import React, {
  useCallback, useState, FC, useEffect, ReactNode,
} from 'react';

import nodePath from 'path';

import { pathUtils, pagePathUtils, Nullable } from '@growi/core';
import { useTranslation } from 'next-i18next';
import Link from 'next/link';
import { useDrag, useDrop } from 'react-dnd';
import { UncontrolledTooltip, DropdownToggle } from 'reactstrap';

import { bookmark, unbookmark, resumeRenameOperation } from '~/client/services/page-operation';
import { toastWarning, toastError, toastSuccess } from '~/client/util/apiNotification';
import { apiv3Put, apiv3Post } from '~/client/util/apiv3-client';
import TriangleIcon from '~/components/Icons/TriangleIcon';
import { NotAvailableForGuest } from '~/components/NotAvailableForGuest';
import {
  IPageHasId, IPageInfoAll, IPageToDeleteWithMeta,
} from '~/interfaces/page';
import { useSWRBookmarkInfo, useSWRxCurrentUserBookmarks } from '~/stores/bookmark';
import { IPageForPageDuplicateModal } from '~/stores/modal';
import { useSWRxPageChildren } from '~/stores/page-listing';
import { usePageTreeDescCountMap } from '~/stores/ui';
import loggerFactory from '~/utils/logger';
import { shouldRecoverPagePaths } from '~/utils/page-operation';

import ClosableTextInput, { AlertInfo, AlertType } from '../../Common/ClosableTextInput';
import CountBadge from '../../Common/CountBadge';
import { PageItemControl } from '../../Common/Dropdown/PageItemControl';

import { ItemNode } from './ItemNode';


const logger = loggerFactory('growi:cli:Item');


interface ItemProps {
  isEnableActions: boolean
  itemNode: ItemNode
  targetPathOrId?: Nullable<string>
  isOpen?: boolean
  isEnabledAttachTitleHeader?: boolean
  onRenamed?(fromPath: string | undefined, toPath: string): void
  onClickDuplicateMenuItem?(pageToDuplicate: IPageForPageDuplicateModal): void
  onClickDeleteMenuItem?(pageToDelete: IPageToDeleteWithMeta): void
}

// Utility to mark target
const markTarget = (children: ItemNode[], targetPathOrId?: Nullable<string>): void => {
  if (targetPathOrId == null) {
    return;
  }

  children.forEach((node) => {
    if (node.page._id === targetPathOrId || node.page.path === targetPathOrId) {
      node.page.isTarget = true;
    }
    return node;
  });
};

/**
 * Return new page path after the droppedPagePath is moved under the newParentPagePath
 * @param droppedPagePath
 * @param newParentPagePath
 * @returns
 */
const getNewPathAfterMoved = (droppedPagePath: string, newParentPagePath: string): string => {
  const pageTitle = nodePath.basename(droppedPagePath);
  return nodePath.join(newParentPagePath, pageTitle);
};

/**
 * Return whether the fromPage could be moved under the newParentPage
 * @param fromPage
 * @param newParentPage
 * @param printLog
 * @returns
 */
const isDroppable = (fromPage?: Partial<IPageHasId>, newParentPage?: Partial<IPageHasId>, printLog = false): boolean => {
  if (fromPage == null || newParentPage == null || fromPage.path == null || newParentPage.path == null) {
    if (printLog) {
      logger.warn('Any of page, page.path or droppedPage.path is null');
    }
    return false;
  }

  const newPathAfterMoved = getNewPathAfterMoved(fromPage.path, newParentPage.path);
  return pagePathUtils.canMoveByPath(fromPage.path, newPathAfterMoved) && !pagePathUtils.isUsersTopPage(newParentPage.path);
};

// Component wrapper to make a child element not draggable
// https://github.com/react-dnd/react-dnd/issues/335
type NotDraggableProps = {
  children: ReactNode,
};
const NotDraggableForClosableTextInput = (props: NotDraggableProps): JSX.Element => {
  return <div draggable onDragStart={e => e.preventDefault()}>{props.children}</div>;
};


const Item: FC<ItemProps> = (props: ItemProps) => {
  const { t } = useTranslation();
  const {
    itemNode, targetPathOrId, isOpen: _isOpen = false, isEnabledAttachTitleHeader,
    onRenamed, onClickDuplicateMenuItem, onClickDeleteMenuItem, isEnableActions,
  } = props;

  const { page, children } = itemNode;

  const [currentChildren, setCurrentChildren] = useState(children);
  const [isOpen, setIsOpen] = useState(_isOpen);
  const [isNewPageInputShown, setNewPageInputShown] = useState(false);
  const [shouldHide, setShouldHide] = useState(false);
  const [isRenameInputShown, setRenameInputShown] = useState(false);
  const [isCreating, setCreating] = useState(false);

  const { data, mutate: mutateChildren } = useSWRxPageChildren(isOpen ? page._id : null);
  const { mutate: mutateCurrentUserBookmarks } = useSWRxCurrentUserBookmarks();
  const { mutate: mutateBookmarkInfo } = useSWRBookmarkInfo(page._id);

