import { ActionIcon, Button, Group, Menu, Text, ThemeIcon, Tooltip } from "@mantine/core";
import {
  IconArrowRight,
  IconArrowsHorizontal,
  IconClockHour4,
  IconDots,
  IconEye,
  IconEyeOff,
  IconFileExport,
  IconHistory,
  IconLink,
  IconList,
  IconMarkdown,
  IconPrinter,
  IconCloud,
  IconCloudCheck,
  IconStar,
  IconStarFilled,
  IconTrash,
  IconWifiOff,
} from "@tabler/icons-react";
import React, { useEffect, useRef, useState } from "react";
import { useAsideTriggerProps } from "@/hooks/use-toggle-aside.tsx";
import { useAtom, useAtomValue } from "jotai";
import { historyAtoms } from "@/features/page-history/atoms/history-atoms.ts";
import { useDisclosure, useHotkeys } from "@mantine/hooks";
import { useClipboard } from "@/hooks/use-clipboard";
import { useParams } from "react-router-dom";
import { usePageQuery } from "@/features/page/queries/page-query.ts";
import {
  useToggleTemporaryMutation,
  syncTemporaryExpiresInCache,
} from "@/features/page-embed/queries/page-embed-query.ts";
import { buildPageUrl } from "@/features/page/page.utils.ts";
import { notifications } from "@mantine/notifications";
import { getAppUrl } from "@/lib/config.ts";
import { extractPageSlugId } from "@/lib";
import { useTreeMutation } from "@/features/page/tree/hooks/use-tree-mutation.ts";
import { PageWidthToggle } from "@/features/user/components/page-width-pref.tsx";
import { Trans, useTranslation } from "react-i18next";
import ExportModal from "@/components/common/export-modal";
import { htmlToMarkdown } from "@docmost/editor-ext";
import {
  isLocalSyncedAtom,
  isRemoteSyncedAtom,
  pageEditorAtom,
  yjsConnectionStatusAtom,
} from "@/features/editor/atoms/editor-atoms.ts";
import { formattedDate } from "@/lib/time.ts";
import { PageEditModeToggle } from "@/features/user/components/page-state-pref.tsx";
import MovePageModal from "@/features/page/components/move-page-modal.tsx";
import { useTimeAgo } from "@/hooks/use-time-ago.tsx";
import {
  useFavoriteIds,
  useAddFavoriteMutation,
  useRemoveFavoriteMutation,
} from "@/features/favorite/queries/favorite-query";
import {
  useWatchStatusQuery,
  useWatchPageMutation,
  useUnwatchPageMutation,
} from "@/features/page/queries/watcher-query";
import ShareModal from "@/features/share/components/share-modal.tsx";
import { workspaceAtom } from "@/features/user/atoms/current-user-atom.ts";

interface PageHeaderMenuProps {
  readOnly?: boolean;
}
export default function PageHeaderMenu({ readOnly }: PageHeaderMenuProps) {
  const { t } = useTranslation();
  const commentsTriggerProps = useAsideTriggerProps("comments");
  const tocTriggerProps = useAsideTriggerProps("toc");
  const { pageSlug } = useParams();
  const { data: page } = usePageQuery({
    pageId: extractPageSlugId(pageSlug),
  });
  const isDeleted = !!page?.deletedAt;
  const [workspace] = useAtom(workspaceAtom);
  // Community public-sharing entry point (replaces the removed EE PageShareModal)
  const workspaceSharingDisabled = workspace?.settings?.sharing?.disabled === true;

  useHotkeys(
    [
      [
        "mod+F",
        () => {
          const event = new CustomEvent("openFindDialogFromEditor", {});
          document.dispatchEvent(event);
        },
      ],
      [
        "Escape",
        () => {
          const event = new CustomEvent("closeFindDialogFromEditor", {});
          document.dispatchEvent(event);
        },
        { preventDefault: false },
      ],
    ],
    [],
  );

  if (isDeleted) {
    return null;
  }

  return (
    <>
      <ConnectionWarning />

      {!readOnly && <PageEditModeToggle size="xs" />}

      {/* Hide the Share entry point for readers; the toggle inside is inert
          without edit permission, so gate it like other edit-only actions
          (issue #133) */}
      {!readOnly && !workspaceSharingDisabled && (
        <ShareModal readOnly={false} />
      )}

      <Button
        variant="subtle"
        color="dark"
        size="compact-sm"
        {...commentsTriggerProps}
      >
        {t("Comments")}
      </Button>

      <Tooltip label={t("Table of contents")} openDelay={250} withArrow>
        <ActionIcon
          variant="subtle"
          color="dark"
          aria-label={t("Table of contents")}
          {...tocTriggerProps}
        >
          <IconList size={20} stroke={2} />
        </ActionIcon>
      </Tooltip>

