'use client'
import { useState, useEffect, useMemo } from 'react'
import { ChevronLeft, ChevronRight, Plus, X, Clock, MapPin, Trash2, Eye, EyeOff, CalendarDays, User, AlignLeft, List } from 'lucide-react'

interface CalendarEvent {
  id: string
  title: string
  start: string
  end: string
  allDay: boolean
  description: string | null
  location: string | null
  owner: string
  ownerName: string
  color: string
}

const WEEKDAYS = ['Пн', 'Вт', 'Ср', 'Чт', 'Пт', 'Сб', 'Вс']
const MONTHS = ['Январь','Февраль','Март','Апрель','Май','Июнь','Июль','Август','Сентябрь','Октябрь','Ноябрь','Декабрь']

function formatTime(iso: string): string {
  return new Date(iso).toLocaleTimeString('ru-RU', { hour: '2-digit', minute: '2-digit' })
}

function formatFullDate(iso: string): string {
  return new Date(iso).toLocaleDateString('ru-RU', { weekday: 'long', day: 'numeric', month: 'long', year: 'numeric' })
}

// ————— Add Event Modal —————
const CALENDAR_OPTIONS = [
  { owner: 'daniil', name: 'Даниил', color: '#6366f1' },
  { owner: 'sveta', name: 'Света', color: '#ec4899' },
]

function AddEventModal({ defaultDate, onClose, onSaved }: { defaultDate: string; onClose: () => void; onSaved: (e: any) => void }) {
  const [title, setTitle] = useState('')
  const [date, setDate] = useState(defaultDate)
  const [startTime, setStartTime] = useState('10:00')
  const [endTime, setEndTime] = useState('11:00')
  const [allDay, setAllDay] = useState(false)
  const [owner, setOwner] = useState('daniil')
  const [saving, setSaving] = useState(false)
  const [error, setError] = useState('')

  const selectedCal = CALENDAR_OPTIONS.find(c => c.owner === owner) || CALENDAR_OPTIONS[0]

  const save = async () => {
    if (!title.trim()) { setError('Введите название'); return }
    setSaving(true); setError('')
    try {
      const body = { title: title.trim(), date, startTime: allDay ? null : startTime, endTime: allDay ? null : endTime, allDay, owner }
      const r = await fetch('/api/calendar', { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify(body) })
      const d = await r.json()
      if (d.error) throw new Error(d.error)
      onSaved(d.event)
    } catch (e: any) { setError(e.message || 'Ошибка сохранения'); setSaving(false) }
  }

  return (
    <div style={{
      position: 'fixed', inset: 0,
      background: 'rgba(0,0,0,0.6)', backdropFilter: 'blur(12px)',
      zIndex: 100, display: 'flex', alignItems: 'center', justifyContent: 'center',
      padding: 20,
    }} onClick={onClose}>
      <div style={{
        background: 'rgba(16,16,30,0.97)', backdropFilter: 'blur(40px)',
        border: '1px solid rgba(255,255,255,0.07)', borderRadius: 28,
        width: 420, maxWidth: '95vw', overflow: 'hidden',
        boxShadow: '0 30px 90px rgba(0,0,0,0.6)',
      }} onClick={e => e.stopPropagation()}>

        {/* Header */}
        <div style={{
          padding: '24px 28px 20px',
          borderBottom: '1px solid rgba(255,255,255,0.05)',
          display: 'flex', justifyContent: 'space-between', alignItems: 'center',
        }}>
          <span style={{ fontSize: 18, fontWeight: 700, color: 'var(--text-primary)' }}>
            Новое событие
          </span>
          <button onClick={onClose} style={{
            width: 32, height: 32, borderRadius: 10,
            background: 'rgba(255,255,255,0.05)',
            display: 'flex', alignItems: 'center', justifyContent: 'center',
            color: 'var(--text-secondary)',
          }}>
            <X size={16} />
          </button>
        </div>

        {/* Body */}
        <div style={{ padding: '20px 28px 28px' }}>

          {/* Calendar selector */}
          <div style={{ display: 'flex', gap: 8, marginBottom: 20 }}>
            {CALENDAR_OPTIONS.map(cal => {
              const sel = owner === cal.owner
              return (
                <button key={cal.owner} onClick={() => setOwner(cal.owner)} style={{
                  flex: 1, padding: '11px 0', borderRadius: 12,
                  background: sel ? `${cal.color}15` : 'rgba(255,255,255,0.03)',
                  border: `1.5px solid ${sel ? cal.color + '40' : 'rgba(255,255,255,0.06)'}`,
                  display: 'flex', alignItems: 'center', justifyContent: 'center', gap: 8,
                  transition: 'all 0.2s ease',
                }}>
                  <div style={{
                    width: 10, height: 10, borderRadius: '50%',
                    background: sel ? cal.color : 'rgba(255,255,255,0.15)',
                    boxShadow: sel ? `0 0 8px ${cal.color}50` : 'none',
                    transition: 'all 0.2s ease',
                  }} />
                  <span style={{
                    fontSize: 14, fontWeight: sel ? 600 : 400,
                    color: sel ? cal.color : 'var(--text-secondary)',
                  }}>{cal.name}</span>
                </button>
              )
            })}
          </div>

