import type { DOMOutputSpec, Node as ProsemirrorNode } from 'prosemirror-model'

import type { ListAttributes } from '../types'

/**
 * @public @group Schema
 */
export interface ListToDOMOptions {
  /**
   * The list node to be rendered.
   */
  node: ProsemirrorNode

  /**
   * If `true`, the list will be rendered as a native `<ul>` or `<ol>` element.
   * You might want to use {@link joinListElements} to join the list elements
   * afterward.
   *
   * @defaultValue false
   */
  nativeList?: boolean

  /**
   * An optional function to get elements inside `<div class="list-marker">`.
   * Return `null` to hide the marker.
   */
  getMarkers?: (node: ProsemirrorNode) => DOMOutputSpec[] | null

  /**
   * An optional function to get the attributes added to HTML element.
   */
  getAttributes?: (node: ProsemirrorNode) => Record<string, string | undefined>
}

/**
 * Renders a list node to DOM output spec.
 *
 * @public @group Schema
 */
export function listToDOM(options: ListToDOMOptions): DOMOutputSpec {
  const {
    node,
    nativeList = false,
    getMarkers = defaultMarkerGetter,
    getAttributes = defaultAttributesGetter,
  } = options
  const attrs = node.attrs as ListAttributes
  const markerHidden = node.firstChild?.type === node.type
  const markers = markerHidden ? null : getMarkers(node)
  const domAttrs = getAttributes(node)
  const contentContainer: DOMOutputSpec = ['div', { class: 'list-content' }, 0]
  const markerContainer: DOMOutputSpec | null = markers && [
    'div',
    {
      class: 'list-marker list-marker-click-target',
      // Set `contenteditable` to `false` so that the cursor won't be
      // moved into the mark container when clicking on it.
      contenteditable: 'false',
    },
    ...markers,
  ]

  if (nativeList) {
    const listTag = attrs.kind === 'ordered' ? 'ol' : 'ul'
    if (markerContainer) {
      return [listTag, ['li', domAttrs, markerContainer, contentContainer]]
    } else {
      return [listTag, ['li', domAttrs, 0]]
    }
  } else {
    if (markerContainer) {
      return ['div', domAttrs, markerContainer, contentContainer]
    } else {
      return ['div', domAttrs, contentContainer]
    }
  }
}

/** @internal */
export function defaultMarkerGetter(
  node: ProsemirrorNode,
): DOMOutputSpec[] | null {
  const attrs = node.attrs as ListAttributes
  switch (attrs.kind) {
    case 'task':
      // Use a `label` element here so that the area around the checkbox is also checkable.
      return [
        [
          'label',
          [
            'input',
            { type: 'checkbox', checked: attrs.checked ? '' : undefined },
          ],
        ],
      ]
    case 'toggle':
      return []
    default:
      return null
  }
}

/** @internal */
export function defaultAttributesGetter(node: ProsemirrorNode) {
  const attrs = node.attrs as ListAttributes
  const markerHidden = node.firstChild?.type === node.type
  const markerType = markerHidden ? undefined : attrs.kind || 'bullet'
  const domAttrs = {
    class: 'prosemirror-flat-list',
    'data-list-kind': markerType,
    'data-list-order': attrs.order != null ? String(attrs.order) : undefined,
    'data-list-checked': attrs.checked ? '' : undefined,
    'data-list-collapsed': attrs.collapsed ? '' : undefined,
    'data-list-collapsable': node.childCount >= 2 ? '' : undefined,
    style:
      attrs.order != null
        ? `--prosemirror-flat-list-order: ${attrs.order};`
        : undefined,
  }

  return domAttrs
}