eric6/WebBrowser/Network/EricSchemeHandler.py

# -*- coding: utf-8 -*-

# Copyright (c) 2016 - 2021 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing a scheme handler for the eric: scheme.
"""

from PyQt5.QtCore import pyqtSignal, QBuffer, QIODevice, QUrlQuery, QMutex
from PyQt5.QtWebEngineCore import QWebEngineUrlSchemeHandler

from E5Gui.E5Application import e5App

from E5Utilities.E5MutexLocker import E5MutexLocker

from ..Tools.WebBrowserTools import (
    getHtmlPage, getJavascript, pixmapFileToDataUrl
)

_SupportedPages = [
    "adblock",                      # error page for URLs blocked by AdBlock
    "home", "start", "startpage",   # eric home page
    "speeddial",                    # eric speeddial
]


class EricSchemeHandler(QWebEngineUrlSchemeHandler):
    """
    Class implementing a scheme handler for the eric: scheme.
    """
    def __init__(self, parent=None):
        """
        Constructor
        
        @param parent reference to the parent object
        @type QObject
        """
        super(EricSchemeHandler, self).__init__(parent)
        
        self.__replies = []
    
    def requestStarted(self, job):
        """
        Public method handling the URL request.
        
        @param job URL request job
        @type QWebEngineUrlRequestJob
        """
        reply = EricSchemeReply(job)
        reply.closed.connect(lambda: self.__replyClosed(reply))
        self.__replies.append(reply)
        job.reply(b"text/html", reply)
    
    def __replyClosed(self, reply):
        """
        Private slot handling the closed signal of a reply.
        
        @param reply reference to the network reply
        @type EricSchemeReply
        """
        if reply in self.__replies:
            self.__replies.remove(reply)


class EricSchemeReply(QIODevice):
    """
    Class implementing a reply for a requested eric: page.
    
    @signal closed emitted to signal that the web engine has read
        the data
    """
    closed = pyqtSignal()
    
    _speedDialPage = ""
    
    def __init__(self, job, parent=None):
        """
        Constructor
        
        @param job reference to the URL request
        @type QWebEngineUrlRequestJob
        @param parent reference to the parent object
        @type QObject
        """
        super(EricSchemeReply, self).__init__(parent)
        
        self.__loaded = False
        self.__job = job
        self.__mutex = QMutex()
        
        self.__pageName = self.__job.requestUrl().path()
        self.__buffer = QBuffer()
        
        self.__loadPage()
    
    def __loadPage(self):
        """
        Private method to load the requested page.
        """
        if self.__loaded:
            return
        
        with E5MutexLocker(self.__mutex):
            if self.__pageName == "adblock":
                contents = self.__adBlockPage()
            elif self.__pageName in ["home", "start", "startpage"]:
                contents = self.__startPage()
            elif self.__pageName == "speeddial":
                contents = self.__speedDialPage()
            else:
                contents = self.__errorPage()
            
            self.__buffer.setData(contents.encode("utf-8"))
            self.__buffer.open(QIODevice.ReadOnly)
            self.open(QIODevice.ReadOnly)
        
        self.readyRead.emit()
        
        self.__loaded = True
    
    def bytesAvailable(self):
        """
        Public method to get the number of available bytes.
        
        @return number of available bytes
        @rtype int
        """
        with E5MutexLocker(self.__mutex):
            return self.__buffer.bytesAvailable()
    
    def readData(self, maxlen):
        """
        Public method to retrieve data from the reply object.
        
        @param maxlen maximum number of bytes to read (integer)
        @return string containing the data (bytes)
        """
        with E5MutexLocker(self.__mutex):
            return self.__buffer.read(maxlen)
    
    def close(self):
        """
        Public method used to cloase the reply.
        """
        super(EricSchemeReply, self).close()
        self.closed.emit()
    
    def __adBlockPage(self):
        """
        Private method to build the AdBlock page.
        
        @return built AdBlock page
        @rtype str
        """
        query = QUrlQuery(self.__job.requestUrl())
        rule = query.queryItemValue("rule")
        subscription = query.queryItemValue("subscription")
        title = self.tr("Content blocked by AdBlock Plus")
        message = self.tr(
            "Blocked by rule: <i>{0} ({1})</i>").format(rule, subscription)
        
        page = getHtmlPage("adblockPage.html")
        page = page.replace(
            "@FAVICON@", pixmapFileToDataUrl("adBlockPlus16.png", True))
        page = page.replace(
            "@IMAGE@", pixmapFileToDataUrl("adBlockPlus64.png", True))
        page = page.replace("@TITLE@", title)
        page = page.replace("@MESSAGE@", message)
        
        return page
    
    def __errorPage(self):
        """
        Private method to build the Error page.
        
