import { lazy, Suspense, useEffect, useMemo, useState } from "react";
import { qk } from "../lib/queryKeys";
import { useTranslation } from "react-i18next";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import {
  Ban,
  CalendarClock,
  ClipboardPaste,
  Copy,
  Download,
  Link2,
  Pause,
  Play,
  Plus,
  RotateCcw,
  Scissors,
  Settings2,
  Share2,
  Pencil,
  Trash2,
} from "lucide-react";
import clsx from "clsx";
import Tabs from "./Tabs";
import { PageToolbar } from "./PageShell";
import { LoadingState, StateMessage } from "./QueryState";
import Modal from "./Modal";
// Lazy: these dialogs/editors open on demand, so they stay out of the Downloads page chunk until
// used (the video editor in particular is heavy — filmstrip + scrubber).
const DownloadDialog = lazy(() => import("./DownloadDialog"));
const ProfileEditor = lazy(() => import("./ProfileEditor"));
const VideoEditor = lazy(() => import("./VideoEditor"));
const ShareDialog = lazy(() => import("./ShareDialog"));
import { useConfirm } from "./ConfirmProvider";
import { useLiveQuery } from "../lib/useLiveQuery";
import { useMe } from "../lib/useMe";
import { api, type DownloadJob } from "../lib/api";
import { invalidateDownloads } from "../lib/downloads";
import { notify } from "../lib/notifications";
import { copyText } from "../lib/clipboard";
import { formatBytes, formatDuration, formatEta, formatSpeed, relativeTime } from "../lib/format";
import { inputCls } from "./ui/form";

const GiB = 1024 ** 3;

const STATUS_CLS: Record<string, string> = {
  queued: "text-muted",
  running: "text-accent",
  paused: "text-amber-400",
  done: "text-emerald-400",
  error: "text-red-400",
  canceled: "text-muted",
};

// Byte-progress phases (show a % bar) vs ffmpeg post-steps (no %, indeterminate pulse).
// "editing" (the phase-2 editor) reports a real % from ffmpeg's out_time, so it gets a bar.
const DOWNLOAD_PHASES = ["video", "audio", "editing"];
const PHASE_KEYS = [
  "video",
  "audio",
  "editing",
  "merging",
  "audio_extract",
  "thumbnail",
  "sponsorblock",
  "metadata",
  "processing",
];

function StatusPill({ job }: { job: DownloadJob }) {
  const { t } = useTranslation();
  // While downloading, show the concrete phase (video / audio / merging) so the user isn't
  // confused by the bar resetting between the separate video and audio streams.
  if (job.status === "running" && job.phase && PHASE_KEYS.includes(job.phase)) {
    return (
      <span className="text-xs font-medium text-accent">{t(`downloads.phase.${job.phase}`)}</span>
    );
  }
  const key = job.expired ? "expired" : job.status;
  return (
    <span className={clsx("text-xs font-medium", STATUS_CLS[job.status] ?? "text-muted")}>
      {t(`downloads.status.${key}`)}
    </span>
  );
}

function Thumb({ job }: { job: DownloadJob }) {
  // Prefer the source thumbnail; fall back to our generated poster for thumbnail-less sources.
  const primary = job.asset?.thumbnail_url || job.poster_url;
  // A remote i.ytimg.com thumbnail 404s once the source video is deleted/privated, leaving a
  // broken image. On load failure fall back to our always-present self-hosted poster.
  const [src, setSrc] = useState(primary);
  useEffect(() => setSrc(primary), [primary]);
  return (
    <div className="w-28 aspect-video shrink-0 rounded-lg overflow-hidden bg-surface border border-border">
      {src ? (
        <img
          src={src}
          alt=""
          loading="lazy"
          className="w-full h-full object-cover"
          onError={() => {
            if (job.poster_url && src !== job.poster_url) setSrc(job.poster_url);
          }}
        />
      ) : null}
    </div>
  );
}

function jobTitle(job: DownloadJob): string {
  return job.display_name || job.asset?.title || job.source_ref;
}

// The channel to show under the title: a user override wins over the auto-extracted asset value.
// `url` is null for sources without a channel link (e.g. reddit) — then it renders as plain text.
function jobChannel(job: DownloadJob): { name: string; url: string | null } {
  return {
    name: job.display_uploader || job.asset?.uploader || job.source_ref,
    url: job.display_uploader_url || job.asset?.uploader_url || null,
  };
}

function IconBtn({
  onClick,
  title,
  danger,
  children,
}: {
  onClick: () => void;
  title: string;
  danger?: boolean;
  children: React.ReactNode;
}) {
  return (
    <button
      onClick={onClick}
      title={title}
      className={clsx(
        "p-1.5 rounded-md hover:bg-surface text-muted transition",
        danger ? "hover:text-red-400" : "hover:text-fg",
      )}
    >
      {children}
    </button>
  );
}