  // descendantCount
  const { getDescCount } = usePageTreeDescCountMap();
  const descendantCount = getDescCount(page._id) || page.descendantCount || 0;


  // hasDescendants flag
  const isChildrenLoaded = currentChildren?.length > 0;
  const hasDescendants = descendantCount > 0 || isChildrenLoaded;

  // to re-show hidden item when useDrag end() callback
  const displayDroppedItemByPageId = useCallback((pageId) => {
    const target = document.getElementById(`pagetree-item-${pageId}`);
    if (target == null) {
      return;
    }

    // wait 500ms to avoid removing before d-none is set by useDrag end() callback
    setTimeout(() => {
      target.classList.remove('d-none');
    }, 500);
  }, []);

  const [, drag] = useDrag({
    type: 'PAGE_TREE',
    item: { page },
    canDrag: () => {
      if (page.path == null) {
        return false;
      }
      return !pagePathUtils.isUsersProtectedPages(page.path);
    },
    end: (item, monitor) => {
      // in order to set d-none to dropped Item
      const dropResult = monitor.getDropResult();
      if (dropResult != null) {
        setShouldHide(true);
      }
    },
    collect: monitor => ({
      isDragging: monitor.isDragging(),
      canDrag: monitor.canDrag(),
    }),
  });

  const pageItemDropHandler = async(item: ItemNode) => {
    const { page: droppedPage } = item;

    if (!isDroppable(droppedPage, page, true)) {
      return;
    }

    if (droppedPage.path == null || page.path == null) {
      return;
    }

    const newPagePath = getNewPathAfterMoved(droppedPage.path, page.path);

    try {
      await apiv3Put('/pages/rename', {
        pageId: droppedPage._id,
        revisionId: droppedPage.revision,
        newPagePath,
        isRenameRedirect: false,
        updateMetadata: true,
      });

      await mutateChildren();

      if (onRenamed != null) {
        onRenamed(page.path, newPagePath);
      }

      // force open
      setIsOpen(true);
    }
    catch (err) {
      // display the dropped item
      displayDroppedItemByPageId(droppedPage._id);

      if (err.code === 'operation__blocked') {
        toastWarning(t('pagetree.you_cannot_move_this_page_now'));
      }
      else {
        toastError(t('pagetree.something_went_wrong_with_moving_page'));
      }
    }
  };

  const [{ isOver }, drop] = useDrop<ItemNode, Promise<void>, { isOver: boolean }>(() => ({
    accept: 'PAGE_TREE',
    drop: pageItemDropHandler,
    hover: (item, monitor) => {
      // when a drag item is overlapped more than 1 sec, the drop target item will be opened.
      if (monitor.isOver()) {
        setTimeout(() => {
          if (monitor.isOver()) {
            setIsOpen(true);
          }
        }, 600);
      }
    },
    canDrop: (item) => {
      const { page: droppedPage } = item;
      return isDroppable(droppedPage, page);
    },
    collect: monitor => ({
      isOver: monitor.isOver(),
    }),
  }));

  const hasChildren = useCallback((): boolean => {
    return currentChildren != null && currentChildren.length > 0;
  }, [currentChildren]);

  const onClickLoadChildren = useCallback(async() => {
    setIsOpen(!isOpen);
  }, [isOpen]);

  const onClickPlusButton = useCallback(() => {
    setNewPageInputShown(true);

    if (hasDescendants) {
      setIsOpen(true);
    }
  }, [hasDescendants]);

  const bookmarkMenuItemClickHandler = async(_pageId: string, _newValue: boolean): Promise<void> => {
    const bookmarkOperation = _newValue ? bookmark : unbookmark;
    await bookmarkOperation(_pageId);
    mutateCurrentUserBookmarks();
    mutateBookmarkInfo();
  };

  const duplicateMenuItemClickHandler = useCallback((): void => {
    if (onClickDuplicateMenuItem == null) {
      return;
    }

    const { _id: pageId, path } = page;

    if (pageId == null || path == null) {
      throw Error('Any of _id and path must not be null.');
    }

    const pageToDuplicate = { pageId, path };

    onClickDuplicateMenuItem(pageToDuplicate);
  }, [onClickDuplicateMenuItem, page]);

  const renameMenuItemClickHandler = useCallback(() => {
    setRenameInputShown(true);
  }, []);

