Implement loading of resources direct from editrs->preview pane

src/calibre/gui2/tweak_book/__init__.py

@@ -24,3 +24,4 @@ def set_current_container(container):
     _current_container = container
 
 actions = {}
+editors = {}

src/calibre/gui2/tweak_book/boss.py

@@ -21,7 +21,7 @@ from calibre.ebooks.oeb.polish.container import get_container as _gc, clone_cont
 from calibre.ebooks.oeb.polish.replace import rename_files
 from calibre.gui2 import error_dialog, choose_files, question_dialog, info_dialog
 from calibre.gui2.dialogs.confirm_delete import confirm
-from calibre.gui2.tweak_book import set_current_container, current_container, tprefs, actions
+from calibre.gui2.tweak_book import set_current_container, current_container, tprefs, actions, editors
 from calibre.gui2.tweak_book.undo import GlobalUndoHistory
 from calibre.gui2.tweak_book.save import SaveManager
 from calibre.gui2.tweak_book.editor import editor_from_syntax, syntax_from_mime
@@ -40,7 +40,6 @@ class Boss(QObject):
         self.save_manager = SaveManager(parent)
         self.save_manager.report_error.connect(self.report_save_error)
         self.doing_terminal_save = False
-        self.editors = {}
 
     def __call__(self, gui):
         self.gui = gui
@@ -57,7 +56,7 @@ class Boss(QObject):
         return tempfile.mkdtemp(prefix='%s%05d-' % (prefix, self.container_count), dir=self.tdir)
 
     def check_dirtied(self):
-        dirtied = {name for name, ed in self.editors.iteritems() if ed.is_modified}
+        dirtied = {name for name, ed in editors.iteritems() if ed.is_modified}
         if not dirtied:
             return True
         return question_dialog(self.gui, _('Unsaved changes'), _(
@@ -124,7 +123,7 @@ class Boss(QObject):
         self.gui.action_save.setEnabled(True)
         self.gui.file_list.delete_done(spine_items, other_items)
         for name in list(spine_items) + list(other_items):
-            if name in self.editors:
+            if name in editors:
                 self.close_editor(name)
         # TODO: Update other GUI elements
 
@@ -210,7 +209,7 @@ class Boss(QObject):
 
     def save_book(self):
         c = current_container()
-        for name, ed in self.editors.iteritems():
+        for name, ed in editors.iteritems():
             if ed.is_modified:
                 with c.open(name, 'wb') as f:
                     f.write(ed.data)
@@ -229,9 +228,9 @@ class Boss(QObject):
                        ' for more information.'), det_msg=tb, show=True)
 
     def edit_file(self, name, syntax):
-        editor = self.editors.get(name, None)
+        editor = editors.get(name, None)
         if editor is None:
-            editor = self.editors[name] = editor_from_syntax(syntax, self.gui.editor_tabs)
+            editor = editors[name] = editor_from_syntax(syntax, self.gui.editor_tabs)
             editor.undo_redo_state_changed.connect(self.editor_undo_redo_state_changed)
             self.gui.central.add_editor(name, editor)
             c = current_container()
@@ -241,8 +240,8 @@ class Boss(QObject):
         self.gui.central.show_editor(editor)
 
     def edit_file_requested(self, name, syntax, mime):
-        if name in self.editors:
+        if name in editors:
-            self.gui.show_editor(self.editors[name])
+            self.gui.show_editor(editors[name])
             return
         syntax = syntax or syntax_from_mime(mime)
         if not syntax:
@@ -281,7 +280,7 @@ class Boss(QObject):
 
     def editor_close_requested(self, editor):
         name = None
-        for n, ed in self.editors.iteritems():
+        for n, ed in editors.iteritems():
             if ed is editor:
                 name = n
         if not name:
@@ -294,7 +293,7 @@ class Boss(QObject):
         self.close_editor(name)
 
     def close_editor(self, name):
-        editor = self.editors.pop(name)
+        editor = editors.pop(name)
         self.gui.central.close_editor(editor)
         editor.break_cycles()
 
@@ -303,7 +302,7 @@ class Boss(QObject):
         if ed is None:
             return
         name = None
-        for n, x in self.editors.iteritems():
+        for n, x in editors.iteritems():
             if x is ed:
                 name = n
                 break
@@ -317,7 +316,7 @@ class Boss(QObject):
         container = clone_container(c, tdir)
         self.save_manager.schedule(tdir, container)
         is_modified = False
-        for ed in self.editors.itervalues():
+        for ed in editors.itervalues():
             if ed.is_modified:
                 is_modified = True
                 break

src/calibre/gui2/tweak_book/preview.py

@@ -9,9 +9,13 @@ __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 from threading import Thread
 from Queue import Queue, Empty
 
