# -*- coding: utf-8 -*-
# Copyright: Damien Elmes <anki@ichi2.net>
# License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
import re
import os
import urllib2
import ctypes
import urllib

from anki.lang import _
from aqt.qt import *
from anki.utils import stripHTML, isWin, isMac, namedtmp, json, stripHTMLMedia
import anki.sound
from anki.hooks import runHook, runFilter
from aqt.sound import getAudio
from aqt.webview import AnkiWebView
from aqt.utils import shortcut, showInfo, showWarning, getBase, getFile, \
    openHelp, tooltip
import aqt
import anki.js
from BeautifulSoup import BeautifulSoup

pics = ("jpg", "jpeg", "png", "tif", "tiff", "gif", "svg")
audio =  ("wav", "mp3", "ogg", "flac", "mp4", "swf", "mov", "mpeg", "mkv")

_html = """
<html><head>%s<style>
.field {
  border: 1px solid #aaa; background:#fff; color:#000; padding: 5px;
}
/* prevent floated images from being displayed outside field */
.field:after {
    content: "";
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;
}
.fname { vertical-align: middle; padding: 0; }
img { max-width: 90%%; }
body { margin: 5px; }
</style><script>
%s

var currentField = null;
var changeTimer = null;
var dropTarget = null;

String.prototype.format = function() {
    var args = arguments;
    return this.replace(/\{\d+\}/g, function(m){
            return args[m.match(/\d+/)]; });
};

function onKey() {
    // esc clears focus, allowing dialog to close
    if (window.event.which == 27) {
        currentField.blur();
        return;
    }
    clearChangeTimer();
    if (currentField.innerHTML == "<div><br></div>") {
        // fix empty div bug. slight flicker, but must be done in a timer
        changeTimer = setTimeout(function () {
            currentField.innerHTML = "<br>";
            sendState();
            saveField("key"); }, 1);
    } else {
        changeTimer = setTimeout(function () {
            sendState();
            saveField("key"); }, 600);
    }
};

function sendState() {
    var r = {
        'bold': document.queryCommandState("bold"),
        'italic': document.queryCommandState("italic"),
        'under': document.queryCommandState("underline"),
        'super': document.queryCommandState("superscript"),
        'sub': document.queryCommandState("subscript"),
        'col': document.queryCommandValue("forecolor")
    };
    py.run("state:" + JSON.stringify(r));
};

function setFormat(cmd, arg, nosave) {
    document.execCommand(cmd, false, arg);
    if (!nosave) {
        saveField('key');
    }
};

function clearChangeTimer() {
    if (changeTimer) {
        clearTimeout(changeTimer);
        changeTimer = null;
    }
};

function onFocus(elem) {
    currentField = elem;
    py.run("focus:" + currentField.id.substring(1));
    // don't adjust cursor on mouse clicks
    if (mouseDown) { return; }
    // do this twice so that there's no flicker on newer versions
    caretToEnd();
    // need to do this in a timeout for older qt versions
    setTimeout(function () { caretToEnd() }, 1);
    // scroll if bottom of element off the screen
    function pos(obj) {
    	var cur = 0;
        do {
          cur += obj.offsetTop;
         } while (obj = obj.offsetParent);
    	return cur;
    }
    var y = pos(elem);
    if ((window.pageYOffset+window.innerHeight) < (y+elem.offsetHeight) ||
        window.pageYOffset > y) {
        window.scroll(0,y+elem.offsetHeight-window.innerHeight);
    }
}

function focusField(n) {
    $("#f"+n).focus();
}

function onDragOver(elem) {
    // if we focus the target element immediately, the drag&drop turns into a
    // copy, so note it down for later instead
    dropTarget = elem;
}

function caretToEnd() {
    var r = document.createRange()
    r.selectNodeContents(currentField);
    r.collapse(false);
    var s = document.getSelection();
    s.removeAllRanges();
    s.addRange(r);
};

function onBlur() {
    if (currentField) {
        saveField("blur");
    }
    clearChangeTimer();
    // if we lose focus, assume the last field is still targeted
    //currentField = null;
};

function saveField(type) {
    if (!currentField) {
        // no field has been focused yet
        return;
    }
    // type is either 'blur' or 'key'
    py.run(type + ":" + currentField.innerHTML);
    clearChangeTimer();
};

function wrappedExceptForWhitespace(text, front, back) {
    var match = text.match(/^(\s*)([^]*?)(\s*)$/);
    return match[1] + front + match[2] + back + match[3];
};

function wrap(front, back) {
    var s = window.getSelection();
    var r = s.getRangeAt(0);
    var content = r.cloneContents();
    var span = document.createElement("span")
    span.appendChild(content);
    var new_ = wrappedExceptForWhitespace(span.innerHTML, front, back);
    setFormat("inserthtml", new_);
    if (!span.innerHTML) {
        // run with an empty selection; move cursor back past postfix
        r = s.getRangeAt(0);
        r.setStart(r.startContainer, r.startOffset - back.length);
        r.collapse(true);
        s.removeAllRanges();
        s.addRange(r);
    }
};

