import type {
  Data,
  Parent,
  BlockContent,
  DefinitionContent,
  PhrasingContent
} from 'mdast'

export {directiveFromMarkdown, directiveToMarkdown} from './lib/index.js'

/**
 * Fields shared by directives.
 */
interface DirectiveFields {
  /**
   * Directive name.
   */
  name: string

  /**
   * Directive attributes.
   */
  attributes?: Record<string, string | null | undefined> | null | undefined
}

/**
 * Markdown directive (container form).
 */
export interface ContainerDirective extends Parent, DirectiveFields {
  /**
   * Node type of container directive.
   */
  type: 'containerDirective'

  /**
   * Children of container directive.
   */
  children: Array<BlockContent | DefinitionContent>

  /**
   * Data associated with the mdast container directive.
   */
  data?: ContainerDirectiveData | undefined
}

/**
 * Info associated with mdast container directive nodes by the ecosystem.
 */
export interface ContainerDirectiveData extends Data {}

/**
 * Markdown directive (leaf form).
 */
export interface LeafDirective extends Parent, DirectiveFields {
  /**
   * Node type of leaf directive.
   */
  type: 'leafDirective'

  /**
   * Children of leaf directive.
   */
  children: PhrasingContent[]

  /**
   * Data associated with the mdast leaf directive.
   */
  data?: LeafDirectiveData | undefined
}

/**
 * Info associated with mdast leaf directive nodes by the ecosystem.
 */
export interface LeafDirectiveData extends Data {}

/**
 * Markdown directive (text form).
 */
export interface TextDirective extends Parent, DirectiveFields {
  /**
   * Node type of text directive.
   */
  type: 'textDirective'

  /**
   * Children of text directive.
   */
  children: PhrasingContent[]

  /**
   * Data associated with the text leaf directive.
   */
  data?: TextDirectiveData | undefined
}

/**
 * Info associated with mdast text directive nodes by the ecosystem.
 */
export interface TextDirectiveData extends Data {}

/**
 * Union of registered mdast directive nodes.
 *
 * It is not possible to register custom mdast directive node types.
 */
export type Directives = ContainerDirective | LeafDirective | TextDirective

// Add custom data tracked to turn markdown into a tree.
declare module 'mdast-util-from-markdown' {
  interface CompileData {
    /**
     * Attributes for current directive.
     */
    directiveAttributes?: Array<[string, string]> | undefined
  }
}

// Add custom data tracked to turn a syntax tree into markdown.
declare module 'mdast-util-to-markdown' {
  interface ConstructNameMap {
    /**
     * Whole container directive.
     *
     * ```markdown
     * > | :::a
     *     ^^^^
     * > | :::
     *     ^^^
     * ```
     */
    containerDirective: 'containerDirective'

    /**
     * Label of a container directive.
     *
     * ```markdown
     * > | :::a[b]
     *         ^^^
     *   | :::
     * ```
     */
    containerDirectiveLabel: 'containerDirectiveLabel'

    /**
     * Whole leaf directive.
     *
     * ```markdown
     * > | ::a
     *     ^^^
     * ```
     */
    leafDirective: 'leafDirective'

    /**
     * Label of a leaf directive.
     *
     * ```markdown
     * > | ::a[b]
     *        ^^^
     * ```
     */
    leafDirectiveLabel: 'leafDirectiveLabel'

    /**
     * Whole text directive.
     *
     * ```markdown
     * > | :a
     *     ^^
     * ```
     */
    textDirective: 'textDirective'

    /**
     * Label of a text directive.
     *
     * ```markdown
     * > | :a[b]
     *       ^^^
     * ```
     */
    textDirectiveLabel: 'textDirectiveLabel'
  }
}

// Add nodes to content, register `data` on paragraph.
declare module 'mdast' {
  interface BlockContentMap {
    /**
     * Directive in flow content (such as in the root document, or block
     * quotes), which contains further flow content.
     */
    containerDirective: ContainerDirective

    /**
     * Directive in flow content (such as in the root document, or block
     * quotes), which contains nothing.
     */
    leafDirective: LeafDirective
  }

  interface ParagraphData {
    /**
     * Field set on the first paragraph which is a child of a container
     * directive.
     * When this is `true`, that means the paragraph represents the *label*:
     *
     * ```markdown
     * :::a[This is the label]
     * This is further things.
     * :::
     * ```
     */
    directiveLabel?: boolean | null | undefined
  }

  interface PhrasingContentMap {
    /**
     * Directive in phrasing content (such as in paragraphs, headings).
     */
    textDirective: TextDirective
  }

  interface RootContentMap {
    /**
     * Directive in flow content (such as in the root document, or block
     * quotes), which contains further flow content.
     */
    containerDirective: ContainerDirective

    /**
     * Directive in flow content (such as in the root document, or block
     * quotes), which contains nothing.
     */
    leafDirective: LeafDirective

    /**
     * Directive in phrasing content (such as in paragraphs, headings).
     */
    textDirective: TextDirective
  }
}