added simple telnet client

app/ui/app_menu.ui

@@ -143,8 +143,10 @@
           <attribute name="label" translatable="yes">Backups</attribute>
           <attribute name="action">app.on_backup_tool_show</attribute>
         </item>
-      </section>
-      <section id="telnet_section">
+        <item>
+          <attribute name="label" translatable="yes">Telnet</attribute>
+          <attribute name="action">app.on_telnet_show</attribute>
+        </item>
       </section>
     </submenu>
     <submenu>
@@ -327,8 +329,10 @@
           <attribute name="label" translatable="yes">Backups</attribute>
           <attribute name="action">app.on_backup_tool_show</attribute>
         </item>
-      </section>
-      <section id="telnet_section">
+        <item>
+          <attribute name="label" translatable="yes">Telnet</attribute>
+          <attribute name="action">app.on_telnet_show</attribute>
+        </item>
       </section>
     </submenu>
     <submenu>

app/ui/main.glade

@@ -3255,6 +3255,21 @@ Author: Dmitriy Yefremov
               </packing>
             </child>
           </object>
+          <packing>
+            <property name="expand">True</property>
+            <property name="fill">True</property>
+            <property name="position">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkBox" id="telnet_box">
+            <property name="can_focus">False</property>
+            <property name="orientation">vertical</property>
+            <signal name="realize" handler="on_telnet_relize" swapped="no"/>
+            <child>
+              <placeholder/>
+            </child>
+          </object>
           <packing>
             <property name="expand">True</property>
             <property name="fill">True</property>

app/ui/main.py

@@ -52,6 +52,7 @@ from app.ui.control import ControlTool, EpgTool, TimerTool, RecordingsTool
 from app.ui.epg import EpgDialog
 from app.ui.ftp import FtpClientBox
 from app.ui.playback import PlayerBox
+from app.ui.telnet import TelnetClient
 from app.ui.transmitter import LinksTransmitter
 from .backup import BackupDialog, backup_data, clear_data_path
 from .dialogs import show_dialog, DialogType, get_chooser_dialog, WaitDialog, get_message, get_builder
@@ -193,6 +194,7 @@ class Application(Gtk.Application):
                     "on_recordings_realize": self.on_recordings_realize,
                     "on_control_realize": self.on_control_realize,
                     "on_ftp_realize": self.on_ftp_realize,
+                    "on_telnet_relize": self.on_telnet_relize,
                     "on_visible_page": self.on_visible_page,
                     "on_data_paned_realize": self.init_main_paned_position}
 
@@ -384,6 +386,7 @@ class Application(Gtk.Application):
         self._stack_recordings_box = builder.get_object("recordings_box")
         self._stack_ftp_box = builder.get_object("ftp_box")
         self._stack_control_box = builder.get_object("control_box")
+        self._telnet_box = builder.get_object("telnet_box")
         self.connect("change-page", self.on_page_change)
         # Header bar.
         profile_box = builder.get_object("profile_combo_box")
@@ -460,6 +463,7 @@ class Application(Gtk.Application):
         self.set_action("on_backup_tool_show", self.on_backup_tool_show)
         self.set_action("on_about_app", self.on_about_app)
         self.set_action("on_close_app", self.on_close_app)
+        self.set_state_action("on_telnet_show", self.on_telnet_show, False)
         # Filter.
         filter_action = Gio.SimpleAction.new("filter", None)
         filter_action.connect("activate", lambda a, v: self.emit("filter-toggled", None))
@@ -539,6 +543,7 @@ class Application(Gtk.Application):
         self.set_accels_for_action("app.on_locked", ["<primary>l"])
         self.set_accels_for_action("app.on_close_app", ["<primary>q"])
         self.set_accels_for_action("app.on_edit", ["<primary>e"])
+        self.set_accels_for_action("app.on_telnet_show", ["<primary>t"])
         self.set_accels_for_action("win.filter", ["<shift><primary>f"])
 
     def do_activate(self):
@@ -782,10 +787,14 @@ class Application(Gtk.Application):
         self._ftp_client = FtpClientBox(self, self._settings)
         box.pack_start(self._ftp_client, True, True, 0)
 
-    def on_control_realize(self, box: Gtk.HBox):
+    def on_control_realize(self, box):
         self._control_tool = ControlTool(self, self._http_api, self._settings)
         box.pack_start(self._control_tool, True, True, 0)
 
+    def on_telnet_relize(self, box):
+        telnet_tool = TelnetClient(self, self._settings)
+        box.pack_start(telnet_tool, True, True, 0)
+
     def on_visible_page(self, stack, param):
         self._page = Page(stack.get_visible_child_name())
         self._fav_paned.set_visible(self._page in self._fav_pages)
@@ -2646,6 +2655,12 @@ class Application(Gtk.Application):
         """ Shows backup tool dialog """
         BackupDialog(self._main_window, self._settings, self.open_data).show()
 
