import {Injectable, Inject} from "@angular/core";
import {VisitedRoute} from "./structures/visited-route";
import {Subject} from "rxjs";
import {Router, NavigationStart, NavigationEnd} from "@angular/router";
import {UserClick} from "./structures/click";

/**
 * Session flow service. Track information about user activity, such as:
 * 1. Session id
 * 2. Device id
 * 3. User id
 * 3. Is mobile user
 * 4. Refferer url
 * 5. Saves visited routes
 * 6. Saves user clicks
 * 
 * To enable `Session Flow` for tracking inject `DAL` and `Session Flow` into root `AppComponent`. If you want to track user click also add HostListener on click:
 * ```
 * export class AppComponent {
 *
 * \@HostListener('click', ['$event']) onClick(e){
 *    this.sessionFlow.addUserClick(e);
 * }
 *
 * 
 * constructor(
 *            private dal: DbAbstractionLayer,
 *            private sessionFlow: SessionFlow
 *            ) {
 * }
 *
 * ngOnInit() {
 *    this.dal.checkOldSessionFlow(this.sessionFlow.deviceId);
 *    this.dal.connectSessionFlowToDB(this.sessionFlow, this.sessionFlow.deviceId, this.sessionFlow.sessionId);
 * }
 * ```
 * 
 */
@Injectable()
export class SessionFlow{

  /**
   * Current session id
   */
  sessionId: string;

  /**
   * Current device id
   */
  deviceId: string;

  /**
   * Is mobile user
   */
  isMobile: boolean;
  
  /**
   * Refferer url
   */
  reffererUrl: string = '';

  /**
   * RxJs subject for visited routes
   */
  visitedRoute: Subject<VisitedRoute> = new Subject<VisitedRoute>();

  /**
   * RxJs subject for user clicks
   */
  click: Subject<UserClick> = new Subject<UserClick>();

  /**
   * Current user id
   */
  userId: string;

  /**
   * Last route. For default "/"
   */
  private lastRoute: string = '/';

  /**
   * Start time of enter for last route
   */
  private lastRouteTimeStart: Date = new Date();

  constructor(protected router: Router, @Inject('isBrowser') protected isBrowser){
    this.userId = 'guest';
    if(isBrowser){
      this.reffererUrl = document.referrer;
    }
    this.createDeviceId();
    this.createSessionId();
    this.trackRouteChange();
  }

  /**
   * Create new visited route
   */
  createVisitedRoute(){
    let visitedRoute: VisitedRoute = new VisitedRoute();
    visitedRoute.route = this.lastRoute;
    visitedRoute.timeStart = this.lastRouteTimeStart;
    visitedRoute.timeEnd = new Date();
    visitedRoute.calcDuration();
    this.visitedRoute.next(visitedRoute);
  }

  /**
   * Tracks router changes 
   */
  private trackRouteChange(){
    this.router.events
      .subscribe((event) => {

        //User started to load the page
        if (event instanceof NavigationStart) {
          event = event as NavigationStart;
          this.createVisitedRoute();
        }
        //User ended to load the page
        if (event instanceof NavigationEnd){
          event = event as NavigationEnd;
          this.lastRoute = event.url;
          this.lastRouteTimeStart = new Date();
        }
      });
  }

  /**
   * Create session id 
   */
  private createSessionId() {
    this.sessionId = this.guid();
    this.isMobile = this.detectMobileDevice();
    this.setCookie('mobile', this.detectMobileDevice() + "", 0);
    this.setCookie('session_id', this.sessionId, 0);
  }

  /**
   * Create guid for session id and device id
   */
  private guid() {
    function s4() {
      return Math.floor((1 + Math.random()) * 0x10000)
        .toString(16)
        .substring(1);
    }
    return s4() + s4() + '-' + s4() + '-' + s4() + '-' +
      s4() + '-' + s4() + s4() + s4();
  }

  /**
   * Return true if user use mobile device
   */
  private detectMobileDevice(){
    var check = false;
    if(this.isBrowser){
      ((a) => {if(/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|mobile.+firefox|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows ce|xda|xiino|android|ipad|playbook|silk/i.test(a)||/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test(a.substr(0,4))) check = true;})(navigator.userAgent||navigator.vendor);
    }
    return check;
  }

  /**
   * Set cookie
   * @param {string} cname cookie name
   * @param {string} cvalue cookie value
   * @param {integer} exdays expires days 
   */
  private setCookie(cname, cvalue, exdays) {
    if(this.isBrowser){
      let d = new Date();
      d.setTime(d.getTime() + (exdays*24*60*60*1000));
      let expires = "expires="+ d.toUTCString();
      document.cookie = cname + "=" + cvalue + "; ";
    }
  }

  /**
   * Get cookie
   * @param {string} cname  cookie name
   */
  private getCookie(cname) {
    if(this.isBrowser){
      var name = cname + "=";
      var ca = document.cookie.split(';');
      for(var i = 0; i <ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') {
          c = c.substring(1);
        }
        if (c.indexOf(name) == 0) {
          return c.substring(name.length,c.length);
        }
      }
    }
    return "";
  }

  /**
   * Create device id
   */
  private createDeviceId() {
    if(this.getCookie("device_id") === ""){
      this.deviceId = this.guid();
      this.setCookie("device_id", this.deviceId, 100);
    }
    else{
      this.deviceId = this.getCookie("device_id");
    }
  }

  /**
   * Add new user click
   * @param e browser click event
   */
  addUserClick(e) {
    let userClick = new UserClick();
    let targetValues = ['id', 'name', 'className', 'innerText'];
    userClick.selectorName = "undefined";
    for(let i = 0; i < targetValues.length; i++){
      let targetVal = targetValues[i];
      if(e.target[targetVal]){
        if(typeof e.target[targetVal] === 'object'){
          userClick.selectorName = e.target[targetVal].name;
        }else{
          userClick.selectorName = e.target[targetVal];
        }
        break;
      }
    }
    userClick.time = new Date();
    userClick.route = this.router.url;
    this.click.next(userClick);
  }



}