import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { EUserStatus } from '@tria-plc/api-common/utils/enums/user.enum';
import { Employee } from '@tria-plc/iamapi-common';
import { User } from '@tria-plc/iamapi-common/entities/iam/user/user.entity';
import { Freight } from '@edr/types';
import { Repository, ObjectLiteral } from 'typeorm';

import { Booking } from '../bookings/entities/booking.entity';
import { Cargo } from '../cargoes/entities/cargoes.entity';
import { Container } from '../container-management/entities/container.entity';
import { Customer } from '../customers/entities/customer.entity';
import { PaymentEntity } from '../payment/entities/payment.entity';
import { Train } from '../trains/entities/train.entity';
import { Wagon } from '../wagons/entities/wagon.entity';
import {
  OVERVIEW_CLOSED_STATUSES,
  OVERVIEW_IN_APPROVAL_STATUSES,
  OVERVIEW_NEEDS_ACTION_STATUSES,
  OVERVIEW_URGENT_PRIORITY_THRESHOLD,
} from './overview.constants';

export type OverviewBookingKpisRow = {
  totalActive: number;
  needsAction: number;
  urgent: number;
  inApproval: number;
  submittedToday: number;
};

export type OverviewRecentBookingRow = {
  id: string;
  reference: string;
  customerLabel: string;
  status: string;
  priorityScore: number;
  totalAmount: number | null;
  paymentCurrency: string | null;
  createdAt: Date;
};

@Injectable()
export class OverviewRepository {
  constructor(
    @InjectRepository(Booking)
    private readonly bookingRepository: Repository<Booking>,
    @InjectRepository(PaymentEntity)
    private readonly paymentRepository: Repository<PaymentEntity>,
    @InjectRepository(Customer)
    private readonly customerRepository: Repository<Customer>,
    @InjectRepository(Train)
    private readonly trainRepository: Repository<Train>,
    @InjectRepository(Wagon)
    private readonly wagonRepository: Repository<Wagon>,
    @InjectRepository(Container)
    private readonly containerRepository: Repository<Container>,
    @InjectRepository(Cargo)
    private readonly cargoRepository: Repository<Cargo>,
    @InjectRepository(Employee)
    private readonly employeeRepository: Repository<Employee>,
    @InjectRepository(User)
    private readonly userRepository: Repository<User>,
  ) {}

  async getBookingKpis(): Promise<OverviewBookingKpisRow> {
    const row = await this.bookingRepository
      .createQueryBuilder('booking')
      .select(
        `COUNT(*) FILTER (WHERE booking.status NOT IN (:...closedStatuses) AND booking.status != 'DRAFT')::int`,
        'totalActive',
      )
      .addSelect(
        `COUNT(*) FILTER (WHERE booking.status IN (:...needsActionStatuses))::int`,
        'needsAction',
      )
      .addSelect(
        `COUNT(*) FILTER (WHERE booking.priority_score >= :urgentThreshold)::int`,
        'urgent',
      )
      .addSelect(
        `COUNT(*) FILTER (WHERE booking.status IN (:...inApprovalStatuses))::int`,
        'inApproval',
      )
      .addSelect(
        `COUNT(*) FILTER (WHERE booking.created_at >= CURRENT_DATE AND booking.status != 'DRAFT')::int`,
        'submittedToday',
      )
      .where('booking.deleted_at IS NULL')
      .setParameters({
        closedStatuses: [...OVERVIEW_CLOSED_STATUSES],
        needsActionStatuses: [...OVERVIEW_NEEDS_ACTION_STATUSES],
        inApprovalStatuses: [...OVERVIEW_IN_APPROVAL_STATUSES],
        urgentThreshold: OVERVIEW_URGENT_PRIORITY_THRESHOLD,
      })
      .getRawOne<Record<string, string>>();

    return {
      totalActive: Number(row?.totalActive ?? 0),
      needsAction: Number(row?.needsAction ?? 0),
      urgent: Number(row?.urgent ?? 0),
      inApproval: Number(row?.inApproval ?? 0),
      submittedToday: Number(row?.submittedToday ?? 0),
    };
  }