// Compact display of a URL: drop the protocol + trailing slash so "youtube.com/watch?v=…" fits.
function displayUrl(url: string): string {
  try {
    const u = new URL(url);
    return (u.host + u.pathname + u.search).replace(/\/$/, "");
  } catch {
    return url;
  }
}

// "Downloaded from" reference: opens the original page in a new tab, or copies the link.
function SourceRef({ url }: { url: string }) {
  const { t } = useTranslation();
  const copy = async () => {
    if (await copyText(url)) {
      notify({ level: "success", message: t("downloads.source.copied") });
    } else {
      notify({ level: "error", message: t("downloads.source.copyFailed") });
    }
  };
  return (
    <div className="flex items-center gap-1 mt-1 text-xs text-muted min-w-0">
      <Link2 className="w-3 h-3 shrink-0" />
      <a
        href={url}
        target="_blank"
        rel="noopener noreferrer"
        title={`${t("downloads.source.open")} — ${url}`}
        className="truncate hover:text-accent hover:underline"
      >
        {displayUrl(url)}
      </a>
      <button
        onClick={copy}
        aria-label={t("downloads.source.copy")}
        title={t("downloads.source.copy")}
        className="shrink-0 p-0.5 rounded-sm hover:bg-surface hover:text-fg transition"
      >
        <Copy className="w-3 h-3" />
      </button>
    </div>
  );
}

// Channel under the title — a clickable link when a channel URL is known, plain text otherwise.
function ChannelLine({ job }: { job: DownloadJob }) {
  const { name, url } = jobChannel(job);
  if (url) {
    return (
      <div className="text-xs mt-0.5 truncate">
        <a
          href={url}
          target="_blank"
          rel="noopener noreferrer"
          title={url}
          className="text-muted hover:text-accent hover:underline"
        >
          {name}
        </a>
      </div>
    );
  }
  return <div className="text-xs text-muted truncate mt-0.5">{name}</div>;
}

function DownloadRow({
  job,
  onShowError,
  children,
}: {
  job: DownloadJob;
  onShowError?: (job: DownloadJob) => void;
  children?: React.ReactNode;
}) {
  const { t } = useTranslation();
  const running = job.status === "running";
  return (
    <div className="flex gap-3 p-2.5 rounded-xl glass-card glass-hover transition">
      <Thumb job={job} />
      <div className="min-w-0 flex-1">
        <div className="font-medium leading-snug line-clamp-1 flex items-center gap-1.5">
          {job.job_kind === "edit" && (
            <span className="inline-flex items-center gap-1 shrink-0 px-1.5 py-0.5 rounded-sm text-[10px] font-semibold uppercase tracking-wide bg-accent/15 text-accent">
              <Scissors className="w-3 h-3" /> {t("downloads.clipBadge")}
            </span>
          )}
          <span className="truncate">{jobTitle(job)}</span>
        </div>
        <ChannelLine job={job} />
        <div className="flex items-center gap-2 mt-1 text-xs">
          <StatusPill job={job} />
          {job.asset?.size_bytes ? (
            <span className="text-muted">· {formatBytes(job.asset.size_bytes)}</span>
          ) : null}
          {job.asset?.duration_s ? (
            <span className="text-muted">· {formatDuration(job.asset.duration_s)}</span>
          ) : null}
          {job.status === "done" && job.created_at ? (
            <span
              className="text-muted inline-flex items-center gap-1"
              title={new Date(job.created_at).toLocaleString()}
            >
              · <CalendarClock className="w-3 h-3" /> {relativeTime(job.created_at)}
            </span>
          ) : null}
          {job.status === "error" ? (
            <button
              onClick={() => onShowError?.(job)}
              className="text-red-400 hover:text-red-300 inline-flex items-center gap-1 truncate"
              title={t("downloads.errors.fail.title")}
            >
              · {t(`downloads.errors.fail.cat.${job.error_code || "unknown"}.short`)}
              <span className="text-muted underline">{t("downloads.errors.fail.detailsLink")}</span>
            </button>
          ) : null}
        </div>
        {job.source_url && <SourceRef url={job.source_url} />}
        {job.extra_links?.map((url) => (
          <SourceRef key={url} url={url} />
        ))}
        {running && (
          <div className="mt-1.5">
            {job.phase && !DOWNLOAD_PHASES.includes(job.phase) ? (
              // ffmpeg post-steps aren't byte-progress — show an indeterminate pulse, no %.
              <div className="h-1.5 rounded-full bg-surface overflow-hidden">
                <div className="h-full w-full bg-accent/60 animate-pulse" />
              </div>
            ) : (
              <>
                <div className="h-1.5 rounded-full bg-surface overflow-hidden">
                  <div
                    className="h-full bg-accent transition-all"
                    style={{ width: `${job.progress}%` }}
                  />
                </div>
                <div className="text-[11px] text-muted mt-0.5 flex gap-2">
                  <span>{job.progress}%</span>
                  {job.speed_bps ? <span>{formatSpeed(job.speed_bps)}</span> : null}
                  {job.eta_s ? <span>{formatEta(job.eta_s)}</span> : null}
                </div>
              </>
            )}
          </div>
        )}
      </div>
      <div className="flex items-start gap-0.5 shrink-0">{children}</div>
    </div>
  );
}

