import { Component, ApplicationRef, OnInit, OnDestroy, HostListener, ViewChild, ComponentRef } from "@angular/core";
import { Router, Event, NavigationEnd, ActivationEnd } from "@angular/router";
import { MatSidenav, MatToolbar, MatDialog, MatIconRegistry } from "@angular/material";
import { DomSanitizer } from "@angular/platform-browser";

import { Observer, jalhydDateRev, jalhydVersion, CalculatorType, Session } from "jalhyd";

import { environment } from "../environments/environment";
import { I18nService } from "./services/internationalisation/internationalisation.service";
import { ErrorService } from "./services/error/error.service";
import { FormulaireService } from "./services/formulaire/formulaire.service";
import { FormulaireDefinition } from "./formulaire/definition/form-definition";
import { ServiceFactory } from "./services/service-factory";
import { HttpService } from "./services/http/http.service";
import { ApplicationSetupService } from "./services/app-setup/app-setup.service";
import { nghydDateRev, nghydVersion } from "../date_revision";

import { DialogConfirmEmptySessionComponent } from "./components/dialog-confirm-empty-session/dialog-confirm-empty-session.component";
import { DialogLoadSessionComponent } from "./components/dialog-load-session/dialog-load-session.component";
import { DialogSaveSessionComponent } from "./components/dialog-save-session/dialog-save-session.component";
import { NotificationsService } from "./services/notifications/notifications.service";


@Component({
  selector: "nghyd-app",
  templateUrl: "./app.component.html",
  styleUrls: ["./app.component.scss"],
  providers: [ErrorService]
})
export class AppComponent implements OnInit, OnDestroy, Observer {

  @ViewChild("sidenav")
  public sidenav: MatSidenav;

  @ViewChild("navbar")
  public navbar: MatToolbar;

  /** current calculator, inferred from _currentFormId by setActiveCalc() (used for navbar menu) */
  public currentCalc: any;

  /**
   * liste des modules de calcul. Forme des objets :
   * "title": nom du module de calcul
   * "uid": id unique du formulaire
   */
  private _calculators: any[] = [];

  /**
   * id du formulaire courant
   * on utilise pas directement FormulaireService.currentFormId pour éviter l'erreur
   * ExpressionChangedAfterItHasBeenCheckedError
   */
  private _currentFormId: string;

  private _innerWidth: number;

  /**
   * composant actuellement affiché par l'élément <router-outlet>
   */
  private _routerCurrentComponent: Component;

  constructor(
    private intlService: I18nService,
    private appSetupService: ApplicationSetupService,
    private appRef: ApplicationRef,
    private errorService: ErrorService,
    private router: Router,
    private formulaireService: FormulaireService,
    private httpService: HttpService,
    private notificationsService: NotificationsService,
    private confirmEmptySessionDialog: MatDialog,
    private saveSessionDialog: MatDialog,
    private loadSessionDialog: MatDialog,
    private matIconRegistry: MatIconRegistry,
    private domSanitizer: DomSanitizer
  ) {
    ServiceFactory.instance.httpService = httpService;
    ServiceFactory.instance.applicationSetupService = appSetupService;
    ServiceFactory.instance.i18nService = intlService;
    ServiceFactory.instance.formulaireService = formulaireService;
    ServiceFactory.instance.notificationsService = notificationsService;

    this.router.events.subscribe((event: Event) => {
      // close side navigation when clicking a calculator tab
      if (event instanceof NavigationEnd) {
        this.sidenav.close();
        window.scrollTo(0, 0);
      }
      // [de]activate calc tabs depending on loaded route
      if (event instanceof ActivationEnd) {
        const path = event.snapshot.url[0].path;
        if (path === "calculator") {
          const calcUid = event.snapshot.params.uid;
          if (this.calculatorExists(calcUid)) {
            this.setActiveCalc(calcUid);
          } else {
            // if required calculator does not exist, redirect to list page
            this.toList();
          }
        } else {
          this.setActiveCalc(null);
        }
      }
    });

    // icônes personnalisées
    this.matIconRegistry.addSvgIcon(
      "file_excel",
      this.domSanitizer.bypassSecurityTrustResourceUrl("../../assets/icons/file-excel.svg")
    );
  }

  /**
   * Triggered at app startup.
   * Preferences are loaded by app setup service
   * @see ApplicationSetupService.construct()
   */
  ngOnInit() {
    this.formulaireService.addObserver(this);
    this.subscribeErrorService();
    this._innerWidth = window.innerWidth;
  }

  ngOnDestroy() {
    this.unsubscribeErrorService();
    this.formulaireService.removeObserver(this);
  }