  async getOperationsKpis(): Promise<{
    trainsActive: number;
    wagonsAvailable: number;
    containersInTransit: number;
    cargoesLoaded: number;
  }> {
    const [trainsActive, wagonsAvailable, containersInTransit, cargoesLoaded] =
      await Promise.all([
        this.trainRepository
          .createQueryBuilder('train')
          .where('train.deleted_at IS NULL')
          .andWhere('train.status IN (:...statuses)', {
            statuses: [
              Freight.TrainStatus.InService,
              Freight.TrainStatus.Scheduled,
            ],
          })
          .getCount(),
        this.wagonRepository
          .createQueryBuilder('wagon')
          .where('wagon.deleted_at IS NULL')
          .andWhere('wagon.status = :status', { status: Freight.WagonStatus.Available })
          .getCount(),
        this.containerRepository
          .createQueryBuilder('container')
          .where('container.deleted_at IS NULL')
          .andWhere('container.status = :status', { status: 'IN_TRANSIT' })
          .getCount(),
        this.cargoRepository
          .createQueryBuilder('cargo')
          .where('cargo.deleted_at IS NULL')
          .andWhere('cargo.status IN (:...statuses)', {
            statuses: ['LOADED', 'IN_TRANSIT'],
          })
          .getCount(),
      ]);

    return { trainsActive, wagonsAvailable, containersInTransit, cargoesLoaded };
  }

  async getCustomerKpis(): Promise<{
    totalCustomers: number;
    newCustomersThisMonth: number;
  }> {
    const row = await this.customerRepository
      .createQueryBuilder('customer')
      .select('COUNT(*)::int', 'totalCustomers')
      .addSelect(
        `COUNT(*) FILTER (WHERE customer.created_at >= date_trunc('month', CURRENT_DATE))::int`,
        'newCustomersThisMonth',
      )
      .where('customer.deleted_at IS NULL')
      .getRawOne<Record<string, string>>();

    return {
      totalCustomers: Number(row?.totalCustomers ?? 0),
      newCustomersThisMonth: Number(row?.newCustomersThisMonth ?? 0),
    };
  }

  async getBillingKpis(): Promise<{
    revenueMtdEtb: number;
    revenueMtdUsd: number;
    pendingPayments: number;
    successfulPaymentsMtd: number;
  }> {
    const revenueRow = await this.paymentRepository
      .createQueryBuilder('payment')
      .select(
        `COALESCE(SUM(payment.amount) FILTER (WHERE payment.currency = 'ETB'), 0)`,
        'revenueMtdEtb',
      )
      .addSelect(
        `COALESCE(SUM(payment.amount) FILTER (WHERE payment.currency = 'USD'), 0)`,
        'revenueMtdUsd',
      )
      .addSelect(`COUNT(*)::int`, 'successfulPaymentsMtd')
      .where('payment.status = :status', { status: 'success' })
      .andWhere(
        `COALESCE(payment.paid_at, payment.created_at) >= date_trunc('month', CURRENT_DATE)`,
      )
      .getRawOne<Record<string, string>>();

    const pendingPayments = await this.paymentRepository
      .createQueryBuilder('payment')
      .where('payment.status IN (:...statuses)', {
        statuses: ['action-required', 'processing'],
      })
      .getCount();

    return {
      revenueMtdEtb: Number(revenueRow?.revenueMtdEtb ?? 0),
      revenueMtdUsd: Number(revenueRow?.revenueMtdUsd ?? 0),
      pendingPayments,
      successfulPaymentsMtd: Number(revenueRow?.successfulPaymentsMtd ?? 0),
    };
  }

  async getStaffKpis(): Promise<{ activeEmployees: number; activeUsers: number }> {
    const [activeEmployees, activeUsers] = await Promise.all([
      this.employeeRepository.count({
        where: { isCurrent: true },
      }),
      this.userRepository.count({
        where: {
          isActive: true,
          status: EUserStatus.ACCEPTED,
        },
      }),
    ]);

