Loki/frontend/node_modules/micromark-factory-destination/dev/index.js

/**
 * @import {Effects, State, TokenType} from 'micromark-util-types'
 */

import {
  asciiControl,
  markdownLineEndingOrSpace,
  markdownLineEnding
} from 'micromark-util-character'
import {codes, constants, types} from 'micromark-util-symbol'

/**
 * Parse destinations.
 *
 * ###### Examples
 *
 * ```markdown
 * <a>
 * <a\>b>
 * <a b>
 * <a)>
 * a
 * a\)b
 * a(b)c
 * a(b)
 * ```
 *
 * @param {Effects} effects
 *   Context.
 * @param {State} ok
 *   State switched to when successful.
 * @param {State} nok
 *   State switched to when unsuccessful.
 * @param {TokenType} type
 *   Type for whole (`<a>` or `b`).
 * @param {TokenType} literalType
 *   Type when enclosed (`<a>`).
 * @param {TokenType} literalMarkerType
 *   Type for enclosing (`<` and `>`).
 * @param {TokenType} rawType
 *   Type when not enclosed (`b`).
 * @param {TokenType} stringType
 *   Type for the value (`a` or `b`).
 * @param {number | undefined} [max=Infinity]
 *   Depth of nested parens (inclusive).
 * @returns {State}
 *   Start state.
 */
export function factoryDestination(
  effects,
  ok,
  nok,
  type,
  literalType,
  literalMarkerType,
  rawType,
  stringType,
  max
) {
  const limit = max || Number.POSITIVE_INFINITY
  let balance = 0

  return start

  /**
   * Start of destination.
   *
   * ```markdown
   * > | <aa>
   *     ^
   * > | aa
   *     ^
   * ```
   *
   * @type {State}
   */
  function start(code) {
    if (code === codes.lessThan) {
      effects.enter(type)
      effects.enter(literalType)
      effects.enter(literalMarkerType)
      effects.consume(code)
      effects.exit(literalMarkerType)
      return enclosedBefore
    }

    // ASCII control, space, closing paren.
    if (
      code === codes.eof ||
      code === codes.space ||
      code === codes.rightParenthesis ||
      asciiControl(code)
    ) {
      return nok(code)
    }

    effects.enter(type)
    effects.enter(rawType)
    effects.enter(stringType)
    effects.enter(types.chunkString, {contentType: constants.contentTypeString})
    return raw(code)
  }

  /**
   * After `<`, at an enclosed destination.
   *
   * ```markdown
   * > | <aa>
   *      ^
   * ```
   *
   * @type {State}
   */
  function enclosedBefore(code) {
    if (code === codes.greaterThan) {
      effects.enter(literalMarkerType)
      effects.consume(code)
      effects.exit(literalMarkerType)
      effects.exit(literalType)
      effects.exit(type)
      return ok
    }

    effects.enter(stringType)
    effects.enter(types.chunkString, {contentType: constants.contentTypeString})
    return enclosed(code)
  }

  /**
   * In enclosed destination.
   *
   * ```markdown
   * > | <aa>
   *      ^
   * ```
   *
   * @type {State}
   */
  function enclosed(code) {
    if (code === codes.greaterThan) {
      effects.exit(types.chunkString)
      effects.exit(stringType)
      return enclosedBefore(code)
    }

    if (
      code === codes.eof ||
      code === codes.lessThan ||
      markdownLineEnding(code)
    ) {
      return nok(code)
    }

    effects.consume(code)
    return code === codes.backslash ? enclosedEscape : enclosed
  }

  /**
   * After `\`, at a special character.
   *
   * ```markdown
   * > | <a\*a>
   *        ^
   * ```
   *
   * @type {State}
   */
  function enclosedEscape(code) {
    if (
      code === codes.lessThan ||
      code === codes.greaterThan ||
      code === codes.backslash
    ) {
      effects.consume(code)
      return enclosed
    }

    return enclosed(code)
  }

  /**
   * In raw destination.
   *
   * ```markdown
   * > | aa
   *     ^
   * ```
   *
   * @type {State}
   */
  function raw(code) {
    if (
      !balance &&
      (code === codes.eof ||
        code === codes.rightParenthesis ||
        markdownLineEndingOrSpace(code))
    ) {
      effects.exit(types.chunkString)
      effects.exit(stringType)
      effects.exit(rawType)
      effects.exit(type)
      return ok(code)
    }

    if (balance < limit && code === codes.leftParenthesis) {
      effects.consume(code)
      balance++
      return raw
    }

    if (code === codes.rightParenthesis) {
      effects.consume(code)
      balance--
      return raw
    }

    // ASCII control (but *not* `\0`) and space and `(`.
    // Note: in `markdown-rs`, `\0` exists in codes, in `micromark-js` it
    // doesn’t.
    if (
      code === codes.eof ||
      code === codes.space ||
      code === codes.leftParenthesis ||
      asciiControl(code)
    ) {
      return nok(code)
    }

    effects.consume(code)
    return code === codes.backslash ? rawEscape : raw
  }

  /**
   * After `\`, at special character.
   *
   * ```markdown
   * > | a\*a
   *       ^
   * ```
   *
   * @type {State}
   */
  function rawEscape(code) {
    if (
      code === codes.leftParenthesis ||
      code === codes.rightParenthesis ||
      code === codes.backslash
    ) {
      effects.consume(code)
      return raw
    }

    return raw(code)
  }
}