import { useState } from "react";
import { qk } from "../lib/queryKeys";
import { useTranslation } from "react-i18next";
import { plexLang } from "../i18n";
import { useQuery, useQueryClient } from "@tanstack/react-query";
import { ListMusic, Plus, SlidersHorizontal, X } from "lucide-react";
import { api, plexFilterCount, type PlexFilters } from "../lib/api";
import { type PanelLayout } from "../lib/panelLayout";
import { type MediaSourceKind } from "../lib/mediaSource";
import { useDebounced } from "../lib/useDebounced";
import FilterRail from "./FilterRail";
import { type PanelItem } from "./PanelGroups";
import SegmentedToggle from "./SegmentedToggle";
import FilterChipGroup from "./FilterChipGroup";
import Combobox, { type ComboboxOption } from "./Combobox";
import SavedViewsPopover from "./SavedViewsPopover";
import PersonalViewsModal from "./PersonalViewsModal";
import { useSavedViews } from "./SavedViewsProvider";
import { usePlex, usePlexActions } from "./PlexProvider";
import { useMe } from "../lib/useMe";

// The Plex module's left filter column — now the shared floating SidePanel with its filter groups
// as reorderable "islands" (same system as the feed rail). Movie libraries get the full metadata
// set; shows keep library + sort. State is owned by App (per-account persisted); facets come from
// the backend so the panel only offers what the library actually contains.

type Props = {
  layout: PanelLayout;
  setLayout: (l: PanelLayout) => void;
  collapsed: boolean;
  onToggleCollapse: () => void;
};

const RATING_STEPS = [5, 6, 7, 8, 9];
const ADDED_OPTS = ["24h", "1w", "1m", "6m", "1y"] as const;
const DURATION_BUCKETS: { key: string; min: number | null; max: number | null }[] = [
  { key: "short", min: null, max: 90 * 60 },
  { key: "mid", min: 90 * 60, max: 120 * 60 },
  { key: "long", min: 120 * 60, max: null },
];

// The any/all combine toggle for a multi-value filter (genres, actors) — a thin binding of the shared
// SegmentedToggle to the Plex match vocabulary (same look as the feed rail's tag MATCH toggle).
function MatchToggle({
  mode,
  onChange,
}: {
  mode: "any" | "all";
  onChange: (m: "any" | "all") => void;
}) {
  const { t } = useTranslation();
  return (
    <SegmentedToggle
      label={t("plex.filter.matchLabel")}
      ariaLabel={t("plex.filter.matchLabel")}
      options={[
        { value: "any", label: t("plex.filter.match.any") },
        { value: "all", label: t("plex.filter.match.all") },
      ]}
      value={mode}
      onChange={onChange}
    />
  );
}

export default function PlexSidebar({ layout, setLayout, collapsed, onToggleCollapse }: Props) {
  const { t } = useTranslation();
  // Scope / watch-state / sort / expanded filters live in PlexProvider (shared with PlexBrowse and
  // the header search box); this rail is the primary editor of them. Opening a playlist is a
  // hand-off to PlexBrowse via the shared `playlistOpen` slot.
  const { scope, show, filters } = usePlex();
  const { setFilters } = usePlexActions();
  const isDemo = useMe().is_demo;
  // Personal ("saved") views for the Plex module: the rail header icon opens a quick-pick popover, the
  // title opens the full manager modal (same shared components as the feed). Hidden for the demo account.
  const { openModal, modalOpen } = useSavedViews();
  // This rail's media source (the Plex library) — names the abstraction the feed and Plex rails
  // share; drives the panel layout key. `FilterRail` owns the customize `editing` state now.
  const source: MediaSourceKind = "plex";
  // Titles are display-only (chip labels) — keep them OUT of the facet query key so renaming/relabelling
  // never refetches. collectionMode stays IN the key: any/all changes the result set.
  const { collectionTitles: _cts, ...facetKey } = filters;
  const lang = plexLang(); // HU/EN genre vocabulary — refetch facets on a language switch
  const facetsQ = useQuery({
    queryKey: qk.plexFacets(scope, show, facetKey, lang),
    queryFn: () => api.plexFacets(scope, filters, show, lang),
    enabled: !!scope,
    placeholderData: (prev) => prev,
  });
  const facets = facetsQ.data;

  const fCount = plexFilterCount(filters);
  // Scope and sort moved to the header / above-the-grid toolbar (S3); the panel badge now counts only
  // the filters that still live in this panel (expanded filters + watch-state).
  const activeCount = fCount + (show !== "all" ? 1 : 0);

  const patch = (p: Partial<PlexFilters>) => setFilters({ ...filters, ...p });

  const durBucketKey = DURATION_BUCKETS.find(
    (b) => (filters.durationMin ?? null) === b.min && (filters.durationMax ?? null) === b.max,
  )?.key;
  // Directors + actors have no picker (they're added from the detail/cast surfaces) — this section
  // just lists them as removable chips. Studios now have their own picker section (below).
  const peopleActive = filters.directors.length + filters.actors.length > 0;