function setFields(fields, focusTo) {
    var txt = "";
    for (var i=0; i<fields.length; i++) {
        var n = fields[i][0];
        var f = fields[i][1];
        if (!f) {
            f = "<br>";
        }
        txt += "<tr><td class=fname>{0}</td></tr><tr><td width=100%%>".format(n);
        txt += "<div id=f{0} onkeydown='onKey();' onmouseup='onKey();'".format(i);
        txt += " onfocus='onFocus(this);' onblur='onBlur();' class=field ";
        txt += "ondragover='onDragOver(this);' ";
        txt += "contentEditable=true class=field>{0}</div>".format(f);
        txt += "</td></tr>";
    }
    $("#fields").html("<table cellpadding=0 width=100%%>"+txt+"</table>");
    if (!focusTo) {
        focusTo = 0;
    }
    if (focusTo >= 0) {
        $("#f"+focusTo).focus();
    }
};

function setBackgrounds(cols) {
    for (var i=0; i<cols.length; i++) {
        $("#f"+i).css("background", cols[i]);
    }
}

function setFonts(fonts) {
    for (var i=0; i<fonts.length; i++) {
        $("#f"+i).css("font-family", fonts[i][0]);
        $("#f"+i).css("font-size", fonts[i][1]);
        $("#f"+i)[0].dir = fonts[i][2] ? "rtl" : "ltr";
    }
}

function showDupes() {
    $("#dupes").show();
}

function hideDupes() {
    $("#dupes").hide();
}

var mouseDown = 0;

$(function () {
document.body.onmousedown = function () {
    mouseDown++;
}

document.body.onmouseup = function () {
    mouseDown--;
}

document.onclick = function (evt) {
    var src = window.event.srcElement;
    if (src.tagName == "IMG") {
        // image clicked; find contenteditable parent
        var p = src;
        while (p = p.parentNode) {
            if (p.className == "field") {
                $("#"+p.id).focus();
                break;
            }
        }
    }
}

});

</script></head><body>
<div id="fields"></div>
<div id="dupes"><a href="#" onclick="py.run('dupes');return false;">%s</a></div>
</body></html>
"""

# caller is responsible for resetting note on reset
class Editor(object):
    def __init__(self, mw, widget, parentWindow, addMode=False):
        self.mw = mw
        self.widget = widget
        self.parentWindow = parentWindow
        self.note = None
        self.stealFocus = True
        self.addMode = addMode
        self._loaded = False
        self.currentField = 0
        # current card, for card layout
        self.card = None
        self.setupOuter()
        self.setupButtons()
        self.setupWeb()
        self.setupTags()
        self.setupKeyboard()

    # Initial setup
    ############################################################

    def setupOuter(self):
        l = QVBoxLayout()
        l.setMargin(0)
        l.setSpacing(0)
        self.widget.setLayout(l)
        self.outerLayout = l

    def setupWeb(self):
        self.web = EditorWebView(self.widget, self)
        self.web.allowDrops = True
        self.web.setBridge(self.bridge)
        self.outerLayout.addWidget(self.web, 1)
        # pick up the window colour
        p = self.web.palette()
        p.setBrush(QPalette.Base, Qt.transparent)
        self.web.page().setPalette(p)
        self.web.setAttribute(Qt.WA_OpaquePaintEvent, False)

    # Top buttons
    ######################################################################

    def _addButton(self, name, func, key=None, tip=None, size=True, text="",
                   check=False, native=False, canDisable=True):
        b = QPushButton(text)
        if check:
            b.connect(b, SIGNAL("clicked(bool)"), func)
        else:
            b.connect(b, SIGNAL("clicked()"), func)
        if size:
            b.setFixedHeight(20)
            b.setFixedWidth(20)
        if not native:
            if self.plastiqueStyle:
               b.setStyle(self.plastiqueStyle)
            b.setFocusPolicy(Qt.NoFocus)
        else:
            b.setAutoDefault(False)
        if not text:
            b.setIcon(QIcon(":/icons/%s.png" % name))
        if key:
            b.setShortcut(QKeySequence(key))
        if tip:
            b.setToolTip(shortcut(tip))
        if check:
            b.setCheckable(True)
        self.iconsBox.addWidget(b)
        if canDisable:
            self._buttons[name] = b
        return b