          {/* Title */}
          <input
            value={title} onChange={e => setTitle(e.target.value)}
            placeholder="Название события"
            autoFocus
            style={{
              width: '100%', padding: '15px 18px', borderRadius: 14,
              background: 'rgba(255,255,255,0.04)',
              border: '1px solid rgba(255,255,255,0.07)',
              color: 'var(--text-primary)', fontSize: 16, fontWeight: 500,
              outline: 'none', fontFamily: 'inherit',
              marginBottom: 16,
            }}
          />

          {/* Date */}
          <div style={{ marginBottom: 16 }}>
            <div style={{
              fontSize: 11, color: 'var(--text-secondary)', fontWeight: 600,
              textTransform: 'uppercase', letterSpacing: '0.08em',
              marginBottom: 8,
            }}>Дата</div>
            <input
              type="date" value={date} onChange={e => setDate(e.target.value)}
              style={{
                width: '100%', padding: '14px 18px', borderRadius: 14,
                background: 'rgba(255,255,255,0.04)',
                border: '1px solid rgba(255,255,255,0.07)',
                color: 'var(--text-primary)', fontSize: 15,
                outline: 'none', fontFamily: 'inherit',
              }}
            />
          </div>

          {/* All day toggle */}
          <button onClick={() => setAllDay(v => !v)} style={{
            width: '100%', padding: '13px 18px', borderRadius: 14,
            background: allDay ? `${selectedCal.color}10` : 'rgba(255,255,255,0.025)',
            border: `1px solid ${allDay ? selectedCal.color + '25' : 'rgba(255,255,255,0.06)'}`,
            display: 'flex', alignItems: 'center', justifyContent: 'space-between',
            marginBottom: 16, transition: 'all 0.2s ease',
          }}>
            <span style={{
              fontSize: 14, fontWeight: 500,
              color: allDay ? selectedCal.color : 'var(--text-secondary)',
            }}>Весь день</span>
            <div style={{
              width: 40, height: 22, borderRadius: 11,
              background: allDay ? selectedCal.color : 'rgba(255,255,255,0.1)',
              position: 'relative', transition: 'background 0.2s ease',
            }}>
              <div style={{
                width: 18, height: 18, borderRadius: '50%',
                background: '#fff', position: 'absolute', top: 2,
                left: allDay ? 20 : 2,
                transition: 'left 0.2s ease',
                boxShadow: '0 1px 3px rgba(0,0,0,0.3)',
              }} />
            </div>
          </button>

          {/* Time pickers */}
          {!allDay && (
            <div style={{ marginBottom: 16 }}>
              <div style={{
                fontSize: 11, color: 'var(--text-secondary)', fontWeight: 600,
                textTransform: 'uppercase', letterSpacing: '0.08em',
                marginBottom: 8,
              }}>Время</div>
              <div style={{
                display: 'flex', alignItems: 'center',
                background: 'rgba(255,255,255,0.04)',
                border: '1px solid rgba(255,255,255,0.07)',
                borderRadius: 14, overflow: 'hidden',
              }}>
                <input
                  type="time" value={startTime} onChange={e => setStartTime(e.target.value)}
                  style={{
                    flex: 1, padding: '14px 18px', border: 'none',
                    background: 'transparent', color: 'var(--text-primary)',
                    fontSize: 16, fontWeight: 600, fontFamily: 'inherit',
                    outline: 'none', textAlign: 'center',
                  }}
                />
                <div style={{
                  padding: '0 12px', color: 'var(--text-tertiary)',
                  fontSize: 13, fontWeight: 500, flexShrink: 0,
                  borderLeft: '1px solid rgba(255,255,255,0.06)',
                  borderRight: '1px solid rgba(255,255,255,0.06)',
                  height: '100%', display: 'flex', alignItems: 'center',
                  background: 'rgba(255,255,255,0.02)',
                }}>до</div>
                <input
                  type="time" value={endTime} onChange={e => setEndTime(e.target.value)}
                  style={{
                    flex: 1, padding: '14px 18px', border: 'none',
                    background: 'transparent', color: 'var(--text-primary)',
                    fontSize: 16, fontWeight: 600, fontFamily: 'inherit',
                    outline: 'none', textAlign: 'center',
                  }}
                />
              </div>
            </div>
          )}

          {/* Error */}
          {error && (
            <div style={{
              padding: '10px 14px', borderRadius: 12, marginBottom: 16,
              background: 'rgba(239,68,68,0.08)', border: '1px solid rgba(239,68,68,0.12)',
              color: '#f87171', fontSize: 13, fontWeight: 500,
            }}>{error}</div>
          )}

