llink/js/mobile/src/hooks/use-particle.ts

import { useState, useEffect } from "react";
import { useQuery } from "@tanstack/react-query";
import type { QueryFieldFilterConstraint } from "firebase/firestore";
import {
  subscribeToParticle,
  subscribeToParticleChildren,
  subscribeToLatestChild,
  getParticle,
  getParticleChildren,
} from "@/lib/firestore-particles";
import type { Particle } from "@/api/types";
import {
  type ParticlePath,
  toFirestoreDocPath,
  toFirestoreChildrenPath,
} from "@/lib/particle-path";
import { logError } from "@/lib/errors";

interface UseLiveParticleResult {
  particle: Particle | null;
  isLoading: boolean;
  error: Error | null;
}

export function useLiveParticle(path: ParticlePath): UseLiveParticleResult {
  const [particle, setParticle] = useState<Particle | null>(null);
  const [isLoading, setIsLoading] = useState(true);
  const [error, setError] = useState<Error | null>(null);

  useEffect(() => {
    setIsLoading(true);
    setError(null);
    setParticle(null);

    const docPath = toFirestoreDocPath(path);
    const unsubscribe = subscribeToParticle(
      docPath,
      (data) => {
        setParticle(data);
        setIsLoading(false);
      },
      (err) => {
        setError(err);
        setIsLoading(false);
      },
    );

    return unsubscribe;
  }, [path]);

  return { particle, isLoading, error };
}

interface UseLiveParticleChildrenResult {
  children: Particle[];
  isLoading: boolean;
  error: Error | null;
}

interface UseLiveParticleChildrenParams {
  orderByField?: string;
  orderDirection?: "asc" | "desc";
  visibilityScopes?: string[];
  onAdded?: (child: Particle) => void;
  onRemoved?: (child: Particle, updatedChildren: Particle[]) => void;
  whereFilter?: QueryFieldFilterConstraint;
  /** Optional cap on results. Changes trigger a re-subscription. */
  limit?: number;
}

export function useLiveParticleChildren(
  path: ParticlePath | undefined,
  {
    orderByField = "created_at",
    orderDirection = "desc",
    visibilityScopes,
    onAdded,
    onRemoved,
    whereFilter,
    limit,
  }: UseLiveParticleChildrenParams = {},
): UseLiveParticleChildrenResult {
  const [children, setChildren] = useState<Particle[]>([]);
  const [isLoading, setIsLoading] = useState(true);
  const [error, setError] = useState<Error | null>(null);

  useEffect(() => {
    if (!path) {
      setChildren([]);
      setIsLoading(false);
      return;
    }

    setIsLoading(true);
    setError(null);
    setChildren([]);

    const collectionPath = toFirestoreChildrenPath(path);

    const unsubscribe = subscribeToParticleChildren(collectionPath, {
      onData: (data) => {
        setChildren(data);
        setIsLoading(false);
      },
      onError: (err) => {
        logError(err, { scope: "firestore.particle-children", path });
        setError(err);
        setIsLoading(false);
      },
      visibilityScopes,
      orderByField,
      orderDirection,
      onAdded,
      onRemoved,
      whereFilter,
      limit,
    });

    return unsubscribe;
    // The hook intentionally keys only on path/whereFilter/limit — desktop
    // does the same. Visibility scope changes are absorbed by the active
    // listener; reordering causes a re-subscription.
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [path, whereFilter, limit]);

  return { children, isLoading, error };
}

interface UseLiveLatestChildResult {
  latestChild: Particle | null;
  isLoading: boolean;
}

export function useLiveLatestChild(
  path: ParticlePath,
): UseLiveLatestChildResult {
  const [latestChild, setLatestChild] = useState<Particle | null>(null);
  const [isLoading, setIsLoading] = useState(true);

  useEffect(() => {
    setIsLoading(true);
    setLatestChild(null);

    const unsubscribe = subscribeToLatestChild(
      toFirestoreChildrenPath(path),
      (data) => {
        setLatestChild(data);
        setIsLoading(false);
      },
      (err) => {
        logError(err, { scope: "firestore.latest-child", path });
        setIsLoading(false);
      },
    );

    return unsubscribe;
  }, [path]);

  return { latestChild, isLoading };
}

export function useParticle(path?: ParticlePath) {
  return useQuery({
    queryKey: ["particle", path],
    queryFn: async () => {
      if (!path) return null;
      const docPath = toFirestoreDocPath(path);
      const particle = await getParticle(docPath);
      return particle;
    },
    enabled: !!path,
  });
}

export function useParticleChildren(path?: ParticlePath) {
  return useQuery({
    queryKey: ["particle-children", path],
    queryFn: async () => {
      if (!path) return [];
      const collectionPath = toFirestoreChildrenPath(path);
      return getParticleChildren(collectionPath);
    },
    enabled: !!path,
    staleTime: 1000 * 60 * 5, // 5 min — attachments don't change
  });
}