  @HostListener("window:resize", ["$event"])
  onResize(event) {
    // keep track of window size for navbar tabs arrangement
    this._innerWidth = window.innerWidth;
  }

  public get uitextSidenavNewCalc() {
    return this.intlService.localizeText("INFO_MENU_NOUVELLE_CALC");
  }

  public get uitextSidenavParams() {
    return this.intlService.localizeText("INFO_SETUP_TITLE");
  }

  public get uitextSidenavLoadSession() {
    return this.intlService.localizeText("INFO_MENU_LOAD_SESSION_TITLE");
  }

  public get uitextSidenavSaveSession() {
    return this.intlService.localizeText("INFO_MENU_SAVE_SESSION_TITLE");
  }

  public get uitextSidenavEmptySession() {
    return this.intlService.localizeText("INFO_MENU_EMPTY_SESSION_TITLE");
  }

  public get uitextSidenavReportBug() {
    return this.intlService.localizeText("INFO_MENU_REPORT_BUG");
  }

  public get uitextSidenavHelp() {
    return this.intlService.localizeText("INFO_MENU_HELP_TITLE");
  }

  public get uitextSelectCalc() {
    return this.intlService.localizeText("INFO_MENU_SELECT_CALC");
  }

  public getCalculatorLabel(t: CalculatorType) {
    return this.formulaireService.getLocalisedTitleFromCalculatorType(t);
  }

  public get calculators() {
    return this._calculators;
  }

  public get currentFormId() {
    return this._currentFormId;
  }

  public get currentRoute(): string {
    return this.router.url;
  }

  public setActiveCalc(uid: string) {
    this._calculators.forEach((calc) => {
      calc.active = (calc.uid === uid);
    });
    // mark current calc for navbar menu
    const index = this.getCalculatorIndexFromId(uid);
    this.currentCalc = this._calculators[index];
  }

  /**
   * Returns true if sum of open calculator tabs witdh is lower than navbar
   * available space (ie. if navbar is not overflowing), false otherwise
   */
  public get tabsFitInNavbar() {
    // manual breakpoints
    // @WARNING keep in sync with .calculator-buttons sizes in app.component.scss
    let tabsLimit = 0;
    if (this._innerWidth > 480) {
      tabsLimit = 3;
    }
    if (this._innerWidth > 640) {
      tabsLimit = 4;
    }
    if (this._innerWidth > 800) {
      tabsLimit = 6;
    }
    /*if (this._innerWidth > 1200) {
      tabsLimit = 8;
    }*/

    const fits = this._calculators.length <= tabsLimit;
    return fits;
  }

  /**
   * abonnement au service d'erreurs
   */
  private subscribeErrorService() {
    this.errorService.addObserver(this);
  }

  private unsubscribeErrorService() {
    this.errorService.removeObserver(this);
  }

  // interface Observer

  update(sender: any, data: any): void {
    if (sender instanceof FormulaireService) {
      switch (data["action"]) {
        case "createForm":
        // add newly created form to calculators list
          const f: FormulaireDefinition = data["form"];
          this._calculators.push(
            {
              "title": f.calculatorName,
              "type": f.calculatorType,
              "uid": f.uid
            }
          );

          // abonnement en tant qu'observateur du nouveau formulaire
          f.addObserver(this);
          break;

        case "invalidFormId":
          this.toList();
          break;

        case "currentFormChanged":
          this._currentFormId = data["formId"];
          break;

        case "saveForm":
          this.saveForm(data["form"]);
          break;

        case "closeForm":
          const form: FormulaireDefinition = data["form"];
          this.closeCalculator(form);
          break;
      }
    } else if (sender instanceof FormulaireDefinition) {
      switch (data["action"]) {
        case "nameChanged":
          this.updateCalculatorTitle(sender, data["name"]);
          break;
      }
    }
  }

  /**
   * Returns true if a form having "formUid" as UID exists
   * @param formId UID to look for
   */
  private calculatorExists(formId: string): boolean {
    return (this.getCalculatorIndexFromId(formId) > -1);
  }

  private getCalculatorIndexFromId(formId: string) {
    const index = this._calculators.reduce((resultIndex, calc, currIndex) => {
      if (resultIndex === -1 && calc["uid"] === formId) {
        resultIndex = currIndex;
      }
      return resultIndex;
    }, -1);

    return index;
  }

  private updateCalculatorTitle(f: FormulaireDefinition, title: string) {
    const formIndex = this.getCalculatorIndexFromId(f.uid);
    this._calculators[formIndex]["title"] = title;
  }

  /**
   * Saves a JSON serialised session file, for one or more calc modules
   * @param calcList modules to save
   * @param filename
   */
  private saveSession(calcList: any[], filename) {
    const elems = [];
    const serialiseOptions: { [key: string]: {} } = {};
    for (const c of calcList) {
      if (c.selected) {
        serialiseOptions[c.uid] = { // GUI-dependent metadata to add to the session file
          title: c.title
        };
      }
    }
    const session: string = Session.getInstance().serialise(serialiseOptions);
    this.formulaireService.downloadTextFile(session, filename);
  }

  /**
   * Supprime un module de calcul **de l'interface**
   * ATTENTION, ne supprime pas le module de calcul en mémoire !
   * Pour cela, utiliser FormulaireService.requestCloseForm(form.uid);
   * @param form module de calcul à fermer
   */
  private closeCalculator(form: FormulaireDefinition) {
    const formId: string = form.uid;