    def setupButtons(self):
        self._buttons = {}
        # button styles for mac
        if not isMac:
            self.plastiqueStyle = QStyleFactory.create("plastique")
            if not self.plastiqueStyle:
                # plastique was removed in qt5
                self.plastiqueStyle = QStyleFactory.create("fusion")
            self.widget.setStyle(self.plastiqueStyle)
        else:
            self.plastiqueStyle = None
        # icons
        self.iconsBox = QHBoxLayout()
        if not isMac:
            self.iconsBox.setMargin(6)
            self.iconsBox.setSpacing(0)
        else:
            self.iconsBox.setMargin(0)
            self.iconsBox.setSpacing(14)
        self.outerLayout.addLayout(self.iconsBox)
        b = self._addButton
        b("fields", self.onFields, "",
          shortcut(_("Customize Fields")), size=False, text=_("Fields..."),
          native=True, canDisable=False)
        self.iconsBox.addItem(QSpacerItem(6,1, QSizePolicy.Fixed))
        b("layout", self.onCardLayout, _("Ctrl+L"),
          shortcut(_("Customize Cards (Ctrl+L)")),
          size=False, text=_("Cards..."), native=True, canDisable=False)
        # align to right
        self.iconsBox.addItem(QSpacerItem(20,1, QSizePolicy.Expanding))
        b("text_bold", self.toggleBold, _("Ctrl+B"), _("Bold text (Ctrl+B)"),
          check=True)
        b("text_italic", self.toggleItalic, _("Ctrl+I"), _("Italic text (Ctrl+I)"),
          check=True)
        b("text_under", self.toggleUnderline, _("Ctrl+U"),
          _("Underline text (Ctrl+U)"), check=True)
        b("text_super", self.toggleSuper, _("Ctrl+Shift+="),
          _("Superscript (Ctrl+Shift+=)"), check=True)
        b("text_sub", self.toggleSub, _("Ctrl+="),
          _("Subscript (Ctrl+=)"), check=True)
        b("text_clear", self.removeFormat, _("Ctrl+R"),
          _("Remove formatting (Ctrl+R)"))
        but = b("foreground", self.onForeground, _("F7"), text=" ")
        but.setToolTip(_("Set foreground colour (F7)"))
        self.setupForegroundButton(but)
        but = b("change_colour", self.onChangeCol, _("F8"),
          _("Change colour (F8)"), text=u"▾")
        but.setFixedWidth(12)
        but = b("cloze", self.onCloze, _("Ctrl+Shift+C"),
                _("Cloze deletion (Ctrl+Shift+C)"), text="[...]")
        but.setFixedWidth(24)
        s = self.clozeShortcut2 = QShortcut(
            QKeySequence(_("Ctrl+Alt+Shift+C")), self.parentWindow)
        s.connect(s, SIGNAL("activated()"), self.onCloze)
        # fixme: better image names
        b("mail-attachment", self.onAddMedia, _("F3"),
          _("Attach pictures/audio/video (F3)"))
        b("media-record", self.onRecSound, _("F5"), _("Record audio (F5)"))
        b("adv", self.onAdvanced, text=u"▾")
        s = QShortcut(QKeySequence("Ctrl+T, T"), self.widget)
        s.connect(s, SIGNAL("activated()"), self.insertLatex)
        s = QShortcut(QKeySequence("Ctrl+T, E"), self.widget)
        s.connect(s, SIGNAL("activated()"), self.insertLatexEqn)
        s = QShortcut(QKeySequence("Ctrl+T, M"), self.widget)
        s.connect(s, SIGNAL("activated()"), self.insertLatexMathEnv)
        s = QShortcut(QKeySequence("Ctrl+Shift+X"), self.widget)
        s.connect(s, SIGNAL("activated()"), self.onHtmlEdit)
        # tags
        s = QShortcut(QKeySequence("Ctrl+Shift+T"), self.widget)
        s.connect(s, SIGNAL("activated()"), lambda: self.tags.setFocus())
        runHook("setupEditorButtons", self)

    def enableButtons(self, val=True):
        for b in self._buttons.values():
            b.setEnabled(val)

    def disableButtons(self):
        self.enableButtons(False)

    def onFields(self):
        from aqt.fields import FieldDialog
        self.saveNow()
        FieldDialog(self.mw, self.note, parent=self.parentWindow)

    def onCardLayout(self):
        from aqt.clayout import CardLayout
        self.saveNow()
        if self.card:
            ord = self.card.ord
        else:
            ord = 0
        # passing parentWindow leads to crash on windows at the moment
        if isWin:
            parent=None
        else:
            parent=self.parentWindow
        CardLayout(self.mw, self.note, ord=ord, parent=parent,
               addMode=self.addMode)
        self.loadNote()
        if isWin:
            self.parentWindow.activateWindow()