      <PageActionMenu readOnly={readOnly} />
    </>
  );
}

interface PageActionMenuProps {
  readOnly?: boolean;
}
function PageActionMenu({ readOnly }: PageActionMenuProps) {
  const { t } = useTranslation();
  const [, setHistoryModalOpen] = useAtom(historyAtoms);
  const clipboard = useClipboard({ timeout: 500 });
  const { pageSlug, spaceSlug } = useParams();
  const { data: page, isLoading } = usePageQuery({
    pageId: extractPageSlugId(pageSlug),
  });
  const { handleDelete } = useTreeMutation(page?.spaceId ?? "");
  const [exportOpened, { open: openExportModal, close: closeExportModal }] =
    useDisclosure(false);
  const [
    movePageModalOpened,
    { open: openMovePageModal, close: closeMoveSpaceModal },
  ] = useDisclosure(false);
  const [pageEditor] = useAtom(pageEditorAtom);
  const pageUpdatedAt = useTimeAgo(page?.updatedAt);
  const favoriteIds = useFavoriteIds("page", page?.spaceId);
  const addFavoriteMutation = useAddFavoriteMutation();
  const removeFavoriteMutation = useRemoveFavoriteMutation();
  const isFavorited = page?.id ? favoriteIds.has(page.id) : false;
  const { data: watchStatus } = useWatchStatusQuery(page?.id);
  const watchPage = useWatchPageMutation();
  const unwatchPage = useUnwatchPageMutation();
  const toggleTemporary = useToggleTemporaryMutation();
  const isTemporary = !!page?.temporaryExpiresAt;

  const handleToggleTemporary = async () => {
    if (!page?.id) return;
    const next = !isTemporary;
    try {
      const res = await toggleTemporary.mutateAsync({
        pageId: page.id,
        temporary: next,
      });
      // Reflect the new deadline in the page cache (menu label + banner) AND in
      // the sidebar tree node so its clock marker updates immediately, no reload.
      syncTemporaryExpiresInCache(page, res.temporaryExpiresAt);
      notifications.show({
        message: next
          ? t("Note will move to trash unless made permanent")
          : t("Note is now permanent"),
      });
    } catch {
      // mutation surfaces the error via notifications
    }
  };

  const handleCopyLink = () => {
    const pageUrl =
      getAppUrl() + buildPageUrl(spaceSlug, page.slugId, page.title);

    clipboard.copy(pageUrl);
    notifications.show({ message: t("Link copied") });
  };

  const handleCopyAsMarkdown = () => {
    if (!pageEditor) return;
    const html = pageEditor.getHTML();
    const markdown = htmlToMarkdown(html);
    const title = page?.title ? `# ${page.title}\n\n` : "";
    clipboard.copy(`${title}${markdown}`);
    notifications.show({ message: t("Copied") });
  };

  const handlePrint = () => {
    setTimeout(() => {
      window.print();
    }, 250);
  };

  const openHistoryModal = () => {
    setHistoryModalOpen(true);
  };

  const handleDeletePage = () => {
    handleDelete(page.id);
  };

  const handleToggleFavorite = () => {
    if (!page?.id) return;
    const params = { type: "page" as const, pageId: page.id };
    if (isFavorited) {
      removeFavoriteMutation.mutate(params);
    } else {
      addFavoriteMutation.mutate(params);
    }
  };

  return (
    <>
      <Menu
        shadow="xl"
        position="bottom-end"
        offset={20}
        width={230}
        withArrow
        arrowPosition="center"
      >
        <Menu.Target>
          <ActionIcon
            variant="subtle"
            color="dark"
            aria-label={t("Page actions")}
          >
            <IconDots size={20} />
          </ActionIcon>
        </Menu.Target>

        <Menu.Dropdown>
          <Menu.Item
            leftSection={<IconLink size={16} />}
            onClick={handleCopyLink}
          >
            {t("Copy link")}
          </Menu.Item>

          <Menu.Item
            leftSection={<IconMarkdown size={16} />}
            onClick={handleCopyAsMarkdown}
          >
            {t("Copy as Markdown")}
          </Menu.Item>

          <Menu.Item
            leftSection={
              isFavorited ? (
                <IconStarFilled size={16} color="var(--mantine-color-yellow-5)" />
              ) : (
                <IconStar size={16} />
              )
            }
            onClick={handleToggleFavorite}
          >
            {isFavorited ? t("Remove from favorites") : t("Add to favorites")}
          </Menu.Item>

          {watchStatus?.watching ? (
            <Menu.Item
              leftSection={<IconEyeOff size={16} />}
              onClick={() => unwatchPage.mutate(page.id)}
            >
              {t("Stop watching")}
            </Menu.Item>
          ) : (
            <Menu.Item
              leftSection={<IconEye size={16} />}
              onClick={() => watchPage.mutate(page.id)}
            >
              {t("Watch page")}
            </Menu.Item>
          )}

          <Menu.Divider />

          <Menu.Item leftSection={<IconArrowsHorizontal size={16} />}>
            <Group wrap="nowrap">
              <PageWidthToggle label={t("Full width")} />
            </Group>
          </Menu.Item>

          <Menu.Item
            leftSection={<IconHistory size={16} />}
            onClick={openHistoryModal}
          >
            {t("Page history")}
          </Menu.Item>

          <Menu.Divider />

          {!readOnly && (
            <Menu.Item
              leftSection={<IconArrowRight size={16} />}
              onClick={openMovePageModal}
            >
              {t("Move to space")}
            </Menu.Item>
          )}

