Color scheme support for the viewer

src/pyj/read_book/globals.pyj

@@ -4,6 +4,7 @@ from __python__ import hash_literals
 
 from aes import GCM, random_bytes
 from encodings import hexlify
+from gettext import gettext as _, register_callback, gettext as gt
 
 _boss = None
 
@@ -49,3 +50,18 @@ def current_spine_item():
 def set_current_spine_item(val):
     nonlocal _current_spine_item
     _current_spine_item = val
+
+
+default_color_schemes = {
+    'white':{'foreground':'black', 'background':'white', 'name':_('White')},
+    'black':{'foreground':'white', 'background':'black', 'name':_('Black')},
+    'sepia-light':{'foreground':'#643b0f', 'background':'#2a2c05', 'name':_('Sepia Light')},
+    'sepia-dark':{'background':'#643b0f', 'foreground':'#2a2c05', 'name':_('Sepia Dark')},
+}
+
+register_callback(def():
+    # Ensure the color scheme names are translated
+    for key in default_color_schemes:
+        scheme = default_color_schemes[key]
+        scheme.name = gt(scheme.name)
+)

src/pyj/read_book/iframe.pyj

@@ -4,6 +4,7 @@ from __python__ import bound_methods, hash_literals
 
 import traceback
 from aes import GCM
+from elementmaker import E
 from gettext import install, gettext as _
 from read_book.cfi import at_current, scroll_to as scroll_to_cfi
 from read_book.globals import set_boss, set_current_spine_item, current_layout_mode, current_spine_item, set_layout_mode
@@ -19,7 +20,7 @@ from read_book.paged_mode import (
     jump_to_cfi as paged_jump_to_cfi, handle_gesture as paged_handle_gesture,
     scroll_by_page as paged_scroll_by_page
 )
-from read_book.settings import apply_settings
+from read_book.settings import apply_settings, opts
 from read_book.touch import create_handlers as create_touch_handlers
 from utils import debounce
 
@@ -75,6 +76,7 @@ class IframeBoss:
             install(data.translations)
         window.onerror = self.onerror
         create_touch_handlers()
+        self.color_scheme = data.color_scheme
 
     def onerror(self, msg, script_url, line_number, column_number, error_object):
         console.log(error_object)
@@ -135,6 +137,9 @@ class IframeBoss:
 
     def content_loaded(self):
         document.documentElement.style.overflow = 'hidden'
+        document.body.appendChild(
+            E.style(str.format('html, body {{ color: {} !important; background-color: {} !important }}', opts.color_scheme.foreground, opts.color_scheme.background))
+        )
         self.do_layout()
         if self.mathjax:
             return apply_mathjax(self.mathjax, self.book.manifest.link_uid, self.content_loaded_stage2)

src/pyj/read_book/overlay.pyj

@@ -168,7 +168,7 @@ class MainOverlay:
         add_button('search', _('Search for text in this book'))
         add_button()
         add_button('Aa', _('Change text size'), text_button=True)
-        add_button('cogs', _('Configure the book reader'))
+        add_button('cogs', _('Configure the book reader'), self.overlay.show_prefs)
         add_button()
 
     def update_time(self):
@@ -209,6 +209,20 @@ class TOCOverlay: # {{{
         self.overlay.view.goto_named_destination(dest, frag)
 # }}}
 
+class PrefsOverlay: # {{{
+
+    def __init__(self, overlay):
+        self.overlay = overlay
+
+    def on_container_click(self, evt):
+        pass  # Dont allow panel to be closed by a click
+
+    def show(self, container):
+        container.style.backgroundColor = get_color('window-background')
+        create_prefs_panel(container, self.overlay.hide_current_panel)
+
+# }}}
+
 class Overlay:
 
     def __init__(self, view):
@@ -281,3 +295,7 @@ class Overlay:
     def show_toc(self):
         self.panels.push(TOCOverlay(self))
         self.show_current_panel()
+
+    def show_prefs(self):
+        self.panels.push(PrefsOverlay(self))
+        self.show_current_panel()

