Edit Book: Shortcut change of current paragraph to heading

Edit Book: Add a tool to easily change the current paragraph (the
paragraph containing the cursor) to a heading. Simply click the button
with 'H1' on it and choose the heading level you want the current
paragraph changed to.

src/calibre/gui2/tweak_book/editor/smart/html.py

@@ -6,13 +6,16 @@ from __future__ import (unicode_literals, division, absolute_import,
 __license__ = 'GPL v3'
 __copyright__ = '2014, Kovid Goyal <kovid at kovidgoyal.net>'
 
-import sys
+import sys, re
 from operator import itemgetter
 from . import NullSmarts
 
 from PyQt4.Qt import QTextEdit
 
+from calibre.gui2 import error_dialog
+
 get_offset = itemgetter(0)
+PARAGRAPH_SEPARATOR = '\u2029'
 
 class Tag(object):
 
@@ -104,6 +107,27 @@ def find_closing_tag(tag, max_tags=sys.maxint):
         max_tags -= 1
     return None
 
+def select_tag(cursor, tag):
+    cursor.setPosition(tag.start_block.position() + tag.start_offset)
+    cursor.setPosition(tag.end_block.position() + tag.end_offset + 1, cursor.KeepAnchor)
+    return unicode(cursor.selectedText()).replace(PARAGRAPH_SEPARATOR, '\n')
+
+def rename_tag(cursor, opening_tag, closing_tag, new_name, insert=False):
+    cursor.beginEditBlock()
+    text = select_tag(cursor, closing_tag)
+    if insert:
+        text = '</%s>%s' % (new_name, text)
+    else:
+        text = re.sub(r'^<\s*/\s*[a-zA-Z0-9]+', '</%s' % new_name, text)
+    cursor.insertText(text)
+    text = select_tag(cursor, opening_tag)
+    if insert:
+        text += '<%s>' % new_name
+    else:
+        text = re.sub(r'^<\s*[a-zA-Z0-9]+', '<%s' % new_name, text)
+    cursor.insertText(text)
+    cursor.endEditBlock()
+
 class HTMLSmarts(NullSmarts):
 
     def get_extra_selections(self, editor):
@@ -126,3 +150,34 @@ class HTMLSmarts(NullSmarts):
                 add_tag(tag)
         return ans
 
+    def rename_block_tag(self, editor, new_name):
+        c = editor.textCursor()
+        block, offset = c.block(), c.positionInBlock()
+        tag = None
+
+        while True:
+            tag = find_closest_containing_tag(block, offset)
+            if tag is None:
+                break
+            block, offset = tag.start_block, tag.start_offset
+            if tag.name in {
+                    'address', 'article', 'aside', 'blockquote', 'center',
+                    'dir', 'fieldset', 'isindex', 'menu', 'noframes', 'hgroup',
+                    'noscript', 'pre', 'section', 'h1', 'h2', 'h3', 'h4', 'h5',
+                    'h6', 'header', 'p', 'div', 'dd', 'dl', 'ul', 'ol', 'li', 'body',
+                    'td', 'th'}:
+                break
+            tag = None
+
+        if tag is not None:
+            closing_tag = find_closing_tag(tag)
+            if closing_tag is None:
+                return error_dialog(editor, _('Invalid HTML'), _(
+                    'There is an unclosed %s tag. You should run the Fix HTML tool'
+                    ' before trying to rename tags.') % tag.name, show=True)
+            rename_tag(c, tag, closing_tag, new_name, insert=tag.name in {'body', 'td', 'th', 'li'})
+        else:
+            return error_dialog(editor, _('No found'), _(
+                'No suitable block level tag was found to rename'), show=True)
+
+

src/calibre/gui2/tweak_book/editor/text.py

@@ -612,3 +612,7 @@ class TextEdit(PlainTextEdit):
         c.movePosition(c.End, c.KeepAnchor)
         self.setTextCursor(c)
 
+    def rename_block_tag(self, new_name):
+        if hasattr(self.smarts, 'rename_block_tag'):
+            self.smarts.rename_block_tag(self, new_name)
+

src/calibre/gui2/tweak_book/editor/widget.py

@@ -8,13 +8,30 @@ __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 
 import unicodedata
 
