throw new Error("repeated setting on "+key)

    if @keyForSetting.has(setting.value)

      throw new Error("repeated keyForSetting on "+setting.value)

    @settings.set(key, {

      setting: setting,

      onChangeFunc: @onChanged[key],

      jsValue: value

    })

    @keyForSetting.set(setting.value, key)

    if @onChanged[key]?

      @onChanged[key](value)

  has: (setting) ->

    @keyForSetting.has(setting.value)

  setValue: (setting, value) ->

    row = @settings.get(@keyForSetting.get(setting.value))

    row.jsValue = value

    row.onChangeFunc(value) if row.onChangeFunc?

  registerWidget: (device, deviceAttr, graphValueChanged) ->

    key = device.value + " " + deviceAttr.value

    @onChanged[key] = graphValueChanged

    if @settings.has(key)

      row = @settings.get(key)

      row.onChangeFunc = graphValueChanged

      row.onChangeFunc(row.jsValue)

  effectSettingLookup: (device, attr) ->

    key = device.value + " " + attr.value

    if @settings.has(key)

      return @settings.get(key).setting

    return null

  deleteSetting: (setting) ->

    log('deleteSetting ' + setting.value)

    key = @keyForSetting.get(setting.value)

    row = @settings.get(key)

    if row? and not row.setting.equals(setting)

      throw new Error('corrupt row for ' + setting.value)

    row.onChangeFunc(null) if row?.onChangeFunc?

    @settings.delete(key)

    @keyForSetting.delete(setting)

  clear: ->

    new Map(@settings).forEach (row, key) ->

    @settings.clear()

    @keyForSetting.clear()

  forAll: (cb) ->

    all = Array.from(@keyForSetting.keys())

    for s in all

      cb(@graph.Uri(s))

  allSettingsStr: ->

    @keyForSetting.keys()

class GraphToControls

  # More efficient bridge between liveControl widgets and graph edits,

  # as opposed to letting each widget scan the graph and push lots of

  # tiny patches to it.

  constructor: (@graph) ->

    @activeSettings = new ActiveSettings(@graph)

    @effect = null

  ctxForEffect: (effect) ->

    @graph.Uri(effect.value.replace(

      "light9.bigasterisk.com/effect",

      "light9.bigasterisk.com/show/dance2018/effect"))

  setEffect: (effect) ->

    @clearSettings()

    @effect = effect

    @ctx = @ctxForEffect(@effect)

    # are these going to pile up? consider @graph.triggerHandler('GTC sync')

    @graph.runHandler(@syncFromGraph.bind(@), 'GraphToControls sync')

  newEffect: ->

    # wrong- this should be our editor's scratch effect, promoted to a

    # real one when you name it.

    U = (x) => @graph.Uri(x)

    effect = @graph.nextNumberedResource(U('http://light9.bigasterisk.com/effect/effect'))

    ctx = @ctxForEffect(effect)

    quad = (s, p, o) => @graph.Quad(s, p, o, ctx)

    addQuads = [

      quad(effect, U('rdf:type'), U(':Effect'))

      quad(effect, U('rdfs:label'), @graph.Literal(effect.value.replace(/.*\//, "")))

      quad(effect, U(':publishAttr'), U(':strength'))

    ]

    patch = {addQuads: addQuads, delQuads: []}

    log('init new effect', patch)

    @graph.applyAndSendPatch(patch)

    return effect