-from PyQt4.Qt import (QWidget, QVBoxLayout, QApplication, QSize, QNetworkAccessManager)
+from PyQt4.Qt import (
+    QWidget, QVBoxLayout, QApplication, QSize, QNetworkAccessManager,
+    QNetworkReply, QTimer, QNetworkRequest, QUrl)
 from PyQt4.QtWebKit import QWebView
 
+from calibre.constants import iswindows
+from calibre.gui2.tweak_book import current_container, editors
 from calibre.gui2.viewer.documentview import apply_settings
 from calibre.gui2.viewer.config import config
 from calibre.utils.ipc.simple_worker import offload_worker
@@ -56,6 +60,47 @@ class ParseWorker(Thread):
     def shutdown(self):
         self.requests.put(shutdown)
 
+
+class LocalNetworkReply(QNetworkReply):
+
+    def __init__(self, parent, request, mime_type, data):
+        QNetworkReply.__init__(self, parent)
+        self.setOpenMode(QNetworkReply.ReadOnly | QNetworkReply.Unbuffered)
+        self.__data = data
+        self.setRequest(request)
+        self.setUrl(request.url())
+        self.setHeader(QNetworkRequest.ContentTypeHeader, mime_type)
+        self.setHeader(QNetworkRequest.ContentLengthHeader, len(self.__data))
+        QTimer.singleShot(0, self.finalize_reply)
+
+    def bytesAvailable(self):
+        return len(self.__data)
+
+    def isSequential(self):
+        return True
+
+    def abort(self):
+        pass
+
+    def readData(self, maxlen):
+        ans, self.__data = self.__data[:maxlen], self.__data[maxlen:]
+        return ans
+    read = readData
+
+    def finalize_reply(self):
+        self.setFinished(True)
+        self.setAttribute(QNetworkRequest.HttpStatusCodeAttribute, 200)
+        self.setAttribute(QNetworkRequest.HttpReasonPhraseAttribute, "Ok")
+        self.metaDataChanged.emit()
+        self.downloadProgress.emit(len(self.__data), len(self.__data))
+        self.readyRead.emit()
+        self.finished.emit()
+
+def get_data(name):
+    if name in editors:
+        return editors[name].data
+    return current_container().open(name).read()
+
 class NetworkAccessManager(QNetworkAccessManager):
 
     OPERATION_NAMES = {getattr(QNetworkAccessManager, '%sOperation'%x) :
@@ -65,7 +110,19 @@ class NetworkAccessManager(QNetworkAccessManager):
 
     def createRequest(self, operation, request, data):
         url = unicode(request.url().toString())
-        print (url)
+        if url.startswith('file://'):
+            path = url[7:]
+            if iswindows and path.startswith('/'):
+                path = path[1:]
+            c = current_container()
+            name = c.abspath_to_name(path)
+            if c.has_name(name):
+                try:
+                    return LocalNetworkReply(self, request, c.mime_map.get(name, 'application/octet-stream'),
+                                             get_data(name) if operation == self.GetOperation else b'')
+                except Exception:
+                    import traceback
+                    traceback.print_stack()
         return QNetworkAccessManager.createRequest(self, operation, request,
                 data)
 
@@ -78,9 +135,17 @@ class WebView(QWebView):
         settings = self.page().settings()
         apply_settings(settings, config().parse())
         settings.setMaximumPagesInCache(0)
+        settings.setAttribute(settings.JavaEnabled, False)
+        settings.setAttribute(settings.PluginsEnabled, False)
+        settings.setAttribute(settings.PrivateBrowsingEnabled, True)
+        settings.setAttribute(settings.JavascriptCanOpenWindows, False)
+        settings.setAttribute(settings.JavascriptCanAccessClipboard, False)
+        settings.setAttribute(settings.LinksIncludedInFocusChain, False)
+        settings.setAttribute(settings.DeveloperExtrasEnabled, True)
+        settings.setDefaultTextEncoding('utf-8')
+
         self.setHtml('<p>')
-        self.nam = NetworkAccessManager(self)
+        self.page().setNetworkAccessManager(NetworkAccessManager(self))
-        self.page().setNetworkAccessManager(self.nam)
 
     def sizeHint(self):
         return self._size_hint
@@ -96,3 +161,8 @@ class Preview(QWidget):
         self.view = WebView(self)
         l.addWidget(self.view)
 
+    def show(self, name):
+        data = get_data(name)
+        c = current_container()
+        self.view.setHtml(data, QUrl.fromLocalFile(c.name_to_abspath(name)))
+