// --- Rename + Share small modals ------------------------------------------------------------

// Edit a download's display metadata: title, channel (name + link), and extra reference links.
// All are display-only overrides — the on-disk file is never renamed.
function MetaEditModal({ job, onClose }: { job: DownloadJob; onClose: () => void }) {
  const { t } = useTranslation();
  const qc = useQueryClient();
  const [name, setName] = useState(job.display_name || job.asset?.title || "");
  const [channel, setChannel] = useState(job.display_uploader || job.asset?.uploader || "");
  const [channelUrl, setChannelUrl] = useState(
    job.display_uploader_url || job.asset?.uploader_url || "",
  );
  // Editable extra-link rows; keep one blank row so there's always somewhere to type.
  const [links, setLinks] = useState<string[]>(() => [...(job.extra_links ?? []), ""]);

  const setLink = (i: number, v: string) => setLinks((ls) => ls.map((l, j) => (j === i ? v : l)));
  const addLink = () => setLinks((ls) => [...ls, ""]);
  const removeLink = (i: number) => setLinks((ls) => ls.filter((_, j) => j !== i));

  const save = useMutation({
    mutationFn: () =>
      api.updateDownloadMeta(job.id, {
        display_name: name.trim(),
        display_uploader: channel.trim(),
        display_uploader_url: channelUrl.trim(),
        extra_links: links.map((l) => l.trim()).filter(Boolean),
      }),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: qk.downloads() });
      onClose();
    },
  });

  return (
    <Modal title={t("downloads.edit.title")} onClose={onClose}>
      <div className="space-y-3">
        <label className="block">
          <span className="block text-sm font-medium mb-1">{t("downloads.edit.name")}</span>
          <input
            value={name}
            onChange={(e) => setName(e.target.value)}
            className={inputCls}
            autoFocus
          />
        </label>
        <label className="block">
          <span className="block text-sm font-medium mb-1">{t("downloads.edit.channel")}</span>
          <input
            value={channel}
            onChange={(e) => setChannel(e.target.value)}
            className={inputCls}
          />
        </label>
        <label className="block">
          <span className="block text-sm font-medium mb-1">{t("downloads.edit.channelUrl")}</span>
          <input
            value={channelUrl}
            onChange={(e) => setChannelUrl(e.target.value)}
            placeholder="https://…"
            className={inputCls}
          />
        </label>
        <div>
          <span className="block text-sm font-medium mb-1">{t("downloads.edit.extraLinks")}</span>
          <div className="space-y-2">
            {links.map((l, i) => (
              <div key={i} className="flex gap-2">
                <input
                  value={l}
                  onChange={(e) => setLink(i, e.target.value)}
                  placeholder="https://…"
                  className={inputCls}
                />
                <IconBtn
                  onClick={() => removeLink(i)}
                  title={t("downloads.edit.removeLink")}
                  danger
                >
                  <Trash2 className="w-4 h-4" />
                </IconBtn>
              </div>
            ))}
          </div>
          <button
            onClick={addLink}
            className="mt-2 inline-flex items-center gap-1.5 text-sm text-muted hover:text-fg transition"
          >
            <Plus className="w-4 h-4" /> {t("downloads.edit.addLink")}
          </button>
        </div>
        <p className="text-xs text-muted">{t("downloads.edit.hint")}</p>
        <div className="flex justify-end">
          <button
            onClick={() => save.mutate()}
            disabled={!name.trim() || save.isPending}
            className="px-3 py-1.5 rounded-lg text-sm font-medium bg-accent text-accent-fg hover:opacity-90 disabled:opacity-50 transition"
          >
            {t("downloads.edit.save")}
          </button>
        </div>
      </div>
    </Modal>
  );
}

// --- Error detail modal ---------------------------------------------------------------------

// Transient failures worth an in-modal Retry button; the rest are permanent (private/geo/DRM/…),
// where a retry can't help — the queue row still keeps its own retry control regardless.
const RETRYABLE_ERRORS = ["postprocess", "network", "unknown"];

