# Hook to main, and extend channel tabs
    def __init__(self, parent):
        self.parent = parent
        parent.hooks["init"].append(self.add_dnd)
        conf.add_plugin_defaults(self.meta, self.module)



    # Attach drag and drop handlers to each channels´ station TreeView
    def add_dnd(self, parent):

        # visit each module
        for cn,module in parent.channels.items():
            w = module.gtk_list
            # bind SOURCE events
            w.enable_model_drag_source(gtk.gdk.BUTTON1_MASK, self.drag_types, gtk.gdk.ACTION_DEFAULT|gtk.gdk.ACTION_COPY)
            w.connect('drag-begin', self.begin)
            w.connect('drag-data-get', self.data_get)
            # bind DESTINATION events
            w.enable_model_drag_dest(self.drag_types, gtk.gdk.ACTION_DEFAULT|gtk.gdk.ACTION_COPY)
            w.connect('drag-drop', self.drop)
            w.connect('drag-data-received', self.data_received)
            
        # register bookmarks category as destination too
        w = parent.bookmarks.gtk_cat
        w.enable_model_drag_dest([self.drag_types[0]], gtk.gdk.ACTION_DEFAULT|gtk.gdk.ACTION_MOVE)
        w.connect('drag-data-received', self.data_received)
        



    # -- SOURCE, drag'n'drop from ST2 to elsewhere --

    # Starting to drag a row
    def begin(self, widget, context):
        log.DND("source→out: begin-drag, store current row")
        self.row = self.treelist_row()
        self.buf = {}
        if "set_icon_stock" in dir(context):
            uikit.do(context.set_icon_stock, gtk.STOCK_ADD, 16, 16)
        return "url" in self.row

    # Keep currently selected row when source dragging starts
    def treelist_row(self):
        cn = self.parent.channel()
        row = copy.copy(cn.row())
        row.setdefault("format", cn.audioformat)
        row.setdefault("listformat", cn.listformat)
        row.setdefault("url", row.get("homepage"))
        row.update({"_origin": [cn.module, cn.current, cn.rowno()]}) # internal: origin channel+genre+rowid
        return row
    
    # Target window/app requests data for offered drop
    def data_get(self, widget, context, selection, info, time):
        log.DND("source→out: data-get, send and convert to requested target type:", info, selection.get_target())
        # Return prepared data
        func, data = self.export_row(info, self.row)
        log.DND("data==", func, data)
        if func.find("text") >= 0:
            # Yay for trial and error. Nay for docs. PyGtks selection.set_text() doesn't
            # actually work unless the requested target type is an Atom. Therefore "STRING".
            selection.set("STRING", 8, data)
            # Neither gtk.gdk.TARGET_STRING nor selection.get_target() satisfy Gtk3 however
        if func.find("uris") >= 0:
            selection.set_uris(data)
        return True

    # Handles the conversion from the stored .row to the desired selection data
    def export_row(self, info, r):

            #buf = 'uris', urls
            buf = 'text', urls[0]
        # Text sources are assumed to understand the literal URL or expect a description block
        elif info >= 5:
            buf = 'text', "{url}\n# Title: {title}\n# Homepage: {homepage}\n\n".format(**r)
        # Create temporary PLS file, because "text/uri-list" is widely misunderstood and just implemented for file:// IRLs
        else:
            title = re.sub("[^\w-]+", "_", r["title"]).strip()
            tmpfn = "{}/{}.{}".format(conf.tmp, title, conf.dnd_format)
            log.DND("tmpfn", tmpfn)
            cnv.file(rows=[r], dest=conf.dnd_format, fn=tmpfn)
            if info == 4:
                buf = 'uris', ["file://{}".format(tmpfn)]
            else:
                buf = 'text', tmpfn

        # Keep in type request buffer
        self.buf[info] = buf
        return buf