import { useEffect, useState } from 'react'
import { scheduleCalendar, createSchedule, scheduleDetail, deleteSchedule } from '../../api/uiws'
import { PageHeader, Panel, Button, Modal, FormField, Input, Spinner } from '../../components/uiws/ui'

interface Sched { scheduleId: number; title: string; startDt: string; endDt: string; scheType: string; importanceCd?: string }

const WEEK = ['일', '월', '화', '수', '목', '금', '토']

export default function ScheduleCalendar() {
  const [base, setBase] = useState(new Date())
  const [type, setType] = useState<'PERSONAL' | 'DEPT'>('PERSONAL')
  const [items, setItems] = useState<Sched[]>([])
  const [loading, setLoading] = useState(false)
  const [showForm, setShowForm] = useState<string | null>(null) // date string
  const [detail, setDetail] = useState<any>(null)

  const ym = `${base.getFullYear()}-${String(base.getMonth() + 1).padStart(2, '0')}`

  const load = async () => {
    setLoading(true)
    try {
      const res = await scheduleCalendar({ type, view: 'month', baseDate: `${ym}-01` })
      setItems(res.data.data ?? [])
    } finally {
      setLoading(false)
    }
  }
  useEffect(() => { load() }, [ym, type])

  const first = new Date(base.getFullYear(), base.getMonth(), 1)
  const startPad = first.getDay()
  const daysInMonth = new Date(base.getFullYear(), base.getMonth() + 1, 0).getDate()
  const cells: (number | null)[] = [...Array(startPad).fill(null), ...Array.from({ length: daysInMonth }, (_, i) => i + 1)]

  const byDay = (d: number) => {
    const ds = `${ym}-${String(d).padStart(2, '0')}`
    return items.filter(s => (s.startDt ?? '').slice(0, 10) <= ds && ds <= (s.endDt ?? '').slice(0, 10))
  }

  const move = (delta: number) => setBase(new Date(base.getFullYear(), base.getMonth() + delta, 1))

  return (
    <div className="uiws-scope">
      <PageHeader title="일정" subtitle="UIWS 이식 · 개인/부서 일정 달력"
        actions={<Button onClick={() => setShowForm(`${ym}-01`)}>+ 일정 등록</Button>} />

      <Panel style={{ display: 'flex', gap: 10, alignItems: 'center', marginBottom: 16 }}>
        <Button variant="ghost" onClick={() => move(-1)}>‹ 이전</Button>
        <div style={{ fontWeight: 700, minWidth: 130, textAlign: 'center', color: 'var(--uiws-text)' }}>{ym}</div>
        <Button variant="ghost" onClick={() => move(1)}>다음 ›</Button>
        <div style={{ flex: 1 }} />
        <Button variant={type === 'PERSONAL' ? 'primary' : 'ghost'} onClick={() => setType('PERSONAL')}>개인</Button>
        <Button variant={type === 'DEPT' ? 'primary' : 'ghost'} onClick={() => setType('DEPT')}>부서</Button>
      </Panel>

      {loading ? <Spinner /> : (
        <div style={{ background: 'var(--uiws-surface)', border: '1px solid var(--uiws-border)', borderRadius: 12, overflow: 'hidden' }}>
          <div style={{ display: 'grid', gridTemplateColumns: 'repeat(7,1fr)' }}>
            {WEEK.map((w, i) => (
              <div key={w} style={{ padding: '10px 0', textAlign: 'center', fontSize: 12, fontWeight: 600,
                color: i === 0 ? 'var(--uiws-danger)' : 'var(--uiws-text-muted)', borderBottom: '1px solid var(--uiws-border)' }}>{w}</div>
            ))}
            {cells.map((d, i) => (
              <div key={i} onClick={() => d && setShowForm(`${ym}-${String(d).padStart(2, '0')}`)}
                style={{ minHeight: 96, padding: 6, borderRight: '1px solid var(--uiws-border)', borderBottom: '1px solid var(--uiws-border)',
                  cursor: d ? 'pointer' : 'default' }}>
                {d && <div style={{ fontSize: 12, color: 'var(--uiws-text-muted)', marginBottom: 4 }}>{d}</div>}
                {d && byDay(d).slice(0, 3).map(s => (
                  <div key={s.scheduleId} onClick={e => { e.stopPropagation(); scheduleDetail(s.scheduleId).then(r => setDetail(r.data.data)) }}
                    style={{ fontSize: 11, padding: '2px 6px', borderRadius: 6, marginBottom: 3,
                      background: 'var(--uiws-primary-soft)', color: 'var(--uiws-primary)', overflow: 'hidden', whiteSpace: 'nowrap', textOverflow: 'ellipsis' }}>
                    {s.title}
                  </div>
                ))}
              </div>
            ))}
          </div>
        </div>
      )}

      {showForm && <ScheduleForm date={showForm} type={type} onClose={() => setShowForm(null)} onSaved={() => { setShowForm(null); load() }} />}
      {detail && <ScheduleDetailModal detail={detail} onClose={() => setDetail(null)} onDeleted={() => { setDetail(null); load() }} />}
    </div>
  )
}

function ScheduleForm({ date, type, onClose, onSaved }: { date: string; type: string; onClose: () => void; onSaved: () => void }) {
  const [title, setTitle] = useState('')
  const [startDt, setStartDt] = useState(`${date}T09:00:00`)
  const [endDt, setEndDt] = useState(`${date}T18:00:00`)
  const [content, setContent] = useState('')
  const [err, setErr] = useState('')
  const save = async () => {
    setErr('')
    try {
      await createSchedule({ scheType: type, title, startDt, endDt, content, attachmentIds: [] })
      onSaved()
    } catch (e: any) { setErr(e?.response?.data?.message || '저장 실패') }
  }
  return (
    <Modal title="일정 등록" onClose={onClose}
      footer={<><Button variant="ghost" onClick={onClose}>취소</Button><Button onClick={save}>저장</Button></>}>
      <FormField label="제목"><Input value={title} onChange={setTitle} style={{ width: '100%' }} /></FormField>
      <FormField label="시작(yyyy-MM-ddTHH:mm:ss)"><Input value={startDt} onChange={setStartDt} style={{ width: '100%' }} /></FormField>
      <FormField label="종료"><Input value={endDt} onChange={setEndDt} style={{ width: '100%' }} /></FormField>
      <FormField label="내용"><Input value={content} onChange={setContent} style={{ width: '100%' }} /></FormField>
      {err && <div style={{ color: 'var(--uiws-danger)', fontSize: 13 }}>{err}</div>}
    </Modal>
  )
}

function ScheduleDetailModal({ detail, onClose, onDeleted }: { detail: any; onClose: () => void; onDeleted: () => void }) {
  const remove = async () => { await deleteSchedule(detail.scheduleId); onDeleted() }
  return (
    <Modal title={detail.title} onClose={onClose}
      footer={<><Button variant="danger" onClick={remove}>삭제</Button><Button variant="ghost" onClick={onClose}>닫기</Button></>}>
      <div style={{ fontSize: 13, color: 'var(--uiws-text-muted)', marginBottom: 8 }}>{detail.scheType} · {detail.startDt} ~ {detail.endDt}</div>
      <div style={{ fontSize: 14, color: 'var(--uiws-text)' }}>{detail.content || '내용 없음'}</div>
    </Modal>
  )
}