// A readable "why did this fail" window for a failed job: a category headline + plain explanation,
// the raw yt-dlp/ffmpeg text behind a disclosure, and a Retry when the failure may be transient.
function ErrorModal({
  job,
  onRetry,
  onClose,
}: {
  job: DownloadJob;
  onRetry: () => void;
  onClose: () => void;
}) {
  const { t } = useTranslation();
  const code = job.error_code || "unknown";
  const [showRaw, setShowRaw] = useState(false);
  const retryable = RETRYABLE_ERRORS.includes(code);
  return (
    <Modal title={t("downloads.errors.fail.title")} onClose={onClose}>
      <div className="space-y-3">
        <div className="font-medium">{t(`downloads.errors.fail.cat.${code}.short`)}</div>
        <p className="text-sm text-muted">{t(`downloads.errors.fail.cat.${code}.body`)}</p>
        {job.error && (
          <div>
            <button
              onClick={() => setShowRaw((v) => !v)}
              className="text-xs text-muted hover:text-fg transition"
            >
              {t("downloads.errors.fail.detailsToggle")}
            </button>
            {showRaw && (
              <pre className="mt-1.5 text-xs bg-surface rounded-lg p-2.5 overflow-x-auto whitespace-pre-wrap wrap-break-word max-h-40 text-muted">
                {job.error}
              </pre>
            )}
          </div>
        )}
        <div className="flex justify-end gap-2 pt-1">
          {retryable && (
            <button
              onClick={() => {
                onRetry();
                onClose();
              }}
              className="px-3 py-1.5 rounded-lg text-sm font-medium bg-accent text-accent-fg hover:opacity-90 transition"
            >
              {t("downloads.actions.retry")}
            </button>
          )}
          <button
            onClick={onClose}
            className="px-3 py-1.5 rounded-lg text-sm text-muted hover:text-fg hover:bg-surface transition"
          >
            {t("common.close")}
          </button>
        </div>
      </div>
    </Modal>
  );
}

// --- Usage bar ------------------------------------------------------------------------------

function UsageBar() {
  const { t } = useTranslation();
  // Poll live (like the library list) so the footprint updates the moment the worker finishes an
  // edit/download — enqueue only creates a queued job (0 bytes), the size lands asynchronously, so
  // a one-shot fetch at enqueue time would show a stale 0 B until a manual reload.
  const usage = useLiveQuery(qk.downloadUsage(), api.downloadUsage, { intervalMs: 2000 });
  const u = usage.data;
  if (!u) return null;
  const pct =
    u.unlimited || !u.max_bytes ? 0 : Math.min(100, (u.footprint_bytes / u.max_bytes) * 100);
  return (
    <div className="rounded-xl glass-card p-3 mb-4">
      <div className="flex justify-between text-sm mb-1.5">
        <span className="font-medium">{t("downloads.usage.title")}</span>
        <span className="text-muted">
          {formatBytes(u.footprint_bytes)}
          {u.unlimited ? "" : ` / ${formatBytes(u.max_bytes)}`} ·{" "}
          {u.unlimited
            ? t("downloads.usage.unlimited")
            : t("downloads.usage.items", { used: u.active_jobs, max: u.max_jobs })}
        </span>
      </div>
      {!u.unlimited && (
        <div className="h-2 rounded-full bg-surface overflow-hidden">
          <div
            className={clsx("h-full transition-all", pct > 90 ? "bg-red-400" : "bg-accent")}
            style={{ width: `${pct}%` }}
          />
        </div>
      )}
    </div>
  );
}

// --- Admin system tab -----------------------------------------------------------------------

