 'd' to toggle between color and grayscale.
+ * 'i' to flip color or grayscale to their opposites.
+ * 'q' to quit.
+3. Scrolling is restricted to panning the one page within the window.
+ Scrollbar(s) appear when the page is too big for the window.
+4. Grey background when no file; or when PDF is a damaged file (or not PDF).
+5. Handles opening of file from Finder (ie., it is *registered*).
+6. Does not open multiple windows.
+ The single application window is recycled for each new file opened.
+7. User can see highlights (but cannot add new highlight).
+8. Window title can be empty, a document file name, or an error message.
+9. Resizable window.
+
+## Limitations
+1. Not app-sandboxed, hardened, notarised, or evaluated by gatekeeper.
+2. No security measures to protect against cyber-attacks.
+3. Not much error-handling.
+4. A lag when rendering a 'busy' page (colorful or large image).
+5. No key-press command to go back one page.
+6. Content does not resize to window (ie., cannot zoom by resizing window).
+7. User cannot select text or images for copying.
+8. User cannot add highlights, annotations, bookmarks, or anything.
+9. Does not respond to clicking URL inside the pdf.
+10. Does not support "drag and drop".
+11. In essence, whatever not mentioned in "Features" above.
+12. Not tested on any OS besides Apple OSX 11.7.10 (Big Sur).
+
+## Ingredients
+1. Compiler, tools, and libraries: Vala, GTK4, Poppler, pkg-config.
+2. Code: `ramanpdf.vala`, `ramanpdf.icns`, `Info.plist`, `makefile`.
+3. Optional: `svg2icns.sh` and `ramanpdf.svg`.
+
+## Mac App Bundling
+* The makefile makes the app (`ramanpdf`) and packages it into
+ an app bundle (`ramanpdf.app`).
+ * An "App Bundle" is the result of Apple's way of arranging an app,
+ its linked libraries, app icon, and "configuration" file (pList) into
+ a folder structure with a `.app` suffix -- that we have come to know
+ as an OSX Application.
+ * When a app bundle is run, it no longer shows a Terminal window.
+ * The makefile simply copies `ramanpdf`, `ramanpdf.icns`, and `Info.plist`;
+ and pastes them into the folder structure of an app bundle.
+ * It also copies the relevant dynamic libraries (of GTK4 and Poppler)
+ and pastes them to the folder structure; and finally tells `ramanpdf`
+ how to find them within the app bundle.
+ * To tell `ramanpdf` how to find the libraries, it uses OSX's `otool` to
+ find the libraries that `ramanpdf` links to, then it selects the ones
+ that are not built-in (which would be the GTK and Poppler libraries),
+ and uses OSX's `install_name_tool` to tell `ramanpdf` about the new
+ paths of the libraries.
+ * Although 'otool' and 'install_name_tool' are both built-in OSX programs,
+ I am not certain whether this part of the make process will work for
+ other OSX versions.
+ (Easy to check whether your OSX have these, by typing `which otool` in
+ the Terminal. Similarly, for install_name_tool).
+ * The `list.txt` is generated by the makefile and it lists all the
+ libraries that are to be copied to the app bundle.
+* Accessories:
+ * Inkscape (for designing the app bundle icon as an Inkscape SVG file).
+ * zsh shell file [svg2icns.sh](
+ https://gist.github.com/ikey4u/659f38b4d7b3484d0b55de85a55a8154)
+ (for making icns file from the SVG above).
+ It uses Inkscape to convert the SVG into multiple PNG files, each of
+ a different size, and after that it uses OSX built-in `iconutil` to
+ group these PNG files into a single ICNS file.
+
+## How I built the application and the OSX app bundle
+1. Set up:
+ * I developed on OSX Big Sur (and not sure if it works on others).
+ * I used [homebrew](https://brew.sh) to install Vala, GTK4, and Poppler.
+ * I used [homebrew](https://brew.sh) to install `pkg-config`.
+ * Since I am using homebrew's version of pkg-config, I must export a
+ PKG_CONFIG_PATH environment variable for each of `libffi` and `glib`
+ to ensure pkg-config looks for the correct libraries in the correct
+ paths.
+ This has been incorporated in the makefile.
+ * Optional (for designing the icon SVG file):
+ I used Inkscape to make `ramanpdf.svg`.
+ Then I used `svg2icns.sh` to make `ramanpdf.icns`.
+2. Build:
+ * I used `make` instead of the `meson` and `ninja` that came with the
+ homebrew installation of `gtk4`.
+ (It might be easier to build by using the latter two but I am less
+ familiar with them than with `make`).
+ * Run `make` to build *everything*:
+ * `ramanpdf` - this runs with Terminal showing.
