import { ArrowLeft, Clock, File as FileIcon, Folder, LoaderCircle, RotateCcw, Trash, Trash2 } from "lucide-react";
import { useMemo, useState } from "react";
import { Link } from "react-router";
import { toast } from "sonner";
import { useSession } from "~/api/auth.ts";
import {
  type FileRef,
  filesErrorText,
  filesMockEnabled,
  type TrashItem,
  useFileRoots,
  usePurge,
  useRestore,
  useTrash,
} from "~/api/files.ts";
import { ConfirmDialog } from "~/components/console/confirm-dialog.tsx";
import { type DataColumn, DataTable } from "~/components/console/data-table.tsx";
import { PageHeader } from "~/components/console/page-header.tsx";
import { StatusBadge } from "~/components/console/status-badge.tsx";
import { DirTree } from "~/components/files/dir-tree.tsx";
import { Checkbox } from "~/components/files/file-list.tsx";
import { baseName, newIdempotencyKey } from "~/components/files/model.ts";
import { Button, buttonVariants } from "~/components/ui/button.tsx";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "~/components/ui/dialog.tsx";
import { Input } from "~/components/ui/input.tsx";
import { relTime } from "~/components/workbench/release-fields.ts";
import { formatBytes, formatDateTime } from "~/lib/utils.ts";

const DAY = 86_400_000;

function expiryTone(iso: string): "destructive" | "warning" | "neutral" {
  const left = Date.parse(iso) - Date.now();
  if (left <= 0) return "destructive";
  if (left < DAY) return "warning";
  return "neutral";
}

export default function FilesTrashPage() {
  const trash = useTrash();
  const roots = useFileRoots();
  const session = useSession();
  const isAdmin = session.data?.actor?.type === "admin";
  const restore = useRestore();
  const purge = usePurge();
  const [picked, setPicked] = useState<Set<string>>(new Set());
  const [restoreTo, setRestoreTo] = useState<string[] | null>(null);
  const [purgeAll, setPurgeAll] = useState(false);
  const [purgeIds, setPurgeIds] = useState<string[] | null>(null);
  const [confirmText, setConfirmText] = useState("");
  const rows = trash.data?.pages.flatMap((p) => p.items);
  const rootName = useMemo(() => new Map((roots.data ?? []).map((r) => [r.id, r])), [roots.data]);
  const expired = rows?.filter((r) => Date.parse(r.expiresAt) <= Date.now()) ?? [];

  const toggle = (id: string) =>
    setPicked((p) => {
      const n = new Set(p);
      if (n.has(id)) n.delete(id);
      else n.add(id);
      return n;
    });

  const doRestore = (ids: string[], target?: FileRef) =>
    restore.mutate(
      { idempotencyKey: newIdempotencyKey(), ids, target },
      {
        onSuccess: (r) => {
          setPicked(new Set());
          setRestoreTo(null);
          if (r.restored.length) toast.success(`已还原 ${r.restored.length} 项`);
          for (const f of r.failed)
            toast.error(
              f.code === "exists" || f.code === "conflict" ? "原位置已被占用,可用“还原到…”换个目录" : f.message,
              { description: rows?.find((x) => x.id === f.id)?.originalPath },
            );
        },
        onError: (e) => toast.error(filesErrorText(e, "还原失败")),
      },
    );

  const doPurge = (ids?: string[]) =>
    purge
      .mutateAsync({ idempotencyKey: newIdempotencyKey(), ids })
      .then((r) => {
        setPicked(new Set());
        toast.success(`已清除 ${r.purged.length} 项${r.failed.length ? `,${r.failed.length} 项失败` : ""}`);
      })
      .catch((e) => {
        toast.error(filesErrorText(e, "清除失败"));
        throw e;
      });