function QuotaModal({
  userId,
  email,
  onClose,
}: {
  userId: number;
  email: string;
  onClose: () => void;
}) {
  const { t } = useTranslation();
  const qc = useQueryClient();
  const q = useQuery({
    queryKey: qk.dlQuota(userId),
    queryFn: () => api.adminGetDownloadQuota(userId),
  });
  const [form, setForm] = useState<{
    gb: number;
    jobs: number;
    conc: number;
    unlimited: boolean;
  } | null>(null);
  const cur = q.data;
  const state =
    form ??
    (cur
      ? {
          gb: Math.round((cur.max_bytes / GiB) * 10) / 10,
          jobs: cur.max_jobs,
          conc: cur.max_concurrent,
          unlimited: cur.unlimited,
        }
      : null);
  const done = () => {
    qc.invalidateQueries({ queryKey: qk.dlQuota(userId) });
    qc.invalidateQueries({ queryKey: qk.adminStorage() });
    onClose();
  };
  const save = useMutation({
    mutationFn: () =>
      api.adminSetDownloadQuota(userId, {
        max_bytes: Math.round(state!.gb * GiB),
        max_jobs: state!.jobs,
        max_concurrent: state!.conc,
        unlimited: state!.unlimited,
      }),
    onSuccess: done,
  });
  const reset = useMutation({
    mutationFn: () => api.adminResetDownloadQuota(userId),
    onSuccess: done,
  });
  if (!state) return null;
  const upd = (p: Partial<typeof state>) => setForm({ ...state, ...p });
  return (
    <Modal title={t("downloads.admin.quotaTitle", { email })} onClose={onClose}>
      <div className="space-y-3">
        <div className="grid grid-cols-3 gap-3">
          <label className="text-sm">
            {t("downloads.admin.maxBytes")}
            <input
              type="number"
              value={state.gb}
              onChange={(e) => upd({ gb: Number(e.target.value) })}
              className={inputCls}
              disabled={state.unlimited}
            />
          </label>
          <label className="text-sm">
            {t("downloads.admin.maxJobs")}
            <input
              type="number"
              value={state.jobs}
              onChange={(e) => upd({ jobs: Number(e.target.value) })}
              className={inputCls}
            />
          </label>
          <label className="text-sm">
            {t("downloads.admin.maxConcurrent")}
            <input
              type="number"
              value={state.conc}
              onChange={(e) => upd({ conc: Number(e.target.value) })}
              className={inputCls}
            />
          </label>
        </div>
        <label className="flex items-center gap-2 text-sm cursor-pointer">
          <input
            type="checkbox"
            checked={state.unlimited}
            onChange={(e) => upd({ unlimited: e.target.checked })}
          />
          {t("downloads.admin.unlimited")}
        </label>
        <div className="flex justify-between pt-1">
          <button
            onClick={() => reset.mutate()}
            className="px-3 py-1.5 rounded-lg text-sm text-muted hover:text-fg hover:bg-surface transition"
          >
            {t("downloads.admin.reset")}
          </button>
          <button
            onClick={() => save.mutate()}
            disabled={save.isPending}
            className="px-3 py-1.5 rounded-lg text-sm font-medium bg-accent text-accent-fg hover:opacity-90 disabled:opacity-50 transition"
          >
            {t("downloads.admin.save")}
          </button>
        </div>
      </div>
    </Modal>
  );
}

// Pick ANY user to set a download quota for — even one who hasn't downloaded anything yet (the
// footprint list below only shows users who already have files).
function QuotaUserPicker({ onPick }: { onPick: (u: { id: number; email: string }) => void }) {
  const { t } = useTranslation();
  const [q, setQ] = useState("");
  const [open, setOpen] = useState(false);
  const users = useQuery({ queryKey: qk.adminUsers(), queryFn: api.adminUsers });
  const list = (users.data ?? []).filter((u) => !u.is_demo);
  const filtered = useMemo(() => {
    const s = q.trim().toLowerCase();
    const base = s
      ? list.filter(
          (u) =>
            u.email.toLowerCase().includes(s) || (u.display_name ?? "").toLowerCase().includes(s),
        )
      : list;
    return base.slice(0, 8);
  }, [q, list]);
  return (
    <div className="relative w-full sm:w-72">
      <input
        value={q}
        onChange={(e) => {
          setQ(e.target.value);
          setOpen(true);
        }}
        onFocus={() => setOpen(true)}
        onBlur={() => setTimeout(() => setOpen(false), 150)}
        placeholder={t("downloads.admin.quotaPickPlaceholder")}
        className={inputCls}
      />
      {open && filtered.length > 0 && (
        <div className="absolute z-base mt-1 w-full rounded-lg glass-menu shadow-xl overflow-hidden">
          {filtered.map((u) => (
            <button
              key={u.id}
              onClick={() => {
                onPick({ id: u.id, email: u.email });
                setQ("");
                setOpen(false);
              }}
              className="w-full text-left px-3 py-2 text-sm hover:bg-surface transition flex flex-col"
            >
              <span className="truncate">{u.display_name || u.email}</span>
              {u.display_name && <span className="text-xs text-muted truncate">{u.email}</span>}
            </button>
          ))}
        </div>
      )}
    </div>
  );
}

function AdminSystem() {
  const { t } = useTranslation();
  const storage = useLiveQuery(qk.adminStorage(), api.adminDownloadStorage, { intervalMs: 5000 });
  const jobs = useLiveQuery(qk.adminDownloads(), api.adminDownloads, { intervalMs: 5000 });
  const [quotaFor, setQuotaFor] = useState<{ id: number; email: string } | null>(null);
  const s = storage.data;
  return (
    <div>
      {s && (
        <div className="grid grid-cols-2 sm:grid-cols-4 gap-3 mb-5">
          {[
            [t("downloads.admin.readyFiles"), String(s.ready_files)],
            [t("downloads.admin.totalSize"), formatBytes(s.total_bytes)],
            [
              t("downloads.admin.cap"),
              s.total_cap_bytes ? formatBytes(s.total_cap_bytes) : t("downloads.admin.noCap"),
            ],
          ].map(([label, val]) => (
            <div key={label} className="rounded-xl glass-card p-3">
              <div className="text-xs text-muted">{label}</div>
              <div className="text-lg font-semibold mt-0.5">{val}</div>
            </div>
          ))}
        </div>
      )}