  // Group bodies (no title — the PanelGroup card supplies it). Only available groups are pushed,
  // so facet-gated / scope-gated sections drop out cleanly; PanelGroups orders them by the saved
  // layout and lets the user reorder / hide / collapse them.
  const items: PanelItem[] = [
    {
      id: "playlists",
      title: t("plex.playlist.section"),
      body: <PlaylistPicker />,
    },
    ...(peopleActive
      ? [
          {
            id: "people",
            title: t("plex.filter.active"),
            body: (
              <div className="flex flex-wrap gap-1.5">
                {filters.directors.map((d) => (
                  <RemovableChip
                    key={`d:${d}`}
                    label={d}
                    onRemove={() => patch({ directors: filters.directors.filter((x) => x !== d) })}
                  />
                ))}
                {filters.actors.length > 1 && (
                  <div className="w-full">
                    <MatchToggle
                      mode={filters.actorMode ?? "any"}
                      onChange={(m) => patch({ actorMode: m })}
                    />
                  </div>
                )}
                {filters.actors.map((a) => (
                  <RemovableChip
                    key={`a:${a}`}
                    label={a}
                    onRemove={() => patch({ actors: filters.actors.filter((x) => x !== a) })}
                  />
                ))}
              </div>
            ),
          },
        ]
      : []),
    {
      id: "collection",
      title: t("plex.filter.collection"),
      body: (
        <CollectionPicker
          values={filters.collections}
          titles={filters.collectionTitles}
          mode={filters.collectionMode ?? "any"}
          onChange={(collections, collectionTitles) => patch({ collections, collectionTitles })}
          onModeChange={(m) => patch({ collectionMode: m })}
        />
      ),
    },
    {
      id: "rating",
      title: t("plex.filter.rating"),
      body: (
        <FilterChipGroup
          ariaLabel={t("plex.filter.rating")}
          value={filters.ratingMin == null ? "" : String(filters.ratingMin)}
          options={[
            { value: "", label: t("plex.filter.any") },
            ...RATING_STEPS.map((r) => ({ value: String(r), label: `${r}+` })),
          ]}
          onChange={(v) => patch({ ratingMin: v === "" ? null : Number(v) })}
        />
      ),
    },
    ...(facets && facets.genres.length > 0
      ? [
          {
            id: "genre",
            title: t("plex.filter.genre"),
            body: (
              <>
                {filters.genres.length > 1 && (
                  <div className="mb-1.5">
                    <MatchToggle
                      mode={filters.genreMode ?? "any"}
                      onChange={(m) => patch({ genreMode: m })}
                    />
                  </div>
                )}
                <Combobox
                  label={t("plex.filter.genre")}
                  options={facets.genres}
                  selected={filters.genres}
                  onChange={(next) => patch({ genres: next })}
                />
              </>
            ),
          },
        ]
      : []),
    {
      id: "year",
      title: t("plex.filter.year"),
      body: (
        <div className="flex items-center gap-2">
          <NumberInput
            value={filters.yearMin ?? null}
            placeholder={facets?.year_min ?? undefined}
            onChange={(v) => patch({ yearMin: v })}
          />
          <span className="text-muted text-xs">–</span>
          <NumberInput
            value={filters.yearMax ?? null}
            placeholder={facets?.year_max ?? undefined}
            onChange={(v) => patch({ yearMax: v })}
          />
        </div>
      ),
    },
    ...(scope === "movie"
      ? [
          {
            id: "duration",
            title: t("plex.filter.duration"),
            body: (
              <FilterChipGroup
                ariaLabel={t("plex.filter.duration")}
                // "Any" is selected only when there is genuinely no duration filter; a set-but-off-bucket
                // duration (e.g. stale state after a bucket-boundary change) selects nothing, not "Any".
                value={
                  durBucketKey ??
                  (filters.durationMin == null && filters.durationMax == null ? "" : " ")
                }
                options={[
                  { value: "", label: t("plex.filter.any") },
                  ...DURATION_BUCKETS.map((b) => ({
                    value: b.key,
                    label: t(`plex.filter.durationOpt.${b.key}`),
                  })),
                ]}
                onChange={(key) => {
                  const b = DURATION_BUCKETS.find((x) => x.key === key);
                  patch({ durationMin: b?.min ?? null, durationMax: b?.max ?? null });
                }}
              />
            ),
          },
        ]
      : []),
    {
      id: "added",
      title: t("plex.filter.added"),
      body: (
        <FilterChipGroup
          ariaLabel={t("plex.filter.added")}
          value={filters.addedWithin || ""}
          options={[
            { value: "", label: t("plex.filter.any") },
            ...ADDED_OPTS.map((a) => ({ value: a, label: t(`plex.filter.addedOpt.${a}`) })),
          ]}
          onChange={(v) => patch({ addedWithin: v })}
        />
      ),
    },
    ...(facets && facets.content_ratings.length > 0
      ? [
          {
            id: "contentrating",
            title: t("plex.filter.contentRating"),
            body: (
              <Combobox
                label={t("plex.filter.contentRating")}
                options={facets.content_ratings}
                selected={filters.contentRatings}
                onChange={(next) => patch({ contentRatings: next })}
              />
            ),
          },
        ]
      : []),
    ...(facets && facets.studios.length > 0
      ? [
          {
            id: "studio",
            title: t("plex.filter.studio"),
            body: (
              <Combobox
                label={t("plex.filter.studio")}
                options={facets.studios}
                selected={filters.studios}
                onChange={(next) => patch({ studios: next })}
              />
            ),
          },
        ]
      : []),
    // Playback class (Direct Play / Direct Stream / Transcode HW/SW) — movie-only (shows have no
    // class), and dropped when the facet is empty. Labels are localized (the facet ships class keys).
    ...(scope === "movie" && facets && facets.playable.length > 0
      ? [
          {
            id: "playable",
            title: t("plex.filter.playable"),
            body: (
              <Combobox
                label={t("plex.filter.playable")}
                options={facets.playable.map((p) => ({
                  value: p.value,
                  label: t(`plex.filter.playableOpt.${p.value}`),
                  count: p.count,
                }))}
                selected={filters.playable}
                onChange={(next) => patch({ playable: next })}
              />
            ),
          },
        ]
      : []),
  ];