        @return built Error page
        @rtype str
        """
        page = getHtmlPage("ericErrorPage.html")
        page = page.replace(
            "@FAVICON@", pixmapFileToDataUrl("ericWeb16.png", True))
        page = page.replace(
            "@IMAGE@", pixmapFileToDataUrl("ericWeb32.png", True))
        page = page.replace(
            "@TITLE@", self.tr("Error accessing eric: URL"))
        page = page.replace(
            "@MESSAGE@", self.tr(
                "The special URL <strong>{0}</strong> is not supported."
                " Please use one of these."
            ).format(self.__job.requestUrl().toDisplayString())
        )
        page = page.replace(
            "@ERICLIST@", "<br/>".join([
                '<a href="eric:{0}">{0}</a>'.format(u)
                for u in sorted(_SupportedPages)
            ])
        )
        
        return page
    
    def __startPage(self):
        """
        Private method to build the Start page.
        
        @return built Start page
        @rtype str
        """
        page = getHtmlPage("startPage.html")
        page = page.replace(
            "@FAVICON@", pixmapFileToDataUrl("ericWeb16.png", True))
        page = page.replace(
            "@IMAGE@", pixmapFileToDataUrl("ericWeb32.png", True))
        page = page.replace(
            "@TITLE@", self.tr("Welcome to eric Web Browser!"))
        page = page.replace("@ERIC_LINK@", self.tr("About eric"))
        page = page.replace("@HEADER_TITLE@", self.tr("eric Web Browser"))
        page = page.replace("@SUBMIT@", self.tr("Search!"))
        if e5App().isLeftToRight():
            ltr = "LTR"
        else:
            ltr = "RTL"
        page = page.replace("@QT_LAYOUT_DIRECTION@", ltr)
        
        return page
    
    def __speedDialPage(self):
        """
        Private method to create the Speeddial page.
        
        @return prepared speeddial page
        @rtype str
        """
        if not self._speedDialPage:
            page = getHtmlPage("speeddialPage.html")
            page = page.replace(
                "@FAVICON@", pixmapFileToDataUrl("ericWeb16.png", True))
            page = page.replace(
                "@IMG_PLUS@", pixmapFileToDataUrl("plus.png", True))
            page = page.replace(
                "@IMG_CLOSE@", pixmapFileToDataUrl("close.png", True))
            page = page.replace(
                "@IMG_EDIT@", pixmapFileToDataUrl("edit.png", True))
            page = page.replace(
                "@IMG_RELOAD@", pixmapFileToDataUrl("reload.png", True))
            page = page.replace(
                "@IMG_SETTINGS@", pixmapFileToDataUrl("setting.png", True))
            page = page.replace(
                "@LOADING-IMG@", pixmapFileToDataUrl("loading.gif", True))
            page = page.replace(
                "@BOX-BORDER@",
                pixmapFileToDataUrl("box-border-small.png", True))
            
            page = page.replace("@JQUERY@", getJavascript("jquery.js"))
            page = page.replace("@JQUERY-UI@", getJavascript("jquery-ui.js"))
            
            page = page.replace("@SITE-TITLE@", self.tr("Speed Dial"))
            page = page.replace("@URL@", self.tr("URL"))
            page = page.replace("@TITLE@", self.tr("Title"))
            page = page.replace("@APPLY@", self.tr("Apply"))
            page = page.replace("@CLOSE@", self.tr("Close"))
            page = page.replace("@NEW-PAGE@", self.tr("New Page"))
            page = page.replace("@TITLE-EDIT@", self.tr("Edit"))
            page = page.replace("@TITLE-REMOVE@", self.tr("Remove"))
            page = page.replace("@TITLE-RELOAD@", self.tr("Reload"))
            page = page.replace("@TITLE-WARN@",
                                self.tr("Are you sure to remove this"
                                        " speed dial?"))
            page = page.replace("@TITLE-WARN-REL@",
                                self.tr("Are you sure you want to reload"
                                        " all speed dials?"))
            page = page.replace("@TITLE-FETCHTITLE@",
                                self.tr("Load title from page"))
            page = page.replace("@SETTINGS-TITLE@",
                                self.tr("Speed Dial Settings"))
            page = page.replace("@ADD-TITLE@", self.tr("Add New Page"))
            page = page.replace("@TXT_NRROWS@",
                                self.tr("Maximum pages in a row:"))
            page = page.replace("@TXT_SDSIZE@",
                                self.tr("Change size of pages:"))
            page = page.replace("@JAVASCRIPT_DISABLED@",
                                self.tr("SpeedDial requires enabled"
                                        " JavaScript."))
            
            self._speedDialPage = page
        
        from WebBrowser.WebBrowserWindow import WebBrowserWindow
        dial = WebBrowserWindow.speedDial()
        page = (
            self._speedDialPage
            .replace("@INITIAL-SCRIPT@", dial.initialScript())
            .replace("@ROW-PAGES@", str(dial.pagesInRow()))
            .replace("@SD-SIZE@", str(dial.sdSize()))
        )
        
        return page