'use strict'

module.exports = atxHeading

var lineFeed = '\n'
var tab = '\t'
var space = ' '
var numberSign = '#'

var maxFenceCount = 6

function atxHeading(eat, value, silent) {
  var self = this
  var pedantic = self.options.pedantic
  var length = value.length + 1
  var index = -1
  var now = eat.now()
  var subvalue = ''
  var content = ''
  var character
  var queue
  var depth

  // Eat initial spacing.
  while (++index < length) {
    character = value.charAt(index)

    if (character !== space && character !== tab) {
      index--
      break
    }

    subvalue += character
  }

  // Eat hashes.
  depth = 0

  while (++index <= length) {
    character = value.charAt(index)

    if (character !== numberSign) {
      index--
      break
    }

    subvalue += character
    depth++
  }

  if (depth > maxFenceCount) {
    return
  }

  if (!depth || (!pedantic && value.charAt(index + 1) === numberSign)) {
    return
  }

  length = value.length + 1

  // Eat intermediate white-space.
  queue = ''

  while (++index < length) {
    character = value.charAt(index)

    if (character !== space && character !== tab) {
      index--
      break
    }

    queue += character
  }

  // Exit when not in pedantic mode without spacing.
  if (!pedantic && queue.length === 0 && character && character !== lineFeed) {
    return
  }

  if (silent) {
    return true
  }

  // Eat content.
  subvalue += queue
  queue = ''
  content = ''

  while (++index < length) {
    character = value.charAt(index)

    if (!character || character === lineFeed) {
      break
    }

    if (character !== space && character !== tab && character !== numberSign) {
      content += queue + character
      queue = ''
      continue
    }

    while (character === space || character === tab) {
      queue += character
      character = value.charAt(++index)
    }

    // `#` without a queue is part of the content.
    if (!pedantic && content && !queue && character === numberSign) {
      content += character
      continue
    }

    while (character === numberSign) {
      queue += character
      character = value.charAt(++index)
    }

    while (character === space || character === tab) {
      queue += character
      character = value.charAt(++index)
    }

    index--
  }

  now.column += subvalue.length
  now.offset += subvalue.length
  subvalue += content + queue

  return eat(subvalue)({
    type: 'heading',
    depth: depth,
    children: self.tokenizeInline(content, now)
  })
}