import { useEffect } from 'react';
import { useAtomValue, useSetAtom, useStore } from 'jotai';
import { App } from '@capacitor/app';
import { pendingCallActionAtom } from '../state/pendingCallAction';
import { incomingCallsAtom } from '../state/incomingCalls';
import { callEmbedAtom, overLockCallAtom } from '../state/callEmbed';
import { useMatrixClient } from './useMatrixClient';
import { isNativePlatform } from '../utils/capacitor';
import { useSwitchOrStartDmCall } from './useSwitchOrStartDmCall';
import { telecomCall } from '../plugins/call/telecomCall';
import { overLockCall } from '../plugins/call/overLockCall';
import { callForegroundService } from '../plugins/call/callForegroundService';

// Consumes pending call actions emitted by the native Android push-action
// listener (see usePushNotifications.ts). Must be mounted inside CallEmbedProvider
// so useSwitchOrStartDmCall can reach the embed atom.
export const usePendingCallActionConsumer = (): void => {
  const pending = useAtomValue(pendingCallActionAtom);
  const setPending = useSetAtom(pendingCallActionAtom);
  const setIncoming = useSetAtom(incomingCallsAtom);
  const setOverLock = useSetAtom(overLockCallAtom);
  const switchOrStartDmCall = useSwitchOrStartDmCall();
  const store = useStore();
  const mx = useMatrixClient();

  useEffect(() => {
    if (!pending) return;
    if (pending.kind === 'answer') {
      const { roomId, notifEventId } = pending;
      setPending(undefined);
      // Move a ring-time Telecom session (created natively from the FCM ring,
      // Phase C) RINGING → ACTIVE. This synchronously marks the session answered
      // so the REMOVE_BY_* below — which bridges removeIncomingRing — keeps the
      // now-active session + its phoneCall FGS instead of tearing them down.
      // No-op when Telecom is off or no native ring session exists.
      telecomCall.answer(roomId).then(
        () => {
          // Clear the native ring slot (telecomRingEventId) directly. A
          // cold-start answer-from-killed ring may not be in incomingCallsAtom
          // yet, so the atom REMOVE_BY_* below would be a no-op and the slot
          // would stick ~32s (until the expiry alarm), degrading the next call
          // to notification-only (M12). answer() above set the session answered,
          // so maybeTeardownTelecomRing keeps the now-active session + its FGS.
          if (notifEventId) {
            callForegroundService.removeIncomingRing(notifEventId).catch(() => undefined);
          }
        },
        () => {
          /* best-effort — JS join below is the source of truth for media */
        }
      );
      // Close the §2.2 mic-retention window on answer-from-killed: the ring-time
      // FGS is phoneCall-only, and the microphone type is otherwise added only on
      // JoinCall (seconds later) — leaving mic AppOps unprotected under the lock in
      // between. Re-issue the FGS with the microphone type NOW. computeForegroundType
      // intersects with the RECORD_AUDIO grant natively, so this is upgrade-or-noop
      // (stays phoneCall-only if the grant is somehow missing — never throws). (M11)
      callForegroundService
        .start({ phoneCall: true, title: mx.getRoom(roomId)?.name || undefined })
        .catch(() => undefined);
      // If the user answered on a locked device, MainActivity is showing over the
      // keyguard (over_lock) — enter the full-screen over-lock call screen so the
      // rest of the app stays covered (privacy) while audio joins without unlock.
      // `left` guards a late getState() from re-showing the overlay after we've
      // already exited (join failure / unlock racing the bridge round-trip).
      let left = false;
      const leaveOverLock = () => {
        left = true;
        overLockCall.exit().then(
          () => setOverLock(false),
          () => setOverLock(false)
        );
      };
      overLockCall.getState().then(
        (s) => {
          if (!left && s.overLock) setOverLock(true);
        },
        () => undefined
      );
      const dropRing = () => {
        if (notifEventId) {
          setIncoming({ type: 'REMOVE_BY_NOTIF_ID', notifEventId });
          return;
        }
        setIncoming({ type: 'REMOVE_BY_ROOM', roomId });
      };
      switchOrStartDmCall(roomId, true /* answering an incoming ring */)
        .then(() => {
          dropRing();
          // switchOrStartDmCall resolves (not rejects) when the room isn't in the
          // store yet (cold-start answer-from-killed). With no embed the over-lock
          // screen would strand the user on a spinner, so bail out of over-lock.
          // No embed means the joined/embed-lifecycle teardowns won't run either,
          // so end the Telecom session AND stop the ring-time phoneCall FGS here
          // (both leak otherwise — H2).
          if (!store.get(callEmbedAtom)) {
            telecomCall.endCall().catch(() => undefined);
            callForegroundService.stop().catch(() => undefined);
            leaveOverLock();
          }
        })
        .catch((err: unknown) => {
          // eslint-disable-next-line no-console
          console.warn('[call] native answer switch/start failed', err);
          // Join failed after we answered the Telecom session — tear it down so
          // the phoneCall FGS + system call presence don't leak. endCall() flips
          // the native session out of "answered"; stop() ends the FGS directly
          // (the atom dropRing below is a no-op for a cold-start ring not in the
          // atom, so don't depend on it for FGS teardown — H2).
          telecomCall.endCall().catch(() => undefined);
          callForegroundService.stop().catch(() => undefined);
          leaveOverLock();
          dropRing();
        });
      return;
    }

    const { roomId, notifEventId } = pending;
    setPending(undefined);
    // Unreachable in practice: every Decline button press fires
    // CallDeclineReceiver via PendingIntent.getBroadcast,
    // so MainActivity never boots and `pushNotificationActionPerformed` never
    // fires with call_action='decline'. Nothing else queues a decline onto
    // pendingCallActionAtom. Kept as a safety-net in case a future JS-path
    // (in-app banner decline, retry flow, etc.) starts emitting here.
    setIncoming({ type: 'REMOVE_BY_NOTIF_ID', notifEventId });
    // Fire-and-minimize: dispatch the decline then minimize the app once the
    // request settles (success OR failure). Minimizing before sendRtcDecline
    // resolves risks the WebView getting paused mid-request on slower devices;
    // waiting for settlement gives the network call the tick it needs.
    const minimize = () => {
      if (!isNativePlatform()) return;
      App.minimizeApp().catch(() => {
        /* minimize not supported / already in background */
      });
    };
    mx.sendRtcDecline(roomId, notifEventId).then(
      () => minimize(),
      (err: unknown) => {
        // eslint-disable-next-line no-console
        console.warn('[call] sendRtcDecline (from push action) failed', err);
        minimize();
      }
    );
  }, [pending, setPending, setIncoming, setOverLock, switchOrStartDmCall, store, mx]);
};