  const columns: DataColumn<TrashItem>[] = [
    {
      key: "pick",
      header: (
        <Checkbox
          checked={!!rows?.length && picked.size === rows.length}
          partial={picked.size > 0 && picked.size < (rows?.length ?? 0)}
          label="全选"
          onToggle={() => setPicked(picked.size === rows?.length ? new Set() : new Set(rows?.map((r) => r.id)))}
        />
      ),
      className: "w-10",
      cell: (r) => (
        <Checkbox checked={picked.has(r.id)} label={`选择 ${baseName(r.originalPath)}`} onToggle={() => toggle(r.id)} />
      ),
    },
    {
      key: "name",
      header: "原位置",
      cell: (r) => {
        const root = rootName.get(r.rootId);
        const snap = r.assetSnapshot as { title?: string; contentUnit?: string | null } | null;
        return (
          <div className="flex min-w-0 max-w-lg items-start gap-2">
            {r.isDir ? (
              <Folder className="mt-0.5 h-4 w-4 shrink-0 text-muted-foreground" />
            ) : (
              <FileIcon className="mt-0.5 h-4 w-4 shrink-0 text-muted-foreground" />
            )}
            <div className="min-w-0">
              <p className="truncate text-foreground" title={r.originalPath}>
                {baseName(r.originalPath)}
              </p>
              <p className="truncate font-mono text-meta text-muted-foreground" title={r.trashPath}>
                {root?.name ?? r.rootId} / {r.originalPath}
              </p>
              {snap?.title ? (
                <p className="text-meta text-muted-foreground">
                  删除时关联:{snap.title}
                  {snap.contentUnit ? ` ${snap.contentUnit}` : ""}(还原不会自动恢复资产)
                </p>
              ) : null}
            </div>
          </div>
        );
      },
    },
    {
      key: "size",
      header: "大小",
      hideBelow: "sm",
      align: "right",
      cell: (r) => <span className="whitespace-nowrap">{formatBytes(r.size, 1)}</span>,
    },
    {
      key: "deleted",
      header: "删除",
      hideBelow: "md",
      cell: (r) => (
        <span
          className="block max-w-40 text-muted-foreground"
          title={`${formatDateTime(r.deletedAt)}${r.actor ? ` · ${r.actor}` : ""}`}
        >
          <span className="block whitespace-nowrap">{relTime(r.deletedAt)}</span>
          {r.actor ? (
            <span className="block truncate text-meta">{r.actor.replace(/^admin_session:/, "管理员 ")}</span>
          ) : null}
        </span>
      ),
    },
    {
      key: "expires",
      header: "到期清除",
      cell: (r) => (
        <span title={formatDateTime(r.expiresAt)}>
          <StatusBadge tone={expiryTone(r.expiresAt)}>
            {Date.parse(r.expiresAt) <= Date.now() ? "已到期" : relTime(r.expiresAt)}
          </StatusBadge>
        </span>
      ),
    },
    {
      key: "act",
      header: <span className="sr-only">操作</span>,
      align: "right",
      cell: (r) => (
        <div className="flex justify-end gap-1">
          <Button size="xs" variant="outline" onClick={() => doRestore([r.id])} disabled={restore.isPending}>
            <RotateCcw />
            还原
          </Button>
          <Button size="xs" variant="ghost" onClick={() => setRestoreTo([r.id])}>
            还原到…
          </Button>
          {isAdmin ? (
            <Button
              size="xs"
              variant="ghost"
              aria-label="立即清除"
              title="立即清除"
              onClick={() => setPurgeIds([r.id])}
            >
              <Trash2 />
            </Button>
          ) : null}
        </div>
      ),
    },
  ];