  const onPressEnterForRenameHandler = async(inputText: string) => {
    const parentPath = pathUtils.addTrailingSlash(nodePath.dirname(page.path ?? ''));
    const newPagePath = nodePath.resolve(parentPath, inputText);

    if (newPagePath === page.path) {
      setRenameInputShown(false);
      return;
    }

    try {
      setRenameInputShown(false);
      await apiv3Put('/pages/rename', {
        pageId: page._id,
        revisionId: page.revision,
        newPagePath,
      });

      if (onRenamed != null) {
        onRenamed(page.path, newPagePath);
      }

      toastSuccess(t('renamed_pages', { path: page.path }));
    }
    catch (err) {
      setRenameInputShown(true);
      toastError(err);
    }
  };

  const deleteMenuItemClickHandler = useCallback(async(_pageId: string, pageInfo: IPageInfoAll | undefined): Promise<void> => {
    if (onClickDeleteMenuItem == null) {
      return;
    }

    if (page._id == null || page.path == null) {
      throw Error('_id and path must not be null.');
    }

    const pageToDelete: IPageToDeleteWithMeta = {
      data: {
        _id: page._id,
        revision: page.revision as string,
        path: page.path,
      },
      meta: pageInfo,
    };

    onClickDeleteMenuItem(pageToDelete);
  }, [onClickDeleteMenuItem, page]);

  const onPressEnterForCreateHandler = async(inputText: string) => {
    setNewPageInputShown(false);
    const parentPath = pathUtils.addTrailingSlash(page.path as string);
    const newPagePath = nodePath.resolve(parentPath, inputText);
    const isCreatable = pagePathUtils.isCreatablePage(newPagePath);

    if (!isCreatable) {
      toastWarning(t('you_can_not_create_page_with_this_name'));
      return;
    }

    let initBody = '';
    if (isEnabledAttachTitleHeader) {
      const pageTitle = nodePath.basename(newPagePath);
      initBody = pathUtils.attachTitleHeader(pageTitle);
    }

    try {
      setCreating(true);

      await apiv3Post('/pages/', {
        path: newPagePath,
        body: initBody,
        grant: page.grant,
        grantUserGroupId: page.grantedGroup,
        createFromPageTree: true,
      });

      mutateChildren();

      if (!hasDescendants) {
        setIsOpen(true);
      }

      toastSuccess(t('successfully_saved_the_page'));
    }
    catch (err) {
      toastError(err);
    }
    finally {
      setCreating(false);
    }
  };

  const inputValidator = (title: string | null): AlertInfo | null => {
    if (title == null || title === '' || title.trim() === '') {
      return {
        type: AlertType.WARNING,
        message: t('form_validation.title_required'),
      };
    }

    return null;
  };

  /**
   * Users do not need to know if all pages have been renamed.
   * Make resuming rename operation appears to be working fine to allow users for a seamless operation.
   */
  const pathRecoveryMenuItemClickHandler = async(pageId: string): Promise<void> => {
    try {
      await resumeRenameOperation(pageId);
      toastSuccess(t('page_operation.paths_recovered'));
    }
    catch {
      toastError(t('page_operation.path_recovery_failed'));
    }
  };

  // didMount
  useEffect(() => {
    if (hasChildren()) setIsOpen(true);
  }, [hasChildren]);

  /*
   * Make sure itemNode.children and currentChildren are synced
   */
  useEffect(() => {
    if (children.length > currentChildren.length) {
      markTarget(children, targetPathOrId);
      setCurrentChildren(children);
    }
  }, [children, currentChildren.length, targetPathOrId]);

  /*
   * When swr fetch succeeded
   */
  useEffect(() => {
    if (isOpen && data != null) {
      const newChildren = ItemNode.generateNodesFromPages(data.children);
      markTarget(newChildren, targetPathOrId);
      setCurrentChildren(newChildren);
    }
  }, [data, isOpen, targetPathOrId]);

  // Rename process
  // Icon that draw attention from users for some actions
  const shouldShowAttentionIcon = page.processData != null ? shouldRecoverPagePaths(page.processData) : false;