          {/* Submit */}
          <button onClick={save} disabled={saving} style={{
            width: '100%', padding: '15px', borderRadius: 14,
            background: saving
              ? 'rgba(255,255,255,0.04)'
              : `linear-gradient(135deg, ${selectedCal.color}45, ${selectedCal.color}30)`,
            border: `1px solid ${selectedCal.color}35`,
            color: selectedCal.color === '#ec4899' ? '#f9a8d4' : '#c7d2fe',
            fontSize: 15, fontWeight: 700,
            cursor: saving ? 'default' : 'pointer',
            transition: 'all 0.25s ease',
            boxShadow: saving ? 'none' : `0 4px 16px ${selectedCal.color}18`,
          }}>
            {saving ? 'Сохранение...' : 'Создать'}
          </button>
        </div>
      </div>
    </div>
  )
}

// ————— Event Detail Modal —————
function EventDetailModal({ event, onClose, onDelete, onUpdate }: {
  event: CalendarEvent
  onClose: () => void
  onDelete: (e: CalendarEvent) => Promise<void>
  onUpdate: (old: CalendarEvent, updated: Partial<CalendarEvent>) => Promise<void>
}) {
  const [confirmDelete, setConfirmDelete] = useState(false)
  const [deleting, setDeleting] = useState(false)
  const [editing, setEditing] = useState(false)
  const [editTitle, setEditTitle] = useState(event.title)
  const [editDate, setEditDate] = useState(
    event.start.includes('T') ? event.start.split('T')[0] : event.start
  )
  const [editStartTime, setEditStartTime] = useState(
    event.start.includes('T') ? formatTime(event.start) : '10:00'
  )
  const [editEndTime, setEditEndTime] = useState(
    event.end.includes('T') ? formatTime(event.end) : '11:00'
  )
  const [editAllDay, setEditAllDay] = useState(event.allDay)
  const [saving, setSaving] = useState(false)
  const [saveError, setSaveError] = useState('')

  const handleDelete = async () => {
    setDeleting(true)
    await onDelete(event)
    setDeleting(false)
  }

  const handleSave = async () => {
    if (!editTitle.trim()) { setSaveError('Введите название'); return }
    setSaving(true); setSaveError('')
    try {
      await onUpdate(event, {
        title: editTitle.trim(),
        start: editAllDay ? editDate : `${editDate}T${editStartTime}`,
        end: editAllDay ? editDate : `${editDate}T${editEndTime}`,
        allDay: editAllDay,
      })
    } catch (e: any) {
      setSaveError(e.message || 'Ошибка сохранения')
      setSaving(false)
    }
  }

  return (
    <div style={{ position: 'fixed', inset: 0, background: 'rgba(0,0,0,0.6)', backdropFilter: 'blur(12px)', zIndex: 100, display: 'flex', alignItems: 'center', justifyContent: 'center', padding: 20 }} onClick={onClose}>
      <div style={{
        background: 'rgba(16,16,30,0.97)', backdropFilter: 'blur(40px)',
        border: '1px solid rgba(255,255,255,0.07)', borderRadius: 28,
        width: 480, maxWidth: '95vw', overflow: 'hidden',
        boxShadow: '0 30px 90px rgba(0,0,0,0.6)',
      }} onClick={e => e.stopPropagation()}>

        {/* Colored header */}
        <div style={{
          background: `linear-gradient(135deg, ${event.color}20, ${event.color}08)`,
          borderBottom: `1px solid ${event.color}15`,
          padding: '24px 28px 20px',
        }}>
          <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'flex-start' }}>
            <div style={{ flex: 1, minWidth: 0 }}>
              {editing ? (
                <input
                  value={editTitle} onChange={e => setEditTitle(e.target.value)}
                  autoFocus
                  style={{
                    width: '100%', padding: '10px 14px', borderRadius: 12,
                    background: 'rgba(255,255,255,0.06)', border: '1px solid rgba(255,255,255,0.1)',
                    color: 'var(--text-primary)', fontSize: 18, fontWeight: 700,
                    outline: 'none', fontFamily: 'inherit',
                  }}
                />
              ) : (
                <div style={{ fontSize: 20, fontWeight: 700, color: 'var(--text-primary)', lineHeight: 1.3 }}>
                  {event.title}
                </div>
              )}
              <div style={{ display: 'flex', alignItems: 'center', gap: 8, marginTop: 8 }}>
                <div style={{ width: 8, height: 8, borderRadius: '50%', background: event.color, boxShadow: `0 0 8px ${event.color}60` }} />
                <span style={{ fontSize: 13, color: event.color, fontWeight: 600 }}>{event.ownerName}</span>
              </div>
            </div>
            <div style={{ display: 'flex', gap: 6, marginLeft: 12, flexShrink: 0 }}>
              {!editing && (
                <button onClick={() => setEditing(true)} style={{
                  padding: '8px 14px', borderRadius: 10,
                  background: 'rgba(255,255,255,0.06)',
                  color: 'var(--text-secondary)', fontSize: 12, fontWeight: 600,
                }}>
                  Изменить
                </button>
              )}
              <button onClick={onClose} style={{
                width: 32, height: 32, borderRadius: 10,
                background: 'rgba(255,255,255,0.06)',
                display: 'flex', alignItems: 'center', justifyContent: 'center',
                color: 'var(--text-secondary)',
              }}>
                <X size={16} />
              </button>
            </div>
          </div>
        </div>

        {/* Content */}
        <div style={{ padding: '20px 28px 24px', display: 'flex', flexDirection: 'column', gap: 14 }}>

