import type { DayInfo, Person } from './types'
import { getCzechHolidays } from './holidays'

const MONTH_NAMES: Record<number, string> = {
  1:'Leden',2:'Únor',3:'Březen',4:'Duben',5:'Květen',6:'Červen',
  7:'Červenec',8:'Srpen',9:'Září',10:'Říjen',11:'Listopad',12:'Prosinec',
}

interface FpdResult {
  personId: string
  name: string
  note?: string
  workedHours: number
  fpd: number
  diff: number // positive = over, negative = under
}

function getHoursForValue(v: string): number {
  if (v === 'A' || v === 'B') return 12
  const num = parseFloat(v)
  if (!isNaN(num) && num > 0) return num
  return 0
}

export function computeFpd(
  month: number,
  year: number,
  dayIndex: DayInfo[],
  people: Person[],
): { fpd: number; workDays: number; results: FpdResult[] } {
  const holidays = getCzechHolidays(year)
  const holidaySet = new Set(holidays.filter(h => h.month === month).map(h => h.day))

  // Count working days in month
  const monthDays = dayIndex.filter(d => d.month === month && d.year === year)
  let workDays = 0
  for (const d of monthDays) {
    if (!d.weekend && !holidaySet.has(d.day)) workDays++
  }
  const fpd = workDays * 8

  // Check TKB people only
  const tkbPeople = people.filter(p => p.group === 'TKB')
  const results: FpdResult[] = []

  for (const person of tkbPeople) {
    let workedHours = 0
    for (const d of monthDays) {
      const cellData = person.data[String(d.idx)]
      const value = cellData?.v
      if (value) {
        workedHours += getHoursForValue(value)
      }
    }
    const diff = workedHours - fpd
    results.push({
      personId: person.id,
      name: person.name,
      note: person.note,
      workedHours,
      fpd,
      diff,
    })
  }

  return { fpd, workDays, results }
}

interface FpdModalProps {
  month: number
  year: number
  dayIndex: DayInfo[]
  people: Person[]
  onClose: () => void
  onExportDochazka?: () => void
}

export function FpdModal({ month, year, dayIndex, people, onClose, onExportDochazka }: FpdModalProps) {
  const { fpd, workDays, results } = computeFpd(month, year, dayIndex, people)
  const under = results.filter(r => r.diff < 0)
  const okOrOver = results.filter(r => r.diff >= 0)

  return (
    <div className="fixed inset-0 z-[300] flex items-center justify-center bg-black/50" onClick={onClose}>
      <div className="bg-slate-800 border border-slate-600 rounded-xl shadow-2xl w-full max-w-lg max-h-[80vh] flex flex-col" onClick={e => e.stopPropagation()}>
        <div className="flex items-center justify-between px-5 py-3 border-b border-slate-700">
          <h2 className="text-sm font-semibold text-slate-200">
            Kontrola FPD — {MONTH_NAMES[month]} {year}
          </h2>
          <button onClick={onClose} className="text-slate-400 hover:text-slate-200 cursor-pointer text-lg">&times;</button>
        </div>

        <div className="px-5 py-3 border-b border-slate-700 text-xs text-slate-400">
          Pracovních dnů: <span className="text-slate-200 font-semibold">{workDays}</span>
          <span className="mx-2">|</span>
          FPD: <span className="text-slate-200 font-semibold">{fpd} h</span>
          <span className="mx-2">|</span>
          Pohotovost TKB: <span className="text-slate-200 font-semibold">{results.length} osob</span>
        </div>

        <div className="overflow-y-auto flex-1 px-5 py-3">
          {under.length === 0 ? (
            <div className="text-center py-4 text-green-400 text-sm font-semibold">
              ✓ Nikdo nemá nedostatek hodin
            </div>
          ) : (
            <>
              <div className="text-xs text-red-400 uppercase tracking-wider mb-2 font-semibold">Chybí hodiny ({under.length})</div>
              <div className="space-y-1 mb-4">
                {under.map(r => (
                  <div
                    key={r.personId}
                    className="flex items-center justify-between px-3 py-2 rounded text-xs bg-red-900/30 border border-red-700/50"
                  >
                    <span className="text-slate-200">
                      {r.name}
                      {r.note && <span className="text-slate-500 ml-1">({r.note})</span>}
                    </span>
                    <span className="flex items-center gap-2">
                      <span className="text-slate-400">{r.workedHours}h / {r.fpd}h</span>
                      <span className="font-bold text-red-400">{r.diff}h</span>
                    </span>
                  </div>
                ))}
              </div>
            </>
          )}

          <div className="text-xs text-slate-500 uppercase tracking-wider mb-2">Ostatní ({okOrOver.length})</div>
          <div className="space-y-1">
            {okOrOver.map(r => (
              <div
                key={r.personId}
                className={`flex items-center justify-between px-3 py-2 rounded text-xs
                  ${r.diff > 0 ? 'bg-slate-700/30 border border-slate-600/50' : 'bg-green-900/20 border border-green-700/30'}`}
              >
                <span className="text-slate-200">
                  {r.name}
                  {r.note && <span className="text-slate-500 ml-1">({r.note})</span>}
                </span>
                <span className="flex items-center gap-2">
                  <span className="text-slate-400">{r.workedHours}h / {r.fpd}h</span>
                  <span className={`font-bold ${r.diff > 0 ? 'text-slate-300' : 'text-green-400'}`}>
                    {r.diff > 0 ? `+${r.diff}h` : '✓'}
                  </span>
                </span>
              </div>
            ))}
          </div>
        </div>

        {onExportDochazka && (
          <div className="px-5 py-3 border-t border-slate-700 flex justify-end">
            <button
              onClick={onExportDochazka}
              className="px-4 py-2 rounded text-xs bg-green-700/70 text-green-100 border border-green-600
                         hover:bg-green-600/70 cursor-pointer transition-colors font-semibold"
            >
              ↓ Stáhnout docházku (Excel)
            </button>
          </div>
        )}
      </div>
    </div>
  )
}