import { useEffect, useState, useRef, useCallback } from "react";
import { createPortal } from "react-dom";
import {
  CAN_REDO_COMMAND,
  CAN_UNDO_COMMAND,
  REDO_COMMAND,
  UNDO_COMMAND,
  SELECTION_CHANGE_COMMAND,
  FORMAT_TEXT_COMMAND,
  FORMAT_ELEMENT_COMMAND,
  $getSelection,
  $isRangeSelection,
  $createParagraphNode,
  $getNodeByKey,
  RangeSelection,
  NodeSelection,
  GridSelection,
} from "lexical";
import {
  INSERT_ORDERED_LIST_COMMAND,
  INSERT_UNORDERED_LIST_COMMAND,
  REMOVE_LIST_COMMAND,
  $isListNode,
  ListNode,
} from "@lexical/list";
import { $isLinkNode, TOGGLE_LINK_COMMAND } from "@lexical/link";
import { useLexicalComposerContext } from "@lexical/react/LexicalComposerContext";
import {
  $isParentElementRTL,
  $wrapNodes,
  $isAtNodeEnd,
} from "@lexical/selection";
import { $getNearestNodeOfType, mergeRegister } from "@lexical/utils";
import {
  $createHeadingNode,
  $createQuoteNode,
  $isHeadingNode,
} from "@lexical/rich-text";
// custom elements
import { FloatingLinkEditor } from "./floating-link-editor";
import { BlockTypeSelect } from "./block-type-select";

const LowPriority = 1;

function getSelectedNode(selection: any) {
  const anchor = selection.anchor;
  const focus = selection.focus;
  const anchorNode = selection.anchor.getNode();
  const focusNode = selection.focus.getNode();
  if (anchorNode === focusNode) {
    return anchorNode;
  }
  const isBackward = selection.isBackward();
  if (isBackward) {
    return $isAtNodeEnd(focus) ? anchorNode : focusNode;
  } else {
    return $isAtNodeEnd(anchor) ? focusNode : anchorNode;
  }
}

export const LexicalToolbar = () => {
  // editor
  const [editor] = useLexicalComposerContext();
  // ref
  const toolbarRef = useRef(null);
  // states
  const [canUndo, setCanUndo] = useState(false);
  const [canRedo, setCanRedo] = useState(false);
  const [blockType, setBlockType] = useState("paragraph");
  const [selectedElementKey, setSelectedElementKey] = useState<string | null>(
    null
  );
  const [isRTL, setIsRTL] = useState(false);
  const [isLink, setIsLink] = useState(false);
  const [isBold, setIsBold] = useState(false);
  const [isItalic, setIsItalic] = useState(false);
  const [isUnderline, setIsUnderline] = useState(false);
  const [isStrikethrough, setIsStrikethrough] = useState(false);
  const [isCode, setIsCode] = useState(false);

  const updateToolbar = useCallback(() => {
    const selection = $getSelection();
    if ($isRangeSelection(selection)) {
      const anchorNode = selection.anchor.getNode();
      const element =
        anchorNode.getKey() === "root"
          ? anchorNode
          : anchorNode.getTopLevelElementOrThrow();
      const elementKey = element.getKey();
      const elementDOM = editor.getElementByKey(elementKey);
      if (elementDOM !== null) {
        setSelectedElementKey(elementKey);
        if ($isListNode(element)) {
          const parentList = $getNearestNodeOfType(anchorNode, ListNode);
          const type = parentList ? parentList.getTag() : element.getTag();
          setBlockType(type);
        } else {
          const type = $isHeadingNode(element)
            ? element.getTag()
            : element.getType();
          setBlockType(type);
        }
      }
      // Update text format
      setIsBold(selection.hasFormat("bold"));
      setIsItalic(selection.hasFormat("italic"));
      setIsUnderline(selection.hasFormat("underline"));
      setIsStrikethrough(selection.hasFormat("strikethrough"));
      setIsRTL($isParentElementRTL(selection));