      {s && (
        <div className="mb-6">
          <div className="flex items-center justify-between gap-3 mb-2 flex-wrap">
            <div className="text-sm font-medium">{t("downloads.admin.perUser")}</div>
            {/* Set a quota for any user, regardless of whether they've downloaded anything. */}
            <QuotaUserPicker onPick={setQuotaFor} />
          </div>
          <div className="space-y-1">
            {s.per_user.map((u) => (
              <div
                key={u.user_id}
                className="flex items-center gap-2 text-sm px-3 py-1.5 rounded-lg bg-card/40"
              >
                <span className="flex-1 truncate">{u.email}</span>
                <span className="text-muted">{formatBytes(u.footprint_bytes)}</span>
                <button
                  onClick={() => setQuotaFor({ id: u.user_id, email: u.email ?? "" })}
                  className="p-1 rounded-sm hover:bg-surface text-muted hover:text-fg"
                  title={t("downloads.admin.editQuota")}
                >
                  <Settings2 className="w-4 h-4" />
                </button>
              </div>
            ))}
            {s.per_user.length === 0 && (
              <div className="text-xs text-muted px-3 py-2">{t("downloads.admin.noFootprint")}</div>
            )}
          </div>
        </div>
      )}

      <div className="text-sm font-medium mb-2">{t("downloads.tabs.system")}</div>
      <div className="space-y-1.5">
        {(jobs.data ?? []).map((j) => (
          <div
            key={j.id}
            className="flex items-center gap-3 text-sm px-3 py-1.5 rounded-lg bg-card/40"
          >
            <span className="flex-1 truncate">{jobTitle(j)}</span>
            <span className="text-muted truncate w-40">{j.user_email}</span>
            <StatusPill job={j} />
            <span className="text-muted w-16 text-right">
              {j.asset?.size_bytes ? formatBytes(j.asset.size_bytes) : ""}
            </span>
          </div>
        ))}
        {jobs.data && jobs.data.length === 0 && (
          <div className="text-sm text-muted py-6 text-center">{t("downloads.empty.admin")}</div>
        )}
      </div>

      {quotaFor && (
        <QuotaModal userId={quotaFor.id} email={quotaFor.email} onClose={() => setQuotaFor(null)} />
      )}
    </div>
  );
}

// --- Main -----------------------------------------------------------------------------------

export default function DownloadCenter() {
  const me = useMe();
  const { t } = useTranslation();
  const qc = useQueryClient();
  const confirm = useConfirm();
  // Always land on the queue tab (not a persisted last-tab) — the queue is where new work and
  // any failures are, so it's the useful default every visit.
  const [tab, setTab] = useState("queue");
  const [addUrl, setAddUrl] = useState("");
  const [addSource, setAddSource] = useState<string | null>(null);
  const [manage, setManage] = useState(false);
  const [metaJob, setMetaJob] = useState<DownloadJob | null>(null);
  const [shareJob, setShareJob] = useState<DownloadJob | null>(null);
  const [editJob, setEditJob] = useState<DownloadJob | null>(null);
  const [errorJob, setErrorJob] = useState<DownloadJob | null>(null);

  const jobsQ = useLiveQuery(qk.downloads(), api.downloads, { intervalMs: 2000 });
  const sharedQ = useQuery({
    queryKey: qk.downloadsShared(),
    queryFn: api.downloadsShared,
    enabled: tab === "shared",
  });
  const jobs = jobsQ.data ?? [];
  const queue = jobs.filter((j) => ["queued", "running", "paused", "error"].includes(j.status));
  const library = jobs.filter((j) => j.status === "done");

  const invalidate = () => invalidateDownloads(qc);
  const act = useMutation({
    mutationFn: ({
      id,
      op,
    }: {
      id: number;
      op: "pause" | "resume" | "cancel" | "delete" | "redownload";
    }) =>
      op === "pause"
        ? api.pauseDownload(id)
        : op === "resume"
          ? api.resumeDownload(id)
          : op === "cancel"
            ? api.cancelDownload(id)
            : op === "redownload"
              ? api.redownloadDownload(id)
              : api.deleteDownload(id),
    onSuccess: invalidate,
    // No onError: a failed job action returns 400/409/422/500, already surfaced by the global
    // error modal (api.ts req) with the backend's specific message — a caller toast would double it.
  });

  // Remove a shared-with-me item from your list (only your grant; the owner's file is untouched).
  const removeShared = useMutation({
    mutationFn: (id: number) => api.removeSharedDownload(id),
    onSuccess: () => qc.invalidateQueries({ queryKey: qk.downloadsShared() }),
  });

  const confirmThen = async (title: string, body: string, fn: () => void) => {
    if (await confirm({ title, message: body, confirmLabel: title, danger: true })) fn();
  };

