import { useEffect, useRef, useState, type RefObject } from "react";
import type { MediaParticleHandle } from "@/features/particles/media-particle-view";
import { useSuspendPlayback } from "@/hooks/use-suspend-playback";
import { selectIsPaused, usePlaybackPauseStore } from "@/stores/playback-pause-store";
import { isTypingTarget } from "@/lib/keyboard";
import { set } from "zod";

const SPACE_TAP_THRESHOLD_MS = 250;

interface UsePlaybackKeysOptions {
  mediaRef: RefObject<MediaParticleHandle | null>;
}

interface UsePlaybackKeysResult {
  fastPlayback: boolean;
}

/**
 * Hold-space to pause, hold-shift for 1.5x. Space is always handled (it
 * manages its own suspender via useSuspendPlayback); other keys bail when
 * playback is already paused for an external reason.
 */
export function usePlaybackKeys({ mediaRef }: UsePlaybackKeysOptions): UsePlaybackKeysResult {
  const [spaceHeld, setSpaceHeld] = useState(false);
  const [fastPlayback, setFastPlayback] = useState(false);
  const spaceStartRef = useRef(0);

  useSuspendPlayback(spaceHeld, "hold-space");

  useEffect(() => {
    const isExternallyPaused = () =>
      selectIsPaused(usePlaybackPauseStore.getState()) && !spaceHeld;

    const onKeyDown = (e: KeyboardEvent) => {
      if (isTypingTarget(e)) return;

      if (e.key === " ") {
        e.preventDefault();
        if (!e.repeat) {
          if (spaceHeld) {
            setSpaceHeld(false);
            spaceStartRef.current = 0;
          } else {
            setSpaceHeld(true);
            spaceStartRef.current = Date.now();
          }
        }
        return;
      }

      if (isExternallyPaused()) return;

      if (e.key === "Shift" && !e.repeat) {
        mediaRef.current?.setPlaybackRate(1.5);
        setFastPlayback(true);
      }
    };

    const onKeyUp = (e: KeyboardEvent) => {
      if (isTypingTarget(e)) return;

      if (e.key === " ") {
        e.preventDefault();

        // keep space-held if it was a quick tap, to allow for space-to-toggle behavior
        if (Date.now() - spaceStartRef.current < SPACE_TAP_THRESHOLD_MS) {
          return;
        }

        setSpaceHeld(false);
        spaceStartRef.current = 0;
        return;
      }

      if (isExternallyPaused()) return;

      if (e.key === "Shift") {
        mediaRef.current?.setPlaybackRate(1);
        setFastPlayback(false);
      }
    };

    window.addEventListener("keydown", onKeyDown);
    window.addEventListener("keyup", onKeyUp);
    return () => {
      window.removeEventListener("keydown", onKeyDown);
      window.removeEventListener("keyup", onKeyUp);
    };
  }, [mediaRef, spaceHeld]);

  return { fastPlayback };
}