      // Update links
      const node = getSelectedNode(selection);
      const parent = node.getParent();
      if ($isLinkNode(parent) || $isLinkNode(node)) {
        setIsLink(true);
      } else {
        setIsLink(false);
      }
    }
  }, [editor]);

  useEffect(() => {
    return mergeRegister(
      editor.registerUpdateListener(({ editorState }) => {
        editorState.read(() => {
          updateToolbar();
        });
      }),
      editor.registerCommand(
        SELECTION_CHANGE_COMMAND,
        (_payload, newEditor) => {
          updateToolbar();
          return false;
        },
        LowPriority
      ),
      editor.registerCommand(
        CAN_UNDO_COMMAND,
        (payload) => {
          setCanUndo(payload);
          return false;
        },
        LowPriority
      ),
      editor.registerCommand(
        CAN_REDO_COMMAND,
        (payload) => {
          setCanRedo(payload);
          return false;
        },
        LowPriority
      )
    );
  }, [editor, updateToolbar]);

  const insertLink = useCallback(
    (e: any) => {
      e.preventDefault();
      if (!isLink) {
        editor.dispatchCommand(TOGGLE_LINK_COMMAND, "https://");
      } else {
        editor.dispatchCommand(TOGGLE_LINK_COMMAND, null);
      }
    },
    [editor, isLink]
  );