          {editing ? (
            <>
              {/* Date */}
              <div>
                <div style={{ fontSize: 11, color: 'var(--text-secondary)', fontWeight: 600, textTransform: 'uppercase', letterSpacing: '0.08em', marginBottom: 8 }}>Дата</div>
                <input type="date" value={editDate} onChange={e => setEditDate(e.target.value)} style={{
                  width: '100%', padding: '12px 16px', borderRadius: 12,
                  background: 'rgba(255,255,255,0.04)', border: '1px solid rgba(255,255,255,0.07)',
                  color: 'var(--text-primary)', fontSize: 15, outline: 'none', fontFamily: 'inherit',
                }} />
              </div>

              {/* All day toggle */}
              <button onClick={() => setEditAllDay(v => !v)} style={{
                width: '100%', padding: '12px 16px', borderRadius: 12,
                background: editAllDay ? `${event.color}10` : 'rgba(255,255,255,0.025)',
                border: `1px solid ${editAllDay ? event.color + '25' : 'rgba(255,255,255,0.06)'}`,
                display: 'flex', alignItems: 'center', justifyContent: 'space-between',
              }}>
                <span style={{ fontSize: 14, fontWeight: 500, color: editAllDay ? event.color : 'var(--text-secondary)' }}>Весь день</span>
                <div style={{
                  width: 40, height: 22, borderRadius: 11,
                  background: editAllDay ? event.color : 'rgba(255,255,255,0.1)',
                  position: 'relative', transition: 'background 0.2s ease',
                }}>
                  <div style={{
                    width: 18, height: 18, borderRadius: '50%', background: '#fff',
                    position: 'absolute', top: 2, left: editAllDay ? 20 : 2,
                    transition: 'left 0.2s ease', boxShadow: '0 1px 3px rgba(0,0,0,0.3)',
                  }} />
                </div>
              </button>

              {/* Time */}
              {!editAllDay && (
                <div>
                  <div style={{ fontSize: 11, color: 'var(--text-secondary)', fontWeight: 600, textTransform: 'uppercase', letterSpacing: '0.08em', marginBottom: 8 }}>Время</div>
                  <div style={{
                    display: 'flex', alignItems: 'center',
                    background: 'rgba(255,255,255,0.04)', border: '1px solid rgba(255,255,255,0.07)',
                    borderRadius: 12, overflow: 'hidden',
                  }}>
                    <input type="time" value={editStartTime} onChange={e => setEditStartTime(e.target.value)} style={{
                      flex: 1, padding: '12px 16px', border: 'none', background: 'transparent',
                      color: 'var(--text-primary)', fontSize: 16, fontWeight: 600,
                      fontFamily: 'inherit', outline: 'none', textAlign: 'center',
                    }} />
                    <div style={{
                      padding: '0 10px', color: 'var(--text-tertiary)', fontSize: 12,
                      borderLeft: '1px solid rgba(255,255,255,0.06)',
                      borderRight: '1px solid rgba(255,255,255,0.06)',
                      background: 'rgba(255,255,255,0.02)',
                      height: '100%', display: 'flex', alignItems: 'center',
                    }}>до</div>
                    <input type="time" value={editEndTime} onChange={e => setEditEndTime(e.target.value)} style={{
                      flex: 1, padding: '12px 16px', border: 'none', background: 'transparent',
                      color: 'var(--text-primary)', fontSize: 16, fontWeight: 600,
                      fontFamily: 'inherit', outline: 'none', textAlign: 'center',
                    }} />
                  </div>
                </div>
              )}

              {saveError && (
                <div style={{ color: '#f87171', fontSize: 13, padding: '8px 12px', borderRadius: 10, background: 'rgba(239,68,68,0.08)' }}>{saveError}</div>
              )}

              {/* Save / Cancel */}
              <div style={{ display: 'flex', gap: 8, marginTop: 4 }}>
                <button onClick={handleSave} disabled={saving} style={{
                  flex: 1, padding: '13px', borderRadius: 14,
                  background: `linear-gradient(135deg, ${event.color}45, ${event.color}30)`,
                  border: `1px solid ${event.color}35`,
                  color: '#c7d2fe', fontSize: 14, fontWeight: 700,
                }}>
                  {saving ? 'Сохранение...' : 'Сохранить'}
                </button>
                <button onClick={() => { setEditing(false); setEditTitle(event.title) }} style={{
                  padding: '13px 20px', borderRadius: 14,
                  background: 'rgba(255,255,255,0.04)', border: '1px solid rgba(255,255,255,0.08)',
                  color: 'var(--text-secondary)', fontSize: 14, fontWeight: 600,
                }}>
                  Отмена
                </button>
              </div>
            </>
          ) : (
            <>
              {/* View mode */}
              <div style={{
                display: 'flex', alignItems: 'center', gap: 14,
                padding: '14px 16px', borderRadius: 14,
                background: 'rgba(255,255,255,0.03)', border: '1px solid rgba(255,255,255,0.05)',
              }}>
                <CalendarDays size={18} color={event.color} />
                <div>
                  <div style={{ fontSize: 14, fontWeight: 600, color: 'var(--text-primary)', textTransform: 'capitalize' }}>
                    {formatFullDate(event.start)}
                  </div>
                  <div style={{ fontSize: 13, color: 'var(--text-secondary)', marginTop: 3 }}>
                    {event.allDay ? 'Весь день' : `${formatTime(event.start)} — ${formatTime(event.end)}`}
                  </div>
                </div>
              </div>

