import {
  Controller,
  Get,
} from '@nestjs/common'
import { InjectRepository } from '@nestjs/typeorm'
import { Repository } from 'typeorm'

import { TransactionEntity } from '@/src/entities/transaction.entity'
import { SubscriptionEntity } from '@/src/entities/subscription.entity'
import { PayoutEntity } from '@/src/entities/payout.entity'
import { EarningsEntryEntity } from '@/src/entities/earnings-entry.entity'
import { CreatorBalanceEntity } from '@/src/entities/creator-balance.entity'
import { TransactionStatus } from '@/providers/transaction.types'
import { SubscriptionStatus } from '@/providers/subscription.types'
import { PayoutStatus } from '@/providers/transaction.types'

/**
 * Admin Analytics Controller
 *
 * Read-only analytics endpoints for the admin dashboard.
 * Matches frontend adminAnalyticsApi contract.
 *
 * Routes:
 * - GET /admin/analytics/dashboard      — overview stats
 * - GET /admin/analytics/revenue        — revenue breakdown
 * - GET /admin/analytics/subscriptions  — subscription stats
 * - GET /admin/analytics/transactions   — transaction stats
 * - GET /admin/analytics/payouts        — payout stats
 */
@Controller('admin/analytics')
export class AdminAnalyticsController {
  constructor(
    @InjectRepository(TransactionEntity)
    private readonly transactionRepository: Repository<TransactionEntity>,
    @InjectRepository(SubscriptionEntity)
    private readonly subscriptionRepository: Repository<SubscriptionEntity>,
    @InjectRepository(PayoutEntity)
    private readonly payoutRepository: Repository<PayoutEntity>,
    @InjectRepository(EarningsEntryEntity)
    private readonly earningsRepository: Repository<EarningsEntryEntity>,
    @InjectRepository(CreatorBalanceEntity)
    private readonly balanceRepository: Repository<CreatorBalanceEntity>,
  ) {}

  /**
   * GET /admin/analytics/dashboard
   *
   * High-level overview stats for the admin dashboard.
   */
  @Get('dashboard')
  async getDashboard() {
    const [
      totalTransactions,
      totalSubscriptions,
      activeSubscriptions,
      totalPayouts,
      pendingPayouts,
    ] = await Promise.all([
      this.transactionRepository.count(),
      this.subscriptionRepository.count(),
      this.subscriptionRepository.count({ where: { status: SubscriptionStatus.ACTIVE } }),
      this.payoutRepository.count(),
      this.payoutRepository.count({ where: { status: PayoutStatus.PENDING } }),
    ])

    const revenueResult = await this.transactionRepository
      .createQueryBuilder('t')
      .select('COALESCE(SUM(t.amountCents), 0)', 'totalRevenueCents')
      .where('t.status = :status', { status: TransactionStatus.COMPLETED })
      .getRawOne()

    const earningsResult = await this.earningsRepository
      .createQueryBuilder('e')
      .select([
        'COALESCE(SUM(e.grossCents), 0) AS "totalGrossCents"',
        'COALESCE(SUM(e.platformFeeCents), 0) AS "totalPlatformFeeCents"',
        'COALESCE(SUM(e.netCents), 0) AS "totalCreatorNetCents"',
      ])
      .getRawOne()

    return {
      totalTransactions,
      totalSubscriptions,
      activeSubscriptions,
      totalPayouts,
      pendingPayouts,
      totalRevenueCents: Number(revenueResult?.totalRevenueCents || 0),
      totalGrossCents: Number(earningsResult?.totalGrossCents || 0),
      totalPlatformFeeCents: Number(earningsResult?.totalPlatformFeeCents || 0),
      totalCreatorNetCents: Number(earningsResult?.totalCreatorNetCents || 0),
    }
  }

  /**
   * GET /admin/analytics/revenue
   *
   * Revenue breakdown by type and time period.
   */
  @Get('revenue')
  async getRevenue() {
    // Revenue by earnings type
    const byType = await this.earningsRepository
      .createQueryBuilder('e')
      .select([
        'e.type AS type',
        'COUNT(*) AS count',
        'COALESCE(SUM(e.grossCents), 0) AS "grossCents"',
        'COALESCE(SUM(e.platformFeeCents), 0) AS "platformFeeCents"',
        'COALESCE(SUM(e.netCents), 0) AS "netCents"',
      ])
      .groupBy('e.type')
      .getRawMany()