    return { activeEmployees, activeUsers };
  }

  async getBookingTrend(days: number): Promise<{ date: string; count: number }[]> {
    const rows = await this.bookingRepository
      .createQueryBuilder('booking')
      .select(`to_char(booking.created_at::date, 'YYYY-MM-DD')`, 'date')
      .addSelect('COUNT(*)::int', 'count')
      .where('booking.deleted_at IS NULL')
      .andWhere(`booking.created_at >= CURRENT_DATE - :days::int + 1`, { days })
      .groupBy('booking.created_at::date')
      .orderBy('booking.created_at::date', 'ASC')
      .getRawMany<{ date: string; count: string }>();

    return rows.map((row) => ({
      date: row.date,
      count: Number(row.count),
    }));
  }

  async getStatusCounts(): Promise<Record<string, number>> {
    const rows = await this.bookingRepository
      .createQueryBuilder('booking')
      .select('booking.status', 'status')
      .addSelect('COUNT(*)::int', 'count')
      .where('booking.deleted_at IS NULL')
      .groupBy('booking.status')
      .getRawMany<{ status: string; count: string }>();

    return Object.fromEntries(
      rows.map((row) => [row.status, Number(row.count)]),
    );
  }

  async getPaymentTrend(
    days: number,
  ): Promise<{ date: string; amountEtb: number; amountUsd: number }[]> {
    const rows = await this.paymentRepository
      .createQueryBuilder('payment')
      .select(
        `to_char(COALESCE(payment.paid_at, payment.created_at)::date, 'YYYY-MM-DD')`,
        'date',
      )
      .addSelect(
        `COALESCE(SUM(payment.amount) FILTER (WHERE payment.currency = 'ETB'), 0)`,
        'amountEtb',
      )
      .addSelect(
        `COALESCE(SUM(payment.amount) FILTER (WHERE payment.currency = 'USD'), 0)`,
        'amountUsd',
      )
      .where('payment.status = :status', { status: 'success' })
      .andWhere(
        `COALESCE(payment.paid_at, payment.created_at) >= CURRENT_DATE - :days::int + 1`,
        { days },
      )
      .groupBy(`COALESCE(payment.paid_at, payment.created_at)::date`)
      .orderBy(`COALESCE(payment.paid_at, payment.created_at)::date`, 'ASC')
      .getRawMany<{ date: string; amountEtb: string; amountUsd: string }>();

    return rows.map((row) => ({
      date: row.date,
      amountEtb: Number(row.amountEtb),
      amountUsd: Number(row.amountUsd),
    }));
  }

  async getRecentBookings(limit: number): Promise<OverviewRecentBookingRow[]> {
    const rows = await this.bookingRepository
      .createQueryBuilder('booking')
      .leftJoin('booking.company', 'company')
      .select('booking.id', 'id')
      .addSelect('booking.reference', 'reference')
      .addSelect('COALESCE(company.name, \'—\')', 'customerLabel')
      .addSelect('booking.status', 'status')
      .addSelect('booking.priority_score', 'priorityScore')
      .addSelect('booking.total_amount', 'totalAmount')
      .addSelect('booking.payment_currency', 'paymentCurrency')
      .addSelect('booking.created_at', 'createdAt')
      .where('booking.deleted_at IS NULL')
      .orderBy('booking.created_at', 'DESC')
      .limit(limit)
      .getRawMany<{
        id: string;
        reference: string;
        customerLabel: string;
        status: string;
        priorityScore: string;
        totalAmount: string | null;
        paymentCurrency: string | null;
        createdAt: Date;
      }>();

    return rows.map((row) => ({
      id: row.id,
      reference: row.reference,
      customerLabel: row.customerLabel,
      status: row.status,
      priorityScore: Number(row.priorityScore),
      totalAmount: row.totalAmount != null ? Number(row.totalAmount) : null,
      paymentCurrency: row.paymentCurrency,
      createdAt: row.createdAt,
    }));
  }