              {event.location && (
                <div style={{
                  display: 'flex', alignItems: 'center', gap: 14,
                  padding: '14px 16px', borderRadius: 14,
                  background: 'rgba(255,255,255,0.03)', border: '1px solid rgba(255,255,255,0.05)',
                }}>
                  <MapPin size={18} color="#fb923c" />
                  <div style={{ fontSize: 14, color: 'var(--text-primary)', fontWeight: 500 }}>{event.location}</div>
                </div>
              )}

              {event.description && (
                <div style={{
                  padding: '14px 16px', borderRadius: 14,
                  background: 'rgba(255,255,255,0.03)', border: '1px solid rgba(255,255,255,0.05)',
                }}>
                  <div style={{ display: 'flex', alignItems: 'center', gap: 8, marginBottom: 8 }}>
                    <AlignLeft size={14} color="var(--text-secondary)" />
                    <span style={{ fontSize: 11, color: 'var(--text-secondary)', fontWeight: 600, textTransform: 'uppercase', letterSpacing: '0.05em' }}>Описание</span>
                  </div>
                  <div style={{ fontSize: 14, color: 'var(--text-primary)', lineHeight: 1.7, whiteSpace: 'pre-wrap' }}>{event.description}</div>
                </div>
              )}

              {/* Delete */}
              <div style={{ borderTop: '1px solid rgba(255,255,255,0.05)', paddingTop: 14, marginTop: 4 }}>
                {!confirmDelete ? (
                  <button onClick={() => setConfirmDelete(true)} style={{
                    display: 'flex', alignItems: 'center', justifyContent: 'center', gap: 8,
                    padding: '12px', borderRadius: 14, width: '100%',
                    background: 'rgba(239,68,68,0.06)', border: '1px solid rgba(239,68,68,0.15)',
                    color: '#f87171', fontSize: 13, fontWeight: 600,
                  }}>
                    <Trash2 size={15} /> Удалить
                  </button>
                ) : (
                  <div style={{ display: 'flex', gap: 8 }}>
                    <button onClick={handleDelete} disabled={deleting} style={{
                      flex: 1, padding: '12px', borderRadius: 14,
                      background: deleting ? 'rgba(239,68,68,0.06)' : 'rgba(239,68,68,0.12)',
                      border: '1px solid rgba(239,68,68,0.25)',
                      color: '#f87171', fontSize: 13, fontWeight: 600,
                    }}>
                      {deleting ? 'Удаление...' : 'Да, удалить'}
                    </button>
                    <button onClick={() => setConfirmDelete(false)} style={{
                      flex: 1, padding: '12px', borderRadius: 14,
                      background: 'rgba(255,255,255,0.04)', border: '1px solid rgba(255,255,255,0.08)',
                      color: 'var(--text-secondary)', fontSize: 13, fontWeight: 600,
                    }}>
                      Отмена
                    </button>
                  </div>
                )}
              </div>
            </>
          )}
        </div>
      </div>
    </div>
  )
}


// ————— Day Events Popover —————
function DayEventsModal({ day, month, year, events, onClose, onSelect }: {
  day: number; month: number; year: number
  events: CalendarEvent[]
  onClose: () => void
  onSelect: (e: CalendarEvent) => void
}) {
  const date = new Date(year, month, day)
  const label = date.toLocaleDateString('ru-RU', { weekday: 'long', day: 'numeric', month: 'long' })

  return (
    <div style={{ position: 'fixed', inset: 0, background: 'rgba(0,0,0,0.5)', backdropFilter: 'blur(8px)', zIndex: 100, display: 'flex', alignItems: 'center', justifyContent: 'center', padding: 20 }} onClick={onClose}>
      <div style={{
        background: 'rgba(18,18,35,0.95)', backdropFilter: 'blur(40px)',
        border: '1px solid rgba(255,255,255,0.08)', borderRadius: 24,
        padding: '24px 28px', width: 400, maxWidth: '95vw',
        boxShadow: '0 25px 60px rgba(0,0,0,0.5)',
      }} onClick={e => e.stopPropagation()}>
        <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: 20 }}>
          <span style={{ fontSize: 17, fontWeight: 700, color: 'var(--text-primary)', textTransform: 'capitalize' }}>{label}</span>
          <button onClick={onClose} style={{ color: 'var(--text-secondary)', padding: 4 }}><X size={18} /></button>
        </div>
        <div style={{ display: 'flex', flexDirection: 'column', gap: 8 }}>
          {events.map(e => (
            <button key={e.id} onClick={() => onSelect(e)} style={{
              display: 'flex', alignItems: 'center', gap: 12,
              padding: '14px 16px', borderRadius: 14, width: '100%', textAlign: 'left',
              background: `${e.color}0c`, border: `1px solid ${e.color}20`,
              transition: 'all 0.2s ease',
            }}>
              <div style={{ width: 4, borderRadius: 2, background: e.color, alignSelf: 'stretch', minHeight: 36, flexShrink: 0 }} />
              <div style={{ flex: 1, minWidth: 0 }}>
                <div style={{ fontSize: 14, fontWeight: 600, color: 'var(--text-primary)', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>{e.title}</div>
                <div style={{ fontSize: 12, color: 'var(--text-secondary)', marginTop: 3, display: 'flex', gap: 8 }}>
                  <span>{e.allDay ? 'Весь день' : `${formatTime(e.start)} — ${formatTime(e.end)}`}</span>
                  <span style={{ color: e.color, fontWeight: 500 }}>{e.ownerName}</span>
                </div>
              </div>
            </button>
          ))}
        </div>
      </div>
    </div>
  )
}