    # JS->Python bridge
    ######################################################################

    def bridge(self, str):
        if not self.note or not runHook:
            # shutdown
            return
        # focus lost or key/button pressed?
        if str.startswith("blur") or str.startswith("key"):
            (type, txt) = str.split(":", 1)
            txt = self.mungeHTML(txt)
            # misbehaving apps may include a null byte in the text
            txt = txt.replace("\x00", "")
            # reverse the url quoting we added to get images to display
            txt = unicode(urllib2.unquote(
                txt.encode("utf8")), "utf8", "replace")
            self.note.fields[self.currentField] = txt
            if not self.addMode:
                self.note.flush()
                self.mw.requireReset()
            if type == "blur":
                self.disableButtons()
                # run any filters
                if runFilter(
                    "editFocusLost", False, self.note, self.currentField):
                    # something updated the note; schedule reload
                    def onUpdate():
                        self.stealFocus = True
                        self.loadNote()
                        self.checkValid()
                    self.mw.progress.timer(100, onUpdate, False)
                else:
                    self.checkValid()
            else:
                runHook("editTimer", self.note)
                self.checkValid()
        # focused into field?
        elif str.startswith("focus"):
            (type, num) = str.split(":", 1)
            self.enableButtons()
            self.currentField = int(num)
            runHook("editFocusGained", self.note, self.currentField)
        # state buttons changed?
        elif str.startswith("state"):
            (cmd, txt) = str.split(":", 1)
            r = json.loads(txt)
            self._buttons['text_bold'].setChecked(r['bold'])
            self._buttons['text_italic'].setChecked(r['italic'])
            self._buttons['text_under'].setChecked(r['under'])
            self._buttons['text_super'].setChecked(r['super'])
            self._buttons['text_sub'].setChecked(r['sub'])
        elif str.startswith("dupes"):
            self.showDupes()
        else:
            print str

    def mungeHTML(self, txt):
        if txt == "<br>":
            txt = ""
        return self._filterHTML(txt, localize=False)

    # Setting/unsetting the current note
    ######################################################################

    def _loadFinished(self, w):
        self._loaded = True
        if self.note:
            self.loadNote()

    def setNote(self, note, hide=True, focus=False):
        "Make NOTE the current note."
        self.note = note
        self.currentField = 0
        self.disableButtons()
        if focus:
            self.stealFocus = True
        # change timer
        if self.note:
            self.web.setHtml(_html % (
                getBase(self.mw.col), anki.js.jquery,
                _("Show Duplicates")), loadCB=self._loadFinished)
            self.updateTags()
            self.updateKeyboard()
        else:
            self.hideCompleters()
            if hide:
                self.widget.hide()

    def loadNote(self):
        if not self.note:
            return
        if self.stealFocus:
            field = self.currentField
        else:
            field = -1
        if not self._loaded:
            # will be loaded when page is ready
            return
        data = []
        for fld, val in self.note.items():
            data.append((fld, self.mw.col.media.escapeImages(val)))
        self.web.eval("setFields(%s, %d);" % (
            json.dumps(data), field))
        self.web.eval("setFonts(%s);" % (
            json.dumps(self.fonts())))
        self.checkValid()
        self.widget.show()
        if self.stealFocus:
            self.web.setFocus()
            self.stealFocus = False

    def focus(self):
        self.web.setFocus()

    def fonts(self):
        return [(f['font'], f['size'], f['rtl'])
                for f in self.note.model()['flds']]

    def saveNow(self):
        "Must call this before adding cards, closing dialog, etc."
        if not self.note:
            return
        self.saveTags()
        if self.mw.app.focusWidget() != self.web:
            # if no fields are focused, there's nothing to save
            return
        # move focus out of fields and save tags
        self.parentWindow.setFocus()
        # and process events so any focus-lost hooks fire
        self.mw.app.processEvents()

    def checkValid(self):
        cols = []
        err = None
        for f in self.note.fields:
            cols.append("#fff")
        err = self.note.dupeOrEmpty()
        if err == 2:
            cols[0] = "#fcc"
            self.web.eval("showDupes();")
        else:
            self.web.eval("hideDupes();")
        self.web.eval("setBackgrounds(%s);" % json.dumps(cols))

    def showDupes(self):
        contents = stripHTMLMedia(self.note.fields[0])
        browser = aqt.dialogs.open("Browser", self.mw)
        browser.form.searchEdit.lineEdit().setText(
            '"dupe:%s,%s"' % (self.note.model()['id'],
                              contents))
        browser.onSearch()

    def fieldsAreBlank(self):
        if not self.note:
            return True
        m = self.note.model()
        for c, f in enumerate(self.note.fields):
            if f and not m['flds'][c]['sticky']:
                return False
        return True

    # HTML editing
    ######################################################################

    def onHtmlEdit(self):
        self.saveNow()
        d = QDialog(self.widget)
        form = aqt.forms.edithtml.Ui_Dialog()
        form.setupUi(d)
        d.connect(form.buttonBox, SIGNAL("helpRequested()"),
                 lambda: openHelp("editor"))
        form.textEdit.setPlainText(self.note.fields[self.currentField])
        form.textEdit.moveCursor(QTextCursor.End)
        d.exec_()
        html = form.textEdit.toPlainText()
        # filter html through beautifulsoup so we can strip out things like a
        # leading </div>
        html = unicode(BeautifulSoup(html))
        self.note.fields[self.currentField] = html
        self.loadNote()
        # focus field so it's saved
        self.web.setFocus()
        self.web.eval("focusField(%d);" % self.currentField)