    // Revenue last 30 days (daily)
    const daily = await this.earningsRepository
      .createQueryBuilder('e')
      .select([
        "DATE_TRUNC('day', e.created_at) AS date",
        'COALESCE(SUM(e.grossCents), 0) AS "grossCents"',
        'COALESCE(SUM(e.platformFeeCents), 0) AS "platformFeeCents"',
      ])
      .where("e.created_at >= NOW() - INTERVAL '30 days'")
      .groupBy("DATE_TRUNC('day', e.created_at)")
      .orderBy('date', 'ASC')
      .getRawMany()

    return { byType, daily }
  }

  /**
   * GET /admin/analytics/subscriptions
   *
   * Subscription stats: counts by status.
   */
  @Get('subscriptions')
  async getSubscriptions() {
    const byStatus = await this.subscriptionRepository
      .createQueryBuilder('s')
      .select([
        's.status AS status',
        'COUNT(*) AS count',
      ])
      .groupBy('s.status')
      .getRawMany()

    const totalActive = await this.subscriptionRepository.count({
      where: { status: SubscriptionStatus.ACTIVE },
    })

    const totalCancelled = await this.subscriptionRepository.count({
      where: { status: SubscriptionStatus.CANCELLED },
    })

    // MRR calculation: sum of active subscription prices
    const mrrResult = await this.subscriptionRepository
      .createQueryBuilder('s')
      .select('COALESCE(SUM(s.priceCents), 0)', 'mrrCents')
      .where('s.status = :status', { status: SubscriptionStatus.ACTIVE })
      .getRawOne()

    return {
      byStatus,
      totalActive,
      totalCancelled,
      mrrCents: Number(mrrResult?.mrrCents || 0),
    }
  }

  /**
   * GET /admin/analytics/transactions
   *
   * Transaction stats: counts and totals by status and type.
   */
  @Get('transactions')
  async getTransactions() {
    const byStatus = await this.transactionRepository
      .createQueryBuilder('t')
      .select([
        't.status AS status',
        'COUNT(*) AS count',
        'COALESCE(SUM(t.amountCents), 0) AS "totalCents"',
      ])
      .groupBy('t.status')
      .getRawMany()

    const byType = await this.transactionRepository
      .createQueryBuilder('t')
      .select([
        't.type AS type',
        'COUNT(*) AS count',
        'COALESCE(SUM(t.amountCents), 0) AS "totalCents"',
      ])
      .groupBy('t.type')
      .getRawMany()

    return { byStatus, byType }
  }

  /**
   * GET /admin/analytics/payouts
   *
   * Payout stats: counts and totals by status.
   */
  @Get('payouts')
  async getPayouts() {
    const byStatus = await this.payoutRepository
      .createQueryBuilder('p')
      .select([
        'p.status AS status',
        'COUNT(*) AS count',
        'COALESCE(SUM(p.amountCents), 0) AS "totalCents"',
      ])
      .groupBy('p.status')
      .getRawMany()

    const totalPaidOutCents = await this.payoutRepository
      .createQueryBuilder('p')
      .select('COALESCE(SUM(p.amountCents), 0)', 'total')
      .where('p.status = :status', { status: PayoutStatus.COMPLETED })
      .getRawOne()

    const totalCreatorBalances = await this.balanceRepository
      .createQueryBuilder('b')
      .select([
        'COALESCE(SUM(b.availableCents), 0) AS "totalAvailableCents"',
        'COALESCE(SUM(b.pendingCents), 0) AS "totalPendingCents"',
        'COUNT(*) AS "totalCreators"',
      ])
      .getRawOne()

    return {
      byStatus,
      totalPaidOutCents: Number(totalPaidOutCents?.total || 0),
      totalAvailableCents: Number(totalCreatorBalances?.totalAvailableCents || 0),
      totalPendingCents: Number(totalCreatorBalances?.totalPendingCents || 0),
      totalCreators: Number(totalCreatorBalances?.totalCreators || 0),
    }
  }
}