frontend/src/hooks/useInference.ts

import { useCallback } from "react";
import { detectAudio, detectSample, visualizeAudio } from "@/lib/api";
import { useInferenceStore } from "@/store/inferenceStore";

export function useInference() {
  const setIsInferring = useInferenceStore((s) => s.setIsInferring);
  const setResult = useInferenceStore((s) => s.setResult);
  const setViz = useInferenceStore((s) => s.setViz);
  const setError = useInferenceStore((s) => s.setError);
  const audio = useInferenceStore((s) => s.audio);
  const selectedModels = useInferenceStore((s) => s.selectedModels);

  const fileFromAudio = useCallback((): File | null => {
    if (!audio) return null;
    if (audio.kind === "file") return audio.file;
    if (audio.kind === "recording") {
      const ext =
        audio.blob.type.includes("webm")
          ? "webm"
          : audio.blob.type.includes("ogg")
            ? "ogg"
            : "wav";
      return new File([audio.blob], `recording.${ext}`, { type: audio.blob.type });
    }
    return null;
  }, [audio]);

  const run = useCallback(async () => {
    if (!audio) return;
    setIsInferring(true);
    setError(null);
    setResult(null);
    try {
      const models = selectedModels.length ? selectedModels : undefined;

      if (audio.kind === "sample") {
        const res = await detectSample(audio.sampleId, models, true);
        setResult(res);
        setViz(null);
        return;
      }

      const file = fileFromAudio();
      if (!file) throw new Error("No audio source available.");

      // Run inference and visualization in parallel. Re-throw viz errors via
      // store so the Demo page can surface them.
      const [det, viz] = await Promise.all([
        detectAudio(file, models, true),
        visualizeAudio(file).catch((vizExc) => {
          // Don't fail the whole pipeline because viz failed — but log so the
          // page can pick it up. The Demo page also runs visualize directly.
          // eslint-disable-next-line no-console
          console.warn("visualize failed during inference:", vizExc);
          return null;
        }),
      ]);
      setResult(det);
      if (viz) setViz(viz);
    } catch (e: unknown) {
      const msg =
        e && typeof e === "object" && "message" in e
          ? String((e as { message: string }).message)
          : "Inference failed";
      setError(msg);
    } finally {
      setIsInferring(false);
    }
  }, [audio, selectedModels, setError, setIsInferring, setResult, setViz, fileFromAudio]);

  return { run };
}