'use client'

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

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

const initialForm: FormState = {
  teacher_id: '', day_of_week: 2, start_time: '13:00', end_time: '17:00',
  is_hard: true, weight: 100, active: true, note: '',
}

export function TeacherUnavailableWindowEditor() {
  const styles = useShellStyles()
  const crud = useConstraintCrud<TeacherUnavailableWindow, FormState>(teacherUnavailableWindowApi, 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}` : id.slice(0, 8) + '…'
  }

  return (
    <ConstraintShell
      testId="teacher-unavailable-window-editor"
      title="Lehrer: Zeitfenster nicht verfuegbar"
      description={"Beispiel: Lehrer Z Dienstags 13:00–17:00 nicht."}
      newLabel="+ Neue Regel"
      newDisabled={teachers.length === 0}
      prereqWarning={teachers.length === 0 ? 'Zuerst Lehrer anlegen.' : null}
      emptyText="Keine Regeln vorhanden."
      tableHeaders={['Lehrer', 'Tag', 'Zeitfenster', 'Hart', 'Notiz']}
      state={crud}
      formBody={
        <>
          <div className="grid grid-cols-1 md:grid-cols-4 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">Von</label>
              <input type="time" required value={crud.form.start_time} onChange={e => crud.setForm({ ...crud.form, start_time: e.target.value })} className={`w-full px-3 py-2 rounded-lg border ${styles.inputClass}`} />
            </div>
            <div>
              <label className="block text-sm mb-1 opacity-70">Bis</label>
              <input type="time" required value={crud.form.end_time} onChange={e => crud.setForm({ ...crud.form, end_time: e.target.value })} 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_w" 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_w" className="text-sm">Harte Regel</label>
            </div>
            <div>
              <label className="block text-sm mb-1 opacity-70">Weight (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="md:col-span-2 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 })} className={`w-full px-3 py-2 rounded-lg border ${styles.inputClass}`} />
          </div>
        </>
      }
      renderRow={(item) => {
        const c = item as TeacherUnavailableWindow
        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.start_time}–{c.end_time}</td>
            <td className="px-4 py-3">{c.is_hard ? '✓' : '—'}</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>
        )
      }}
    />
  )
}
