import React, { forwardRef, useCallback, useEffect, useState } from 'react';
import { Dialog, Header, config, Box, Text, Button, Spinner, color } from 'folds';
import { useAtom } from 'jotai';
import { AsyncStatus, useAsyncCallback } from '../hooks/useAsyncCallback';
import { logoutClient } from '../../client/initMatrix';
import { callEmbedAtom } from '../state/callEmbed';
import { hangupCallAndWait } from '../plugins/call/hangup';
import { useMatrixClient } from '../hooks/useMatrixClient';
import { useModalStyle } from '../hooks/useModalStyle';
import { useCrossSigningActive } from '../hooks/useCrossSigning';
import { InfoCard } from './info-card';
import { ScheduledMessage } from '../state/scheduledMessages';
import { cancelScheduledMessage, fetchScheduledMessages } from '../utils/scheduledMessages';
import {
  useDeviceVerificationStatus,
  VerificationStatus,
} from '../hooks/useDeviceVerificationStatus';

/**
 * Ask Element Call to hang up and wait (bounded) until our own MatrixRTC
 * membership has actually been removed from the room, so the leave reaches
 * the homeserver before the client is stopped and the token is revoked.
 */
type LogoutDialogProps = {
  handleClose: () => void;
};
export const LogoutDialog = forwardRef<HTMLDivElement, LogoutDialogProps>(
  ({ handleClose }, ref) => {
    const mx = useMatrixClient();
    const modalStyle = useModalStyle(480);
    const hasEncryptedRoom = !!mx.getRooms().find((room) => room.hasEncryptionStateEvent());
    const crossSigningActive = useCrossSigningActive();
    const verificationStatus = useDeviceVerificationStatus(
      mx.getCrypto(),
      mx.getSafeUserId(),
      mx.getDeviceId() ?? undefined,
    );

    const [callEmbed, setCallEmbed] = useAtom(callEmbedAtom);

    // [Gitea #322] Scheduled messages live on the server and still send after
    // logout, where no client would show them. Say so, and offer to cancel.
    const [scheduled, setScheduled] = useState<ScheduledMessage[]>([]);
    useEffect(() => {
      let alive = true;
      fetchScheduledMessages(mx)
        .then((list) => alive && setScheduled(list))
        .catch(() => undefined);
      return () => {
        alive = false;
      };
    }, [mx]);

    const [logoutState, logout] = useAsyncCallback<void, Error, [boolean?]>(
      useCallback(
        async (cancelScheduled?: boolean) => {
          if (cancelScheduled) {
            await Promise.all(scheduled.map((m) => cancelScheduledMessage(mx, m.delayId)));
          }
          // [Gitea #29] Logging out mid-call must hang up first, or the MatrixRTC
          // membership (expires: 4 h) stays behind as a ghost participant and
          // everyone else sees you "in call" until it times out.
          if (callEmbed && callEmbed.joined && !callEmbed.disposed) {
            await hangupCallAndWait(mx, callEmbed);
            setCallEmbed(undefined);
          }
          await logoutClient(mx);
        },
        [mx, callEmbed, setCallEmbed, scheduled],
      ),
    );

    const ongoingLogout = logoutState.status === AsyncStatus.Loading;

    return (
      <Dialog
        id="logoutdialog-dialog-1"
        role="dialog"
        aria-modal="true"
        aria-labelledby="logoutdialog-dialog-1-title"
        tabIndex={-1}
        variant="Surface"
        ref={ref}
        style={modalStyle}
      >
        <Header
          style={{
            padding: `0 ${config.space.S200} 0 ${config.space.S400}`,
            borderBottomWidth: config.borderWidth.B300,
          }}
          variant="Surface"
          size="500"
        >
          <Box grow="Yes">
            <Text id="logoutdialog-dialog-1-title" as="h2" size="H4">
              Logout
            </Text>
          </Box>
        </Header>
        <Box style={{ padding: config.space.S400 }} direction="Column" gap="400">
          {hasEncryptedRoom &&
            (crossSigningActive ? (
              verificationStatus === VerificationStatus.Unverified && (
                <InfoCard
                  variant="Critical"
                  title="Unverified Device"
                  description="Verify your device before logging out to save your encrypted messages."
                />
              )
            ) : (
              <InfoCard
                variant="Critical"
                title="Alert"
                description="Enable device verification or export your encrypted data from settings to avoid losing access to your messages."
              />
            ))}
          {scheduled.length > 0 && (
            <InfoCard
              variant="Warning"
              title={`${scheduled.length} scheduled message${scheduled.length === 1 ? '' : 's'}`}
              description="Scheduled messages still send after you log out. Cancel them now if you don't want them sent."
            />
          )}
          <Text priority="400">You’re about to log out. Are you sure?</Text>
          {logoutState.status === AsyncStatus.Error && (
            <Text style={{ color: color.Critical.Main }} size="T300">
              Failed to logout! {logoutState.error.message}
            </Text>
          )}
          <Box direction="Column" gap="200">
            <Button
              variant="Critical"
              onClick={() => logout()}
              disabled={ongoingLogout}
              before={ongoingLogout && <Spinner variant="Critical" fill="Solid" size="200" />}
            >
              <Text size="B400">
                {scheduled.length > 0 ? 'Logout and keep scheduled messages' : 'Logout'}
              </Text>
            </Button>
            {scheduled.length > 0 && (
              <Button
                variant="Critical"
                fill="Soft"
                onClick={() => logout(true)}
                disabled={ongoingLogout}
              >
                <Text size="B400">Cancel scheduled messages and logout</Text>
              </Button>
            )}
            <Button variant="Secondary" fill="Soft" onClick={handleClose} disabled={ongoingLogout}>
              <Text size="B400">Cancel</Text>
            </Button>
          </Box>
        </Box>
      </Dialog>
    );
  },
);