"""
This module defines the port forwarding widget.


Copyright (c) 2023 Proton AG

This file is part of Proton VPN.

Proton VPN is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Proton VPN is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with ProtonVPN.  If not, see <https://www.gnu.org/licenses/>.
"""
from __future__ import annotations
from pathlib import Path
from typing import List, Optional
from gi.repository import Gdk, GLib, GObject
from proton.vpn.app.gtk import Gtk
from proton.vpn.app.gtk.assets import icons
from proton.vpn.connection import states

from proton.vpn.app.gtk.widgets.main.notifications import Notifications


class PortForwardRevealer(Gtk.Revealer):  # pylint: disable=too-few-public-methods
    """The container that has all PF widgets and reveals on demand."""
    def __init__(self,
                 notifications: Notifications,
                 port_forward_widget: Optional["PortForwardWidget"] = None):
        super().__init__()
        self._port_forward_widget = \
            port_forward_widget or PortForwardWidget(notifications)
        self.set_child(self._port_forward_widget)
        self._port_forward_widget.connect(
            "update-visibility", self._on_update_port_forwarding_visibility
        )

    def on_new_state(self, connection_state: states.State):
        """Proxy method that relays connection state changes to PF widget."""
        self._port_forward_widget.on_new_state(connection_state)

    def _on_update_port_forwarding_visibility(self, _: PortForwardWidget, display_child: bool):
        self.set_reveal_child(display_child)


class PortForwardWidget(Gtk.Box):
    """Widgets handles the display and interactivity to copy por to clipboard."""
    ACTIVE_PORT_LABEL = "Active port:"
    TOOLTIP_LABEL = "Copy port number"

    def __init__(
            self, notifications: Notifications, clipboard: Optional[Gdk.Clipboard] = None,
            forwarded_port: Optional[int] = None
    ):
        super().__init__(orientation=Gtk.Orientation.HORIZONTAL)
        self.set_name("port-forwarding-widget")
        self._notifications = notifications
        self._clipboard = (
            clipboard or Gdk.Display.get_default().get_clipboard()
        )
        self._current_forwarded_port = forwarded_port
        self._pending_sources: List[int] = []
        self._build_ui()
        self.connect("destroy", self._on_destroy)

    @GObject.Signal(name="update-visibility", arg_types=(bool,))
    def update_visibility(self, display_child: bool):
        """
        Signal emitted when the UI should be hidden or not.
        :param display_child: whether PF should be displayed or not.
        """

    def _build_ui(self):
        self.set_halign(Gtk.Align.START)

        active_port_label = Gtk.Label(label=self.ACTIVE_PORT_LABEL)
        active_port_label.add_css_class("dim-label")

        self._port_forward_label: Gtk.Label = Gtk.Label(label="")
        self._port_forward_label.add_css_class("dim-label")

        copy_pixbuf = icons.get(Path("copy.svg"), width=16, height=16)
        copy_icon = Gtk.Image.new_from_paintable(Gdk.Texture.new_for_pixbuf(copy_pixbuf))
        copy_icon.set_size_request(copy_pixbuf.get_width(), copy_pixbuf.get_height())

        button_content = Gtk.Box(orientation=Gtk.Orientation.HORIZONTAL, spacing=3)
        button_content.append(self._port_forward_label)
        button_content.append(copy_icon)

        self._copy_button = Gtk.Button()
        self._copy_button.set_has_frame(False)
        self._copy_button.set_child(button_content)
        self._copy_button.set_cursor(Gdk.Cursor.new_from_name("pointer", None))
        self._copy_button.connect("clicked", self._on_button_press)

        self._copied_popover = Gtk.Popover()
        self._copied_popover.set_child(Gtk.Label(label="Copied!"))
        self._copied_popover.set_autohide(False)
        self._copied_popover.set_has_arrow(False)
        self._copied_popover.set_parent(self._copy_button)

        self.set_spacing(3)
        self.append(active_port_label)
        self.append(self._copy_button)

    def on_new_state(self, connection_state: states.State):
        """Receives new connection state and emits a signal
        of whether it should be hidden or not."""
        self._update_visibility(
            connection_state.forwarded_port,
            reveal_child=isinstance(connection_state, states.Connected)
        )

        top_level = self._port_forward_label.get_root()
        is_focus = True

        # We need to check that the top level widget is indeed the main window
        # because when shutting down the app this widget could process events
        # after the main window is already closed.
        if isinstance(top_level, Gtk.Window):
            is_focus = top_level.is_active()

        new_port = connection_state.forwarded_port
        if new_port and (new_port != self._current_forwarded_port):
            if not is_focus:
                self._notifications.show_gnome_notification(
                    title="Port forwarding",
                    description=f"Active port is {new_port}"
                )

        self._current_forwarded_port = new_port

    def _update_visibility(self, forwarded_port: Optional[int], reveal_child: bool):
        if forwarded_port is None:
            self.emit("update-visibility", False)
            return

        self.emit("update-visibility", reveal_child)
        self.set_port_forward_label(forwarded_port)

    def _on_destroy(self, _):
        self._copied_popover.unparent()
        for source_id in self._pending_sources:
            GLib.source_remove(source_id)
        self._pending_sources.clear()

    def _on_button_press(self, _: "PortForwardWidget"):
        port_to_be_copied_to_clipboard = self._port_forward_label.get_label()
        value = GObject.Value(GObject.TYPE_STRING, port_to_be_copied_to_clipboard)
        self._clipboard.set(value)
        if isinstance(self.get_root(), Gtk.Window):
            self._copied_popover.popup()
            for source_id in self._pending_sources:
                GLib.source_remove(source_id)
            self._pending_sources.clear()
            self._pending_sources.append(
                GLib.timeout_add(1500, self._copied_popover.popdown)
            )

    def click_copy_button(self):
        """Simulates a click on the copy button."""
        self._copy_button.emit("clicked")

    def set_port_forward_label(self, new_port: int):
        """Helper method to set port forward label."""
        self._port_forward_label.set_label(str(new_port))