+ * `list.txt` - this is just a by-product of the build process.
+ * `ramanpdf.app` - this runs without Terminal showing.
+ * Instead, to just build the app that can be called from Terminal
+ and not for registering with OSX Finder, run `make ramanpdf`.
+ If things go well, a file named `ramanpdf` should appear.
+ You can then run it using the command `./ramanpdf` in Terminal.
+ Or, double-click on `ramanpdf` in Finder.
+ * The Terminal `ramanpdf` accepts a single argument of file name.
+ For example, run `./ramanpdf filename.pdf` to open said pdf file.
+
+## Install App Bundle and Register with OSX Finder
+1. Copy `ramanpdf.app` to the Applications folder to install.
+ And then double-click on it (ie., run it inside the Applications folder)
+ to register.
+2. I take it as registered when the app window appears.
+3. If registration went well, you should be able to see `ramanpdf.app` in
+ the context menu (test right-click on a file in Finder - look under
+ "Open With").
+
+## Clean-up
+1. To start over, run `make clean` to remove everything that was made.
+2. The 'ramanpdf.app' can be removed from the Applications folder
+ the usual way if you do not want it anymore -- just delete it.
+
+## Release
+I have uploaded my build of `ramanpdf` and `ramanpdf.app`.
+But your OSX *might* say it comes from another computer and refuse to run
+it for security reasons.
+I mean, I have not tested on other people's Apple computers, so that is
+why I included the word "might".
+
+My OSX did not complain about security, but probably because I build the
+App Bundle on my OSX.
+If you build it yourself on your own OSX, your OSX security *might* not
+complain.
+
+## Acknowledgements
+1. [Vala](https://vala-language.org) for taking the pain out of working
+ with C coding.
+2. [GTK4](https://www.gtk.org) for making the GUI look like the native
+ OSX GUI and can be easily registered with OSX Finder.
+3. [Poppler](https://poppler.freedesktop.org) for making it so easy to
+ incorporate PDF rendering into GTK4, using the poppler-glib API.
+4. [Inkscape](https://inkscape.org) for making it possible to quickly
+ design a simple image file in SVG.
+5. Many thanks to zhq/ikey4u, the author of [svg2icns.sh](
+ https://gist.github.com/ikey4u/659f38b4d7b3484d0b55de85a55a8154)
+ for a wonderful shell script that streamlines my icon design workflow to
+ Inkscape and `iconutil` only.
+6. This [GNOME discourse](
+ https://discourse.gnome.org/t/using-filedialog-in-vala/15376) pointed
+ the way how to use the file dialog in Vala.
+7. [Stackoverflow.com](https://stackoverflow.com).
+8. [Apple StackExchange](https://apple.stackexchange.com).
+9. Many other sources on the web that I have not mentioned here.
+
+## Bugs
+1. Poppler (Cairo backend) [bug](
+ https://gitlab.freedesktop.org/poppler/poppler/-/issues/1443)
+ related to an image in PDF file.
+
+
+## DISCLAIMER
+I am not a professional programmer; and I do not have any real software
+industry exposure or experience.
+I do not know what the relevant standards are; and I have not done strong
+testing of this code and of this application.
+As a consequence, I cannot guarantee that this application or the code
+provided here is safe, error-free, or even harmless.
+
+Use at your own risk!
+
diff --git a/makefile b/makefile
new file mode 100644
index 0000000..c83f4a6
--- /dev/null
+++ b/makefile
@@ -0,0 +1,29 @@
+DEST_DIR := ramanpdf.app/Contents/MacOS
+
+.PHONY: clean copying
+
+copying: list.txt ramanpdf
+ cp ramanpdf $(DEST_DIR)/ramanpdf
+ for lib in $$(cat list.txt); do \
+ APP_LIB=$$(basename $$lib) ; \
+ cp $$lib $(DEST_DIR)/ ; \
+ install_name_tool -change $$lib @executable_path/$$APP_LIB $(DEST_DIR)/ramanpdf ; \
+ done
+ cp Info.plist ramanpdf.app/Contents/Info.plist
+ mkdir ramanpdf.app/Contents/Resources
+ cp ramanpdf.icns ramanpdf.app/Contents/Resources/ramanpdf.icns
+
+list.txt: ramanpdf
+ $(eval USR_OPT=$(shell otool -L ramanpdf | cut -f 1 -d " " | tr -d "[:blank:]" | grep '^\/usr\/local\/opt' ))
+ echo $(USR_OPT) > list.txt
+
+ramanpdf: ramanpdf.vala
+ export PKG_CONFIG_PATH=$$PKG_CONFIG_PATH:/usr/local/opt/libffi/lib/pkgconfig ; \
+ export PKG_CONFIG_PATH=$$PKG_CONFIG_PATH:/usr/local/Cellar/glib/2.78.0/lib/pkgconfig; \
+ valac --Xcc=-headerpad_max_install_names --pkg poppler-glib --pkg glib-2.0 --pkg gtk4 -o ramanpdf ramanpdf.vala
+ mkdir -p $(DEST_DIR)
+
+clean:
+ rm -f ramanpdf
+ rm -fr ramanpdf.app
+ rm -f list.txt
diff --git a/ramanpdf.icns b/ramanpdf.icns
new file mode 100644
index 0000000..b57bcf8
Binary files /dev/null and b/ramanpdf.icns differ
diff --git a/ramanpdf.vala b/ramanpdf.vala
new file mode 100644
index 0000000..48b16d1
--- /dev/null
+++ b/ramanpdf.vala
@@ -0,0 +1,318 @@
+/*
+
+ramanpdf.vala
+
+Copyright 2023 Roland Chee
+
+This program is distributed under the terms of the
+GNU General Public Licence.
