import React, { CSSProperties, useCallback, useRef, useEffect } from 'react';
import { useNode, UserComponent } from '@craftjs/core';
import { cssPropsToString } from '../../utils/style-helpers';

type HeadingLevel = 'h1' | 'h2' | 'h3' | 'h4' | 'h5' | 'h6';

// `level` is settable via the AI `update_props` path and from deserialized
// saved state -- neither type-checked at runtime -- and is interpolated
// directly into the tag position (`React.createElement(level, ...)` /
// `<${tag}` in `toHtml`). A malicious value like `h2><img src=x
// onerror=alert(1)` (or a non-h1-6 string) must never reach that position
// unchecked. Anything not in this allowlist clamps to `'h2'`.
const ALLOWED_HEADING_LEVELS = ['h1', 'h2', 'h3', 'h4', 'h5', 'h6'] as const;
const sanitizeHeadingLevel = (level: unknown): HeadingLevel =>
  (ALLOWED_HEADING_LEVELS as readonly unknown[]).includes(level) ? (level as HeadingLevel) : 'h2';

interface HeadingProps {
  text?: string;
  level?: HeadingLevel;
  style?: CSSProperties;
  cssId?: string;
  cssClass?: string;
  hideOnDesktop?: boolean;
  hideOnTablet?: boolean;
  hideOnMobile?: boolean;
  animation?: string;
  animationDelay?: string;
}

export const Heading: UserComponent<HeadingProps> = ({
  text = 'Heading',
  level = 'h2',
  style = {},
}) => {
  const {
    connectors: { connect, drag },
    selected,
    actions: { setProp },
  } = useNode((node) => ({
    selected: node.events.selected,
  }));

  const safeLevel = sanitizeHeadingLevel(level);
  const elRef = useRef<HTMLElement | null>(null);
  const editedTextRef = useRef<string | null>(null);

  const commitText = useCallback(() => {
    if (elRef.current) {
      const newText = elRef.current.innerText;
      editedTextRef.current = newText;
      setProp((p: HeadingProps) => { p.text = newText; });
    }
  }, [setProp]);

  // Commit on blur
  const handleBlur = useCallback(() => { commitText(); }, [commitText]);

  // Also commit on deselect via effect
  useEffect(() => {
    if (!selected && editedTextRef.current !== null) {
      setProp((p: HeadingProps) => { p.text = editedTextRef.current!; });
      editedTextRef.current = null;
    }
  }, [selected, setProp]);

  // Set DOM text on mount and when text prop changes externally (not during editing)
  useEffect(() => {
    if (elRef.current && !selected && editedTextRef.current === null) {
      elRef.current.innerText = text || '';
    }
  }, [text, selected]);

  return React.createElement(safeLevel, {
    ref: (ref: HTMLElement | null): void => {
      elRef.current = ref;
      if (ref) connect(drag(ref));
    },
    contentEditable: selected,
    suppressContentEditableWarning: true,
    onBlur: handleBlur,
    onInput: () => {
      // Track that we have unsaved edits
      if (elRef.current) {
        editedTextRef.current = elRef.current.innerText;
      }
    },
    style: { outline: 'none', cursor: selected ? 'text' : 'pointer', minHeight: '1em', ...style },
  });
};

Heading.craft = {
  displayName: 'Heading',
  props: {
    text: 'Your Heading',
    level: 'h2' as HeadingLevel,
    style: {
      fontSize: '36px',
      fontWeight: '700',
      fontFamily: 'Inter, sans-serif',
      color: '#1f2937',
      marginBottom: '16px',
    },
  },
  rules: {
    canDrag: () => true,
    canMoveIn: () => false,
    canMoveOut: () => true,
  },
};

(Heading as any).toHtml = (props: HeadingProps, _childrenHtml: string) => {
  const tag = sanitizeHeadingLevel(props.level);
  const safeText = (props.text || '').replace(/</g, '&lt;').replace(/>/g, '&gt;');
  const styleStr = cssPropsToString(props.style);
  return { html: `<${tag}${styleStr ? ` style="${styleStr}"` : ''}>${safeText}</${tag}>` };
};