  return (
    <>
      <FilterRail
        kind={source}
        title={t("sidebar.filters")}
        icon={<SlidersHorizontal className="w-4 h-4" />}
        count={activeCount}
        collapsed={collapsed}
        onToggleCollapse={onToggleCollapse}
        layout={layout}
        setLayout={setLayout}
        items={items}
        // The Plex widgets are simple label + control rows now, not collapsible islands (matches the
        // feed rail). The rail's own "Clear all" is dropped too — the chip row above the grid owns it.
        collapsible={false}
        // Saved ("personal") views: header icon → quick-pick popover, title → the manager modal. Hidden
        // for the demo account. Same shared components as the feed rail (SavedViewsProvider switches source).
        iconExpanded={
          isDemo ? undefined : (
            <SavedViewsPopover trigger={<SlidersHorizontal className="w-4 h-4" />} />
          )
        }
        onTitleClick={isDemo ? undefined : openModal}
        titleActionLabel={isDemo ? undefined : t("views.manageTitle")}
      />
      {/* The manager modal lives here (rail is always mounted on plex); Modal portals to <body>. */}
      {modalOpen && <PersonalViewsModal />}
    </>
  );
}

// The playlists section: a combobox that stays compact (just a field + chevron) until opened, instead
// of an always-expanded list that grew the rail with every playlist. Picking a playlist opens it (the
// PlexBrowse `playlistOpen` hand-off); typing a name that doesn't exist yet offers a "Create …" row so
// you can still add one — the same reuse-the-Combobox idea as the feed's "Your tags" widget. `selected`
// stays empty: this picks an action (open / create), it doesn't hold a persistent selection.
const CREATE_PLAYLIST = "__create__";
function PlaylistPicker() {
  const { t } = useTranslation();
  const { setPlaylistOpen: onOpenPlaylist } = usePlexActions();
  const qc = useQueryClient();
  const [query, setQuery] = useState("");
  const playlistsQ = useQuery({ queryKey: qk.plexPlaylists(), queryFn: () => api.plexPlaylists() });
  const playlists = playlistsQ.data?.playlists ?? [];

  const q = query.trim();
  const ql = q.toLowerCase();
  const matches = ql ? playlists.filter((p) => p.title.toLowerCase().includes(ql)) : playlists;
  const exact = playlists.some((p) => p.title.toLowerCase() === ql);
  const options: ComboboxOption[] = [
    ...matches.map((p) => ({ value: `pl:${p.id}`, label: p.title, count: p.item_count })),
    // Offer to create only when the typed name isn't already a playlist.
    ...(q && !exact ? [{ value: CREATE_PLAYLIST, label: q }] : []),
  ];

  async function createPlaylist(title: string) {
    const pl = await api.plexCreatePlaylist(title);
    qc.invalidateQueries({ queryKey: qk.plexPlaylists() });
    onOpenPlaylist(pl.id);
  }