    # Tag handling
    ######################################################################

    def setupTags(self):
        import aqt.tagedit
        g = QGroupBox(self.widget)
        g.setFlat(True)
        tb = QGridLayout()
        tb.setSpacing(12)
        tb.setMargin(6)
        # tags
        l = QLabel(_("Tags"))
        tb.addWidget(l, 1, 0)
        self.tags = aqt.tagedit.TagEdit(self.widget)
        self.tags.connect(self.tags, SIGNAL("lostFocus"),
                          self.saveTags)
        self.tags.setToolTip(shortcut(_("Jump to tags with Ctrl+Shift+T")))
        tb.addWidget(self.tags, 1, 1)
        g.setLayout(tb)
        self.outerLayout.addWidget(g)

    def updateTags(self):
        if self.tags.col != self.mw.col:
            self.tags.setCol(self.mw.col)
        if not self.tags.text() or not self.addMode:
            self.tags.setText(self.note.stringTags().strip())

    def saveTags(self):
        if not self.note:
            return
        self.note.tags = self.mw.col.tags.canonify(
            self.mw.col.tags.split(self.tags.text()))
        self.tags.setText(self.mw.col.tags.join(self.note.tags).strip())
        if not self.addMode:
            self.note.flush()
        runHook("tagsUpdated", self.note)

    def saveAddModeVars(self):
        if self.addMode:
            # save tags to model
            m = self.note.model()
            m['tags'] = self.note.tags
            self.mw.col.models.save(m)

    def hideCompleters(self):
        self.tags.hideCompleter()

    # Format buttons
    ######################################################################

    def toggleBold(self, bool):
        self.web.eval("setFormat('bold');")

    def toggleItalic(self, bool):
        self.web.eval("setFormat('italic');")

    def toggleUnderline(self, bool):
        self.web.eval("setFormat('underline');")

    def toggleSuper(self, bool):
        self.web.eval("setFormat('superscript');")

    def toggleSub(self, bool):
        self.web.eval("setFormat('subscript');")

    def removeFormat(self):
        self.web.eval("setFormat('removeFormat');")

    def onCloze(self):
        # check that the model is set up for cloze deletion
        if '{{cloze:' not in self.note.model()['tmpls'][0]['qfmt']:
            if self.addMode:
                tooltip(_("Warning, cloze deletions will not work until "
                "you switch the type at the top to Cloze."))
            else:
                showInfo(_("""\
To make a cloze deletion on an existing note, you need to change it \
to a cloze type first, via Edit>Change Note Type."""))
                return
        # find the highest existing cloze
        highest = 0
        for name, val in self.note.items():
            m = re.findall("\{\{c(\d+)::", val)
            if m:
                highest = max(highest, sorted([int(x) for x in m])[-1])
        # reuse last?
        if not self.mw.app.keyboardModifiers() & Qt.AltModifier:
            highest += 1
        # must start at 1
        highest = max(1, highest)
        self.web.eval("wrap('{{c%d::', '}}');" % highest)

    # Foreground colour
    ######################################################################

    def setupForegroundButton(self, but):
        self.foregroundFrame = QFrame()
        self.foregroundFrame.setAutoFillBackground(True)
        self.foregroundFrame.setFocusPolicy(Qt.NoFocus)
        self.fcolour = self.mw.pm.profile.get("lastColour", "#00f")
        self.onColourChanged()
        hbox = QHBoxLayout()
        hbox.addWidget(self.foregroundFrame)
        hbox.setMargin(5)
        but.setLayout(hbox)

    # use last colour
    def onForeground(self):
        self._wrapWithColour(self.fcolour)

    # choose new colour
    def onChangeCol(self):
        new = QColorDialog.getColor(QColor(self.fcolour), None)
        # native dialog doesn't refocus us for some reason
        self.parentWindow.activateWindow()
        if new.isValid():
            self.fcolour = new.name()
            self.onColourChanged()
            self._wrapWithColour(self.fcolour)

    def _updateForegroundButton(self):
        self.foregroundFrame.setPalette(QPalette(QColor(self.fcolour)))

    def onColourChanged(self):
        self._updateForegroundButton()
        self.mw.pm.profile['lastColour'] = self.fcolour

    def _wrapWithColour(self, colour):
        self.web.eval("setFormat('forecolor', '%s')" % colour)

    # Audio/video/images
    ######################################################################

    def onAddMedia(self):
        key = (_("Media") +
               " (*.jpg *.png *.gif *.tiff *.svg *.tif *.jpeg "+
               "*.mp3 *.ogg *.wav *.avi *.ogv *.mpg *.mpeg *.mov *.mp4 " +
               "*.mkv *.ogx *.ogv *.oga *.flv *.swf *.flac)")
        def accept(file):
            self.addMedia(file, canDelete=True)
        file = getFile(self.widget, _("Add Media"), accept, key, key="media")
        self.parentWindow.activateWindow()

    def addMedia(self, path, canDelete=False):
        html = self._addMedia(path, canDelete)
        self.web.eval("setFormat('inserthtml', %s);" % json.dumps(html))

    def _addMedia(self, path, canDelete=False):
        "Add to media folder and return local img or sound tag."
        # copy to media folder
        fname = self.mw.col.media.addFile(path)
        # remove original?
        if canDelete and self.mw.pm.profile['deleteMedia']:
            if os.path.abspath(fname) != os.path.abspath(path):
                try:
                    os.unlink(path)
                except:
                    pass
        # return a local html link
        return self.fnameToLink(fname)

    def onRecSound(self):
        try:
            file = getAudio(self.widget)
        except Exception, e:
            showWarning(_(
                "Couldn't record audio. Have you installed lame and sox?") +
                        "\n\n" + repr(str(e)))
            return
        self.addMedia(file)