  return (
    <div
      id={`pagetree-item-${page._id}`}
      data-testid="grw-pagetree-item-container"
      className={`grw-pagetree-item-container ${isOver ? 'grw-pagetree-is-over' : ''}
    ${shouldHide ? 'd-none' : ''}`}
    >
      <li
        ref={(c) => { drag(c); drop(c) }}
        className={`list-group-item list-group-item-action border-0 py-0 pr-3 d-flex align-items-center
        ${page.isTarget ? 'grw-pagetree-current-page-item' : ''}`}
        id={page.isTarget ? 'grw-pagetree-current-page-item' : `grw-pagetree-list-${page._id}`}
      >
        <div className="grw-triangle-container d-flex justify-content-center">
          {hasDescendants && (
            <button
              type="button"
              className={`grw-pagetree-triangle-btn btn ${isOpen ? 'grw-pagetree-open' : ''}`}
              onClick={onClickLoadChildren}
            >
              <div className="d-flex justify-content-center">
                <TriangleIcon />
              </div>
            </button>
          )}
        </div>
        { isRenameInputShown
          ? (
            <div className="flex-fill">
              <NotDraggableForClosableTextInput>
                <ClosableTextInput
                  value={nodePath.basename(page.path ?? '')}
                  placeholder={t('Input page name')}
                  onClickOutside={() => { setRenameInputShown(false) }}
                  onPressEnter={onPressEnterForRenameHandler}
                  inputValidator={inputValidator}
                />
              </NotDraggableForClosableTextInput>
            </div>
          )
          : (
            <>
              { shouldShowAttentionIcon && (
                <>
                  <i id="path-recovery" className="fa fa-warning mr-2 text-warning"></i>
                  <UncontrolledTooltip placement="top" target="path-recovery" fade={false}>
                    {t('tooltip.operation.attention.rename')}
                  </UncontrolledTooltip>
                </>
              )}
              { page != null && page.path != null && page._id != null && (
                <Link href={pathUtils.returnPathForURL(page.path, page._id)} prefetch={false}>
                  <a className="grw-pagetree-title-anchor flex-grow-1">
                    <p className={`text-truncate m-auto ${page.isEmpty && 'grw-sidebar-text-muted'}`}>{nodePath.basename(page.path ?? '') || '/'}</p>
                  </a>
                </Link>
              )}
            </>
          )}
        {descendantCount > 0 && !isRenameInputShown && (
          <div className="grw-pagetree-count-wrapper">
            <CountBadge count={descendantCount} />
          </div>
        )}
        <NotAvailableForGuest>
          <div className="grw-pagetree-control d-flex">
            <PageItemControl
              pageId={page._id}
              isEnableActions={isEnableActions}
              onClickBookmarkMenuItem={bookmarkMenuItemClickHandler}
              onClickDuplicateMenuItem={duplicateMenuItemClickHandler}
              onClickRenameMenuItem={renameMenuItemClickHandler}
              onClickDeleteMenuItem={deleteMenuItemClickHandler}
              onClickPathRecoveryMenuItem={pathRecoveryMenuItemClickHandler}
              isInstantRename
              // Todo: It is wanted to find a better way to pass operationProcessData to PageItemControl
              operationProcessData={page.processData}
            >
              {/* pass the color property to reactstrap dropdownToggle props. https://6-4-0--reactstrap.netlify.app/components/dropdowns/  */}
              <DropdownToggle color="transparent" className="border-0 rounded btn-page-item-control p-0 grw-visible-on-hover mr-1">
                <i id='option-button-in-page-tree' className="icon-options fa fa-rotate-90 p-1"></i>
              </DropdownToggle>
            </PageItemControl>
          </div>
        </NotAvailableForGuest>

        {!pagePathUtils.isUsersTopPage(page.path ?? '') && (
          <NotAvailableForGuest>
            <button
              id='page-create-button-in-page-tree'
              type="button"
              className="border-0 rounded btn btn-page-item-control p-0 grw-visible-on-hover"
              onClick={onClickPlusButton}
            >
              <i className="icon-plus d-block p-0" />
            </button>
          </NotAvailableForGuest>
        )}
      </li>

      {isEnableActions && isNewPageInputShown && (
        <div className="flex-fill">
          <NotDraggableForClosableTextInput>
            <ClosableTextInput
              placeholder={t('Input page name')}
              onClickOutside={() => { setNewPageInputShown(false) }}
              onPressEnter={onPressEnterForCreateHandler}
              inputValidator={inputValidator}
            />
          </NotDraggableForClosableTextInput>
        </div>
      )}
      {
        isOpen && hasChildren() && currentChildren.map((node, index) => (
          <div key={node.page._id} className="grw-pagetree-item-children">
            <Item
              isEnableActions={isEnableActions}
              itemNode={node}
              isOpen={false}
              targetPathOrId={targetPathOrId}
              isEnabledAttachTitleHeader={isEnabledAttachTitleHeader}
              onRenamed={onRenamed}
              onClickDuplicateMenuItem={onClickDuplicateMenuItem}
              onClickDeleteMenuItem={onClickDeleteMenuItem}
            />
            { isCreating && (currentChildren.length - 1 === index) && (
              <div className="text-muted text-center">
                <i className="fa fa-spinner fa-pulse mr-1"></i>
              </div>
            )}
          </div>
        ))
      }
    </div>
  );

};

export default Item;