    // désabonnement en tant qu'observateur
    form.removeObserver(this);
    // recherche du module de calcul correspondant à formId
    const closedIndex = this.getCalculatorIndexFromId(formId);

    /*
     * détermination du nouveau module de calcul à afficher :
     * - celui après celui supprimé
     * - ou celui avant celui supprimé si on supprime le dernier
     */
    let newId = null;
    const l = this._calculators.length;
    if (l > 1) {
      if (closedIndex === l - 1) {
        newId = this._calculators[closedIndex - 1]["uid"];
      } else {
        newId = this._calculators[closedIndex + 1]["uid"];
      }
    }

    // suppression

    this._calculators = this._calculators.filter(calc => {
      return formId !== calc["uid"];
    });

    // MAJ affichage

    if (newId === null) {
      this.toList();
      this._currentFormId = null;
    } else {
      this.toCalc(newId);
    }
  }

  private toList() {
    this.router.navigate(["/list"]);
  }

  private toCalc(id: string) {
    this.router.navigate(["/calculator", id]);
    this.setActiveCalc(id);
  }

  /**
   * récupération du composant affiché par le routeur
   */
  public onRouterOutletActivated(a) {
    this._routerCurrentComponent = a;
  }

  /**
   * restarts a fresh session by closing all calculators
   */
  public emptySession() {
    const dialogRef = this.confirmEmptySessionDialog.open(
      DialogConfirmEmptySessionComponent,
      { disableClose: true }
    );
    dialogRef.afterClosed().subscribe(result => {
      if (result) {
        this.doEmptySession();
      }
    });
  }

  public doEmptySession() {
    for (const c of this._calculators) {
      const form = this.formulaireService.getFormulaireFromId(c.uid);
      this.formulaireService.requestCloseForm(form.uid);
    }
    // just to be sure, get rid of any Nub possibly stuck in session without any form attached
    Session.getInstance().clear();
  }

  public loadSession() {
    // création du dialogue de sélection des formulaires à sauver
    const dialogRef = this.loadSessionDialog.open(
      DialogLoadSessionComponent,
      { disableClose: true }
    );
    dialogRef.afterClosed().subscribe(result => {
      if (result) {
        if (result.emptySession) {
          this.doEmptySession();
        }
        this.formulaireService.loadSession(result.file, result.calculators);
      }
    });
  }

  /**
   * Demande au client d'envoyer un email (génère un lien mailto:), pré-rempli
   * avec un texte standard, et le contenu de la session au format JSON
   */
  public reportBug() {
    const recipient = "cassiopee@g-eau.fr";
    const subject = "[ISSUE] " + this.intlService.localizeText("INFO_REPORT_BUG_SUBJECT");
    let body = this.intlService.localizeText("INFO_REPORT_BUG_BODY");
    // add session description
    body += Session.getInstance().serialise();
    body = encodeURIComponent(body);

    const mailtoURL = `mailto:${recipient}?subject=${subject}&body=${body}`;

    // temporarily disable tab closing alert, as tab won't be closed for real
    this.appSetupService.warnBeforeTabClose = false;
    window.location.href = mailtoURL;
    this.appSetupService.warnBeforeTabClose = true;
  }

  public get revisionInfo(): any {
    return {
      jalhyd: {
        date: jalhydDateRev,
        version: jalhydVersion,
      },
      nghyd: {
        date: nghydDateRev,
        version: nghydVersion
      }
    };
  }

  /**
   * sauvegarde du/des formulaires
   * @param form formulaire à sélectionner par défaut dans la liste
   */
  public saveForm(form?: FormulaireDefinition) {
    // liste des formulaires
    const list = [];
    for (const c of this._calculators) {
      const uid = c["uid"];
      list.push({
        "selected": form ? (uid === form.uid) : true,
        "title": c["title"],
        "uid": uid
      });
    }
    // dialogue de sélection des formulaires à sauver
    const dialogRef = this.saveSessionDialog.open(
      DialogSaveSessionComponent,
      {
        data: {
          calculators: list
        },
        disableClose: true
      }
    );
    dialogRef.afterClosed().subscribe(result => {
      if (result) {
        let name = result.filename;

        // ajout extension ".json"
        const re = /.+\.json/;
        const match = re.exec(name.toLowerCase());
        if (match === null) {
          name = name + ".json";
        }

        this.saveSession(result.calculators, name);
      }
    });
  }

  /**
   * détection de la fermeture de la page/navigateur et demande de confirmation
   */
  @HostListener("window:beforeunload", ["$event"])
  confirmExit($event) {
    if (
      this.appSetupService.warnBeforeTabClose
      && environment.production // otherwise prevents dev server to reload app after recompiling
    ) {
      // affecter une valeur différente de null provoque l'affichage d'un dialogue de confirmation, mais le texte n'est pas affiché
      $event.returnValue = "Your data will be lost !";
    }
  }
}