    # Media downloads
    ######################################################################

    def urlToLink(self, url):
        fname = self.urlToFile(url)
        if not fname:
            return ""
        return self.fnameToLink(fname)

    def fnameToLink(self, fname):
        ext = fname.split(".")[-1].lower()
        if ext in pics:
            name = urllib.quote(fname.encode("utf8"))
            return '<img src="%s">' % name
        else:
            anki.sound.play(fname)
            return '[sound:%s]' % fname

    def urlToFile(self, url):
        l = url.lower()
        for suffix in pics+audio:
            if l.endswith(suffix):
                return self._retrieveURL(url)
        # not a supported type
        return

    def isURL(self, s):
        s = s.lower()
        return (s.startswith("http://")
            or s.startswith("https://")
            or s.startswith("ftp://")
            or s.startswith("file://"))

    def _retrieveURL(self, url):
        "Download file into media folder and return local filename or None."
        # urllib doesn't understand percent-escaped utf8, but requires things like
        # '#' to be escaped. we don't try to unquote the incoming URL, because
        # we should only be receiving file:// urls from url mime, which is unquoted
        if url.lower().startswith("file://"):
            url = url.replace("%", "%25")
            url = url.replace("#", "%23")
        # fetch it into a temporary folder
        self.mw.progress.start(
            immediate=True, parent=self.parentWindow)
        try:
            req = urllib2.Request(url, None, {
                'User-Agent': 'Mozilla/5.0 (compatible; Anki)'})
            filecontents = urllib2.urlopen(req).read()
        except urllib2.URLError, e:
            showWarning(_("An error occurred while opening %s") % e)
            return
        finally:
            self.mw.progress.finish()
        path = unicode(urllib2.unquote(url.encode("utf8")), "utf8")
        return self.mw.col.media.writeData(path, filecontents)

    # HTML filtering
    ######################################################################

    def _filterHTML(self, html, localize=False):
        doc = BeautifulSoup(html)
        # remove implicit regular font style from outermost element
        if doc.span:
            try:
                attrs = doc.span['style'].split(";")
            except (KeyError, TypeError):
                attrs = []
            if attrs:
                new = []
                for attr in attrs:
                    sattr = attr.strip()
                    if sattr and sattr not in ("font-style: normal", "font-weight: normal"):
                        new.append(sattr)
                doc.span['style'] = ";".join(new)
            # filter out implicit formatting from webkit
        for tag in doc("span", "Apple-style-span"):
            preserve = ""
            for item in tag['style'].split(";"):
                try:
                    k, v = item.split(":")
                except ValueError:
                    continue
                if k.strip() == "color" and not v.strip() == "rgb(0, 0, 0)":
                    preserve += "color:%s;" % v
                if k.strip() in ("font-weight", "font-style"):
                    preserve += item + ";"
            if preserve:
                # preserve colour attribute, delete implicit class
                tag['style'] = preserve
                del tag['class']
            else:
                # strip completely
                tag.replaceWithChildren()
        for tag in doc("font", "Apple-style-span"):
            # strip all but colour attr from implicit font tags
            if 'color' in dict(tag.attrs):
                for attr in tag.attrs:
                    if attr != "color":
                        del tag[attr]
                    # and apple class
                del tag['class']
            else:
                # remove completely
                tag.replaceWithChildren()
            # now images
        for tag in doc("img"):
            # turn file:/// links into relative ones
            try:
                if tag['src'].lower().startswith("file://"):
                    tag['src'] = os.path.basename(tag['src'])
                if localize and self.isURL(tag['src']):
                    # convert remote image links to local ones
                    fname = self.urlToFile(tag['src'])
                    if fname:
                        tag['src'] = fname
            except KeyError:
                # for some bizarre reason, mnemosyne removes src elements
                # from missing media
                pass
                # strip all other attributes, including implicit max-width
            for attr, val in tag.attrs:
                if attr != "src":
                    del tag[attr]
            # strip superfluous elements
        for elem in "html", "head", "body", "meta":
            for tag in doc(elem):
                tag.replaceWithChildren()
        html = unicode(doc)
        return html