          <Menu.Item
            leftSection={<IconFileExport size={16} />}
            onClick={openExportModal}
          >
            {t("Export")}
          </Menu.Item>

          <Menu.Item
            leftSection={<IconPrinter size={16} />}
            onClick={handlePrint}
          >
            {t("Print PDF")}
          </Menu.Item>

          {!readOnly && (
            <>
              <Menu.Divider />
              <Menu.Item
                leftSection={<IconClockHour4 size={16} />}
                onClick={handleToggleTemporary}
              >
                {isTemporary ? t("Make permanent") : t("Make temporary")}
              </Menu.Item>
              <Menu.Item
                color={"red"}
                leftSection={<IconTrash size={16} />}
                onClick={handleDeletePage}
              >
                {t("Move to trash")}
              </Menu.Item>
            </>
          )}

          <Menu.Divider />

          <>
            <Group px="sm" wrap="nowrap" style={{ cursor: "pointer" }}>
              <Tooltip
                label={t("Edited by {{name}} {{time}}", {
                  name: page.lastUpdatedBy.name,
                  time: pageUpdatedAt,
                })}
                position="left-start"
              >
                <div style={{ width: 210 }}>
                  <Text size="xs" c="dimmed" truncate="end">
                    {t("Word count: {{wordCount}}", {
                      wordCount: pageEditor?.storage?.characterCount?.words(),
                    })}
                  </Text>

                  <Text size="xs" c="dimmed" lineClamp={1}>
                    <Trans
                      defaults="Created by: <b>{{creatorName}}</b>"
                      values={{ creatorName: page?.creator?.name }}
                      components={{ b: <Text span fw={500} /> }}
                    />
                  </Text>
                  <Text size="xs" c="dimmed" truncate="end">
                    {t("Created at: {{time}}", {
                      time: formattedDate(page.createdAt),
                    })}
                  </Text>
                </div>
              </Tooltip>
            </Group>
          </>
        </Menu.Dropdown>
      </Menu>

      <ExportModal
        type="page"
        id={page.id}
        open={exportOpened}
        onClose={closeExportModal}
      />

      <MovePageModal
        pageId={page.id}
        slugId={page.slugId}
        currentSpaceSlug={spaceSlug}
        onClose={closeMoveSpaceModal}
        open={movePageModalOpened}
      />
    </>
  );
}

function ConnectionWarning() {
  const { t } = useTranslation();
  const yjsConnectionStatus = useAtomValue(yjsConnectionStatusAtom);
  const isLocalSynced = useAtomValue(isLocalSyncedAtom);
  const isRemoteSynced = useAtomValue(isRemoteSyncedAtom);
  const [showWarning, setShowWarning] = useState(false);
  const timeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);

  const isDisconnected = ["disconnected", "connecting"].includes(
    yjsConnectionStatus,
  );

  useEffect(() => {
    if (isDisconnected) {
      if (!timeoutRef.current) {
        timeoutRef.current = setTimeout(() => setShowWarning(true), 5000);
      }
    } else {
      if (timeoutRef.current) {
        clearTimeout(timeoutRef.current);
        timeoutRef.current = null;
      }
      setShowWarning(false);
    }
  }, [isDisconnected]);

  // Cleanup only on unmount
  useEffect(() => {
    return () => {
      if (timeoutRef.current) {
        clearTimeout(timeoutRef.current);
      }
    };
  }, []);

  // State (1): offline/disconnected — changes are kept locally. Preserve the
  // existing >5s debounce before surfacing this state.
  if (isDisconnected) {
    if (!showWarning) return null;

    const offlineLabel = t(
      "Offline — changes are saved locally and will sync when you reconnect",
    );
    return (
      <Tooltip label={offlineLabel} openDelay={250} withArrow>
        <ThemeIcon
          variant="default"
          c="red"
          role="status"
          aria-label={offlineLabel}
          style={{ border: "none" }}
        >
          <IconWifiOff size={20} stroke={2} />
        </ThemeIcon>
      </Tooltip>
    );
  }

  // State (2): connected but the remote replica is not fully caught up yet.
  if (!isRemoteSynced || !isLocalSynced) {
    const syncingLabel = t("Syncing changes…");
    return (
      <Tooltip label={syncingLabel} openDelay={250} withArrow>
        <ThemeIcon
          variant="default"
          c="dimmed"
          role="status"
          aria-label={syncingLabel}
          style={{ border: "none" }}
        >
          <IconCloud size={20} stroke={2} />
        </ThemeIcon>
      </Tooltip>
    );
  }

  // State (3): fully synced — subtle confirmation indicator.
  const syncedLabel = t("All changes synced");
  return (
    <Tooltip label={syncedLabel} openDelay={250} withArrow>
      <ThemeIcon
        variant="default"
        c="dimmed"
        role="status"
        aria-label={syncedLabel}
        style={{ border: "none" }}
      >
        <IconCloudCheck size={20} stroke={2} />
      </ThemeIcon>
    </Tooltip>
  );
}