  // Pull a link off the clipboard into the add-URL box. Clipboard reads need a secure context +
  // a user gesture/permission (iOS Safari/Brave are strict) — so this is best-effort: the paste
  // button is an explicit gesture (reliable), and the input's onFocus tries silently (ignored if
  // the browser refuses without a click). Only accept an http(s) URL, don't clobber existing text.
  const pasteFromClipboard = async (force = false) => {
    if (!force && addUrl.trim()) return;
    try {
      const text = (await navigator.clipboard?.readText())?.trim();
      if (text && /^https?:\/\/\S+$/i.test(text)) setAddUrl(text);
    } catch {
      /* permission denied or unsupported — the manual paste button still works on a click */
    }
  };

  const tabs = [
    { id: "queue", label: t("downloads.tabs.queue"), badge: queue.length },
    { id: "done", label: t("downloads.tabs.done"), badge: library.length },
    { id: "shared", label: t("downloads.tabs.shared") },
    ...(me.role === "admin" ? [{ id: "system", label: t("downloads.tabs.system") }] : []),
  ];
  // Guard against the active tab going away under us (e.g. admin on "system" gets demoted mid-session)
  // — that would render a blank page with no active tab. Fall back to the default.
  useEffect(() => {
    if (!tabs.some((tb) => tb.id === tab)) setTab("queue");
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [tab, me.role]);

  const saveBtn = (job: DownloadJob) => (
    <a
      href={api.downloadFileUrl(job.id)}
      title={t("downloads.actions.download")}
      className="p-1.5 rounded-md hover:bg-surface text-muted hover:text-fg transition"
    >
      <Download className="w-4 h-4" />
    </a>
  );

  return (
    <>
      {/* Page title + subtitle + tabs are fixed chrome; the tab content scrolls under them. */}
      <PageToolbar>
        <div className="px-4 pt-3 max-w-4xl w-full mx-auto">
          <div className="flex items-center justify-between gap-3 mb-1">
            <h1 className="text-xl font-semibold">{t("downloads.page.title")}</h1>
            <button
              onClick={() => setManage(true)}
              className="inline-flex items-center gap-1.5 px-2.5 py-1.5 rounded-lg text-sm text-muted hover:text-fg hover:bg-surface transition"
            >
              <Settings2 className="w-4 h-4" /> {t("downloads.page.manage")}
            </button>
          </div>
          <p className="text-sm text-muted mb-4">{t("downloads.page.subtitle")}</p>

          <Tabs tabs={tabs} active={tab} onChange={setTab} />
        </div>
      </PageToolbar>

      <div className="px-4 pb-4 pt-3 max-w-4xl w-full mx-auto">
        {tab === "queue" && (
          <>
            <div className="flex gap-2 mb-4">
              <input
                value={addUrl}
                onChange={(e) => setAddUrl(e.target.value)}
                onFocus={() => pasteFromClipboard()}
                onKeyDown={(e) => e.key === "Enter" && addUrl.trim() && setAddSource(addUrl.trim())}
                placeholder={t("downloads.page.addUrl")}
                className={inputCls}
              />
              <button
                onClick={() => pasteFromClipboard(true)}
                title={t("downloads.page.paste")}
                aria-label={t("downloads.page.paste")}
                className="inline-flex items-center justify-center px-2.5 py-1.5 rounded-lg text-muted hover:text-fg hover:bg-surface transition shrink-0"
              >
                <ClipboardPaste className="w-4 h-4" />
              </button>
              <button
                onClick={() => addUrl.trim() && setAddSource(addUrl.trim())}
                className="inline-flex items-center gap-1.5 px-3 py-1.5 rounded-lg text-sm font-medium bg-accent text-accent-fg hover:opacity-90 transition shrink-0"
              >
                <Plus className="w-4 h-4" /> {t("downloads.page.add")}
              </button>
            </div>
            <div className="space-y-2">
              {queue.map((job) => (
                <DownloadRow key={job.id} job={job} onShowError={setErrorJob}>
                  {(job.status === "queued" || job.status === "running") && (
                    <IconBtn
                      onClick={() => act.mutate({ id: job.id, op: "pause" })}
                      title={t("downloads.actions.pause")}
                    >
                      <Pause className="w-4 h-4" />
                    </IconBtn>
                  )}
                  {(job.status === "paused" || job.status === "error") && (
                    <IconBtn
                      onClick={() => act.mutate({ id: job.id, op: "resume" })}
                      title={t(
                        job.status === "error"
                          ? "downloads.actions.retry"
                          : "downloads.actions.resume",
                      )}
                    >
                      <Play className="w-4 h-4" />
                    </IconBtn>
                  )}
                  <IconBtn
                    onClick={() =>
                      confirmThen(
                        t("downloads.confirm.cancelTitle"),
                        t("downloads.confirm.cancelBody"),
                        () => act.mutate({ id: job.id, op: "cancel" }),
                      )
                    }
                    title={t("downloads.actions.cancel")}
                    danger
                  >
                    <Ban className="w-4 h-4" />
                  </IconBtn>
                </DownloadRow>
              ))}
              {queue.length === 0 &&
                (jobsQ.isError && !jobsQ.data ? (
                  <StateMessage tone="error" onRetry={() => jobsQ.refetch()}>
                    {t("common.loadError")}
                  </StateMessage>
                ) : jobsQ.isLoading ? (
                  <LoadingState />
                ) : (
                  <div className="text-sm text-muted py-10 text-center">
                    {t("downloads.empty.queue")}
                  </div>
                ))}
            </div>
          </>
        )}

