Viewer: Much improved search functionality. Now all matches are displayed with a few surrounding words. Also supports using regular expressions to search. Fixes #1834247 [Enhanced Search [Enhancement]](https://bugs.launchpad.net/calibre/+bug/1834247)

src/calibre/gui2/viewer/search.py

@@ -17,6 +17,7 @@ from PyQt5.Qt import (
 )
 
 from calibre.ebooks.conversion.search_replace import REGEX_FLAGS
+from calibre.gui2 import warning_dialog
 from calibre.gui2.progress_indicator import ProgressIndicator
 from calibre.gui2.viewer.web_view import get_data, get_manifest, vprefs
 from calibre.gui2.widgets2 import HistoryComboBox
@@ -36,14 +37,17 @@ class BusySpinner(QWidget):  # {{{
         self.la = la = QLabel(_('Searching...'))
         l.addWidget(la)
         l.addStretch(10)
+        self.is_running = False
 
     def start(self):
         self.setVisible(True)
         self.pi.start()
+        self.is_running = True
 
     def stop(self):
         self.setVisible(False)
         self.pi.stop()
+        self.is_running = False
 # }}}
 
 
@@ -92,7 +96,11 @@ class SearchResult(object):
     def static_text(self):
         if self._static_text is None:
             before_words = self.before.split()
-            before = '…' + ' '.join(before_words[-3:])[:15]
+            before = ' '.join(before_words[-3:])
+            before_extra = len(before) - 15
+            if before_extra > 0:
+                before = before[before_extra:]
+            before = '…' + before
             before_space = '' if self.before.rstrip() == self.before else ' '
             after_words = self.after.split()
             after = ' '.join(after_words[:3])[:15] + '…'
@@ -102,6 +110,13 @@ class SearchResult(object):
             st.setTextWidth(10000)
         return self._static_text
 
+    @property
+    def for_js(self):
+        return {'file_name': self.file_name, 'spine_idx': self.spine_idx, 'index': self.index, 'text': self.text}
+
+    def is_or_is_after(self, result_from_js):
+        return result_from_js['spine_idx'] == self.spine_idx and self.index >= result_from_js['index'] and result_from_js['text'] == self.text
+
 
 @lru_cache(maxsize=None)
 def searchable_text_for_name(name):
@@ -198,7 +213,7 @@ class SearchInput(QWidget):  # {{{
         qt.setCurrentIndex(qt.findData(vprefs.get('viewer-search-mode', 'normal') or 'normal'))
         h.addWidget(qt)
 
-        self.case_sensitive = cs = QCheckBox(_('Case sensitive'), self)
+        self.case_sensitive = cs = QCheckBox(_('&Case sensitive'), self)
         cs.setFocusPolicy(Qt.NoFocus)
         cs.setChecked(bool(vprefs.get('viewer-search-case-sensitive', False)))
         h.addWidget(cs)
@@ -304,6 +319,28 @@ class Results(QListWidget):  # {{{
         i %= self.count()
         self.setCurrentRow(i)
         self.item_activated()
+
+    def search_result_not_found(self, sr):
+        remove = []
+        for i in range(self.count()):
+            item = self.item(i)
+            r = item.data(Qt.UserRole)
+            if r.is_or_is_after(sr):
+                remove.append(i)
+        if remove:
+            last_i = remove[-1]
+            if last_i < self.count() - 1:
+                self.setCurrentRow(last_i + 1)
+                self.item_activated()
+            elif remove[0] > 0:
+                self.setCurrentRow(remove[0] - 1)
+                self.item_activated()
+            for i in reversed(remove):
+                self.takeItem(i)
+            if self.count():
+                warning_dialog(self, _('Hidden text'), _(
+                    'Some search results were for hidden text, they have been removed.'), show=True)
+
 # }}}
 
