require("../polyfills/Function.prototype.bind")

var on = require("../events/on")
var clone = require("../clone")

var attrClick = "data-pjax-click-state"
var attrKey = "data-pjax-keyup-state"

var linkAction = function(el, event) {
  // Don’t break browser special behavior on links (like page in new window)
  if (event.which > 1 || event.metaKey || event.ctrlKey || event.shiftKey || event.altKey) {
    el.setAttribute(attrClick, "modifier")
    return
  }

  // we do test on href now to prevent unexpected behavior if for some reason
  // user have href that can be dynamically updated

  // Ignore external links.
  if (el.protocol !== window.location.protocol || el.host !== window.location.host) {
    el.setAttribute(attrClick, "external")
    return
  }

  // Ignore click if we are on an anchor on the same page
  if (el.pathname === window.location.pathname && el.hash.length > 0) {
    el.setAttribute(attrClick, "anchor-present")
    return
  }

  // Ignore anchors on the same page (keep native behavior)
  if (el.hash && el.href.replace(el.hash, "") === window.location.href.replace(location.hash, "")) {
    el.setAttribute(attrClick, "anchor")
    return
  }

  // Ignore empty anchor "foo.html#"
  if (el.href === window.location.href.split("#")[0] + "#") {
    el.setAttribute(attrClick, "anchor-empty")
    return
  }

  event.preventDefault()

  // don’t do "nothing" if user try to reload the page by clicking the same link twice
  if (
    this.options.currentUrlFullReload &&
    el.href === window.location.href.split("#")[0]
  ) {
    el.setAttribute(attrClick, "reload")
    this.reload()
    return
  }
  this.options.requestOptions = this.options.requestOptions || {};
  el.setAttribute(attrClick, "load")
  this.loadUrl(el.href, clone(this.options))
}

var isDefaultPrevented = function(event) {
  return event.defaultPrevented || event.returnValue === false;
}

module.exports = function(el) {
  var that = this

  on(el, "click", function(event) {
    if (isDefaultPrevented(event)) {
      return
    }

    linkAction.call(that, el, event)
  })

  on(el, "keyup", function(event) {
    if (isDefaultPrevented(event)) {
      return
    }

    // Don’t break browser special behavior on links (like page in new window)
    if (event.which > 1 || event.metaKey || event.ctrlKey || event.shiftKey || event.altKey) {
      el.setAttribute(attrKey, "modifier")
      return
    }

    if (event.keyCode == 13) {
      linkAction.call(that, el, event)
    }
  }.bind(this))
}