  async getBookingsByFreightType(): Promise<{ label: string; count: number }[]> {
    const rows = await this.bookingRepository
      .createQueryBuilder('booking')
      .select('booking.freight_type', 'label')
      .addSelect('COUNT(*)::int', 'count')
      .where('booking.deleted_at IS NULL')
      .andWhere("booking.status != 'DRAFT'")
      .groupBy('booking.freight_type')
      .orderBy('count', 'DESC')
      .getRawMany<{ label: string; count: string }>();

    return rows.map((row) => ({
      label: row.label,
      count: Number(row.count),
    }));
  }

  async getBookingsByCurrency(): Promise<{ label: string; count: number }[]> {
    const rows = await this.bookingRepository
      .createQueryBuilder('booking')
      .select('booking.payment_currency', 'label')
      .addSelect('COUNT(*)::int', 'count')
      .where('booking.deleted_at IS NULL')
      .andWhere("booking.status != 'DRAFT'")
      .groupBy('booking.payment_currency')
      .orderBy('count', 'DESC')
      .getRawMany<{ label: string; count: string }>();

    return rows.map((row) => ({
      label: row.label,
      count: Number(row.count),
    }));
  }

  async getPaymentsByStatus(): Promise<{ status: string; count: number }[]> {
    const rows = await this.paymentRepository
      .createQueryBuilder('payment')
      .select('payment.status', 'status')
      .addSelect('COUNT(*)::int', 'count')
      .groupBy('payment.status')
      .orderBy('count', 'DESC')
      .getRawMany<{ status: string; count: string }>();

    return rows.map((row) => ({
      status: row.status,
      count: Number(row.count),
    }));
  }

  async getPaymentsByMethod(): Promise<
    { method: string; count: number; amountEtb: number; amountUsd: number }[]
  > {
    const rows = await this.paymentRepository
      .createQueryBuilder('payment')
      .select('payment.method', 'method')
      .addSelect('COUNT(*)::int', 'count')
      .addSelect(
        `COALESCE(SUM(payment.amount) FILTER (WHERE payment.currency = 'ETB' AND payment.status = 'success'), 0)`,
        'amountEtb',
      )
      .addSelect(
        `COALESCE(SUM(payment.amount) FILTER (WHERE payment.currency = 'USD' AND payment.status = 'success'), 0)`,
        'amountUsd',
      )
      .groupBy('payment.method')
      .orderBy('count', 'DESC')
      .getRawMany<{ method: string; count: string; amountEtb: string; amountUsd: string }>();

    return rows.map((row) => ({
      method: row.method,
      count: Number(row.count),
      amountEtb: Number(row.amountEtb),
      amountUsd: Number(row.amountUsd),
    }));
  }

  async getRevenueByCurrency(): Promise<{ currency: string; amount: number }[]> {
    const rows = await this.paymentRepository
      .createQueryBuilder('payment')
      .select('payment.currency', 'currency')
      .addSelect('COALESCE(SUM(payment.amount), 0)', 'amount')
      .where('payment.status = :status', { status: 'success' })
      .andWhere(
        `COALESCE(payment.paid_at, payment.created_at) >= date_trunc('month', CURRENT_DATE)`,
      )
      .groupBy('payment.currency')
      .getRawMany<{ currency: string; amount: string }>();

    return rows.map((row) => ({
      currency: row.currency,
      amount: Number(row.amount),
    }));
  }

  async getTrainStatusBreakdown(): Promise<{ status: string; count: number }[]> {
    return this.statusBreakdown(this.trainRepository, 'train');
  }

  async getWagonStatusBreakdown(): Promise<{ status: string; count: number }[]> {
    return this.statusBreakdown(this.wagonRepository, 'wagon');
  }

  async getContainerStatusBreakdown(): Promise<{ status: string; count: number }[]> {
    return this.statusBreakdown(this.containerRepository, 'container');
  }

  async getCargoStatusBreakdown(): Promise<{ status: string; count: number }[]> {
    return this.statusBreakdown(this.cargoRepository, 'cargo');
  }