+
+This program is free software: you can redistribute it
+and/or modify it under the terms of the GNU General
+Public License as published by the Free Software
+Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General
+Public License along with this program. If not, see
+.
+
+*/
+
+using Gtk;
+using Poppler;
+
+int
+main (string[] argv)
+{
+
+ GLib.File gfile = null;
+ string doc_name = "";
+ int rotate = 0;
+ int index = 0;
+ int n_pages = 0;
+ bool invert = false;
+ bool grayscale = false;
+ double scale = 1.0;
+ double pgw = 0.0;
+ double pgh = 0.0;
+
+ Gtk.Application application =
+ new Gtk.Application (
+ "org.ramanpdf.www",
+ GLib.ApplicationFlags.HANDLES_OPEN);
+
+ // register with OSX to open file from Finder
+ // must be done here and
+ // cannot be done under startup
+ Value val = Value (GLib.Type.BOOLEAN);
+ val.set_boolean (true);
+ application.set_property ("register-session", val);
+ val.unset ();
+
+ application.startup.connect (()=>{
+
+ // application accelerator action
+ GLib.SimpleAction action1 =
+ new GLib.SimpleAction ("actiona", null);
+ action1.activate.connect (()=>{
+ //print("Action1\n");
+ application.quit();});
+ action1.set_enabled (true);
+ application.add_action (action1);
+ const string[] key1 = {"q"};
+ application.set_accels_for_action ("app.actiona", key1);
+
+ });
+
+ application.activate.connect (()=>{
+
+ // does not open any window
+ // but passes this to application.open
+ if (argv.length > 1)
+ {
+ GLib.File file =
+ GLib.File.new_for_commandline_arg (argv[1]);
+ application.open ({file},"");
+ return;
+ }
+ else {
+ application.open ({null},"");
+ return;
+ };
+
+ });
+
+ application.open.connect ((files, hint)=>{
+
+ // opens the window
+ gfile = files[0];
+
+ Gtk.ApplicationWindow window = null;
+ if (application.get_active_window () != null)
+ {
+ window = application.get_active_window () as
+ Gtk.ApplicationWindow;
+ }
+ else {
+ window = new Gtk.ApplicationWindow (application);
+ window.set_default_size (480, 360);
+ };
+
+ Gtk.ScrolledWindow screen =
+ new Gtk.ScrolledWindow ();
+ window.set_child (screen);
+
+ Gtk.DrawingArea da =
+ new Gtk.DrawingArea ();
+ screen.set_child (da);
+
+ da.set_draw_func ((da,cr,w,h)=>{
+
+ if (gfile == null)
+ {
+ cr.set_source_rgb (0.7,0.7,0.7);
+ cr.rectangle (0,0,w,h);
+ cr.fill ();
+ }
+ else
+ {
+
+ try
+ {
+ Poppler.Document popdoc =
+ new Poppler.Document.from_gfile (gfile,
+ null, null);
+
+ if (popdoc != null)
+ {
+
+ // whether run from commandline or from inside app
+ // window title is set here
+ doc_name = gfile.get_basename ();
+ window.set_title (doc_name);
+
+ n_pages = popdoc.get_n_pages ();
+ index %= n_pages;
+
+ Poppler.Page poppage =
+ popdoc.get_page (index);
+ poppage.get_size (out pgw, out pgh);
+
+ if ((rotate % 2) ==0)
+ {
+ da.set_content_width ((int)(pgw * scale));
+ da.set_content_height((int)(pgh * scale));
+ }
+ else
+ {
+ da.set_content_height((int)(pgw * scale));
+ da.set_content_width ((int)(pgh * scale));
+ };
+
+ Cairo.ImageSurface surface =
+ new Cairo.ImageSurface (
+ Cairo.Format.ARGB32,
+ (int)(scale * pgw),
+ (int)(scale * pgh));
+ Cairo.Context context =
+ new Cairo.Context (surface);
+ context.scale (scale,scale);