src/pyj/read_book/settings.pyj

@@ -9,5 +9,6 @@ def apply_settings(settings):
     opts.cols_per_screen = max(1, settings.cols_per_screen or 1)
     opts.margin_left = max(0, settings.margin_left or 0)
     opts.margin_right = max(0, settings.margin_right or 0)
+    opts.color_scheme = settings.color_scheme
 
 apply_settings()

src/pyj/read_book/view.pyj

@@ -6,7 +6,7 @@ from book_list.globals import get_session_data, get_boss
 from dom import set_css, add_extra_css, build_rule, svgicon
 from elementmaker import E
 from gettext import gettext as _
-from read_book.globals import messenger, iframe_id
+from read_book.globals import messenger, iframe_id, default_color_schemes
 from read_book.resources import load_resources
 from read_book.overlay import Overlay
 from book_list.theme import get_color
@@ -34,7 +34,7 @@ __BS__
 add_extra_css(def():
     sel = '.book-side-margin'
     ans = build_rule(sel, cursor='pointer', color='rgba(0, 0, 0, 0)', text_align='center', height='100vh', user_select='none', display='flex', align_items='center', justify_content='center')
-    ans += build_rule(sel + ':hover', background_color=get_color('window-background'), color=get_color('window-foreground'))
+    ans += build_rule(sel + ':hover', background_color=get_color('window-background') + ' !important', color=get_color('window-foreground') + ' !important')
     ans += build_rule(sel + ':active > svg', color='red', transform='scale(2)')
     return ans
 )
@@ -176,6 +176,23 @@ class View:
     def on_iframe_error(self, data):
         self.ui.show_error((data.title or _('There was an error processing the book')), data.msg, data.details)
 
+    def get_color_scheme(self, apply_to_margins):
+        sd = get_session_data()
+        cs = sd.current_color_scheme or 'white'
+        if default_color_schemes[cs]:
+            ans = default_color_schemes[cs]
+        elif sd.user_color_schemes[cs] and sd.user_color_schemes[cs].foreground and sd.user_color_schemes[cs].background:
+            ans = sd.user_color_schemes[cs]
+        else:
+            ans = default_color_schemes['white']
+        if apply_to_margins:
+            for which in 'left top right bottom'.split(' '):
+                s = document.getElementById('book-{}-margin'.format(which)).style
+                if which is 'top' or which is 'bottom':
+                    s.color = ans.foreground  # Setting a color for the side margins causes the hover arrow to become visible
+                s.backgroundColor = ans.background
+        return ans
+
     def on_resize(self):
         pass
 
@@ -222,6 +239,7 @@ class View:
             'margin_right': 0 if name is self.book.manifest.title_page_name else sd.get('margin_right'),
             'read_mode': sd.get('read_mode'),
             'cols_per_screen': sd.get('cols_per_screen'),
+            'color_scheme': self.get_color_scheme(True),
         }
         initial_position = initial_position or {'replace_history':False}
         self.currently_showing = {'name':name, 'settings':settings, 'initial_position':initial_position, 'loading':True}

src/pyj/session.pyj

@@ -26,6 +26,20 @@ defaults = {
     'max_text_height': 0,
     'max_text_width': 0,
     'cols_per_screen': 1,
+    'current_color_scheme': 'white',
+    'user_color_schemes': {},
+}
+
+is_local_setting = {
+    'margin_right': True,
+    'margin_left': True,
+    'margin_top': True,
+    'margin_bottom': True,
+    'read_mode': 'paged',
+    'max_text_height': True,
+    'max_text_width': True,
+    'cols_per_screen': True,
+    'current_color_scheme': True,
 }
 
 def storage_available(which):
@@ -132,7 +146,8 @@ class UserSessionData(SessionData):
         self.push_timer_id = None
         if saved_data:
             for key in saved_data:
-                self.set(key, saved_data[key])
+                if not is_local_setting[key]:
+                    self.set(key, saved_data[key])
         self.echo_changes = True
 
     def defval(self, key):
@@ -152,7 +167,7 @@ class UserSessionData(SessionData):
         return self.get(lkey, defval)
 
     def set(self, key, value):
-        if self.echo_changes and self.has_user:
+        if self.echo_changes and self.has_user and not is_local_setting[key]:
             self.changes[key] = value
             self.has_changes = True
             if self.push_timer_id is not None: