From 99f86498c0bbdf18fb1c3fa4f8ab4d9694473c5b Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sun, 14 Mar 2021 19:15:22 +0530
Subject: [PATCH] E-book viewer: Make the commonly used shift+arrow key
 shortcuts for modifying selections using the keyboard work

Fixes #1919072 [[Enhancement - Viewer] Change which text is selected using Shift+arrow keys](https://bugs.launchpad.net/calibre/+bug/1919072)
---
 src/pyj/read_book/selection_bar.pyj | 12 +++++++++++-
 src/pyj/read_book/shortcuts.pyj     | 12 ++++++++++++
 src/pyj/read_book/view.pyj          |  4 ++++
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/src/pyj/read_book/selection_bar.pyj b/src/pyj/read_book/selection_bar.pyj
index b01b6ab5e3..d154bb1596 100644
--- a/src/pyj/read_book/selection_bar.pyj
+++ b/src/pyj/read_book/selection_bar.pyj
@@ -573,9 +573,19 @@ class SelectionBar:
             self.copy_to_clipboard()
             return
         sc_name = shortcut_for_key_event(ev, self.view.keyboard_shortcut_map)
+        if ev.key is 'ArrowRight' and ev.shiftKey:
+            sc_name = 'extend_selection_by_word'
+        elif ev.key is 'ArrowLeft' and ev.shiftKey:
+            sc_name = 'shrink_selection_by_word'
+
         if not sc_name:
             return
-        forwarded = {'toggle_highlights': True, 'extend_selection_by_word': True, 'shrink_selection_by_word': True, 'edit_book': True}
+        forwarded = {
+            'toggle_highlights': True,
+            'edit_book': True,
+            'extend_selection_by_word': True, 'shrink_selection_by_word': True,
+            'extend_selection_by_line': True, 'shrink_selection_by_line': True,
+        }
         if sc_name is 'show_chrome':
             self.clear_selection()
         elif sc_name is 'copy_to_clipboard':
diff --git a/src/pyj/read_book/shortcuts.pyj b/src/pyj/read_book/shortcuts.pyj
index cb168fddd5..ee5e2186a5 100644
--- a/src/pyj/read_book/shortcuts.pyj
+++ b/src/pyj/read_book/shortcuts.pyj
@@ -326,6 +326,18 @@ def common_shortcuts():  # {{{
         _('Alter the current selection backwards by a word'),
     ),
 
+    'extend_selection_by_line': desc(
+        v"['Ctrl+Shift+ArrowDown', 'Shift+ArrowDown']",
+        'ui',
+        _('Alter the current selection forward by a line'),
+    ),
+
+    'shrink_selection_by_line': desc(
+        v"['Ctrl+Shift+ArrowUp', 'Shift+ArrowUp']",
+        'ui',
+        _('Alter the current selection backwards by a line'),
+    ),
+
     'show_chrome': desc(
         v"['Escape', 'ContextMenu']",
         'ui',
diff --git a/src/pyj/read_book/view.pyj b/src/pyj/read_book/view.pyj
index 23fc617815..c444d87cba 100644
--- a/src/pyj/read_book/view.pyj
+++ b/src/pyj/read_book/view.pyj
@@ -563,6 +563,10 @@ class View:
             self.iframe_wrapper.send_message('modify_selection', direction='backward', granularity='word')
         elif data.name is 'extend_selection_by_word':
             self.iframe_wrapper.send_message('modify_selection', direction='forward', granularity='word')
+        elif data.name is 'shrink_selection_by_line':
+            self.iframe_wrapper.send_message('modify_selection', direction='backward', granularity='line')
+        elif data.name is 'extend_selection_by_line':
+            self.iframe_wrapper.send_message('modify_selection', direction='forward', granularity='line')
         elif data.name is 'scrollspeed_increase':
             self.update_scroll_speed(SCROLL_SPEED_STEP)
         elif data.name is 'scrollspeed_decrease':