'use client'

import type { Editor } from '@tiptap/react'
import * as React from 'react'
// --- Icons ---
import { HeadingIcon } from '~/components/tiptap/tiptap-icons/heading-icon'
// --- Tiptap UI ---
import {
  canToggle,
  headingIcons,
  isHeadingActive,
  type Level,
  shouldShowButton,
} from '~/components/tiptap/tiptap-ui/heading-button'
// --- Hooks ---
import { useTiptapEditor } from '~/hooks/use-tiptap-editor'

/**
 * Configuration for the heading dropdown menu functionality
 */
export interface UseHeadingDropdownMenuConfig {
  /**
   * The Tiptap editor instance.
   */
  editor?: Editor | null
  /**
   * Available heading levels to show in the dropdown
   * @default [1, 2, 3, 4, 5, 6]
   */
  levels?: Level[]
  /**
   * Whether the dropdown should hide when headings are not available.
   * @default false
   */
  hideWhenUnavailable?: boolean
}

/**
 * Gets the currently active heading level from the available levels
 */
export function getActiveHeadingLevel(
  editor: Editor | null,
  levels: Level[] = [1, 2, 3, 4, 5, 6],
): Level | undefined {
  if (!editor || !editor.isEditable) return undefined
  return levels.find((level) => isHeadingActive(editor, level))
}

/**
 * Custom hook that provides heading dropdown menu functionality for Tiptap editor
 *
 * @example
 * ```tsx
 * // Simple usage
 * function MyHeadingDropdown() {
 *   const {
 *     isVisible,
 *     activeLevel,
 *     isAnyHeadingActive,
 *     canToggle,
 *     levels,
 *   } = useHeadingDropdownMenu()
 *
 *   if (!isVisible) return null
 *
 *   return (
 *     <DropdownMenu>
 *       // dropdown content
 *     </DropdownMenu>
 *   )
 * }
 *
 * // Advanced usage with configuration
 * function MyAdvancedHeadingDropdown() {
 *   const {
 *     isVisible,
 *     activeLevel,
 *   } = useHeadingDropdownMenu({
 *     editor: myEditor,
 *     levels: [1, 2, 3],
 *     hideWhenUnavailable: true,
 *   })
 *
 *   // component implementation
 * }
 * ```
 */
export function useHeadingDropdownMenu(config?: UseHeadingDropdownMenuConfig) {
  const {
    editor: providedEditor,
    levels = [1, 2, 3, 4, 5, 6],
    hideWhenUnavailable = false,
  } = config || {}

  const { editor } = useTiptapEditor(providedEditor)
  const [isVisible, setIsVisible] = React.useState(true)

  const activeLevel = getActiveHeadingLevel(editor, levels)
  const isActive = isHeadingActive(editor)
  const canToggleState = canToggle(editor)

  React.useEffect(() => {
    if (!editor) return

    const handleSelectionUpdate = () => {
      setIsVisible(shouldShowButton({ editor, hideWhenUnavailable, level: levels }))
    }

    handleSelectionUpdate()

    editor.on('selectionUpdate', handleSelectionUpdate)

    return () => {
      editor.off('selectionUpdate', handleSelectionUpdate)
    }
  }, [editor, hideWhenUnavailable, levels])

  return {
    isVisible,
    activeLevel,
    isActive,
    canToggle: canToggleState,
    levels,
    label: 'Heading',
    Icon: activeLevel ? headingIcons[activeLevel] : HeadingIcon,
  }
}