    # Advanced menu
    ######################################################################

    def onAdvanced(self):
        m = QMenu(self.mw)
        a = m.addAction(_("LaTeX"))
        a.setShortcut(QKeySequence("Ctrl+T, T"))
        a.connect(a, SIGNAL("triggered()"), self.insertLatex)
        a = m.addAction(_("LaTeX equation"))
        a.setShortcut(QKeySequence("Ctrl+T, E"))
        a.connect(a, SIGNAL("triggered()"), self.insertLatexEqn)
        a = m.addAction(_("LaTeX math env."))
        a.setShortcut(QKeySequence("Ctrl+T, M"))
        a.connect(a, SIGNAL("triggered()"), self.insertLatexMathEnv)
        a = m.addAction(_("Edit HTML"))
        a.setShortcut(QKeySequence("Ctrl+Shift+X"))
        a.connect(a, SIGNAL("triggered()"), self.onHtmlEdit)
        m.exec_(QCursor.pos())

    # LaTeX
    ######################################################################

    def insertLatex(self):
        self.web.eval("wrap('[latex]', '[/latex]');")

    def insertLatexEqn(self):
        self.web.eval("wrap('[$]', '[/$]');")

    def insertLatexMathEnv(self):
        self.web.eval("wrap('[$$]', '[/$$]');")

    # Keyboard layout
    ######################################################################

    def setupKeyboard(self):
        if isWin and self.mw.pm.profile['preserveKeyboard']:
            a = ctypes.windll.user32.ActivateKeyboardLayout
            a.restype = ctypes.c_void_p
            a.argtypes = [ctypes.c_void_p, ctypes.c_uint]
            g = ctypes.windll.user32.GetKeyboardLayout
            g.restype = ctypes.c_void_p
            g.argtypes = [ctypes.c_uint]
        else:
            a = g = None
        self.activateKeyboard = a
        self.getKeyboard = g

    def updateKeyboard(self):
        self.keyboardLayouts = {}

    def saveKeyboard(self):
        if not self.getKeyboard:
            return
        self.keyboardLayouts[self.currentField] = self.getKeyboard(0)

    def restoreKeyboard(self):
        if not self.getKeyboard:
            return
        if self.currentField in self.keyboardLayouts:
            self.activateKeyboard(self.keyboardLayouts[self.currentField], 0)

# Pasting, drag & drop, and keyboard layouts
######################################################################

class EditorWebView(AnkiWebView):

    def __init__(self, parent, editor):
        AnkiWebView.__init__(self)
        self.editor = editor
        self.strip = self.editor.mw.pm.profile['stripHTML']

    def keyPressEvent(self, evt):
        if evt.matches(QKeySequence.Paste):
            self.onPaste()
            return evt.accept()
        elif evt.matches(QKeySequence.Copy):
            self.onCopy()
            return evt.accept()
        elif evt.matches(QKeySequence.Cut):
            self.onCut()
            return evt.accept()
        QWebView.keyPressEvent(self, evt)

    def onCut(self):
        self.triggerPageAction(QWebPage.Cut)
        self._flagAnkiText()

    def onCopy(self):
        self.triggerPageAction(QWebPage.Copy)
        self._flagAnkiText()

    def onPaste(self):
        mime = self.mungeClip()
        self.triggerPageAction(QWebPage.Paste)
        self.restoreClip()

    def mouseReleaseEvent(self, evt):
        if not isMac and not isWin and evt.button() == Qt.MidButton:
            # middle click on x11; munge the clipboard before standard
            # handling
            mime = self.mungeClip(mode=QClipboard.Selection)
            AnkiWebView.mouseReleaseEvent(self, evt)
            self.restoreClip(mode=QClipboard.Selection)
        else:
            AnkiWebView.mouseReleaseEvent(self, evt)

    def focusInEvent(self, evt):
        window = False
        if evt.reason() in (Qt.ActiveWindowFocusReason, Qt.PopupFocusReason):
            # editor area got focus again; need to tell js not to adjust cursor
            self.eval("mouseDown++;")
            window = True
        AnkiWebView.focusInEvent(self, evt)
        if evt.reason() == Qt.TabFocusReason:
            self.eval("focusField(0);")
        elif evt.reason() == Qt.BacktabFocusReason:
            n = len(self.editor.note.fields) - 1
            self.eval("focusField(%d);" % n)
        elif window:
            self.eval("mouseDown--;")

    def dropEvent(self, evt):
        oldmime = evt.mimeData()
        # coming from this program?
        if evt.source():
            if oldmime.hasHtml():
                mime = QMimeData()
                mime.setHtml(self.editor._filterHTML(oldmime.html()))
            else:
                # old qt on linux won't give us html when dragging an image;
                # in that case just do the default action (which is to ignore
                # the drag)
                return AnkiWebView.dropEvent(self, evt)
        else:
            mime = self._processMime(oldmime)
        # create a new event with the new mime data and run it
        new = QDropEvent(evt.pos(), evt.possibleActions(), mime,
                         evt.mouseButtons(), evt.keyboardModifiers())
        evt.accept()
        QWebView.dropEvent(self, new)
        # tell the drop target to take focus so the drop contents are saved
        self.eval("dropTarget.focus();")
        self.setFocus()