 
@@ -311,6 +348,7 @@ class SearchPanel(QWidget):  # {{{
 
     search_requested = pyqtSignal(object)
     results_found = pyqtSignal(object)
+    show_search_result = pyqtSignal(object)
 
     def __init__(self, parent=None):
         QWidget.__init__(self, parent)
@@ -323,6 +361,7 @@ class SearchPanel(QWidget):  # {{{
         si.do_search.connect(self.search_requested)
         l.addWidget(si)
         self.results = r = Results(self)
+        r.show_search_result.connect(self.do_show_search_result, type=Qt.QueuedConnection)
         l.addWidget(r, 100)
         self.spinner = s = BusySpinner(self)
         s.setVisible(False)
@@ -362,15 +401,14 @@ class SearchPanel(QWidget):  # {{{
             if spine_idx < 0:
                 self.results_found.emit(SearchFinished(search_query))
                 continue
-            names = spine[spine_idx:] + spine[:spine_idx]
+            for name in spine:
-            for name in names:
                 counter = Counter()
                 spine_idx = idx_map[name]
                 try:
                     for i, result in enumerate(search_in_name(name, search_query)):
                         before, text, after = result
-                        counter[text] += 1
                         self.results_found.emit(SearchResult(search_query, before, text, after, name, spine_idx, counter[text]))
+                        counter[text] += 1
                 except Exception:
                     import traceback
                     traceback.print_exc()
@@ -381,6 +419,8 @@ class SearchPanel(QWidget):  # {{{
             return
         if isinstance(result, SearchFinished):
             self.spinner.stop()
+            if not self.results.count():
+                self.show_no_results_found()
             return
         if self.results.add_result(result) == 1:
             # first result
@@ -401,4 +441,17 @@ class SearchPanel(QWidget):  # {{{
 
     def find_next_requested(self, previous):
         self.results.find_next(previous)
+
+    def do_show_search_result(self, sr):
+        self.show_search_result.emit(sr.for_js)
+
+    def search_result_not_found(self, sr):
+        self.results.search_result_not_found(sr)
+        if not self.results.count() and not self.spinner.is_running:
+            self.show_no_results_found()
+
+    def show_no_results_found(self):
+        if self.current_search:
+            warning_dialog(self, _('No matches found'), _(
+                'No matches were found for: <b>{}</b>').format(self.current_search.text), show=True)
 # }}}

src/calibre/gui2/viewer/ui.py

@@ -159,6 +159,8 @@ class EbookViewer(MainWindow):
         self.web_view.toggle_toc.connect(self.toggle_toc)
         self.web_view.show_search.connect(self.show_search)
         self.web_view.find_next.connect(self.search_widget.find_next_requested)
+        self.search_widget.show_search_result.connect(self.web_view.show_search_result)
+        self.web_view.search_result_not_found.connect(self.search_widget.search_result_not_found)
         self.web_view.toggle_bookmarks.connect(self.toggle_bookmarks)
         self.web_view.toggle_inspector.connect(self.toggle_inspector)
         self.web_view.toggle_lookup.connect(self.toggle_lookup)

src/calibre/gui2/viewer/web_view.py

@@ -249,6 +249,7 @@ class ViewerBridge(Bridge):
     toggle_inspector = from_js()
     toggle_lookup = from_js()
     show_search = from_js()
+    search_result_not_found = from_js(object)
     find_next = from_js(object)
     quit = from_js()
     update_current_toc_nodes = from_js(object, object)
@@ -282,6 +283,7 @@ class ViewerBridge(Bridge):
     goto_frac = to_js()
     trigger_shortcut = to_js()
     set_system_palette = to_js()
+    show_search_result = to_js()
 
 
 def apply_font_settings(page_or_view):
@@ -419,6 +421,7 @@ class WebView(RestartingWebEngineView):
     reload_book = pyqtSignal()
     toggle_toc = pyqtSignal()
     show_search = pyqtSignal()
+    search_result_not_found = pyqtSignal(object)
     find_next = pyqtSignal(object)
     toggle_bookmarks = pyqtSignal()
     toggle_inspector = pyqtSignal()
@@ -464,6 +467,7 @@ class WebView(RestartingWebEngineView):
         self.bridge.reload_book.connect(self.reload_book)
         self.bridge.toggle_toc.connect(self.toggle_toc)
         self.bridge.show_search.connect(self.show_search)
+        self.bridge.search_result_not_found.connect(self.search_result_not_found)
         self.bridge.find_next.connect(self.find_next)
         self.bridge.toggle_bookmarks.connect(self.toggle_bookmarks)
         self.bridge.toggle_inspector.connect(self.toggle_inspector)
@@ -654,5 +658,8 @@ class WebView(RestartingWebEngineView):
     def trigger_shortcut(self, which):
         self.execute_when_ready('trigger_shortcut', which)
 