// ————— Main Calendar —————
export default function CalendarTab() {
  const [year, setYear] = useState(new Date().getFullYear())
  const [month, setMonth] = useState(new Date().getMonth())
  const [events, setEvents] = useState<CalendarEvent[]>([])
  const [loading, setLoading] = useState(true)
  const [selectedEvent, setSelectedEvent] = useState<CalendarEvent | null>(null)
  const [showAddModal, setShowAddModal] = useState(false)
  const [addDate, setAddDate] = useState<string>('')
  const [hiddenOwners, setHiddenOwners] = useState<Set<string>>(new Set())
  const [dayPopover, setDayPopover] = useState<{ day: number; events: CalendarEvent[] } | null>(null)
  const [showUpcoming, setShowUpcoming] = useState(false)

  useEffect(() => {
    setLoading(true)
    fetch('/api/calendar?range=month&year=' + year + '&month=' + month)
      .then(r => r.json())
      .then(d => { setEvents(d.events || []); setLoading(false) })
      .catch(() => setLoading(false))
  }, [year, month])

  const deleteEvent = async (event: CalendarEvent) => {
    try {
      const r = await fetch(`/api/calendar?eventId=${event.id}`, { method: 'DELETE' })
      const d = await r.json()
      if (d.error) throw new Error(d.error)
      setEvents(prev => prev.filter(e => e.id !== event.id))
      setSelectedEvent(null)
    } catch (e: any) { alert(e.message || 'Ошибка удаления') }
  }

  const calendarOwners = useMemo(() => {
    const map = new Map<string, { owner: string; ownerName: string; color: string; count: number }>()
    events.forEach(e => {
      const existing = map.get(e.owner)
      if (existing) existing.count++
      else map.set(e.owner, { owner: e.owner, ownerName: e.ownerName, color: e.color, count: 1 })
    })
    return Array.from(map.values())
  }, [events])

  const toggleOwner = (owner: string) => {
    setHiddenOwners(prev => {
      const next = new Set(prev)
      if (next.has(owner)) next.delete(owner)
      else next.add(owner)
      return next
    })
  }

  const filteredEvents = useMemo(() => {
    if (hiddenOwners.size === 0) return events
    return events.filter(e => !hiddenOwners.has(e.owner))
  }, [events, hiddenOwners])

  const upcoming = filteredEvents
    .filter(e => new Date(e.start) >= new Date())
    .slice(0, 6)

  const firstDay = new Date(year, month, 1)
  const lastDay = new Date(year, month + 1, 0)
  const startOffset = (firstDay.getDay() + 6) % 7
  const totalCells = Math.ceil((startOffset + lastDay.getDate()) / 7) * 7
  const cells: (number | null)[] = []
  for (let i = 0; i < totalCells; i++) {
    const dayNum = i - startOffset + 1
    cells.push(dayNum >= 1 && dayNum <= lastDay.getDate() ? dayNum : null)
  }

  const getEventsForDay = (day: number) => {
    return filteredEvents.filter(e => {
      const d = new Date(e.start)
      return d.getFullYear() === year && d.getMonth() === month && d.getDate() === day
    })
  }

  const prevMonth = () => { if (month === 0) { setMonth(11); setYear(y => y - 1) } else setMonth(m => m - 1) }
  const nextMonth = () => { if (month === 11) { setMonth(0); setYear(y => y + 1) } else setMonth(m => m + 1) }
  const today = new Date()

  const handleDayClick = (day: number) => {
    const dayEvents = getEventsForDay(day)
    if (dayEvents.length === 0) {
      setAddDate(`${year}-${String(month + 1).padStart(2, '0')}-${String(day).padStart(2, '0')}`)
      setShowAddModal(true)
    } else if (dayEvents.length === 1) {
      setSelectedEvent(dayEvents[0])
    } else {
      setDayPopover({ day, events: dayEvents })
    }
  }

