/*
Copyright 2022 Matrix.org Foundation C.I.C.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

import React, { useCallback, useEffect, useState } from "react";
import { useHistory } from "react-router-dom";
import { GroupCall, GroupCallState } from "matrix-js-sdk/src/webrtc/groupCall";
import { MatrixClient } from "matrix-js-sdk/src/client";

import type { IWidgetApiRequest } from "matrix-widget-api";
import { widget, ElementWidgetActions, JoinCallData } from "../widget";
import { useGroupCall } from "./useGroupCall";
import { ErrorView, FullScreenView } from "../FullScreenView";
import { LobbyView } from "./LobbyView";
import { InCallView } from "./InCallView";
import { PTTCallView } from "./PTTCallView";
import { CallEndedView } from "./CallEndedView";
import { useRoomAvatar } from "./useRoomAvatar";
import { useSentryGroupCallHandler } from "./useSentryGroupCallHandler";
import { useLocationNavigation } from "../useLocationNavigation";
import { useMediaHandler } from "../settings/useMediaHandler";

declare global {
  interface Window {
    groupCall?: GroupCall;
  }
}

interface Props {
  client: MatrixClient;
  isPasswordlessUser: boolean;
  isEmbedded: boolean;
  preload: boolean;
  hideHeader: boolean;
  roomIdOrAlias: string;
  groupCall: GroupCall;
}

export function GroupCallView({
  client,
  isPasswordlessUser,
  isEmbedded,
  preload,
  hideHeader,
  roomIdOrAlias,
  groupCall,
}: Props) {
  const {
    state,
    error,
    activeSpeaker,
    userMediaFeeds,
    microphoneMuted,
    localVideoMuted,
    localCallFeed,
    initLocalCallFeed,
    enter,
    leave,
    toggleLocalVideoMuted,
    toggleMicrophoneMuted,
    toggleScreensharing,
    requestingScreenshare,
    isScreensharing,
    localScreenshareFeed,
    screenshareFeeds,
    participants,
    unencryptedEventsFromUsers,
  } = useGroupCall(groupCall);

  const { setAudioInput, setVideoInput } = useMediaHandler();

  const avatarUrl = useRoomAvatar(groupCall.room);

  useEffect(() => {
    window.groupCall = groupCall;
    return () => {
      delete window.groupCall;
    };
  }, [groupCall]);

  useEffect(() => {
    if (widget && preload) {
      // In preload mode, wait for a join action before entering
      const onJoin = async (ev: CustomEvent<IWidgetApiRequest>) => {
        const { audioInput, videoInput } = ev.detail
          .data as unknown as JoinCallData;
        if (audioInput !== null) setAudioInput(audioInput);
        if (videoInput !== null) setVideoInput(videoInput);
        await Promise.all([
          groupCall.setMicrophoneMuted(audioInput === null),
          groupCall.setLocalVideoMuted(videoInput === null),
        ]);

        await groupCall.enter();
        await Promise.all([
          widget.api.setAlwaysOnScreen(true),
          widget.api.transport.reply(ev.detail, {}),
        ]);
      };

      widget.lazyActions.on(ElementWidgetActions.JoinCall, onJoin);
      return () => {
        widget.lazyActions.off(ElementWidgetActions.JoinCall, onJoin);
      };
    }
  }, [groupCall, preload, setAudioInput, setVideoInput]);

  useEffect(() => {
    if (isEmbedded && !preload) {
      // In embedded mode, bypass the lobby and just enter the call straight away
      groupCall.enter();
    }
  }, [groupCall, isEmbedded, preload]);

  useSentryGroupCallHandler(groupCall);

  useLocationNavigation(requestingScreenshare);

  const [left, setLeft] = useState(false);
  const history = useHistory();

  const onLeave = useCallback(() => {
    leave();
    if (widget) {
      widget.api.transport.send(ElementWidgetActions.HangupCall, {});
      widget.api.setAlwaysOnScreen(false);
    }

    if (isPasswordlessUser) {
      setLeft(true);
    } else if (!isEmbedded) {
      history.push("/");
    }
  }, [leave, isPasswordlessUser, isEmbedded, history]);

  useEffect(() => {
    if (widget && state === GroupCallState.Entered) {
      const onHangup = async (ev: CustomEvent<IWidgetApiRequest>) => {
        leave();
        await widget.api.transport.reply(ev.detail, {});
      };
      widget.lazyActions.once(ElementWidgetActions.HangupCall, onHangup);
      return () => {
        widget.lazyActions.off(ElementWidgetActions.HangupCall, onHangup);
      };
    }
  }, [groupCall, state, leave]);

  if (error) {
    return <ErrorView error={error} />;
  } else if (state === GroupCallState.Entered) {
    if (groupCall.isPtt) {
      return (
        <PTTCallView
          client={client}
          roomIdOrAlias={roomIdOrAlias}
          roomName={groupCall.room.name}
          avatarUrl={avatarUrl}
          groupCall={groupCall}
          participants={participants}
          userMediaFeeds={userMediaFeeds}
          onLeave={onLeave}
          isEmbedded={isEmbedded}
          hideHeader={hideHeader}
        />
      );
    } else {
      return (
        <InCallView
          groupCall={groupCall}
          client={client}
          roomName={groupCall.room.name}
          avatarUrl={avatarUrl}
          microphoneMuted={microphoneMuted}
          localVideoMuted={localVideoMuted}
          toggleLocalVideoMuted={toggleLocalVideoMuted}
          toggleMicrophoneMuted={toggleMicrophoneMuted}
          userMediaFeeds={userMediaFeeds}
          activeSpeaker={activeSpeaker}
          onLeave={onLeave}
          toggleScreensharing={toggleScreensharing}
          isScreensharing={isScreensharing}
          localScreenshareFeed={localScreenshareFeed}
          screenshareFeeds={screenshareFeeds}
          roomIdOrAlias={roomIdOrAlias}
          unencryptedEventsFromUsers={unencryptedEventsFromUsers}
          hideHeader={hideHeader}
        />
      );
    }
  } else if (state === GroupCallState.Entering) {
    return (
      <FullScreenView>
        <h1>Entering room...</h1>
      </FullScreenView>
    );
  } else if (left) {
    return <CallEndedView client={client} />;
  } else if (preload) {
    return null;
  } else if (isEmbedded) {
    return (
      <FullScreenView>
        <h1>Loading room...</h1>
      </FullScreenView>
    );
  } else {
    return (
      <LobbyView
        client={client}
        groupCall={groupCall}
        roomName={groupCall.room.name}
        avatarUrl={avatarUrl}
        state={state}
        onInitLocalCallFeed={initLocalCallFeed}
        localCallFeed={localCallFeed}
        onEnter={enter}
        microphoneMuted={microphoneMuted}
        localVideoMuted={localVideoMuted}
        toggleLocalVideoMuted={toggleLocalVideoMuted}
        toggleMicrophoneMuted={toggleMicrophoneMuted}
        roomIdOrAlias={roomIdOrAlias}
        isEmbedded={isEmbedded}
        hideHeader={hideHeader}
      />
    );
  }
}