import { useState } from "react";
import { useTranslation } from "react-i18next";
import { useQuery } from "@tanstack/react-query";
import {
  Bookmark,
  BookmarkX,
  Check,
  Download,
  Eye,
  EyeOff,
  Filter,
  FilterX,
  Info,
  ListPlus,
  Play,
  RotateCcw,
  SkipBack,
  Tv,
  Undo2,
} from "lucide-react";

import { api, type Video, type VideoStatus } from "../lib/api";
import { isResettable } from "../lib/api/feed";
import { qk } from "../lib/queryKeys";
import { pinVideo, useComfortPin } from "./comfortPin";
import { useCopyItems } from "./copyItems";
import { useNavigationActions } from "./navigationContext";
import { type ActionMenuItem } from "./ui/ActionMenu";
import { VideoFollowUp, type VideoFollowUpState } from "./VideoFollowUp";

// A video's ONE action list (docs/DESIGN.md "Action placement"). The right-click, the
// long-press, Shift+F10 and the card's "…" all open a menu built here, so the feed, a channel page
// and the Home shelves list the same actions in the same order. The card itself keeps only its
// state and the everyday toggles (watched, save, add to playlist) on hover; everything else —
// download, details, copy, hide, reset, pin — lives here, and only here.

export interface VideoActionHandlers {
  onState: (id: string, status: VideoStatus) => void;
  onToggleSave: (id: string, saved: boolean) => void;
  /** Omitted where a surface cannot reset a video's state (Home's shelves). */
  onResetState?: (id: string) => void;
  /** Omitted where the host menu leads with its own Play row (Home's shelf card resolves `next`). */
  onOpen?: (v: Video, startAt?: number | null) => void;
  /** The feed's channel filter, where the menu can narrow it: the library feed. Omitted on a channel
   *  page (the view is that channel already), in a live YouTube search and on Home. */
  channelFilter?: { ids: string[]; set: (ids: string[]) => void };
}

const icon = "w-4 h-4";

/** `open` is the host menu's own flag: the download state and the shelf are fetched only once a
 *  menu has been opened, since they only label a row. Returns the item builder and the follow-up
 *  panel to render beside the menu (one per list). */
export function useVideoActions(handlers: VideoActionHandlers, open: boolean) {
  const { t } = useTranslation();
  const { openChannel } = useNavigationActions();
  const pin = useComfortPin(open);
  const copy = useCopyItems();
  const index = useQuery({
    queryKey: qk.downloadIndex(),
    queryFn: api.downloadIndex,
    enabled: open,
    staleTime: 10000,
  });
  const [followUp, setFollowUp] = useState<VideoFollowUpState | null>(null);

  /** `pin: false` where the host menu carries its own shelf rows (Home's rails). */
  const items = (
    v: Video,
    anchor: Element | null,
    { pin: withPin = true }: { pin?: boolean } = {},
  ): ActionMenuItem[] => {
    const { onState, onToggleSave, onResetState, onOpen, channelFilter } = handlers;
    const watched = v.status === "watched";
    const hidden = v.status === "hidden";
    const inProgress = v.position_seconds > 0 && !watched;
    const dl = index.data?.[v.id];
    // The row opens the download dialog, so it says so; the download's state is the line under its
    // label — "Downloaded" read as a status, not as a row that opens something — and
    // not a `title`, which a key or a finger never shows.
    const dlState =
      dl === "done"
        ? t("downloads.button.downloaded")
        : dl === "queued" || dl === "running" || dl === "paused"
          ? t("downloads.button.queued")
          : undefined;
    // The two panels open beside the object; a menu opened with no element to anchor to (none of
    // the triggers does that today) leaves them out rather than opening them at the corner.
    const at = (kind: "playlist" | "details") =>
      anchor ? () => setFollowUp({ kind, video: v, anchor }) : null;
    const addTo = at("playlist");
    const details = at("details");
    return [
      ...(onOpen
        ? [
            {
              id: "play",
              label: inProgress ? t("card.continue") : t("card.play"),
              icon: <Play className={icon} />,
              onSelect: () => onOpen(v, null),
            },
            ...(inProgress
              ? [
                  {
                    id: "restart",
                    label: t("card.restartTitle"),
                    icon: <SkipBack className={icon} />,
                    onSelect: () => onOpen(v, 0),
                  },
                ]
              : []),
          ]
        : []),
      {
        id: "channel",
        label: t("card.menu.openChannel"),
        icon: <Tv className={icon} />,
        onSelect: () => openChannel(v.channel_id, v.channel_title ?? t("card.thisChannel")),
      },
      // The channel's videos in this feed, or the channel out of the filter again: channels OR
      // together, so adding one widens a filter that already names others (as "Show in feed" does).
      ...(channelFilter
        ? [
            channelFilter.ids.includes(v.channel_id)
              ? {
                  id: "channel-filter",
                  label: t("card.menu.channelFilterRemove"),
                  icon: <FilterX className={icon} />,
                  onSelect: () =>
                    channelFilter.set(channelFilter.ids.filter((id) => id !== v.channel_id)),
                }
              : {
                  id: "channel-filter",
                  label: t("card.menu.channelFilterAdd"),
                  icon: <Filter className={icon} />,
                  onSelect: () => channelFilter.set([...channelFilter.ids, v.channel_id]),
                },
          ]
        : []),
      {
        id: "watched",
        label: watched ? t("card.menu.unmarkWatched") : t("card.markWatched"),
        icon: watched ? <Undo2 className={icon} /> : <Check className={icon} />,
        separatorBefore: true,
        onSelect: () => onState(v.id, watched ? "new" : "watched"),
      },
      {
        id: "save",
        label: v.saved ? t("card.menu.unsave") : t("card.saveForLater"),
        icon: v.saved ? <BookmarkX className={icon} /> : <Bookmark className={icon} />,
        onSelect: () => onToggleSave(v.id, !v.saved),
      },
      ...(addTo
        ? [
            {
              id: "playlist",
              label: t("playlists.addToPlaylist"),
              icon: <ListPlus className={icon} />,
              onSelect: addTo,
            },
          ]
        : []),
      {
        id: "download",
        label: t("downloads.menu.download"),
        note: dlState,
        icon: <Download className={icon} />,
        onSelect: () => setFollowUp({ kind: "download", video: v }),
      },
      ...(details
        ? [
            {
              id: "details",
              label: t("card.info"),
              icon: <Info className={icon} />,
              separatorBefore: true,
              onSelect: details,
            },
          ]
        : []),
      ...copy(v.title, v.watch_url).map((it, i) =>
        i === 0 && !details ? { ...it, separatorBefore: true } : it,
      ),
      {
        id: "hide",
        label: hidden ? t("card.unhide") : t("card.hide"),
        icon: hidden ? <Eye className={icon} /> : <EyeOff className={icon} />,
        separatorBefore: true,
        onSelect: () => onState(v.id, hidden ? "new" : "hidden"),
      },
      ...(onResetState && isResettable(v)
        ? [
            {
              id: "reset",
              label: t("card.resetState"),
              icon: <RotateCcw className={icon} />,
              onSelect: () => onResetState(v.id),
            },
          ]
        : []),
      ...(withPin ? pin.item(pinVideo(v.id), v.title ?? "") : []),
    ];
  };

  const panel = followUp && <VideoFollowUp state={followUp} onClose={() => setFollowUp(null)} />;
  return { items, panel };
}