  return (
    <div style={{ flex: 1, display: 'flex', overflow: 'hidden', padding: '16px 24px 24px', position: 'relative' }}>
      {/* Main calendar grid */}
      <div style={{ flex: 1, display: 'flex', flexDirection: 'column', minWidth: 0 }}>
        {/* Header */}
        <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'space-between', marginBottom: 14 }}>
          <div style={{ display: 'flex', alignItems: 'center', gap: 12 }}>
            <button onClick={prevMonth} style={{ width: 36, height: 36, borderRadius: 12, background: 'rgba(255,255,255,0.04)', border: '1px solid rgba(255,255,255,0.06)', color: 'var(--text-primary)', display: 'flex', alignItems: 'center', justifyContent: 'center' }}>
              <ChevronLeft size={16} />
            </button>
            <span style={{ fontSize: 20, fontWeight: 700, color: 'var(--text-primary)', minWidth: 180, textAlign: 'center' }}>
              {MONTHS[month]} {year}
            </span>
            <button onClick={nextMonth} style={{ width: 36, height: 36, borderRadius: 12, background: 'rgba(255,255,255,0.04)', border: '1px solid rgba(255,255,255,0.06)', color: 'var(--text-primary)', display: 'flex', alignItems: 'center', justifyContent: 'center' }}>
              <ChevronRight size={16} />
            </button>
          </div>

          <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
            {calendarOwners.map(cal => {
              const isHidden = hiddenOwners.has(cal.owner)
              return (
                <button key={cal.owner} onClick={() => toggleOwner(cal.owner)} style={{
                  display: 'flex', alignItems: 'center', gap: 6,
                  padding: '7px 14px', borderRadius: 12,
                  background: isHidden ? 'rgba(255,255,255,0.02)' : `${cal.color}15`,
                  border: `1px solid ${isHidden ? 'rgba(255,255,255,0.06)' : cal.color + '30'}`,
                  color: isHidden ? 'var(--text-tertiary)' : cal.color,
                  fontSize: 12, fontWeight: 600, transition: 'all 0.25s ease',
                  opacity: isHidden ? 0.5 : 1,
                }}>
                  {isHidden ? <EyeOff size={13} /> : <Eye size={13} />}
                  {cal.ownerName}
                  <span style={{ fontSize: 10, padding: '1px 6px', borderRadius: 6, background: isHidden ? 'rgba(255,255,255,0.05)' : `${cal.color}20` }}>
                    {cal.count}
                  </span>
                </button>
              )
            })}
            <button onClick={() => setShowUpcoming(v => !v)} style={{
              width: 36, height: 36, borderRadius: 12,
              background: showUpcoming ? 'rgba(99,102,241,0.15)' : 'rgba(255,255,255,0.04)',
              border: showUpcoming ? '1px solid rgba(129,140,248,0.25)' : '1px solid rgba(255,255,255,0.06)',
              color: showUpcoming ? '#a5b4fc' : 'var(--text-secondary)',
              display: 'flex', alignItems: 'center', justifyContent: 'center',
              transition: 'all 0.25s ease',
            }}>
              <List size={16} />
            </button>
            <button onClick={() => { setAddDate(today.toISOString().split('T')[0]); setShowAddModal(true) }} style={{
              display: 'flex', alignItems: 'center', gap: 6,
              padding: '8px 18px', borderRadius: 14,
              background: 'linear-gradient(135deg, rgba(99,102,241,0.2), rgba(139,92,246,0.15))',
              border: '1px solid rgba(129,140,248,0.25)',
              color: '#a5b4fc', fontSize: 13, fontWeight: 600,
            }}>
              <Plus size={15} /> Событие
            </button>
          </div>
        </div>

        {/* Weekday headers */}
        <div style={{ display: 'grid', gridTemplateColumns: 'repeat(7, 1fr)', marginBottom: 4 }}>
          {WEEKDAYS.map((d, i) => (
            <div key={d} style={{
              textAlign: 'center', fontSize: 11, fontWeight: 600,
              color: i >= 5 ? 'rgba(248,113,113,0.5)' : 'var(--text-secondary)',
              textTransform: 'uppercase', padding: '6px 0', letterSpacing: '0.05em',
            }}>{d}</div>
          ))}
        </div>