+    # ***************** Telnet  ******************** #
+
+    def on_telnet_show(self, action, value=False):
+        action.set_state(value)
+        GLib.idle_add(self._telnet_box.set_visible, value)
+
     # ************************* Streams ***************************** #
 
     def on_play_stream(self, item=None):

app/ui/telnet.glade

@@ -0,0 +1,183 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Generated with glade 3.22.2 
+
+The MIT License (MIT)
+
+Copyright (c) 2018-2020 Dmitriy Yefremov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+Author: Dmitriy Yefremov
+
+-->
+<interface domain="demon-editor">
+  <requires lib="gtk+" version="3.16"/>
+  <!-- interface-license-type mit -->
+  <!-- interface-name DemonEditor -->
+  <!-- interface-copyright 2018-2021 Dmitriy Yefremov -->
+  <!-- interface-authors Dmitriy Yefremov -->
+  <object class="GtkTextTagTable" id="tag_table">
+    <child type="tag">
+      <object class="GtkTextTag" id="end_tag">
+        <property name="font">Normal</property>
+        <property name="editable">False</property>
+      </object>
+    </child>
+  </object>
+  <object class="GtkTextBuffer" id="text_buffer">
+    <property name="tag_table">tag_table</property>
+  </object>
+  <object class="GtkFrame" id="telnet_frame">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="margin_left">5</property>
+    <property name="margin_right">5</property>
+    <property name="margin_top">5</property>
+    <property name="margin_bottom">5</property>
+    <property name="label_xalign">0.49000000953674316</property>
+    <property name="shadow_type">in</property>
+    <child>
+      <object class="GtkBox" id="telnet_main_box">
+        <property name="width_request">480</property>
+        <property name="height_request">180</property>
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="margin_left">5</property>
+        <property name="margin_right">5</property>
+        <property name="margin_bottom">5</property>
+        <property name="orientation">vertical</property>
+        <property name="spacing">5</property>
+        <child>
+          <object class="GtkBox" id="commands_entry">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="margin_left">5</property>
+            <property name="margin_right">5</property>
+            <property name="margin_bottom">2</property>
+            <property name="spacing">5</property>
+            <child>
+              <object class="GtkButton" id="connect_button">
+                <property name="visible">True</property>
+                <property name="can_focus">True</property>
+                <property name="receives_default">True</property>
+                <property name="tooltip_text" translatable="yes">Connect</property>
+                <signal name="clicked" handler="on_connect" swapped="no"/>
+                <child>
+                  <object class="GtkImage" id="connect_button_image">
+                    <property name="visible">True</property>
+                    <property name="can_focus">False</property>
+                    <property name="stock">gtk-connect</property>
+                  </object>
+                </child>
+              </object>
+              <packing>
+                <property name="expand">False</property>
+                <property name="fill">True</property>
+                <property name="position">0</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkButton" id="disconnect_button">
+                <property name="can_focus">True</property>
+                <property name="receives_default">True</property>
+                <property name="tooltip_text" translatable="yes">Disconnect</property>
+                <signal name="clicked" handler="on_disconnect" swapped="no"/>
+                <child>
+                  <object class="GtkImage" id="disconnect_button_image">
+                    <property name="visible">True</property>
+                    <property name="can_focus">False</property>
+                    <property name="stock">gtk-disconnect</property>
+                  </object>
+                </child>
+              </object>
+              <packing>
+                <property name="expand">False</property>
+                <property name="fill">True</property>
+                <property name="position">1</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkButton" id="clear_button">
+                <property name="visible">True</property>
+                <property name="can_focus">True</property>
+                <property name="receives_default">True</property>
+                <property name="tooltip_text" translatable="yes">Clear</property>
+                <property name="halign">center</property>
+                <property name="valign">center</property>
+                <signal name="clicked" handler="on_clear" swapped="no"/>
+                <child>
+                  <object class="GtkImage" id="clear_button_image">
+                    <property name="visible">True</property>
+                    <property name="can_focus">False</property>
+                    <property name="stock">gtk-clear</property>
+                  </object>
+                </child>
+              </object>
+              <packing>
+                <property name="expand">False</property>
+                <property name="fill">True</property>
+                <property name="position">2</property>
+              </packing>
+            </child>
+          </object>
+          <packing>
+            <property name="expand">False</property>
+            <property name="fill">True</property>
+            <property name="position">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkScrolledWindow" id="telnet_scrolled_window">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="shadow_type">in</property>
+            <child>
+              <object class="GtkTextView" id="text_view">
+                <property name="name">textview-large</property>
+                <property name="visible">True</property>
+                <property name="can_focus">True</property>
+                <property name="wrap_mode">char</property>
+                <property name="left_margin">5</property>
+                <property name="right_margin">5</property>
+                <property name="buffer">text_buffer</property>
+                <property name="overwrite">True</property>
+                <property name="input_hints">GTK_INPUT_HINT_WORD_COMPLETION | GTK_INPUT_HINT_NONE</property>
+                <property name="monospace">True</property>
+                <signal name="key-press-event" handler="on_view_key_press" swapped="no"/>
+                <signal name="realize" handler="on_text_view_realize" swapped="no"/>
+              </object>
+            </child>
+          </object>
+          <packing>
+            <property name="expand">True</property>
+            <property name="fill">True</property>
+            <property name="position">1</property>
+          </packing>
+        </child>
+      </object>
+    </child>
+    <child type="label">
+      <object class="GtkLabel">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="label" translatable="yes">Telnet</property>
+      </object>
+    </child>
+  </object>
+</interface>

