class GitLabDropdownFilter
  BLUR_KEYCODES = [27, 40]

  constructor: (@dropdown, @remote, @data, @callback) ->
    @input = @dropdown.find(".dropdown-input-field")

    # Key events
    @input.on "keyup", (e) =>
      blur_field = @shouldBlur e.keyCode
      search_text = @input.val()

      if blur_field
        @input.blur()

      if @remote
        @remote search_text, (data) =>
          @callback(data)
      else
        @filter search_text

  shouldBlur: (keyCode) ->
    return BLUR_KEYCODES.indexOf(keyCode) >= 0

  filter: (search_text) ->
    data = @data()
    results = if search_text isnt "" then data.search(search_text) else data.list

    @callback results

class GitLabDropdownRemote
  constructor: (@dataEndpoint, @options) ->

  execute: ->
    if typeof @dataEndpoint is "string"
      @fetchData()
    else if typeof @dataEndpoint is "function"
      if @options.beforeSend
        @options.beforeSend()

      # Fetch the data by calling the data funcfion
      @dataEndpoint (data) =>
        if @options.success
          @options.success(data)

        if @options.beforeSend
          @options.beforeSend()

  # Fetch the data through ajax if the data is a string
  fetchData: ->
    $.ajax(
      url: @dataEndpoint,
      dataType: @options.dataType,
      beforeSend: =>
        if @options.beforeSend
          @options.beforeSend()
      success: (data) =>
        if @options.success
          @options.success(data)
    )

class GitLabDropdown
  LOADING_CLASS = "is-loading"

  constructor: (@el, @options) ->
    self = @
    @dropdown = $(@el).parent()
    search_fields = if @options.search then @options.search.fields else [];

    if @options.data
      # Remote data
      @remote = new GitLabDropdownRemote @options.data, {
        dataType: @options.dataType,
        beforeSend: @toggleLoading.bind(@)
        success: (data) =>
          @fullData = data
          dataToPrase = @fullData

          if @options.filterable
            @fullData = new Fuse data, {
              keys: search_fields
            }
            dataToPrase = @fullData.list

          @parseData dataToPrase
      }

    # Init filiterable
    if @options.filterable
      @filter = new GitLabDropdownFilter @dropdown, @options.query, =>
        return @fullData
      , (data) =>
        @parseData data

    # Event listeners
    $(@el).parent().on "shown.bs.dropdown", @opened

    if @options.selectable
      @dropdown.on "click", "a", (e) ->
        self.rowClicked $(@)

        if self.options.clicked
          self.options.clicked()

  toggleLoading: ->
    $('.dropdown-menu', @dropdown).toggleClass LOADING_CLASS

  parseData: (data) ->
    @renderedData = data

    # Render each row
    html = $.map data, (obj) =>
      return @renderItem(obj)

    if @options.filterable and data.length is 0
      # render no matching results
      html = [@noResults()]

    # Render the full menu
    full_html = @renderMenu(html.join(""))

    @appendMenu(full_html)

  opened: =>
    if @remote
      @remote.execute()

  # Render the full menu
  renderMenu: (html) ->
    menu_html = ""

    if @options.renderMenu
      menu_html = @options.renderMenu(html)
    else
      menu_html = "<ul>#{html}</ul>"

    return menu_html

  # Append the menu into the dropdown
  appendMenu: (html) ->
    $('.dropdown-content', @dropdown).html html

  # Render the row
  renderItem: (data) ->
    html = ""

    if @options.renderRow
      # Call the render function
      html = @options.renderRow(data)
    else
      selected = if @options.isSelected then @options.isSelected(data) else false
      url = if @options.url then @options.url(data) else ""
      text = if @options.text then @options.text(data) else ""
      cssClass = "";

      if selected
        cssClass = "is-active"

      html = "<li>"
      html += "<a href='#{url}' class='#{cssClass}'>"
      html += text
      html += "</a>"
      html += "</li>"

    return html

  noResults: ->
    html = "<li>"
    html += "<a href='#' class='is-focused'>"
    html += "No matching results."
    html += "</a>"
    html += "</li>"

  rowClicked: (el) ->
    fieldName = @options.fieldName
    selectedIndex = el.parent().index()
    selectedObject = @renderedData[selectedIndex]
    value = if @options.id then @options.id(selectedObject) else selectedObject.id

    if @options.multiSelect
      fieldName = "[#{fieldName}]"
    else
      @dropdown.find('.is-active').removeClass 'is-active'
      @dropdown.parent().find("input[name='#{fieldName}']").remove()

    # Toggle active class for the tick mark
    el.toggleClass "is-active"

    if value isnt 0
      # Create hidden input for form
      input = "<input type='hidden' name='#{fieldName}' value='#{value}' />"
      @dropdown.before input

$.fn.glDropdown = (opts) ->
  return @.each ->
    new GitLabDropdown @, opts