    def mungeClip(self, mode=QClipboard.Clipboard):
        clip = self.editor.mw.app.clipboard()
        mime = clip.mimeData(mode=mode)
        self.saveClip(mode=mode)
        mime = self._processMime(mime)
        clip.setMimeData(mime, mode=mode)
        return mime

    def restoreClip(self, mode=QClipboard.Clipboard):
        clip = self.editor.mw.app.clipboard()
        clip.setMimeData(self.savedClip, mode=mode)

    def saveClip(self, mode):
        # we don't own the clipboard object, so we need to copy it or we'll crash
        mime = self.editor.mw.app.clipboard().mimeData(mode=mode)
        n = QMimeData()
        if mime.hasText():
            n.setText(mime.text())
        if mime.hasHtml():
            n.setHtml(mime.html())
        if mime.hasUrls():
            n.setUrls(mime.urls())
        if mime.hasImage():
            n.setImageData(mime.imageData())
        self.savedClip = n

    def _processMime(self, mime):
        # print "html=%s image=%s urls=%s txt=%s" % (
        #     mime.hasHtml(), mime.hasImage(), mime.hasUrls(), mime.hasText())
        # print "html", mime.html()
        # print "urls", mime.urls()
        # print "text", mime.text()
        if mime.hasHtml():
            return self._processHtml(mime)
        elif mime.hasUrls():
            return self._processUrls(mime)
        elif mime.hasText():
            return self._processText(mime)
        elif mime.hasImage():
            return self._processImage(mime)
        else:
            # nothing
            return QMimeData()

    # when user is dragging a file from a file manager on any platform, the
    # url type should be set, and it is not URL-encoded. on a mac no text type
    # is returned, and on windows the text type is not returned in cases like
    # "foo's bar.jpg"
    def _processUrls(self, mime):
        url = mime.urls()[0].toString()
        # chrome likes to give us the URL twice with a \n
        url = url.splitlines()[0]
        mime = QMimeData()
        link = self.editor.urlToLink(url)
        if link:
            mime.setHtml(link)
        else:
            mime.setText(url)
        return mime

    # if the user has used 'copy link location' in the browser, the clipboard
    # will contain the URL as text, and no URLs or HTML. the URL will already
    # be URL-encoded, and shouldn't be a file:// url unless they're browsing
    # locally, which we don't support
    def _processText(self, mime):
        txt = unicode(mime.text())
        html = None
        # if the user is pasting an image or sound link, convert it to local
        if self.editor.isURL(txt):
            txt = txt.split("\r\n")[0]
            html = self.editor.urlToLink(txt)
        new = QMimeData()
        if html:
            new.setHtml(html)
        else:
            new.setText(txt)
        return new

    def _processHtml(self, mime):
        html = mime.html()
        newMime = QMimeData()
        if self.strip and not html.startswith("<!--anki-->"):
            # special case for google images: if after stripping there's no text
            # and there are image links, we'll paste those as html instead
            if not stripHTML(html).strip():
                newHtml = ""
                mid = self.editor.note.mid
                for url in self.editor.mw.col.media.filesInStr(
                    mid, html, includeRemote=True):
                    newHtml += self.editor.urlToLink(url)
                if not newHtml and mime.hasImage():
                    return self._processImage(mime)
                newMime.setHtml(newHtml)
            else:
                # use .text() if available so newlines are preserved; otherwise strip
                if mime.hasText():
                    return self._processText(mime)
                else:
                    newMime.setText(stripHTML(mime.text()))
        else:
            if html.startswith("<!--anki-->"):
                html = html[11:]
            # no html stripping
            html = self.editor._filterHTML(html, localize=True)
            newMime.setHtml(html)
        return newMime

    def _processImage(self, mime):
        im = QImage(mime.imageData())
        uname = namedtmp("paste-%d" % im.cacheKey())
        if self.editor.mw.pm.profile.get("pastePNG", False):
            ext = ".png"
            im.save(uname+ext, None, 50)
        else:
            ext = ".jpg"
            im.save(uname+ext, None, 80)
        # invalid image?
        if not os.path.exists(uname+ext):
            return QMimeData()
        mime = QMimeData()
        mime.setHtml(self.editor._addMedia(uname+ext))
        return mime

    def _flagAnkiText(self):
        # add a comment in the clipboard html so we can tell text is copied
        # from us and doesn't need to be stripped
        clip = self.editor.mw.app.clipboard()
        mime = clip.mimeData()
        if not mime.hasHtml():
            return
        html = mime.html()
        mime.setHtml("<!--anki-->" + mime.html())

    def contextMenuEvent(self, evt):
        m = QMenu(self)
        a = m.addAction(_("Cut"))
        a.connect(a, SIGNAL("triggered()"), self.onCut)
        a = m.addAction(_("Copy"))
        a.connect(a, SIGNAL("triggered()"), self.onCopy)
        a = m.addAction(_("Paste"))
        a.connect(a, SIGNAL("triggered()"), self.onPaste)
        runHook("EditorWebView.contextMenuEvent", self, m)
        m.popup(QCursor.pos())
