import { useEffect } from 'react';
import { useNavigate, useParams } from 'react-router-dom';
import { useQueryClient } from '@tanstack/react-query';
import { Lock } from 'lucide-react';
import { isParticleDeleted, type Particle } from '@/api/types';
import { useLiveParticle } from '@/hooks/use-particle';
import { particlePath, type ParticlePath } from '@/lib/particle-path';
import { Button } from '@/components/ui/button';

import Layout from '@/features/layout';
import { StreamView } from '@/features/particles/stream-view';
import { FolderView } from '@/features/particles/folder-view';
import { MediaParticleView } from '@/features/particles/media-particle-view';
import { TextParticleView } from '@/features/particles/text-particle-view';
import { TaskParticleView } from '@/features/particles/task-particle-view';
import { FallbackParticleView } from '@/features/particles/fallback-particle-view';
import { DeletedParticleView } from '@/features/particles/deleted-particle-view';

/**
 * Route-level component for /:networkId/*.
 * Reads params from the router, resolves the particle, and renders
 * the appropriate view based on particle type.
 */
export default function ParticleViewResolver() {
  const { networkId, '*': rest } = useParams();
  if (!networkId)
    throw new Error('ParticleViewResolver requires a :networkId route param');
  const segments = (rest ?? '').split('/').filter(Boolean);
  const path = particlePath(networkId, segments); // path of current container particle

  const { particle, isLoading, error } = useLiveParticle(path);

  if (isLoading) {
    return (
      <Layout>
        <div className="flex h-full items-center justify-center">
          <p className="text-muted-foreground text-sm">Loading...</p>
        </div>
      </Layout>
    );
  }

  if (error || !particle) {
    // Errors here are almost always Firestore permission-denied — the user lost
    // access to the network or to a custom-visibility particle. The React Router
    // stays on the dead route, so without an explicit escape the user is stuck.
    return (
      <Layout>
        <InaccessibleParticle />
      </Layout>
    );
  }

  // Streams render their own full-screen chrome; folders and leaves live
  // inside the app Layout (breadcrumbs, full-height column) like the root.
  switch (particle.type) {
    case 'stream':
      return <StreamView streamParticle={particle} path={path} />;
    case 'folder':
      return (
        <Layout>
          <FolderView folderParticle={particle} path={path} />
        </Layout>
      );
    default:
      return (
        <Layout>
          <LeafParticleView
            particle={particle}
            containerPath={particlePath(networkId, segments.slice(0, -1))}
            networkId={networkId}
          />
        </Layout>
      );
  }
}

const noop = () => {};

/**
 * Standalone view for a leaf particle opened directly (e.g. from a folder),
 * outside any stream playback: renders the particle's native view with no
 * auto-advance.
 */
function LeafParticleView({
  particle,
  containerPath,
  networkId,
}: {
  particle: Particle;
  containerPath: ParticlePath;
  networkId: string;
}) {
  const content = (() => {
    if (isParticleDeleted(particle)) {
      return (
        <DeletedParticleView
          particle={particle}
          networkId={networkId}
          paused
          onEnded={noop}
        />
      );
    }
    switch (particle.type) {
      case 'media':
        return (
          <MediaParticleView
            particle={particle}
            streamPath={containerPath}
            paused={false}
            onEnded={noop}
          />
        );
      case 'text':
        return (
          <TextParticleView
            particle={particle}
            streamPath={containerPath}
            paused
            onEnded={noop}
          />
        );
      case 'task':
        return (
          <TaskParticleView
            particle={particle}
            containerPath={containerPath}
            paused
            onEnded={noop}
          />
        );
      default:
        return (
          <FallbackParticleView particle={particle} networkId={networkId} />
        );
    }
  })();

  return (
    <div className="min-h-0 flex-1 bg-black text-white [--stream-safe-top:2rem] [--stream-safe-bottom:2rem]">
      {content}
    </div>
  );
}

function InaccessibleParticle() {
  const navigate = useNavigate();
  const queryClient = useQueryClient();

  useEffect(() => {
    // Refresh the networks list so the home page reflects current access.
    queryClient.invalidateQueries({ queryKey: ['networks'] });
  }, [queryClient]);

  return (
    <div className="flex h-full flex-col items-center justify-center gap-4 p-8 text-center">
      <Lock className="text-muted-foreground size-8" />
      <div className="flex max-w-sm flex-col gap-1">
        <p className="text-sm font-medium">This particle isn't available</p>
        <p className="text-muted-foreground text-xs">
          It may have been deleted, or your access was removed.
        </p>
      </div>
      <Button size="sm" onClick={() => navigate('/', { replace: true })}>
        Go home
      </Button>
    </div>
  );
}
