[gnome-documents/wip/epub-colors: 1/3] epubview: font size and invert colors buttons

[Cosimo Cecchi <cosimoc src gnome org>]

commit 4ea361e30fc0b7fab6ac4140661980fb0880ff46
Author: Daniel Garcia Moreno <danigm wadobo com>
Date:   Thu Jun 30 10:19:52 2016 +0200

    epubview: font size and invert colors buttons
    
    I've added a new menu to control font options. In this menu I've added the
    font size buttons and another button to invert colors.
    
    The invert colors assume that the background is light and the text is dark
    and when it's inverted sets the background to black and the text to white.
    
    The menu is ugly now, if we can create some buttons or widgets in this
    menu, it will look a lot better.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=768004

 src/epubview.js |  100 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 98 insertions(+), 2 deletions(-)
---
diff --git a/src/epubview.js b/src/epubview.js
index 2a637a7..70d8120 100644
--- a/src/epubview.js
+++ b/src/epubview.js
@@ -22,6 +22,7 @@
 const GdPrivate = imports.gi.GdPrivate;
 const Gepub = imports.gi.Gepub;
 const Gio = imports.gi.Gio;
+const Gtk = imports.gi.Gtk;
 const WebKit2 = imports.gi.WebKit2;
 
 const _ = imports.gettext.gettext;
@@ -39,6 +40,12 @@ const EPUBView = new Lang.Class({
     Name: 'EPUBView',
     Extends: Preview.Preview,
 
+    _init: function(preview) {
+        this.invertedColors = false;
+
+        this.parent(preview);
+    },
+
     createActions: function() {
         return [
             { name: 'find-prev',
@@ -47,6 +54,22 @@ const EPUBView = new Lang.Class({
             { name: 'find-next',
               callback: Lang.bind(this, this.findNext),
               accels: ['<Primary>g'] },
+            { name: 'font-increase',
+              callback: Lang.bind(this, function() {
+                this.increaseFontSize();
+              }) },
+            { name: 'font-decrease',
+              callback: Lang.bind(this, function() {
+                this.decreaseFontSize();
+              }) },
+            { name: 'font-normal',
+              callback: Lang.bind(this, function() {
+                this.defaultFontSize();
+              }) },
+            { name: 'font-invert-colors',
+              callback: Lang.bind(this, function() {
+                this.invertColors();
+              }) }
         ];
     },
 
@@ -55,7 +78,17 @@ const EPUBView = new Lang.Class({
     },
 
     createView: function() {
-        return new Gepub.Widget();
+        let view = new Gepub.Widget();
+        let settings = view.get_settings();
+        settings.set_zoom_text_only(true);
+
+        view.connect('load-changed', Lang.bind(this, function(wview, ev, data) {
+            if (ev == WebKit2.LoadEvent.FINISHED) {
+               this.setInvertedColors();
+            }
+        }));
+
+        return view;
     },
 
     createContextMenu: function() {
@@ -78,6 +111,11 @@ const EPUBView = new Lang.Class({
         this._metadata = this._loadMetadata();
 
         this.set_visible_child_name('view');
+
+        this.getAction('font-increase').enabled = true;
+        this.getAction('font-decrease').enabled = true;
+        this.getAction('font-normal').enabled = true;
+        this.getAction('font-invert-colors').enabled = true;
     },
 
     _loadMetadata: function() {
@@ -106,6 +144,7 @@ const EPUBView = new Lang.Class({
 
     goNext: function() {
         this._epubdoc.go_next();
+
     },
 
     get hasPages() {
@@ -139,7 +178,38 @@ const EPUBView = new Lang.Class({
     findPrev: function() {
         let fc = this.view.get_find_controller();
         fc.search_previous();
-    }
+    },
+
+    increaseFontSize: function() {
+        var zoom = this.view.get_zoom_level();
+        this.view.set_zoom_level(zoom + 0.2);
+    },
+
+    decreaseFontSize: function() {
+        var zoom = this.view.get_zoom_level();
+        this.view.set_zoom_level(zoom - 0.2);
+    },
+
+    defaultFontSize: function() {
+        this.view.set_zoom_level(1);
+    },
+
+    setInvertedColors: function() {
+        let script;
+        if (this.invertedColors) {
+            script = "document.querySelector('body').style.backgroundColor = 'black';";
+            script += "document.querySelector('body').style.color = 'white';";
+        } else {
+            script = "document.querySelector('body').style.backgroundColor = '';";
+            script += "document.querySelector('body').style.color = '';";
+        }
+        this.view.run_javascript(script, null, null);
+    },
+
+    invertColors: function(change) {
+        this.invertedColors = !this.invertedColors;
+        this.setInvertedColors();
+    },
 });
 
 const EPUBSearchbar = new Lang.Class({
@@ -174,6 +244,32 @@ const EPUBViewToolbar = new Lang.Class({
     Name: 'EPUBViewToolbar',
     Extends: Preview.PreviewToolbar,
 
+    _init: function(preview) {
+        this.parent(preview);
+
+        let fontButton = new Gtk.MenuButton({ image: new Gtk.Image ({ icon_name: 'font-select-symbolic' }),
+                                              menu_model: this._getFontMenu(),
+                                              action_name: 'view.font-menu' });
+        fontButton.set_sensitive(true);
+        this.toolbar.pack_end(fontButton);
+        this.toolbar.show_all();
+    },
+
+    _getFontMenu: function() {
+        let new_action;
+        let menuItem;
+        let menu = new Gio.Menu();
+        let application = Gio.Application.get_default();
+
+        menu.append(_('increase font size'), 'view.font-increase');
+        menu.append(_('decrease font size'), 'view.font-decrease');
+        menu.append(_('default font size'), 'view.font-normal');
+
+        menu.append(_('invert colors'), 'view.font-invert-colors');
+
+        return menu;
+    },
+
     createSearchbar: function() {
         return new EPUBSearchbar(this.preview);
     }