  private async statusBreakdown(
    repository: Repository<ObjectLiteral>,
    alias: string,
  ): Promise<{ status: string; count: number }[]> {
    const rows = await repository
      .createQueryBuilder(alias)
      .select(`${alias}.status`, 'status')
      .addSelect('COUNT(*)::int', 'count')
      .where(`${alias}.deleted_at IS NULL`)
      .groupBy(`${alias}.status`)
      .orderBy('count', 'DESC')
      .getRawMany<{ status: string; count: string }>();

    return rows.map((row) => ({
      status: row.status,
      count: Number(row.count),
    }));
  }

  async getCustomerGrowthTrend(days: number): Promise<{ date: string; count: number }[]> {
    const rows = await this.customerRepository
      .createQueryBuilder('customer')
      .select(`to_char(customer.created_at::date, 'YYYY-MM-DD')`, 'date')
      .addSelect('COUNT(*)::int', 'count')
      .where('customer.deleted_at IS NULL')
      .andWhere(`customer.created_at >= CURRENT_DATE - :days::int + 1`, { days })
      .groupBy('customer.created_at::date')
      .orderBy('customer.created_at::date', 'ASC')
      .getRawMany<{ date: string; count: string }>();

    return rows.map((row) => ({
      date: row.date,
      count: Number(row.count),
    }));
  }

  async getCustomersByType(): Promise<{ label: string; count: number }[]> {
    const rows = await this.customerRepository
      .createQueryBuilder('customer')
      .select(`COALESCE(NULLIF(customer.customer_type, ''), 'Unknown')`, 'label')
      .addSelect('COUNT(*)::int', 'count')
      .where('customer.deleted_at IS NULL')
      .groupBy('customer.customer_type')
      .orderBy('count', 'DESC')
      .getRawMany<{ label: string; count: string }>();

    return rows.map((row) => ({
      label: row.label,
      count: Number(row.count),
    }));
  }

  async getTopCustomersByBookings(limit: number): Promise<{ label: string; count: number }[]> {
    const rows = await this.bookingRepository
      .createQueryBuilder('booking')
      .leftJoin('booking.company', 'company')
      .select(`COALESCE(company.name, 'Unknown')`, 'label')
      .addSelect('COUNT(*)::int', 'count')
      .where('booking.deleted_at IS NULL')
      .andWhere("booking.status != 'DRAFT'")
      .groupBy('company.name')
      .orderBy('count', 'DESC')
      .limit(limit)
      .getRawMany<{ label: string; count: string }>();

    return rows.map((row) => ({
      label: row.label,
      count: Number(row.count),
    }));
  }

  async getUsersByStatus(): Promise<{ status: string; count: number }[]> {
    const rows = await this.userRepository
      .createQueryBuilder('user')
      .select('user.status', 'status')
      .addSelect('COUNT(*)::int', 'count')
      .groupBy('user.status')
      .orderBy('count', 'DESC')
      .getRawMany<{ status: string; count: string }>();

    return rows.map((row) => ({
      status: row.status,
      count: Number(row.count),
    }));
  }

  async getEmployeeGrowthTrend(days: number): Promise<{ date: string; count: number }[]> {
    const rows = await this.employeeRepository
      .createQueryBuilder('employee')
      .select(`to_char(employee.created_at::date, 'YYYY-MM-DD')`, 'date')
      .addSelect('COUNT(*)::int', 'count')
      .where('employee.is_current = true')
      .andWhere(`employee.created_at >= CURRENT_DATE - :days::int + 1`, { days })
      .groupBy('employee.created_at::date')
      .orderBy('employee.created_at::date', 'ASC')
      .getRawMany<{ date: string; count: string }>();

    return rows.map((row) => ({
      date: row.date,
      count: Number(row.count),
    }));
  }

  async getActiveUsersBreakdown(): Promise<{ label: string; count: number }[]> {
    const [active, inactive] = await Promise.all([
      this.userRepository.count({
        where: { isActive: true, status: EUserStatus.ACCEPTED },
      }),
      this.userRepository
        .createQueryBuilder('user')
        .where('user.is_active = false OR user.status != :status', {
          status: EUserStatus.ACCEPTED,
        })
        .getCount(),
    ]);

    return [
      { label: 'Active', count: active },
      { label: 'Inactive', count: inactive },
    ];
  }
}