        {/* Calendar cells */}
        <div style={{ display: 'grid', gridTemplateColumns: 'repeat(7, 1fr)', flex: 1, gap: 3 }}>
          {cells.map((day, idx) => {
            if (!day) return <div key={idx} />
            const dayEvents = getEventsForDay(day)
            const isToday = today.getFullYear() === year && today.getMonth() === month && today.getDate() === day
            const dayOfWeek = (startOffset + day - 1) % 7
            const isWeekend = dayOfWeek >= 5
            return (
              <div
                key={idx}
                onClick={() => handleDayClick(day)}
                style={{
                  borderRadius: 12, padding: '4px 5px',
                  background: isToday ? 'linear-gradient(135deg, rgba(99,102,241,0.15), rgba(139,92,246,0.08))' : 'rgba(255,255,255,0.015)',
                  border: isToday ? '1px solid rgba(129,140,248,0.3)' : '1px solid transparent',
                  cursor: 'pointer', minHeight: 70,
                  display: 'flex', flexDirection: 'column', gap: 3,
                  transition: 'all 0.2s ease',
                }}
              >
                <span style={{
                  fontSize: 12, fontWeight: isToday ? 700 : 500,
                  color: isToday ? '#a5b4fc' : isWeekend ? 'rgba(248,113,113,0.6)' : 'var(--text-secondary)',
                  textAlign: 'right', paddingRight: 3, lineHeight: 1,
                }}>{day}</span>
                {dayEvents.slice(0, 3).map(e => (
                  <div
                    key={e.id}
                    onClick={ev => { ev.stopPropagation(); setSelectedEvent(e) }}
                    style={{
                      display: 'flex', alignItems: 'center', gap: 4,
                      background: `${e.color}18`,
                      borderLeft: `3px solid ${e.color}`,
                      borderRadius: '0 6px 6px 0',
                      padding: '4px 6px',
                      cursor: 'pointer',
                      overflow: 'hidden',
                    }}
                  >
                    {!e.allDay && (
                      <span style={{ fontSize: 9, color: `${e.color}cc`, fontWeight: 600, flexShrink: 0, fontVariantNumeric: 'tabular-nums' }}>
                        {formatTime(e.start)}
                      </span>
                    )}
                    <span style={{
                      fontSize: 11, fontWeight: 600, color: e.color,
                      overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap',
                    }}>
                      {e.title}
                    </span>
                  </div>
                ))}
                {dayEvents.length > 3 && (
                  <div style={{ fontSize: 10, color: 'var(--text-secondary)', textAlign: 'center', fontWeight: 500 }}>
                    +{dayEvents.length - 3}
                  </div>
                )}
              </div>
            )
          })}
        </div>
      </div>

      {/* Right panel — overlay */}
      {showUpcoming && <div style={{ position: 'fixed', inset: 0, zIndex: 90 }} onClick={() => setShowUpcoming(false)} />}
      <div style={{
        position: 'absolute', top: 16, right: 24, bottom: 24,
        width: 240, display: 'flex', flexDirection: 'column', gap: 10,
        overflowY: 'auto',
        background: 'rgba(18,18,35,0.95)', backdropFilter: 'blur(30px)', WebkitBackdropFilter: 'blur(30px)',
        borderRadius: 22, padding: '20px 16px',
        border: '1px solid rgba(255,255,255,0.08)',
        boxShadow: '0 16px 48px rgba(0,0,0,0.4)',
        transform: showUpcoming ? 'translateX(0)' : 'translateX(calc(100% + 24px))',
        transition: 'transform 0.3s cubic-bezier(0.4, 0, 0.2, 1)',
        zIndex: 95, pointerEvents: showUpcoming ? 'auto' : 'none',
      }}>
        <div style={{ fontSize: 11, fontWeight: 600, color: 'var(--text-secondary)', textTransform: 'uppercase', letterSpacing: '0.1em', marginBottom: 4 }}>Ближайшие</div>
        {upcoming.length === 0 && !loading && (
          <div style={{ fontSize: 13, color: 'var(--text-secondary)', padding: '20px 0', textAlign: 'center' }}>Нет событий</div>
        )}
        {upcoming.map(e => {
          const d = new Date(e.start)
          return (
            <div key={e.id} onClick={() => setSelectedEvent(e)} style={{
              borderRadius: 16, padding: '14px',
              background: `${e.color}0c`, border: `1px solid ${e.color}1a`,
              cursor: 'pointer', transition: 'all 0.25s ease',
            }}>
              <div style={{ display: 'flex', alignItems: 'center', gap: 8, marginBottom: 8 }}>
                <div style={{ width: 34, height: 34, borderRadius: 10, background: `${e.color}1a`, display: 'flex', alignItems: 'center', justifyContent: 'center', flexShrink: 0 }}>
                  <span style={{ fontSize: 15, fontWeight: 700, color: e.color }}>{d.getDate()}</span>
                </div>
                <div>
                  <div style={{ fontSize: 10, color: e.color, fontWeight: 600 }}>{MONTHS[d.getMonth()].slice(0, 3)}</div>
                  <div style={{ fontSize: 10, color: 'var(--text-secondary)' }}>
                    {e.allDay ? 'Весь день' : formatTime(e.start)}
                  </div>
                </div>
              </div>
              <div style={{ fontSize: 13, fontWeight: 600, color: 'var(--text-primary)', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>{e.title}</div>
              <div style={{ fontSize: 10, color: e.color, marginTop: 6, fontWeight: 500 }}>{e.ownerName}</div>
            </div>
          )
        })}
      </div>

      {/* Modals */}
      {selectedEvent && (
        <EventDetailModal event={selectedEvent} onClose={() => setSelectedEvent(null)} onDelete={deleteEvent} onUpdate={updateEvent} />
      )}

      {dayPopover && (
        <DayEventsModal
          day={dayPopover.day} month={month} year={year} events={dayPopover.events}
          onClose={() => setDayPopover(null)}
          onSelect={e => { setDayPopover(null); setSelectedEvent(e) }}
        />
      )}

      {showAddModal && (
        <AddEventModal
          defaultDate={addDate}
          onClose={() => setShowAddModal(false)}
          onSaved={(newEvent) => { setEvents(prev => [...prev, newEvent]); setShowAddModal(false) }}
        />
      )}
    </div>
  )
}