  return (
    <Combobox
      label={t("plex.playlist.section")}
      multiple={false}
      clientFilter={false} // we build `options` (incl. the create row) against the query ourselves
      options={options}
      selected={[]}
      query={query}
      onQueryChange={setQuery}
      placeholder={t("plex.playlist.pickerPlaceholder")}
      emptyText={t("plex.playlist.none")}
      renderOption={(o) =>
        o.value === CREATE_PLAYLIST ? (
          <>
            <Plus className="h-3.5 w-3.5 shrink-0 text-accent" />
            <span className="flex-1 truncate">
              {t("plex.playlist.createNamed", { name: o.label })}
            </span>
          </>
        ) : (
          <>
            <ListMusic className="h-3.5 w-3.5 shrink-0 text-muted" />
            <span className="flex-1 truncate">{o.label}</span>
            {o.count != null && (
              <span className="shrink-0 text-2xs tabular-nums text-muted">{o.count}</span>
            )}
          </>
        )
      }
      onChange={(next) => {
        const v = next[0];
        if (!v) return;
        if (v === CREATE_PLAYLIST) createPlaylist(q);
        else onOpenPlaylist(Number(v.slice(3)));
      }}
    />
  );
}

// The collection filter (E5 S7 → combobox; now multi-select): a combi-input matching the genre/studio
// pickers, its vocabulary searched SERVER-side (the union can run to hundreds). The generic <Combobox>
// owns the field/keyboard/ARIA + the any/all match footer; this wrapper owns the query→fetch (gated on
// `open`) and maps collections to options. A title can belong to several collections, so multiple can
// be picked and combined with Any/All. Titles are carried alongside the ids for the active-filter chips.
function CollectionPicker({
  values,
  titles,
  mode,
  onChange,
  onModeChange,
}: {
  values: string[];
  titles: Record<string, string> | undefined;
  mode: "any" | "all";
  onChange: (values: string[], titles: Record<string, string> | undefined) => void;
  onModeChange: (mode: "any" | "all") => void;
}) {
  const { t } = useTranslation();
  const [open, setOpen] = useState(false);
  const [search, setSearch] = useState("");
  const searchDeb = useDebounced(search.trim(), 300);
  const q = useQuery({
    queryKey: qk.plexCollections("union", searchDeb),
    queryFn: () => api.plexCollections(undefined, searchDeb || undefined),
    enabled: open, // only fetch while the picker is open
  });
  const options: ComboboxOption[] = (q.data?.collections ?? []).map((c) => ({
    value: c.id,
    label: c.title,
    count: c.child_count ?? undefined,
  }));
  // Combine the fetched labels with the ones already stored so the trip through onChange keeps every
  // selected collection's title (the fetched list is narrowed by the current search).
  const labelMap: Record<string, string> = { ...titles };
  for (const o of options) if (o.label) labelMap[o.value] = o.label;

  return (
    <Combobox
      label={t("plex.filter.collection")}
      clientFilter={false} // the server already narrows to `search`
      options={options}
      selected={values}
      selectedLabels={titles}
      query={search}
      onQueryChange={setSearch}
      onOpenChange={setOpen}
      loading={q.isFetching}
      placeholder={t("plex.filter.collectionSearch")}
      emptyText={t("plex.filter.collectionEmpty")}
      matchMode={mode === "all" ? "and" : "or"}
      onMatchModeChange={(m) => onModeChange(m === "and" ? "all" : "any")}
      onChange={(next) => {
        // Carry only the selected ids' titles forward (drop titles for de-selected ones). Collapse an
        // empty map to undefined so a clear-all key-matches the pristine state (an empty {} still hashes
        // differently from an absent key), mirroring the chip-row remove handler.
        const nextTitles: Record<string, string> = {};
        for (const id of next) nextTitles[id] = labelMap[id] ?? titles?.[id] ?? id;
        onChange(next, next.length ? nextTitles : undefined);
      }}
    />
  );
}

function RemovableChip({ label, onRemove }: { label: string; onRemove: () => void }) {
  return (
    <span className="chip px-2 py-1 text-xs">
      <span className="truncate max-w-36">{label}</span>
      <button onClick={onRemove} className="hover:opacity-70" aria-label="remove">
        <X className="w-3 h-3" />
      </button>
    </span>
  );
}

function NumberInput({
  value,
  placeholder,
  onChange,
}: {
  value: number | null;
  placeholder?: number;
  onChange: (v: number | null) => void;
}) {
  return (
    <input
      type="number"
      inputMode="numeric"
      value={value ?? ""}
      placeholder={placeholder != null ? String(placeholder) : ""}
      onChange={(e) => {
        const n = e.target.value === "" ? null : Number(e.target.value);
        onChange(n != null && Number.isFinite(n) ? n : null);
      }}
      className="w-20 rounded-lg border border-border bg-surface px-2 py-1 text-sm tabular-nums focus:outline-hidden focus:ring-2 focus:ring-accent/40"
    />
  );
}