app/ui/telnet.py

@@ -0,0 +1,224 @@
+import re
+import selectors
+import socket
+from collections import deque
+from telnetlib import Telnet
+
+from gi.repository import GLib
+
+from app.commons import run_task, run_idle, log
+from app.ui.uicommons import Gtk, Gdk, UI_RESOURCES_PATH, KeyboardKey, MOD_MASK
+
+
+class ExtTelnet(Telnet):
+
+    def __init__(self, output_callback, **kwargs):
+        super().__init__(**kwargs)
+        self._output_callback = output_callback
+
+    def interact(self):
+        """ Interaction function, emulates a very dumb telnet client. """
+        with selectors.DefaultSelector() as selector:
+            selector.register(self, selectors.EVENT_READ)
+
+            while True:
+                for key, events in selector.select():
+                    if key.fileobj is self:
+                        try:
+                            text = self.read_very_eager()
+                        except EOFError as e:
+                            msg = "\n*** Connection closed by remote host ***\n"
+                            self._output_callback(msg)
+                            log(msg)
+                            raise e
+                        else:
+                            if text:
+                                self._output_callback(text)
+
+
+class TelnetClient(Gtk.Box):
+    """ Very simple telnet client. """
+    _COLOR_PATTERN = re.compile("\x1b.*?m")  # Color info
+    _ERASING_PATTERN = re.compile("\x1b.*?K")  # Erase to right
+    _APP_MODE_PATTERN = re.compile("\x1b.*?(1h)|(1l)")  # h - on, l - off
+    _ALL_PATTERN = re.compile(r'(\x1b\[|\x9b)[0-?]*[@-~]')
+    _NOT_SUPPORTED = {"mc", "mcedit", "vi", "nano"}
+
+    def __init__(self, app, settings, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._app = app
+        self._app.connect("profile-changed", self.on_profile_changed)
+
+        self._tn = None
+        self._app_mode = False
+        self._commands = deque(maxlen=10)
+
+        self._handlers = {"on_clear": self.on_clear,
+                          "on_text_view_realize": self.on_text_view_realize,
+                          "on_view_key_press": self.on_view_key_press,
+                          "on_connect": self.on_connect,
+                          "on_disconnect": self.on_disconnect}
+
+        builder = Gtk.Builder()
+        builder.add_from_file(UI_RESOURCES_PATH + "telnet.glade")
+        builder.connect_signals(self._handlers)
+
+        self._text_view = builder.get_object("text_view")
+        self._buf = builder.get_object("text_buffer")
+        self._end_tag = builder.get_object("end_tag")
+        self._connect_button = builder.get_object("connect_button")
+        self._connect_button.bind_property("visible", builder.get_object("disconnect_button"), "visible", 4)
+
+        main_frame = builder.get_object("telnet_frame")
+        provider = Gtk.CssProvider()
+        provider.load_from_path(UI_RESOURCES_PATH + "style.css")
+        main_frame.get_style_context().add_provider(provider, Gtk.STYLE_PROVIDER_PRIORITY_USER)
+
+        self.pack_start(main_frame, True, True, 0)
+        self.show()
+
+    def on_profile_changed(self, app, data):
+        self.on_clear()
+        self.on_disconnect()
+        self.on_connect()
+
+    def on_text_view_realize(self, view):
+        self.on_connect()
+
+    @run_task
+    def on_connect(self, item=None):
+        try:
+            GLib.idle_add(self._connect_button.set_visible, False)
+            settings = self._app.app_settings
+            user, password, timeout = settings.user, settings.password, settings.telnet_timeout
+            self._tn = ExtTelnet(self.append_output, host=settings.host, port=settings.telnet_port, timeout=timeout)
+
+            if user != "":
+                self._tn.read_until(b"login: ")
+                self._tn.write(user.encode("utf-8") + b"\n")
+            if password != "":
+                self._tn.read_until(b"Password: ")
+                self._tn.write(password.encode("utf-8") + b"\n")
+
+            self._tn.interact()
+        except (OSError, EOFError, socket.timeout, ConnectionRefusedError) as e:
+            log(f"{self.__class__.__name__}: {e}")
+            self._app.show_info_message(str(e), Gtk.MessageType.ERROR)
