'use strict'

var markdownLineEndingOrSpace = require('../character/markdown-line-ending-or-space.js')
var chunkedPush = require('../util/chunked-push.js')
var chunkedSplice = require('../util/chunked-splice.js')
var normalizeIdentifier = require('../util/normalize-identifier.js')
var resolveAll = require('../util/resolve-all.js')
var shallow = require('../util/shallow.js')
var factoryDestination = require('./factory-destination.js')
var factoryLabel = require('./factory-label.js')
var factoryTitle = require('./factory-title.js')
var factoryWhitespace = require('./factory-whitespace.js')

var labelEnd = {
  name: 'labelEnd',
  tokenize: tokenizeLabelEnd,
  resolveTo: resolveToLabelEnd,
  resolveAll: resolveAllLabelEnd
}
var resourceConstruct = {
  tokenize: tokenizeResource
}
var fullReferenceConstruct = {
  tokenize: tokenizeFullReference
}
var collapsedReferenceConstruct = {
  tokenize: tokenizeCollapsedReference
}

function resolveAllLabelEnd(events) {
  var index = -1
  var token

  while (++index < events.length) {
    token = events[index][1]

    if (
      !token._used &&
      (token.type === 'labelImage' ||
        token.type === 'labelLink' ||
        token.type === 'labelEnd')
    ) {
      // Remove the marker.
      events.splice(index + 1, token.type === 'labelImage' ? 4 : 2)
      token.type = 'data'
      index++
    }
  }

  return events
}

function resolveToLabelEnd(events, context) {
  var index = events.length
  var offset = 0
  var group
  var label
  var text
  var token
  var open
  var close
  var media // Find an opening.

  while (index--) {
    token = events[index][1]

    if (open) {
      // If we see another link, or inactive link label, we’ve been here before.
      if (
        token.type === 'link' ||
        (token.type === 'labelLink' && token._inactive)
      ) {
        break
      } // Mark other link openings as inactive, as we can’t have links in
      // links.

      if (events[index][0] === 'enter' && token.type === 'labelLink') {
        token._inactive = true
      }
    } else if (close) {
      if (
        events[index][0] === 'enter' &&
        (token.type === 'labelImage' || token.type === 'labelLink') &&
        !token._balanced
      ) {
        open = index

        if (token.type !== 'labelLink') {
          offset = 2
          break
        }
      }
    } else if (token.type === 'labelEnd') {
      close = index
    }
  }

  group = {
    type: events[open][1].type === 'labelLink' ? 'link' : 'image',
    start: shallow(events[open][1].start),
    end: shallow(events[events.length - 1][1].end)
  }
  label = {
    type: 'label',
    start: shallow(events[open][1].start),
    end: shallow(events[close][1].end)
  }
  text = {
    type: 'labelText',
    start: shallow(events[open + offset + 2][1].end),
    end: shallow(events[close - 2][1].start)
  }
  media = [
    ['enter', group, context],
    ['enter', label, context]
  ] // Opening marker.

  media = chunkedPush(media, events.slice(open + 1, open + offset + 3)) // Text open.

  media = chunkedPush(media, [['enter', text, context]]) // Between.

  media = chunkedPush(
    media,
    resolveAll(
      context.parser.constructs.insideSpan.null,
      events.slice(open + offset + 4, close - 3),
      context
    )
  ) // Text close, marker close, label close.

  media = chunkedPush(media, [
    ['exit', text, context],
    events[close - 2],
    events[close - 1],
    ['exit', label, context]
  ]) // Reference, resource, or so.

  media = chunkedPush(media, events.slice(close + 1)) // Media close.

  media = chunkedPush(media, [['exit', group, context]])
  chunkedSplice(events, open, events.length, media)
  return events
}

function tokenizeLabelEnd(effects, ok, nok) {
  var self = this
  var index = self.events.length
  var labelStart
  var defined // Find an opening.

  while (index--) {
    if (
      (self.events[index][1].type === 'labelImage' ||
        self.events[index][1].type === 'labelLink') &&
      !self.events[index][1]._balanced
    ) {
      labelStart = self.events[index][1]
      break
    }
  }

  return start

  function start(code) {
    if (!labelStart) {
      return nok(code)
    } // It’s a balanced bracket, but contains a link.

    if (labelStart._inactive) return balanced(code)
    defined =
      self.parser.defined.indexOf(
        normalizeIdentifier(
          self.sliceSerialize({
            start: labelStart.end,
            end: self.now()
          })
        )
      ) > -1
    effects.enter('labelEnd')
    effects.enter('labelMarker')
    effects.consume(code)
    effects.exit('labelMarker')
    effects.exit('labelEnd')
    return afterLabelEnd
  }

  function afterLabelEnd(code) {
    // Resource: `[asd](fgh)`.
    if (code === 40) {
      return effects.attempt(
        resourceConstruct,
        ok,
        defined ? ok : balanced
      )(code)
    } // Collapsed (`[asd][]`) or full (`[asd][fgh]`) reference?

    if (code === 91) {
      return effects.attempt(
        fullReferenceConstruct,
        ok,
        defined
          ? effects.attempt(collapsedReferenceConstruct, ok, balanced)
          : balanced
      )(code)
    } // Shortcut reference: `[asd]`?

    return defined ? ok(code) : balanced(code)
  }

  function balanced(code) {
    labelStart._balanced = true
    return nok(code)
  }
}

function tokenizeResource(effects, ok, nok) {
  return start

  function start(code) {
    effects.enter('resource')
    effects.enter('resourceMarker')
    effects.consume(code)
    effects.exit('resourceMarker')
    return factoryWhitespace(effects, open)
  }

  function open(code) {
    if (code === 41) {
      return end(code)
    }

    return factoryDestination(
      effects,
      destinationAfter,
      nok,
      'resourceDestination',
      'resourceDestinationLiteral',
      'resourceDestinationLiteralMarker',
      'resourceDestinationRaw',
      'resourceDestinationString',
      3
    )(code)
  }

  function destinationAfter(code) {
    return markdownLineEndingOrSpace(code)
      ? factoryWhitespace(effects, between)(code)
      : end(code)
  }

  function between(code) {
    if (code === 34 || code === 39 || code === 40) {
      return factoryTitle(
        effects,
        factoryWhitespace(effects, end),
        nok,
        'resourceTitle',
        'resourceTitleMarker',
        'resourceTitleString'
      )(code)
    }

    return end(code)
  }

  function end(code) {
    if (code === 41) {
      effects.enter('resourceMarker')
      effects.consume(code)
      effects.exit('resourceMarker')
      effects.exit('resource')
      return ok
    }

    return nok(code)
  }
}

function tokenizeFullReference(effects, ok, nok) {
  var self = this
  return start

  function start(code) {
    return factoryLabel.call(
      self,
      effects,
      afterLabel,
      nok,
      'reference',
      'referenceMarker',
      'referenceString'
    )(code)
  }

  function afterLabel(code) {
    return self.parser.defined.indexOf(
      normalizeIdentifier(
        self.sliceSerialize(self.events[self.events.length - 1][1]).slice(1, -1)
      )
    ) < 0
      ? nok(code)
      : ok(code)
  }
}

function tokenizeCollapsedReference(effects, ok, nok) {
  return start

  function start(code) {
    effects.enter('reference')
    effects.enter('referenceMarker')
    effects.consume(code)
    effects.exit('referenceMarker')
    return open
  }

  function open(code) {
    if (code === 93) {
      effects.enter('referenceMarker')
      effects.consume(code)
      effects.exit('referenceMarker')
      effects.exit('reference')
      return ok
    }

    return nok(code)
  }
}

module.exports = labelEnd