import 'server-only'

import { getSupabaseAdminClient } from './supabase-admin'

/** Monthly list price per tier, in USD. */
const TIER_MONTHLY_USD: Record<'pro' | 'pro_plus' | 'free', number> = {
  pro: 9.9,
  pro_plus: 19.9,
  free: 0,
}

export interface SubscriptionRevenue {
  mrrUsd: number
  arrUsd: number
  activeCount: number
  tierBreakdown: { pro: number; pro_plus: number; free: number }
}

/**
 * Aggregates real subscription revenue from Supabase.
 * Only status === 'active' subscriptions contribute to MRR/ARR.
 * MRR = Σ(monthly price of each active subscription's tier); ARR = MRR * 12.
 */
export async function fetchSubscriptionRevenue(): Promise<SubscriptionRevenue> {
  const supabase = await getSupabaseAdminClient('manager')

  const rows: Array<Record<string, unknown>> = []
  for (let page = 0; page < 100; page += 1) {
    const { data, error } = await supabase
      .from('subscriptions')
      .select('tier, status')
      .range(page * 1000, page * 1000 + 999)
    if (error) throw new Error('Supabase subscription revenue query failed')
    rows.push(...((data ?? []) as Array<Record<string, unknown>>))
    if ((data?.length ?? 0) < 1000) break
    if (page === 99) throw new Error('Supabase subscription directory exceeds the supported administrative window')
  }

  const tierBreakdown = { pro: 0, pro_plus: 0, free: 0 }
  let mrrUsd = 0
  let activeCount = 0

  for (const row of rows) {
    if (row.status !== 'active') continue
    activeCount += 1
    const tier = row.tier
    if (tier === 'pro' || tier === 'pro_plus' || tier === 'free') {
      tierBreakdown[tier] += 1
      mrrUsd += TIER_MONTHLY_USD[tier]
    }
  }

  mrrUsd = Math.round(mrrUsd * 100) / 100
  const arrUsd = Math.round(mrrUsd * 12 * 100) / 100

  return { mrrUsd, arrUsd, activeCount, tierBreakdown }
}