        {tab === "done" && (
          <>
            <UsageBar />
            <div className="space-y-2">
              {library.map((job) => (
                <DownloadRow key={job.id} job={job}>
                  {saveBtn(job)}
                  {job.can_download && (job.asset?.duration_s ?? 0) > 0 && (
                    <IconBtn onClick={() => setEditJob(job)} title={t("downloads.actions.edit")}>
                      <Scissors className="w-4 h-4" />
                    </IconBtn>
                  )}
                  <IconBtn
                    onClick={() => setMetaJob(job)}
                    title={t("downloads.actions.editDetails")}
                  >
                    <Pencil className="w-4 h-4" />
                  </IconBtn>
                  <IconBtn onClick={() => setShareJob(job)} title={t("downloads.actions.share")}>
                    <Share2 className="w-4 h-4" />
                  </IconBtn>
                  <IconBtn
                    onClick={() =>
                      confirmThen(
                        t("downloads.confirm.redownloadTitle"),
                        t("downloads.confirm.redownloadBody"),
                        () => act.mutate({ id: job.id, op: "redownload" }),
                      )
                    }
                    title={t("downloads.actions.redownload")}
                  >
                    <RotateCcw className="w-4 h-4" />
                  </IconBtn>
                  <IconBtn
                    onClick={() =>
                      confirmThen(
                        t("downloads.confirm.deleteTitle"),
                        t("downloads.confirm.deleteBody"),
                        () => act.mutate({ id: job.id, op: "delete" }),
                      )
                    }
                    title={t("downloads.actions.delete")}
                    danger
                  >
                    <Trash2 className="w-4 h-4" />
                  </IconBtn>
                </DownloadRow>
              ))}
              {library.length === 0 &&
                (jobsQ.isError && !jobsQ.data ? (
                  <StateMessage tone="error" onRetry={() => jobsQ.refetch()}>
                    {t("common.loadError")}
                  </StateMessage>
                ) : jobsQ.isLoading ? (
                  <LoadingState />
                ) : (
                  <div className="text-sm text-muted py-10 text-center">
                    {t("downloads.empty.done")}
                  </div>
                ))}
            </div>
          </>
        )}

        {tab === "shared" && (
          <div className="space-y-2">
            {(sharedQ.data ?? []).map((job) => (
              <DownloadRow key={job.id} job={job}>
                {job.can_download && saveBtn(job)}
                {job.can_download && (job.asset?.duration_s ?? 0) > 0 && (
                  <IconBtn onClick={() => setEditJob(job)} title={t("downloads.actions.edit")}>
                    <Scissors className="w-4 h-4" />
                  </IconBtn>
                )}
                <IconBtn
                  onClick={() =>
                    confirmThen(
                      t("downloads.confirm.removeSharedTitle"),
                      t("downloads.confirm.removeSharedBody"),
                      () => removeShared.mutate(job.id),
                    )
                  }
                  title={t("downloads.actions.removeShared")}
                  danger
                >
                  <Trash2 className="w-4 h-4" />
                </IconBtn>
              </DownloadRow>
            ))}
            {sharedQ.data && sharedQ.data.length === 0 && (
              <div className="text-sm text-muted py-10 text-center">
                {t("downloads.empty.shared")}
              </div>
            )}
          </div>
        )}

        {tab === "system" && me.role === "admin" && <AdminSystem />}

        <Suspense fallback={null}>
          {addSource && (
            <DownloadDialog
              source={addSource}
              onClose={() => {
                setAddSource(null);
                setAddUrl("");
              }}
            />
          )}
          {manage && <ProfileEditor onClose={() => setManage(false)} />}
          {metaJob && <MetaEditModal job={metaJob} onClose={() => setMetaJob(null)} />}
          {shareJob && <ShareDialog job={shareJob} onClose={() => setShareJob(null)} />}
          {editJob && <VideoEditor job={editJob} onClose={() => setEditJob(null)} />}
          {errorJob && (
            <ErrorModal
              job={errorJob}
              onRetry={() => act.mutate({ id: errorJob.id, op: "resume" })}
              onClose={() => setErrorJob(null)}
            />
          )}
        </Suspense>
      </div>
    </>
  );
}