+ poppage.render (context);
+ switch (rotate) {
+ case 1:
+ cr.translate (
+ (double)(scale*pgh),
+ (double)(scale*0));
+ cr.rotate ((double)( 90*GLib.Math.PI/180));
+ break;
+ case 2:
+ cr.translate (
+ (double)(scale*pgw),
+ (double)(scale*pgh));
+ cr.rotate ((double)(180*GLib.Math.PI/180));
+ break;
+ case 3:
+ cr.translate (
+ (double)(scale*0),
+ (double)(scale*pgw));
+ cr.rotate ((double)(270*GLib.Math.PI/180));
+ break;
+ default:
+ break;
+ };
+ // lays an opaque white background
+ // because some PDF has transparent parts
+ cr.set_operator (Cairo.Operator.SOURCE);
+ cr.set_source_rgba (1,1,1,1);
+ cr.paint ();
+ // lays the PDF over the background
+ cr.set_operator (Cairo.Operator.OVER);
+ cr.set_source_surface (context.get_target (), 0, 0);
+ cr.paint ();
+ if (invert==true)
+ {
+ cr.set_operator (Cairo.Operator.DIFFERENCE);
+ cr.set_source_rgba (1,1,1,1);
+ cr.paint ();
+ };
+ if (grayscale==true)
+ {
+ cr.set_operator (Cairo.Operator.HSL_SATURATION);
+ cr.set_source_rgba(0,0,0,1);
+ cr.paint ();
+ };
+/*
+ print("%d of %d pages\n", index+1, n_pages);
+ print("Cairo scale: %f\n", scale);
+ print("Cairo rotate: %d\n", rotate);
+ print("Poppler page width: %d, height: %d\n",
+ (int)pgw, (int)pgh);
+ print("DA Content width: %d, height: %d\n",
+ da.get_content_width (),
+ da.get_content_height ());
+ print("Widget width: %d, height: %d\n",
+ screen.get_width(),
+ screen.get_height());
+ print("R:%1.1f G:%1.1f B:%1.1f A:%1.1f\n",
+ red, green, blue, alpha);
+*/
+
+ };
+
+ }
+ catch (GLib.Error e)
+ {
+ //print("Poppler: %s\n", e.message);
+ gfile = null; // stop repeating same error
+ doc_name = "";
+ window.set_title (e.message);
+ };
+ };
+ });
+
+ Gtk.EventControllerKey eventkey =
+ new Gtk.EventControllerKey ();
+ eventkey.key_pressed.connect ((keyval, keycode, state)=>{
+ //print ("keyval: %3u keycode: %3u\n", keyval, keycode);
+ //print ("keyval_name: %s\n", Gdk.keyval_name(keyval));
+ switch (Gdk.keyval_name (keyval)){
+ case "o":
+ FileDialog fileDialog =
+ new FileDialog ();
+ Cancellable cancellable = null;
+ fileDialog.set_accept_label ("open");
+ fileDialog.open.begin (window, cancellable,
+ (obj,res)=>{
+ try
+ {
+ gfile = fileDialog.open.end (res);
+ if (gfile != null)
+ {
+ //print ("File: %s\n", gfile.get_path ());
+ da.queue_draw (); // window title is set there
+ };
+ }
+ catch (GLib.Error e)
+ {
+ //print ("Open error: %s\n", e.message);
+ string error_message = e.message;
+ window.set_title (error_message);
+ }
+ });
+ break;
+ case "equal":
+ scale += 0.1;
+ da.queue_draw ();
+ break;
+ case "minus":
+ scale -= 0.1;
+ if (scale < 0.1) {scale = 0.1;};
+ da.queue_draw ();
+ break;
+ case "0":
+ scale = 1.0;
+ da.queue_draw ();
+ break;
+ case "space":
+ if ((gfile != null) && (n_pages != 0))
+ {
+ index++;
+ index %= n_pages;
+ da.queue_draw ();
+ }
+ break;
+ case "i":
+ invert = !invert;
+ da.queue_draw ();
+ break;
+ case "t":
+ rotate++;
+ rotate %= 4;
+ da.queue_draw ();
+ break;
+ case "d":
+ grayscale = !grayscale;
+ da.queue_draw ();
+ break;
+ default:
+ break;
+
+ };
+ return true;
+ });
+ screen.add_controller (eventkey);
+
+ window.present ();
+
+ });
+
+ var status = application.run (argv);
+ return status;
+}