import { Directive } from "@angular/core";

import { ExportService } from "@bitwarden/common/abstractions/export.service";
import { FileDownloadService } from "@bitwarden/common/abstractions/fileDownload/fileDownload.service";
import { I18nService } from "@bitwarden/common/abstractions/i18n.service";
import { LogService } from "@bitwarden/common/abstractions/log.service";
import { PlatformUtilsService } from "@bitwarden/common/abstractions/platformUtils.service";
import { EventResponse } from "@bitwarden/common/models/response/eventResponse";
import { ListResponse } from "@bitwarden/common/models/response/listResponse";
import { EventView } from "@bitwarden/common/models/view/eventView";

import { EventService } from "src/app/services/event.service";

@Directive()
export abstract class BaseEventsComponent {
  loading = true;
  loaded = false;
  events: EventView[];
  start: string;
  end: string;
  dirtyDates = true;
  continuationToken: string;
  refreshPromise: Promise<any>;
  exportPromise: Promise<any>;
  morePromise: Promise<any>;

  abstract readonly exportFileName: string;

  constructor(
    protected eventService: EventService,
    protected i18nService: I18nService,
    protected exportService: ExportService,
    protected platformUtilsService: PlatformUtilsService,
    protected logService: LogService,
    protected fileDownloadService: FileDownloadService
  ) {
    const defaultDates = this.eventService.getDefaultDateFilters();
    this.start = defaultDates[0];
    this.end = defaultDates[1];
  }

  async exportEvents() {
    if (this.appApiPromiseUnfulfilled() || this.dirtyDates) {
      return;
    }

    this.loading = true;

    const dates = this.parseDates();
    if (dates == null) {
      return;
    }

    try {
      this.exportPromise = this.export(dates[0], dates[1]);

      await this.exportPromise;
    } catch (e) {
      this.logService.error(`Handled exception: ${e}`);
    }

    this.exportPromise = null;
    this.loading = false;
  }

  async loadEvents(clearExisting: boolean) {
    if (this.appApiPromiseUnfulfilled()) {
      return;
    }

    const dates = this.parseDates();
    if (dates == null) {
      return;
    }

    this.loading = true;
    let events: EventView[] = [];
    try {
      const promise = this.loadAndParseEvents(
        dates[0],
        dates[1],
        clearExisting ? null : this.continuationToken
      );
      if (clearExisting) {
        this.refreshPromise = promise;
      } else {
        this.morePromise = promise;
      }
      const result = await promise;
      this.continuationToken = result.continuationToken;
      events = result.events;
    } catch (e) {
      this.logService.error(`Handled exception: ${e}`);
    }

    if (!clearExisting && this.events != null && this.events.length > 0) {
      this.events = this.events.concat(events);
    } else {
      this.events = events;
    }

    this.dirtyDates = false;
    this.loading = false;
    this.morePromise = null;
    this.refreshPromise = null;
  }

  protected abstract requestEvents(
    startDate: string,
    endDate: string,
    continuationToken: string
  ): Promise<ListResponse<EventResponse>>;
  protected abstract getUserName(r: EventResponse, userId: string): { name: string; email: string };

  protected async loadAndParseEvents(
    startDate: string,
    endDate: string,
    continuationToken: string
  ) {
    const response = await this.requestEvents(startDate, endDate, continuationToken);

    const events = await Promise.all(
      response.data.map(async (r) => {
        const userId = r.actingUserId == null ? r.userId : r.actingUserId;
        const eventInfo = await this.eventService.getEventInfo(r);
        const user = this.getUserName(r, userId);
        const userName = user != null ? user.name : this.i18nService.t("unknown");

        return new EventView({
          message: eventInfo.message,
          humanReadableMessage: eventInfo.humanReadableMessage,
          appIcon: eventInfo.appIcon,
          appName: eventInfo.appName,
          userId: userId,
          userName: r.installationId != null ? `Installation: ${r.installationId}` : userName,
          userEmail: user != null ? user.email : "",
          date: r.date,
          ip: r.ipAddress,
          type: r.type,
          installationId: r.installationId,
        });
      })
    );
    return { continuationToken: response.continuationToken, events: events };
  }

  protected parseDates() {
    let dates: string[] = null;
    try {
      dates = this.eventService.formatDateFilters(this.start, this.end);
    } catch (e) {
      this.platformUtilsService.showToast(
        "error",
        this.i18nService.t("errorOccurred"),
        this.i18nService.t("invalidDateRange")
      );
      return null;
    }
    return dates;
  }

  protected appApiPromiseUnfulfilled() {
    return this.refreshPromise != null || this.morePromise != null || this.exportPromise != null;
  }

  private async export(start: string, end: string) {
    let continuationToken = this.continuationToken;
    let events = [].concat(this.events);

    while (continuationToken != null) {
      const result = await this.loadAndParseEvents(start, end, continuationToken);
      continuationToken = result.continuationToken;
      events = events.concat(result.events);
    }

    const data = await this.exportService.getEventExport(events);
    const fileName = this.exportService.getFileName(this.exportFileName, "csv");
    this.fileDownloadService.download({
      fileName,
      blobData: data,
      blobOptions: { type: "text/plain" },
    });
  }
}