  return (
    <>
      <PageHeader
        title="回收站"
        description="删除的文件先移到这里,保留 7 天后由后台任务清除;期间可还原到原位置或其他目录。"
        actions={
          <>
            {filesMockEnabled() ? <StatusBadge tone="warning">演示数据</StatusBadge> : null}
            <Link to="/console/files" className={buttonVariants({ variant: "outline", size: "sm" })}>
              <ArrowLeft />
              文件
            </Link>
          </>
        }
      />
      <div className="mb-4 flex flex-wrap items-center gap-2">
        <Button
          size="sm"
          variant="outline"
          disabled={!picked.size || restore.isPending}
          onClick={() => doRestore([...picked])}
        >
          {restore.isPending ? <LoaderCircle className="animate-spin" /> : <RotateCcw />}
          还原选中 {picked.size || ""}
        </Button>
        {isAdmin ? (
          <>
            <Button size="sm" variant="outline" disabled={!picked.size} onClick={() => setPurgeIds([...picked])}>
              <Trash2 />
              清除选中
            </Button>
            <ConfirmDialog
              trigger={
                <Button size="sm" variant="outline" disabled={!expired.length}>
                  <Clock />
                  清除已到期 {expired.length || ""}
                </Button>
              }
              title="清除已到期的项?"
              description={`${expired.length} 项已过保留期,清除后不可恢复。`}
              confirmLabel="清除"
              destructive
              onConfirm={() => doPurge(undefined)}
            />
            <Button
              size="sm"
              variant="destructive"
              className="ml-auto"
              disabled={!rows?.length}
              onClick={() => setPurgeAll(true)}
            >
              <Trash />
              清空回收站
            </Button>
          </>
        ) : (
          <span className="ml-auto text-meta text-muted-foreground">立即清除仅管理员会话可用。</span>
        )}
      </div>
      <DataTable
        columns={columns}
        rows={rows}
        rowKey={(r) => r.id}
        loading={trash.isPending}
        error={trash.error}
        onRetry={() => void trash.refetch()}
        hasMore={trash.hasNextPage}
        onLoadMore={() => void trash.fetchNextPage()}
        loadingMore={trash.isFetchingNextPage}
        empty={{ icon: Trash2, title: "回收站是空的", description: "在文件页删除的项会先移到这里。" }}
      />

      <ConfirmDialog
        open={!!purgeIds}
        onOpenChange={(o) => !o && setPurgeIds(null)}
        title={`立即清除 ${purgeIds?.length ?? 0} 项?`}
        description="清除后不可恢复。"
        confirmLabel="清除"
        destructive
        onConfirm={() => doPurge(purgeIds ?? undefined).then(() => setPurgeIds(null))}
      />

      {/* 清空全部:二次确认,需输入“清空回收站” */}
      <ConfirmDialog
        open={purgeAll}
        onOpenChange={(o) => {
          setPurgeAll(o);
          if (!o) setConfirmText("");
        }}
        title="清空回收站?"
        description={`将立即清除全部 ${rows?.length ?? 0} 项(含未到期的),不可恢复。`}
        confirmLabel="清空"
        destructive
        onConfirm={() => {
          if (confirmText.trim() !== "清空回收站") {
            toast.error("请输入“清空回收站”确认");
            return Promise.reject(new Error("unconfirmed"));
          }
          return doPurge(rows?.map((r) => r.id)).then(() => setConfirmText(""));
        }}
      >
        <Input
          value={confirmText}
          onChange={(e) => setConfirmText(e.target.value)}
          placeholder="输入 清空回收站"
          aria-label="输入 清空回收站 以确认"
        />
      </ConfirmDialog>

      {restoreTo ? (
        <RestoreToDialog
          ids={restoreTo}
          onClose={() => setRestoreTo(null)}
          onPick={(t) => doRestore(restoreTo, t)}
          pending={restore.isPending}
        />
      ) : null}
    </>
  );
}

function RestoreToDialog({
  ids,
  onClose,
  onPick,
  pending,
}: {
  ids: string[];
  onClose: () => void;
  onPick: (t: FileRef) => void;
  pending: boolean;
}) {
  const roots = useFileRoots();
  const [target, setTarget] = useState<FileRef | null>(null);
  return (
    <Dialog open onOpenChange={(o) => !o && onClose()}>
      <DialogContent className="sm:max-w-lg">
        <DialogHeader>
          <DialogTitle>还原到…</DialogTitle>
          <DialogDescription>{ids.length} 项 · 选一个可写的目录;同名已存在的项会失败,不会覆盖。</DialogDescription>
        </DialogHeader>
        <div className="max-h-80 overflow-y-auto rounded-xl border border-border p-1.5">
          <DirTree roots={roots.data ?? []} current={target} onSelect={setTarget} pickOnly />
        </div>
        <DialogFooter>
          <Button variant="outline" onClick={onClose}>
            取消
          </Button>
          <Button disabled={!target || pending} onClick={() => target && onPick(target)}>
            {pending ? <LoaderCircle className="animate-spin" /> : <RotateCcw />}
            还原到这里
          </Button>
        </DialogFooter>
      </DialogContent>
    </Dialog>
  );
}