  return (
    <div
      className="flex items-center mb-1 p-1 w-full flex-wrap border-b "
      ref={toolbarRef}
    >
      <button
        disabled={!canUndo}
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(UNDO_COMMAND, undefined);
        }}
        className="p-2 mr-2"
        aria-label="Undo"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-arrow-counterclockwise"
          viewBox="0 0 16 16"
        >
          <path
            fillRule="evenodd"
            d="M8 3a5 5 0 11-4.546 2.914.5.5 0 00-.908-.417A6 6 0 108 2v1z"
          ></path>
          <path d="M8 4.466V.534a.25.25 0 00-.41-.192L5.23 2.308a.25.25 0 000 .384l2.36 1.966A.25.25 0 008 4.466z"></path>
        </svg>
      </button>
      <button
        disabled={!canRedo}
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(REDO_COMMAND, undefined);
        }}
        className="p-2 mr-2"
        aria-label="Redo"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-arrow-clockwise"
          viewBox="0 0 16 16"
        >
          <path
            fillRule="evenodd"
            d="M8 3a5 5 0 104.546 2.914.5.5 0 01.908-.417A6 6 0 118 2v1z"
          ></path>
          <path d="M8 4.466V.534a.25.25 0 01.41-.192l2.36 1.966c.12.1.12.284 0 .384L8.41 4.658A.25.25 0 018 4.466z"></path>
        </svg>
      </button>
      <BlockTypeSelect
        editor={editor}
        toolbarRef={toolbarRef}
        blockType={blockType}
      />
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_TEXT_COMMAND, "bold");
        }}
        className={`p-2 mr-2 ${isBold ? "active" : ""}`}
        aria-label="Format Bold"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-type-bold"
          viewBox="0 0 16 16"
        >
          <path d="M8.21 13c2.106 0 3.412-1.087 3.412-2.823 0-1.306-.984-2.283-2.324-2.386v-.055a2.176 2.176 0 001.852-2.14c0-1.51-1.162-2.46-3.014-2.46H3.843V13H8.21zM5.908 4.674h1.696c.963 0 1.517.451 1.517 1.244 0 .834-.629 1.32-1.73 1.32H5.908V4.673zm0 6.788V8.598h1.73c1.217 0 1.88.492 1.88 1.415 0 .943-.643 1.449-1.832 1.449H5.907z"></path>
        </svg>
      </button>
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_TEXT_COMMAND, "italic");
        }}
        className={"p-2 mr-2" + (isItalic ? "active" : "")}
        aria-label="Format Italics"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-type-italic"
          viewBox="0 0 16 16"
        >
          <path d="M7.991 11.674L9.53 4.455c.123-.595.246-.71 1.347-.807l.11-.52H7.211l-.11.52c1.06.096 1.128.212 1.005.807L6.57 11.674c-.123.595-.246.71-1.346.806l-.11.52h3.774l.11-.52c-1.06-.095-1.129-.211-1.006-.806z"></path>
        </svg>
      </button>
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_TEXT_COMMAND, "underline");
        }}
        className={"p-2 mr-2" + (isUnderline ? "active" : "")}
        aria-label="Format Underline"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-type-underline"
          viewBox="0 0 16 16"
        >
          <path d="M5.313 3.136h-1.23V9.54c0 2.105 1.47 3.623 3.917 3.623s3.917-1.518 3.917-3.623V3.136h-1.23v6.323c0 1.49-.978 2.57-2.687 2.57-1.709 0-2.687-1.08-2.687-2.57V3.136zM12.5 15h-9v-1h9v1z"></path>
        </svg>
      </button>
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_TEXT_COMMAND, "strikethrough");
        }}
        className={"p-2 mr-2" + (isStrikethrough ? "active" : "")}
        aria-label="Format Strikethrough"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-type-strikethrough"
          viewBox="0 0 16 16"
        >
          <path d="M6.333 5.686c0 .31.083.581.27.814H5.166a2.776 2.776 0 01-.099-.76c0-1.627 1.436-2.768 3.48-2.768 1.969 0 3.39 1.175 3.445 2.85h-1.23c-.11-1.08-.964-1.743-2.25-1.743-1.23 0-2.18.602-2.18 1.607zm2.194 7.478c-2.153 0-3.589-1.107-3.705-2.81h1.23c.144 1.06 1.129 1.703 2.544 1.703 1.34 0 2.31-.705 2.31-1.675 0-.827-.547-1.374-1.914-1.675L8.046 8.5H1v-1h14v1h-3.504c.468.437.675.994.675 1.697 0 1.826-1.436 2.967-3.644 2.967z"></path>
        </svg>
      </button>
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_TEXT_COMMAND, "code");
        }}
        className={"p-2 mr-2 " + (isCode ? "active" : "")}
        aria-label="Insert Code"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-code"
          viewBox="0 0 16 16"
        >
          <path d="M5.854 4.854a.5.5 0 10-.708-.708l-3.5 3.5a.5.5 0 000 .708l3.5 3.5a.5.5 0 00.708-.708L2.707 8l3.147-3.146zm4.292 0a.5.5 0 01.708-.708l3.5 3.5a.5.5 0 010 .708l-3.5 3.5a.5.5 0 01-.708-.708L13.293 8l-3.147-3.146z"></path>
        </svg>
      </button>
      <button
        onClick={insertLink}
        className={"p-2 mr-2 " + (isLink ? "active" : "")}
        aria-label="Insert Link"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-link"
          viewBox="0 0 16 16"
        >
          <path d="M6.354 5.5H4a3 3 0 000 6h3a3 3 0 002.83-4H9c-.086 0-.17.01-.25.031A2 2 0 017 10.5H4a2 2 0 110-4h1.535c.218-.376.495-.714.82-1z"></path>
          <path d="M9 5.5a3 3 0 00-2.83 4h1.098A2 2 0 019 6.5h3a2 2 0 110 4h-1.535a4.02 4.02 0 01-.82 1H12a3 3 0 100-6H9z"></path>
        </svg>
      </button>
      {isLink &&
        createPortal(<FloatingLinkEditor editor={editor} />, document.body)}
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_ELEMENT_COMMAND, "left");
        }}
        className="p-2 mr-2"
        aria-label="Left Align"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-text-left"
          viewBox="0 0 16 16"
        >
          <path
            fillRule="evenodd"
            d="M2 12.5a.5.5 0 01.5-.5h7a.5.5 0 010 1h-7a.5.5 0 01-.5-.5zm0-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5zm0-3a.5.5 0 01.5-.5h7a.5.5 0 010 1h-7a.5.5 0 01-.5-.5zm0-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5z"
          ></path>
        </svg>
      </button>
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_ELEMENT_COMMAND, "center");
        }}
        className="p-2 mr-2"
        aria-label="Center Align"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-text-center"
          viewBox="0 0 16 16"
        >
          <path
            fillRule="evenodd"
            d="M4 12.5a.5.5 0 01.5-.5h7a.5.5 0 010 1h-7a.5.5 0 01-.5-.5zm-2-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5zm2-3a.5.5 0 01.5-.5h7a.5.5 0 010 1h-7a.5.5 0 01-.5-.5zm-2-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5z"
          ></path>
        </svg>
      </button>
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_ELEMENT_COMMAND, "right");
        }}
        className="p-2 mr-2"
        aria-label="Right Align"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-text-right"
          viewBox="0 0 16 16"
        >
          <path
            fillRule="evenodd"
            d="M6 12.5a.5.5 0 01.5-.5h7a.5.5 0 010 1h-7a.5.5 0 01-.5-.5zm-4-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5zm4-3a.5.5 0 01.5-.5h7a.5.5 0 010 1h-7a.5.5 0 01-.5-.5zm-4-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5z"
          ></path>
        </svg>
      </button>
      <button
        onClick={(e) => {
          e.preventDefault();
          editor.dispatchCommand(FORMAT_ELEMENT_COMMAND, "justify");
        }}
        className="p-2 mr-2"
        aria-label="Justify Align"
      >
        <svg
          xmlns="http://www.w3.org/2000/svg"
          width="16"
          height="16"
          fill="currentColor"
          className="bi bi-justify"
          viewBox="0 0 16 16"
        >
          <path
            fillRule="evenodd"
            d="M2 12.5a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5zm0-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5zm0-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5zm0-3a.5.5 0 01.5-.5h11a.5.5 0 010 1h-11a.5.5 0 01-.5-.5z"
          ></path>
        </svg>
      </button>{" "}
    </div>
  );
};