/**
 * Operations Dashboard Service — Tickets e Cobertura de PROCs
 * @author Descomplicar® | @link descomplicar.pt | @copyright 2026
 */
import db from '../db.js'
import type { RowDataPacket } from 'mysql2'

// ---------------------------------------------------------------------------
// Tipos
// ---------------------------------------------------------------------------

export interface OperationsDashboard {
  tickets: {
    open: number
    high_priority: number
    avg_response_hours: number
    by_department: { dept: string; count: number }[]
  }
  procedures: {
    total: number
    departments: number
    coverage: { dept: string; procs: number; total_expected: number; pct: number }[]
  }
}

// ---------------------------------------------------------------------------
// Dados estáticos — cobertura de PROCs por departamento
// ---------------------------------------------------------------------------

const PROC_COVERAGE = [
  { dept: 'D1 — Comercial',         procs: 5,  total_expected: 8  },
  { dept: 'D2 — Suporte',           procs: 3,  total_expected: 6  },
  { dept: 'D3 — Contabilidade',     procs: 3,  total_expected: 5  },
  { dept: 'D4 — RH',                procs: 1,  total_expected: 4  },
  { dept: 'D5 — Marketing',         procs: 5,  total_expected: 8  },
  { dept: 'D6 — Gestão',            procs: 8,  total_expected: 10 },
  { dept: 'D7 — Tecnologia',        procs: 18, total_expected: 20 },
  { dept: 'Cross-Departamental',    procs: 5,  total_expected: 6  },
]

// ---------------------------------------------------------------------------
// Query principal
// ---------------------------------------------------------------------------

export async function getOperationsDashboard(): Promise<OperationsDashboard> {
  // Queries paralelas para melhor performance
  const [
    ticketsAbertosResult,
    ticketsAltaPrioridadeResult,
    ticketsPorDepartamentoResult,
    tempoMedioRespostaResult,
  ] = await Promise.all([
    // a) Total de tickets abertos (status 1=Open, 2=In Progress, 3=Answered)
    db.query<RowDataPacket[]>(
      `SELECT COUNT(*) as count
       FROM tbltickets
       WHERE status IN ('1','2','3')`
    ),

    // b) Tickets de alta prioridade ainda abertos (priority 2=High, 3=Urgent)
    db.query<RowDataPacket[]>(
      `SELECT COUNT(*) as count
       FROM tbltickets
       WHERE priority IN (2,3)
         AND status IN ('1','2','3')`
    ),

    // c) Tickets abertos agrupados por departamento
    db.query<RowDataPacket[]>(
      `SELECT d.name as dept, COUNT(t.ticketid) as count
       FROM tbltickets t
       LEFT JOIN tbldepartments d ON t.department = d.departmentid
       WHERE t.status IN ('1','2','3')
       GROUP BY d.departmentid, d.name
       ORDER BY count DESC`
    ),

    // d) Tempo médio de resposta em horas (últimos 90 dias)
    db.query<RowDataPacket[]>(
      `SELECT ROUND(AVG(TIMESTAMPDIFF(HOUR, t.date, t.lastreply)), 1) as avg_hours
       FROM tbltickets t
       WHERE t.lastreply IS NOT NULL
         AND t.lastreply != '0000-00-00 00:00:00'
         AND t.date > DATE_SUB(CURDATE(), INTERVAL 90 DAY)`
    ),
  ])

  // Extrair valores das queries
  const ticketsAbertos       = (ticketsAbertosResult[0][0] as RowDataPacket)?.count ?? 0
  const ticketsAltaPrioridade = (ticketsAltaPrioridadeResult[0][0] as RowDataPacket)?.count ?? 0
  const avgResponseHours     = (tempoMedioRespostaResult[0][0] as RowDataPacket)?.avg_hours ?? 0

  const byDepartment = (ticketsPorDepartamentoResult[0] as RowDataPacket[]).map(row => ({
    dept:  (row.dept as string) || 'Sem departamento',
    count: Number(row.count) || 0,
  }))

  // Calcular cobertura em percentagem
  const coverage = PROC_COVERAGE.map(item => ({
    dept:           item.dept,
    procs:          item.procs,
    total_expected: item.total_expected,
    pct:            Math.round((item.procs / item.total_expected) * 100),
  }))

  const totalProcs       = PROC_COVERAGE.reduce((sum, d) => sum + d.procs, 0)
  const totalDepartments = PROC_COVERAGE.filter(d => d.dept.startsWith('D')).length

  return {
    tickets: {
      open:              Number(ticketsAbertos),
      high_priority:     Number(ticketsAltaPrioridade),
      avg_response_hours: Number(avgResponseHours),
      by_department:     byDepartment,
    },
    procedures: {
      total:       totalProcs,
      departments: totalDepartments,
      coverage,
    },
  }
}