import { Injectable, Logger } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { CampaignType } from '../campaigns/enums/campaign-type.enum';
import { getCampaignTypeDefinition } from '../campaigns/constants/campaign-types.constants';
import { Reserve } from '../reserves/entities/reserve.entity';
import { Salon } from '../salons/entities/salon.entity';
import { buildReserveSmsVariables } from '../sms-settings/utils/build-reserve-sms-variables.util';
import { NotificationScenarioKey } from './enums/notification-scenario-key.enum';
import { NotificationDispatchService } from './notification-dispatch.service';

@Injectable()
export class SalonNotificationsService {
  private readonly logger = new Logger(SalonNotificationsService.name);

  constructor(
    private readonly notificationDispatchService: NotificationDispatchService,
    @InjectRepository(Salon)
    private readonly salonsRepository: Repository<Salon>,
    @InjectRepository(Reserve)
    private readonly reservesRepository: Repository<Reserve>,
  ) {}

  async notifyReserveCreated(reserveId: string): Promise<void> {
    await this.notifyForReserve(
      reserveId,
      NotificationScenarioKey.RESERVE_CREATED,
      `/work-schedule`,
    );
  }

  async notifyReserveConfirmed(reserveId: string): Promise<void> {
    await this.notifyForReserve(
      reserveId,
      NotificationScenarioKey.RESERVE_CONFIRMED,
      `/work-schedule`,
    );
  }

  async notifyReserveCancelled(reserveId: string): Promise<void> {
    await this.notifyForReserve(
      reserveId,
      NotificationScenarioKey.RESERVE_CANCELLED,
      `/work-schedule`,
    );
  }

  async notifyReserveRemindersSent(params: {
    salonId: string;
    sentCount: number;
    appointmentDate: string;
  }): Promise<void> {
    if (params.sentCount <= 0) {
      return;
    }

    const salon = await this.salonsRepository.findOne({
      where: { id: params.salonId },
    });
    if (!salon) {
      return;
    }

    const appointmentDate = this.formatDate(params.appointmentDate);

    await this.safeCreate({
      salonId: salon.id,
      userId: salon.ownerId,
      key: NotificationScenarioKey.RESERVE_REMINDER_SENT,
      variables: {
        salonName: salon.name,
        sentCount: params.sentCount.toLocaleString('fa-IR'),
        appointmentDate,
      },
      link: '/work-schedule',
      relatedEntityType: 'reserve_reminder',
      relatedEntityId: null,
    });
  }

  async notifyCampaignSent(params: {
    salon: Salon;
    type: CampaignType;
    campaignRunId: string;
    sentCount: number;
    failedCount: number;
    targetCount: number;
    estimatedRevenue: number;
  }): Promise<void> {
    const definition = getCampaignTypeDefinition(params.type);
    const key =
      params.sentCount === 0
        ? NotificationScenarioKey.CAMPAIGN_FAILED
        : NotificationScenarioKey.CAMPAIGN_SENT;

    await this.safeCreate({
      salonId: params.salon.id,
      userId: params.salon.ownerId,
      key,
      variables: {
        salonName: params.salon.name,
        campaignLabel: definition.label,
        campaignType: params.type,
        sentCount: params.sentCount.toLocaleString('fa-IR'),
        failedCount: params.failedCount.toLocaleString('fa-IR'),
        targetCount: params.targetCount.toLocaleString('fa-IR'),
        estimatedRevenue: params.estimatedRevenue.toLocaleString('fa-IR'),
      },
      link: `/campaigns/results/${params.campaignRunId}`,
      relatedEntityType: 'campaign_run',
      relatedEntityId: params.campaignRunId,
    });
  }

  async notifyCampaignFailed(params: {
    salon: Salon;
    type: CampaignType;
    targetCount: number;
  }): Promise<void> {
    const definition = getCampaignTypeDefinition(params.type);

    await this.safeCreate({
      salonId: params.salon.id,
      userId: params.salon.ownerId,
      key: NotificationScenarioKey.CAMPAIGN_FAILED,
      variables: {
        salonName: params.salon.name,
        campaignLabel: definition.label,
        campaignType: params.type,
        targetCount: params.targetCount.toLocaleString('fa-IR'),
      },
      link: '/campaigns',
      relatedEntityType: 'campaign',
      relatedEntityId: null,
    });
  }

  private async notifyForReserve(
    reserveId: string,
    key: NotificationScenarioKey,
    link: string,
  ): Promise<void> {
    const reserve = await this.reservesRepository.findOne({
      where: { id: reserveId },
      relations: {
        salon: true,
        customer: { user: true },
        stylist: { user: true },
      },
    });

    if (!reserve?.salon) {
      return;
    }

    const variables = buildReserveSmsVariables(reserve);

    await this.safeCreate({
      salonId: reserve.salonId,
      userId: reserve.salon.ownerId,
      key,
      variables,
      link,
      relatedEntityType: 'reserve',
      relatedEntityId: reserve.id,
    });
  }

  private async safeCreate(params: {
    salonId: string;
    userId: string;
    key: NotificationScenarioKey;
    variables: Record<string, string>;
    link?: string | null;
    relatedEntityType?: string | null;
    relatedEntityId?: string | null;
  }): Promise<void> {
    try {
      await this.notificationDispatchService.createForSalon(params);
    } catch (error) {
      this.logger.error(
        `Failed to create notification ${params.key} for salon ${params.salonId}`,
        error instanceof Error ? error.stack : undefined,
      );
    }
  }

  private formatDate(date: string): string {
    const parsed = new Date(`${date}T00:00:00`);
    if (Number.isNaN(parsed.getTime())) {
      return date;
    }
    return parsed.toLocaleDateString('fa-IR');
  }
}