import type { DB } from './db'
import { duesAging } from './repos-reports'
import { ticketCounts } from './repos-tickets'
import { queueCounts } from './repos-reminders'
import { renewalsDue } from './repos-renewals'
import { smsLowCount } from './repos-sms'

/**
 * Owner MIS cockpit (D27): one read-only screen of the numbers the owner checks —
 * this month vs last for billing + collections, total outstanding, open pipeline value,
 * renewals due, open tickets, reminder queue. Composes the SAME repo aggregates the
 * Reports/Dashboard pages use, so the figures reconcile exactly. Integer paise throughout.
 */

function monthStart(iso: string): string { return iso.slice(0, 7) + '-01' }
function addMonths(ymd: string, n: number): string {
  const [y, m] = ymd.split('-').map(Number)
  const d = new Date(Date.UTC(y!, (m! - 1) + n, 1))
  return d.toISOString().slice(0, 10)
}

export interface MisCockpit {
  today: string; thisMonth: string; lastMonth: string
  invoicedThisPaise: number; invoicedLastPaise: number
  creditNoteThisPaise: number
  collectedThisPaise: number; collectedLastPaise: number
  outstandingPaise: number; outstandingClients: number
  pipelineCount: number; pipelineValuePaise: number
  renewals30Count: number; renewals30Paise: number
  tickets: { open: number; inProgress: number; waiting: number }
  reminders: { queued: number; failed: number }
  smsLow: number; smsThreshold: number
}

const sum = async (db: DB, sql: string, ...a: unknown[]): Promise<number> =>
  ((await db.get<{ n: number }>(sql, ...a))!).n

export async function misCockpit(db: DB, today: string): Promise<MisCockpit> {
  const thisMonth = monthStart(today)
  const lastMonth = addMonths(thisMonth, -1)
  const nextMonth = addMonths(thisMonth, 1)

  // Billed (issued invoices, non-cancelled) by doc_date month.
  const invoicedThis = await sum(db,
    `SELECT COALESCE(SUM(payable_paise),0) AS n FROM document
     WHERE doc_type='INVOICE' AND doc_no IS NOT NULL AND status<>'cancelled' AND doc_date>=? AND doc_date<?`,
    thisMonth, nextMonth)
  const invoicedLast = await sum(db,
    `SELECT COALESCE(SUM(payable_paise),0) AS n FROM document
     WHERE doc_type='INVOICE' AND doc_no IS NOT NULL AND status<>'cancelled' AND doc_date>=? AND doc_date<?`,
    lastMonth, thisMonth)
  const cnThis = await sum(db,
    `SELECT COALESCE(SUM(payable_paise),0) AS n FROM document
     WHERE doc_type='CREDIT_NOTE' AND doc_no IS NOT NULL AND status<>'cancelled' AND doc_date>=? AND doc_date<?`,
    thisMonth, nextMonth)

  // Cash received by received_on month.
  const collectedThis = await sum(db, `SELECT COALESCE(SUM(amount_paise),0) AS n FROM payment WHERE received_on>=? AND received_on<?`, thisMonth, nextMonth)
  const collectedLast = await sum(db, `SELECT COALESCE(SUM(amount_paise),0) AS n FROM payment WHERE received_on>=? AND received_on<?`, lastMonth, thisMonth)

  // Outstanding = the dues-aging total (same computation the Reports page shows).
  const dues = await duesAging(db, today)
  const outstandingPaise = dues.reduce((s, r) => s + r.totalPaise, 0)

  // Open pipeline = issued/draft quotes+proformas not yet won/lost.
  const pipelineCount = await sum(db,
    `SELECT COUNT(*) AS n FROM document
     WHERE doc_type IN ('QUOTATION','PROFORMA') AND status IN ('draft','sent','accepted')`)
  const pipelineValuePaise = await sum(db,
    `SELECT COALESCE(SUM(payable_paise),0) AS n FROM document
     WHERE doc_type IN ('QUOTATION','PROFORMA') AND status IN ('draft','sent','accepted')`)

  // Renewals in the next 30 days (modules + AMC), reusing the renewals repo.
  const to30 = new Date(Date.parse(today) + 30 * 86_400_000).toISOString().slice(0, 10)
  const renewals = await renewalsDue(db, today, to30, today)
  const renewals30Paise = renewals.reduce((s, r) => s + (r.amountPaise ?? 0), 0)

  const tc = await ticketCounts(db)
  const qc = await queueCounts(db)
  const sms = await smsLowCount(db)

  return {
    today, thisMonth, lastMonth,
    invoicedThisPaise: invoicedThis, invoicedLastPaise: invoicedLast, creditNoteThisPaise: cnThis,
    collectedThisPaise: collectedThis, collectedLastPaise: collectedLast,
    outstandingPaise, outstandingClients: dues.length,
    pipelineCount, pipelineValuePaise,
    renewals30Count: renewals.length, renewals30Paise,
    tickets: { open: tc['open'] ?? 0, inProgress: tc['in_progress'] ?? 0, waiting: tc['waiting'] ?? 0 },
    reminders: { queued: qc.queued, failed: qc.failed },
    smsLow: sms.low, smsThreshold: sms.threshold,
  }
}