+        finally:
+            GLib.idle_add(self._connect_button.set_visible, True)
+
+    @run_task
+    def on_disconnect(self, item=None):
+        if self._tn:
+            GLib.idle_add(self._connect_button.set_visible, True)
+            self._tn.close()
+
+    def on_command_done(self, entry):
+        command = entry.get_text()
+        entry.set_text("")
+        if command and self._tn:
+            self._tn.write(command.encode("ascii") + b"\r")
+
+    def on_clear(self, item=None):
+        self._buf.delete(self._buf.get_start_iter(), self._buf.get_end_iter())
+
+    def on_view_key_press(self, view, event):
+        """ Handling  keystrokes on press. """
+        if event.keyval == Gdk.KEY_Return:
+            self.do_command()
+            return True
+
+        key_code = event.hardware_keycode
+        if not KeyboardKey.value_exist(key_code):
+            return
+
+        key = KeyboardKey(key_code)
+        ctrl = event.state & MOD_MASK
+        if ctrl and key is KeyboardKey.C:
+            if self._tn and self._tn.sock:
+                self._tn.write(b"\x03")  # interrupt
+
+        # Last commands navigation.
+        if key is KeyboardKey.UP:
+            self.delete_last_command()
+            if self._commands:
+                cmd = self._commands.pop()
+                self._commands.appendleft(cmd)
+                self._buf.insert_at_cursor(cmd, -1)
+            return True
+        elif key is KeyboardKey.DOWN:
+            self.delete_last_command()
+            if self._commands:
+                cmd = self._commands.popleft()
+                self._commands.append(cmd)
+                self._buf.insert_at_cursor(cmd, -1)
+            return True
+
+    def delete_last_command(self):
+        end = self._buf.get_end_iter()
+        if end.ends_tag(self._end_tag):
+            return
+
+        if end.backward_to_tag_toggle(self._end_tag):
+            self._buf.delete(self._buf.get_end_iter(), end)
+
+    def do_command(self):
+        count = self._buf.get_line_count()
+        begin = self._buf.get_iter_at_line(count)
+        end = self._buf.get_end_iter()
+        command = []
+
+        while end.backward_to_tag_toggle(self._end_tag):
+            command.append(self._buf.get_text(end, begin, False))
+            break
+        else:  # if buf is empty
+            command.append(self._buf.get_text(begin, end, False))
+
+        # To preventing duplication of the command in the buf.
+        self._buf.delete(end, begin)
+
+        if command and self._tn.sock:
+            cmd = command[0]
+            if cmd in self._NOT_SUPPORTED:
+                self._app.show_info_message(f"'{cmd}' is not supported by this client.", Gtk.MessageType.ERROR)
+            else:
+                self._tn.write(cmd.encode("ascii") + b"\r")
+                self._commands.append(cmd)
+
+    @run_idle
+    def append_output(self, txt):
+        t = txt.decode("ascii", errors="ignore")
+
+        ap = re.search(self._APP_MODE_PATTERN, t)
+        if ap:
+            on, of = ap.group(1), ap.group(2)
+            if on:
+                self._app_mode = True
+            elif of:
+                self._app_mode = False
+                self.on_clear()
+
+        t = re.sub(self._ALL_PATTERN, "", t)  # Removing [replacing] ascii escape sequences.
+
+        if self._app_mode:
+            start, end = self._buf.get_start_iter(), self._buf.get_end_iter()
+            count = self._buf.get_line_count()
+            new_lines = t.split("\r\n")
+            ext_lines = self._buf.get_text(start, end, True).split("\r\n")
+            if count < len(new_lines):
+                self._buf.set_text(re.sub(self._ERASING_PATTERN, "", t))
+            else:
+                for i, line in enumerate(new_lines):
+                    if line:
+                        ext_lines[i] = re.sub(self._ERASING_PATTERN, "", line)
+                self._buf.set_text("\r\n".join(ext_lines))
+        else:
+            self._buf.insert_at_cursor(t, -1)
+
+        insert = self._buf.get_insert()
+        self._text_view.scroll_to_mark(insert, 0.0, True, 0.0, 1.0)
+        self._buf.apply_tag(self._end_tag, self._buf.get_start_iter(), self._buf.get_end_iter())
+
+
+if __name__ == "__main__":
+    pass