'use client'

import { useState, useEffect } from 'react'
import { teacherUnavailableDayApi, teachersApi } from '@/lib/stundenplan/api'
import type { TeacherUnavailableDay, TimetableTeacher } from '@/app/stundenplan/types'
import { useConstraintCrud, ConstraintShell, useShellStyles, DAYS, dayLabel } from './_shell'

type FormState = Omit<TeacherUnavailableDay, 'id' | 'created_by_user_id' | 'created_at'>

const initialForm: FormState = {
  teacher_id: '',
  day_of_week: 1,
  is_hard: true,
  weight: 100,
  active: true,
  note: '',
}

export function TeacherUnavailableDayEditor() {
  const styles = useShellStyles()
  const crud = useConstraintCrud<TeacherUnavailableDay, FormState>(teacherUnavailableDayApi, initialForm)
  const [teachers, setTeachers] = useState<TimetableTeacher[]>([])

  useEffect(() => { teachersApi.list().then(setTeachers).catch(() => setTeachers([])) }, [])

  const teacherLabel = (id: string): string => {
    const t = teachers.find(x => x.id === id)
    return t ? `${t.last_name}, ${t.first_name} (${t.short_code})` : id.slice(0, 8) + '…'
  }

  return (
    <ConstraintShell
      testId="teacher-unavailable-day-editor"
      title="Lehrer: Tag nicht verfuegbar"
      description={"Beispiel: Lehrer X kann Montags nie."}
      newLabel="+ Neue Regel"
      newDisabled={teachers.length === 0}
      prereqWarning={teachers.length === 0 ? 'Zuerst Lehrer anlegen, dann koennen Regeln vergeben werden.' : null}
      emptyText="Keine Regeln vorhanden."
      tableHeaders={['Lehrer', 'Tag', 'Hart', 'Weight', 'Aktiv', 'Notiz']}
      state={crud}
      formBody={
        <>
          <div className="grid grid-cols-1 md:grid-cols-3 gap-3">
            <div>
              <label className="block text-sm mb-1 opacity-70">Lehrer</label>
              <select required value={crud.form.teacher_id} onChange={e => crud.setForm({ ...crud.form, teacher_id: e.target.value })} className={`w-full px-3 py-2 rounded-lg border ${styles.inputClass}`}>
                <option value="">— bitte waehlen —</option>
                {teachers.map(t => <option key={t.id} value={t.id}>{t.last_name}, {t.first_name}</option>)}
              </select>
            </div>
            <div>
              <label className="block text-sm mb-1 opacity-70">Wochentag</label>
              <select value={crud.form.day_of_week} onChange={e => crud.setForm({ ...crud.form, day_of_week: parseInt(e.target.value) })} className={`w-full px-3 py-2 rounded-lg border ${styles.inputClass}`}>
                {DAYS.map(d => <option key={d.v} value={d.v}>{d.label}</option>)}
              </select>
            </div>
            <div>
              <label className="block text-sm mb-1 opacity-70">Gewichtung (0-100)</label>
              <input type="number" min={0} max={100} value={crud.form.weight} onChange={e => crud.setForm({ ...crud.form, weight: parseInt(e.target.value) || 0 })} className={`w-full px-3 py-2 rounded-lg border ${styles.inputClass}`} />
            </div>
            <div className="flex items-center gap-2">
              <input type="checkbox" id="is_hard" checked={crud.form.is_hard} onChange={e => crud.setForm({ ...crud.form, is_hard: e.target.checked })} className="w-5 h-5" />
              <label htmlFor="is_hard" className="text-sm">Harte Regel (muss eingehalten werden)</label>
            </div>
            <div className="flex items-center gap-2">
              <input type="checkbox" id="active" checked={crud.form.active} onChange={e => crud.setForm({ ...crud.form, active: e.target.checked })} className="w-5 h-5" />
              <label htmlFor="active" className="text-sm">Aktiv</label>
            </div>
            <div className="flex items-end">
              <button type="submit" disabled={crud.submitting} className={styles.submitBtn}>
                {crud.submitting ? 'Speichert...' : 'Anlegen'}
              </button>
            </div>
          </div>
          <div className="mt-3">
            <label className="block text-sm mb-1 opacity-70">Begruendung (optional)</label>
            <input value={crud.form.note || ''} onChange={e => crud.setForm({ ...crud.form, note: e.target.value })} placeholder="z.B. Zweitjob in Praxis" className={`w-full px-3 py-2 rounded-lg border ${styles.inputClass}`} />
          </div>
        </>
      }
      renderRow={(item) => {
        const c = item as TeacherUnavailableDay
        return (
          <tr key={c.id} className={styles.rowClass}>
            <td className="px-4 py-3 font-medium">{teacherLabel(c.teacher_id)}</td>
            <td className="px-4 py-3">{dayLabel(c.day_of_week)}</td>
            <td className="px-4 py-3">{c.is_hard ? '✓' : '—'}</td>
            <td className="px-4 py-3">{c.weight}</td>
            <td className="px-4 py-3">{c.active ? '✓' : '—'}</td>
            <td className="px-4 py-3 text-sm opacity-70">{c.note || '—'}</td>
            <td className="px-4 py-3 text-right">
              <button onClick={() => crud.remove(c.id)} className={styles.deleteBtn}>Loeschen</button>
            </td>
          </tr>
        )
      }}
    />
  )
}