+    def show_search_result(self, sr):
+        self.execute_when_ready('show_search_result', sr)
+
     def palette_changed(self):
         self.execute_when_ready('set_system_palette', system_colors())

src/pyj/read_book/iframe.pyj

@@ -112,6 +112,7 @@ class IframeBoss:
             'wheel_from_margin': self.wheel_from_margin,
             'window_size': self.received_window_size,
             'overlay_visibility_changed': self.on_overlay_visibility_changed,
+            'show_search_result': self.show_search_result,
         }
         self.comm = IframeClient(handlers)
         self.last_window_ypos = 0
@@ -312,6 +313,8 @@ class IframeBoss:
                 self.scroll_to_ref(ipos.refnum)
             elif ipos.type is 'cfi':
                 self.jump_to_cfi(ipos.cfi)
+            elif ipos.type is 'search_result':
+                self.show_search_result(ipos, True)
             elif ipos.type is 'search':
                 self.find(ipos.search_data, True)
         spine = self.book.manifest.spine
@@ -526,6 +529,18 @@ class IframeBoss:
             else:
                 self.send_message('find_in_spine', text=data.text, backwards=data.backwards, searched_in_spine=data.searched_in_spine)
 
+    def show_search_result(self, data, from_load):
+        sr = data.search_result
+        idx = -1
+        window.getSelection().removeAllRanges()
+        while idx < sr.index:
+            if not window.find(sr.text, True, False, False, False, False):
+                self.send_message('search_result_not_found', search_result=sr)
+                break
+            idx += 1
+        if idx > -1 and current_layout_mode() is not 'flow':
+            snap_to_selection()
+
     def reference_item_changed(self, ref_num_or_none):
         self.send_message('reference_item_changed', refnum=ref_num_or_none, index=current_spine_item().index)
 

src/pyj/read_book/view.pyj

@@ -242,6 +242,9 @@ class View:
             'update_cfi': self.on_update_cfi,
             'update_progress_frac': self.on_update_progress_frac,
             'update_toc_position': self.on_update_toc_position,
+            'search_result_not_found': def (data): if ui_operations.search_result_not_found:
+                ui_operations.search_result_not_found(data.search_result)
+            ,
         }
         entry_point = None if runtime.is_standalone_viewer else 'read_book.iframe'
         if runtime.is_standalone_viewer:
@@ -1072,3 +1075,9 @@ class View:
         else:
             div.style.display = 'block'
             div.textContent = f'{index}.{refnum}'
+
+    def show_search_result(self, sr):
+        if self.currently_showing.name is sr.file_name:
+            self.iframe_wrapper.send_message('show_search_result', search_result=sr)
+        else:
+            self.show_name(sr.file_name, initial_position={'type':'search_result', 'search_result':sr, 'replace_history':True})

src/pyj/viewer-main.pyj

@@ -288,6 +288,12 @@ def trigger_shortcut(which):
         view.on_handle_shortcut({'name': which})
 
 
+@from_python
+def show_search_result(sr):
+    if view:
+        view.show_search_result(sr)
+
+
 def onerror(msg, script_url, line_number, column_number, error_object):
     if not error_object:
         # cross domain error
@@ -393,6 +399,8 @@ if window is window.top:
         to_python.customize_toolbar()
     ui_operations.autoscroll_state_changed = def(active):
         to_python.autoscroll_state_changed(active)
+    ui_operations.search_result_not_found = def(sr):
+        to_python.search_result_not_found(sr)
 
     document.body.appendChild(E.div(id='view'))
     window.onerror = onerror