(function (mod) {
  if (typeof exports === 'object' && typeof module === 'object') { // Common JS
    mod(require('../codemirror/lib/codemirror'))
  } else if (typeof define === 'function' && define.amd) { // AMD
    define(['../codemirror/lib/codemirror'], mod)
  } else { // Plain browser env
    mod(CodeMirror)
  }
})(function (CodeMirror) {
  'use strict'

  var listRE = /^(\s*)(>[> ]*|[*+-] \[[x ]\]\s|[*+-]\s|(\d+)([.)]))(\s*)/
  var emptyListRE = /^(\s*)(>[> ]*|[*+-] \[[x ]\]|[*+-]|(\d+)[.)])(\s*)$/
  var unorderedListRE = /[*+-]\s/

  CodeMirror.commands.boostNewLineAndIndentContinueMarkdownList = function (cm) {
    if (cm.getOption('disableInput')) return CodeMirror.Pass
    var ranges = cm.listSelections()
    var replacements = []
    for (var i = 0; i < ranges.length; i++) {
      var pos = ranges[i].head
      var eolState = cm.getStateAfter(pos.line)
      var inList = eolState.list !== false
      var inQuote = eolState.quote !== 0
      var line = cm.getLine(pos.line)
      var match = listRE.exec(line)
      if (!ranges[i].empty() || (!inList && !inQuote) || !match || pos.ch < match[2].length - 1) {
        cm.execCommand('newlineAndIndent')
        return
      }
      if (emptyListRE.test(line)) {
        if (!/>\s*$/.test(line)) {
          cm.replaceRange('', {
            line: pos.line, ch: 0
          }, {
            line: pos.line, ch: pos.ch + 1
          })
        }
        replacements[i] = '\n'
      } else {
        var indent = match[1]
        var after = match[5]
        var bullet = unorderedListRE.test(match[2]) || match[2].indexOf('>') >= 0
          ? match[2].replace('x', ' ')
          : (parseInt(match[3], 10) + 1) + match[4]
        replacements[i] = '\n' + indent + bullet + after

        if (bullet) incrementRemainingMarkdownListNumbers(cm, pos)
      }
    }
    cm.replaceSelections(replacements)
  }
  // Auto-updating Markdown list numbers when a new item is added to the
  // middle of a list
  function incrementRemainingMarkdownListNumbers(cm, pos) {
    var startLine = pos.line, lookAhead = 0, skipCount = 0
    var startItem = listRE.exec(cm.getLine(startLine)), startIndent = startItem[1]

    do {
      lookAhead += 1
      var nextLineNumber = startLine + lookAhead
      var nextLine = cm.getLine(nextLineNumber), nextItem = listRE.exec(nextLine)

      if (nextItem) {
        var nextIndent = nextItem[1]
        var newNumber = (parseInt(startItem[3], 10) + lookAhead - skipCount)
        var nextNumber = (parseInt(nextItem[3], 10)), itemNumber = nextNumber

        if (startIndent === nextIndent && !isNaN(nextNumber)) {
          if (newNumber === nextNumber) itemNumber = nextNumber + 1
          if (newNumber > nextNumber) itemNumber = newNumber + 1
          cm.replaceRange(
            nextLine.replace(listRE, nextIndent + itemNumber + nextItem[4] + nextItem[5]),
          {
            line: nextLineNumber, ch: 0
          }, {
            line: nextLineNumber, ch: nextLine.length
          })
        } else {
          if (startIndent.length > nextIndent.length) return
          // This doesn't run if the next line immediatley indents, as it is
          // not clear of the users intention (new indented item or same level)
          if ((startIndent.length < nextIndent.length) && (lookAhead === 1)) return
          skipCount += 1
        }
      }
    } while (nextItem)
  }
})