File size: 4,517 Bytes
bc20498
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/**
 * @typedef {import('micromark-util-types').Code} Code
 * @typedef {import('micromark-util-types').Construct} Construct
 * @typedef {import('micromark-util-types').Resolver} Resolver
 * @typedef {import('micromark-util-types').State} State
 * @typedef {import('micromark-util-types').TokenizeContext} TokenizeContext
 * @typedef {import('micromark-util-types').Tokenizer} Tokenizer
 */

import {factorySpace} from 'micromark-factory-space'
import {markdownLineEnding, markdownSpace} from 'micromark-util-character'
/** @type {Construct} */
export const setextUnderline = {
  name: 'setextUnderline',
  tokenize: tokenizeSetextUnderline,
  resolveTo: resolveToSetextUnderline
}

/** @type {Resolver} */
function resolveToSetextUnderline(events, context) {
  // To do: resolve like `markdown-rs`.
  let index = events.length
  /** @type {number | undefined} */
  let content
  /** @type {number | undefined} */
  let text
  /** @type {number | undefined} */
  let definition

  // Find the opening of the content.
  // It’ll always exist: we don’t tokenize if it isn’t there.
  while (index--) {
    if (events[index][0] === 'enter') {
      if (events[index][1].type === 'content') {
        content = index
        break
      }
      if (events[index][1].type === 'paragraph') {
        text = index
      }
    }
    // Exit
    else {
      if (events[index][1].type === 'content') {
        // Remove the content end (if needed we’ll add it later)
        events.splice(index, 1)
      }
      if (!definition && events[index][1].type === 'definition') {
        definition = index
      }
    }
  }
  const heading = {
    type: 'setextHeading',
    start: Object.assign({}, events[text][1].start),
    end: Object.assign({}, events[events.length - 1][1].end)
  }

  // Change the paragraph to setext heading text.
  events[text][1].type = 'setextHeadingText'

  // If we have definitions in the content, we’ll keep on having content,
  // but we need move it.
  if (definition) {
    events.splice(text, 0, ['enter', heading, context])
    events.splice(definition + 1, 0, ['exit', events[content][1], context])
    events[content][1].end = Object.assign({}, events[definition][1].end)
  } else {
    events[content][1] = heading
  }

  // Add the heading exit at the end.
  events.push(['exit', heading, context])
  return events
}

/**
 * @this {TokenizeContext}
 * @type {Tokenizer}
 */
function tokenizeSetextUnderline(effects, ok, nok) {
  const self = this
  /** @type {NonNullable<Code>} */
  let marker
  return start

  /**
   * At start of heading (setext) underline.
   *
   * ```markdown
   *   | aa
   * > | ==
   *     ^
   * ```
   *
   * @type {State}
   */
  function start(code) {
    let index = self.events.length
    /** @type {boolean | undefined} */
    let paragraph
    // Find an opening.
    while (index--) {
      // Skip enter/exit of line ending, line prefix, and content.
      // We can now either have a definition or a paragraph.
      if (
        self.events[index][1].type !== 'lineEnding' &&
        self.events[index][1].type !== 'linePrefix' &&
        self.events[index][1].type !== 'content'
      ) {
        paragraph = self.events[index][1].type === 'paragraph'
        break
      }
    }

    // To do: handle lazy/pierce like `markdown-rs`.
    // To do: parse indent like `markdown-rs`.
    if (!self.parser.lazy[self.now().line] && (self.interrupt || paragraph)) {
      effects.enter('setextHeadingLine')
      marker = code
      return before(code)
    }
    return nok(code)
  }

  /**
   * After optional whitespace, at `-` or `=`.
   *
   * ```markdown
   *   | aa
   * > | ==
   *     ^
   * ```
   *
   * @type {State}
   */
  function before(code) {
    effects.enter('setextHeadingLineSequence')
    return inside(code)
  }

  /**
   * In sequence.
   *
   * ```markdown
   *   | aa
   * > | ==
   *     ^
   * ```
   *
   * @type {State}
   */
  function inside(code) {
    if (code === marker) {
      effects.consume(code)
      return inside
    }
    effects.exit('setextHeadingLineSequence')
    return markdownSpace(code)
      ? factorySpace(effects, after, 'lineSuffix')(code)
      : after(code)
  }

  /**
   * After sequence, after optional whitespace.
   *
   * ```markdown
   *   | aa
   * > | ==
   *       ^
   * ```
   *
   * @type {State}
   */
  function after(code) {
    if (code === null || markdownLineEnding(code)) {
      effects.exit('setextHeadingLine')
      return ok(code)
    }
    return nok(code)
  }
}