var NavView = View.extend({

  el: "body",
  events: {
    "click #prev": "prev",
    "click #next": "next",
    "click #refresh": "refresh",
    "click #random": "random",
  },
  
  initialize: function(){
    this.id = -1
    this.$pip = this.$("#pip img")
    this.$image = this.$("#luckyimage")
    
    $(window).on("keydown", this.keydown.bind(this))
    $(document).ajaxError(function(){
      this.fetching = false
    }.bind(this))
    
    window.onpopstate = function(event) {
      this.display(event.state)
    }.bind(this)

    if (window.location.pathname.indexOf("/p/") !== -1) {
      var id = window.location.pathname.split("/")[2]
      this.fetch(id)
    }
    else {
      this.latest()
    }
  },
  
  keydown: function(e){
    if (e.shiftKey || e.metaKey || e.ctrlKey || e.altKey) { return }
    switch (e.keyCode) {
      case 37: // left
        this.prev()
        break
      case 39: // right
        this.next()
        break
      case 38: // up
        this.random()
        break
      case 40: // down
        this.latest()
        break
    }
  },
  
  latest: function(){
    if (this.fetching) return
    this.fetch("latest")
    this.onLatest = true
  },
  
  prev: function(){
    if (this.fetching) return
    if (this.id - 1 < 1) { return }
    this.fetch(this.id-1)
  },
  
  next: function(){
    if (this.fetching) return
    if (this.onLatest || this.id < 1) { return }
    this.fetch(this.id+1)
  },
  
  random: function(){
    if (this.fetching) return
    this.fetch("random")
  },
  
  fetch: function(id){
    this.fetching = true
    this.onLatest = false
    $.get("/get/" + id, function(data){
      this.fetching = false
      this.display(data)
      history.pushState(data, document.title, "/p/" + data.id)
    }.bind(this))
  },
  
  display: function(data){
    if (! data || ! data.id) {
      this.onLatest = true
      return
    }
    this.id = data.id
    this.$pip.attr("src", data.url)
    this.$image.css("background-image", "url(" + data.url + ")")
  },

})