-from PyQt4.Qt import QMainWindow, Qt, QApplication, pyqtSignal, QMenu
+from PyQt4.Qt import (
+    QMainWindow, Qt, QApplication, pyqtSignal, QMenu, qDrawShadeRect, QPainter,
+    QImage, QColor, QIcon, QPixmap, QToolButton)
 
 from calibre.gui2 import error_dialog
 from calibre.gui2.tweak_book import actions, current_container
 from calibre.gui2.tweak_book.editor.text import TextEdit
 
-def register_text_editor_actions(reg):
+def create_icon(text, palette=None, sz=32, divider=2):
+    if palette is None:
+        palette = QApplication.palette()
+    img = QImage(sz, sz, QImage.Format_ARGB32)
+    img.fill(Qt.transparent)
+    p = QPainter(img)
+    p.setRenderHints(p.TextAntialiasing | p.Antialiasing)
+    qDrawShadeRect(p, img.rect(), palette, fill=QColor('#ffffff'), lineWidth=1, midLineWidth=1)
+    f = p.font()
+    f.setFamily('Liberation Sans'), f.setPixelSize(sz // divider), f.setBold(True)
+    p.setFont(f), p.setPen(Qt.black)
+    p.drawText(img.rect().adjusted(2, 2, -2, -2), Qt.AlignCenter, text)
+    p.end()
+    return QIcon(QPixmap.fromImage(img))
+
+def register_text_editor_actions(reg, palette):
     ac = reg('format-text-bold', _('&Bold'), ('format_text', 'bold'), 'format-text-bold', 'Ctrl+B', _('Make the selected text bold'))
     ac.setToolTip(_('<h3>Bold</h3>Make the selected text bold'))
     ac = reg('format-text-italic', _('&Italic'), ('format_text', 'italic'), 'format-text-italic', 'Ctrl+I', _('Make the selected text italic'))
@@ -39,6 +56,12 @@ def register_text_editor_actions(reg):
     ac = reg('view-image', _('&Insert image'), ('insert_resource', 'image'), 'insert-image', (), _('Insert an image into the text'))
     ac.setToolTip(_('<h3>Insert image</h3>Insert an image into the text'))
 
+    for i, name in enumerate(('h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'p')):
+        text = ('&' + name) if name == 'p' else (name[0] + '&' + name[1])
+        desc = _('Convert the paragraph to &lt;%s&gt;') % name
+        ac = reg(create_icon(name), text, ('rename_block_tag', name), 'rename-block-tag-' + name, 'Ctrl+%d' % (i + 1), desc)
+        ac.setToolTip(desc)
+
 class Editor(QMainWindow):
 
     has_line_numbers = True
@@ -176,6 +199,12 @@ class Editor(QMainWindow):
             self.format_bar = b = self.addToolBar(_('Format text'))
             for x in ('bold', 'italic', 'underline', 'strikethrough', 'subscript', 'superscript', 'color', 'background-color'):
                 b.addAction(actions['format-text-%s' % x])
+            ac = b.addAction(QIcon(I('format-text-heading.png')), _('Change paragraph to heading'))
+            m = QMenu()
+            ac.setMenu(m)
+            b.widgetForAction(ac).setPopupMode(QToolButton.InstantPopup)
+            for name in tuple('h%d' % d for d in range(1, 7)) + ('p',):
+                m.addAction(actions['rename-block-tag-%s' % name])
 
     def break_cycles(self):
         self.modification_state_changed.disconnect()

src/calibre/gui2/tweak_book/ui.py

@@ -270,7 +270,9 @@ class Main(MainWindow):
         group = _('Global Actions')
 
         def reg(icon, text, target, sid, keys, description):
-            ac = actions[sid] = QAction(QIcon(I(icon)), text, self) if icon else QAction(text, self)
+            if not isinstance(icon, QIcon):
+                icon = QIcon(I(icon))
+            ac = actions[sid] = QAction(icon, text, self) if icon else QAction(text, self)
             ac.setObjectName('action-' + sid)
             if target is not None:
                 ac.triggered.connect(target)
@@ -315,7 +317,7 @@ class Main(MainWindow):
 
         def ereg(icon, text, target, sid, keys, description):
             return reg(icon, text, partial(self.boss.editor_action, target), sid, keys, description)
-        register_text_editor_actions(ereg)
+        register_text_editor_actions(ereg, self.palette())
 
         # Tool actions
         group = _('Tools')