import { useState } from 'react'
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
import toast from 'react-hot-toast'
import client from '../api/client'

const TYPE_LABELS = {
  supplier: 'Προμηθευτής',
  staff:    'Προσωπικό',
  utility:  'Κοινή Χρεία',
  other:    'Άλλο',
}
const TYPE_COLORS = {
  supplier: { bg: '#eff6ff', color: '#1d4ed8' },
  staff:    { bg: '#f0fdf4', color: '#15803d' },
  utility:  { bg: '#fefce8', color: '#a16207' },
  other:    { bg: '#f3f4f6', color: '#374151' },
}

const EMPTY_FORM = { name: '', type: 'supplier', phone: '', email: '', address: '', notes: '' }

function ContactModal({ initial, onClose, onSave, isPending }) {
  const [form, setForm] = useState(initial ?? EMPTY_FORM)
  const f = (k, v) => setForm(p => ({ ...p, [k]: v }))
  const isNew = !initial?.id
  const canSave = form.name.trim()

  const inputStyle = {
    width: '100%', padding: '8px 11px', border: '1px solid #e5e7eb',
    borderRadius: 8, fontSize: 13.5, outline: 'none', fontFamily: 'inherit',
    background: 'white',
  }

  return (
    <div style={{
      position: 'fixed', inset: 0, background: 'rgba(0,0,0,0.45)',
      display: 'flex', alignItems: 'center', justifyContent: 'center',
      zIndex: 50, padding: 20,
    }}>
      <div style={{
        background: 'white', borderRadius: 16, width: '100%', maxWidth: 520,
        boxShadow: '0 20px 60px rgba(0,0,0,0.18)', display: 'flex', flexDirection: 'column',
      }}>
        <div style={{ padding: '18px 22px 14px', borderBottom: '1px solid #f0f0ef', display: 'flex', justifyContent: 'space-between', alignItems: 'center' }}>
          <h2 style={{ margin: 0, fontSize: 16, fontWeight: 700 }}>{isNew ? 'Νέα Επαφή' : 'Επεξεργασία Επαφής'}</h2>
          <button onClick={onClose} style={{ background: 'none', border: 'none', fontSize: 18, cursor: 'pointer', color: '#9ca3af' }}>✕</button>
        </div>

        <div style={{ padding: '18px 22px', display: 'flex', flexDirection: 'column', gap: 14 }}>
          <div>
            <label style={{ fontSize: 12, fontWeight: 600, color: '#374151', display: 'block', marginBottom: 5 }}>Όνομα *</label>
            <input style={inputStyle} value={form.name} onChange={e => f('name', e.target.value)} autoFocus placeholder="π.χ. Νίκος Γαλακτοπωλείο" />
          </div>
          <div>
            <label style={{ fontSize: 12, fontWeight: 600, color: '#374151', display: 'block', marginBottom: 5 }}>Τύπος</label>
            <select style={inputStyle} value={form.type} onChange={e => f('type', e.target.value)}>
              {Object.entries(TYPE_LABELS).map(([k, v]) => <option key={k} value={k}>{v}</option>)}
            </select>
          </div>
          <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: 12 }}>
            <div>
              <label style={{ fontSize: 12, fontWeight: 600, color: '#374151', display: 'block', marginBottom: 5 }}>Τηλέφωνο</label>
              <input style={inputStyle} value={form.phone} onChange={e => f('phone', e.target.value)} placeholder="π.χ. 6912345678" />
            </div>
            <div>
              <label style={{ fontSize: 12, fontWeight: 600, color: '#374151', display: 'block', marginBottom: 5 }}>Email</label>
              <input style={inputStyle} type="email" value={form.email} onChange={e => f('email', e.target.value)} placeholder="info@example.com" />
            </div>
          </div>
          <div>
            <label style={{ fontSize: 12, fontWeight: 600, color: '#374151', display: 'block', marginBottom: 5 }}>Διεύθυνση</label>
            <input style={inputStyle} value={form.address} onChange={e => f('address', e.target.value)} placeholder="Οδός, Πόλη" />
          </div>
          <div>
            <label style={{ fontSize: 12, fontWeight: 600, color: '#374151', display: 'block', marginBottom: 5 }}>Σημειώσεις</label>
            <textarea style={{ ...inputStyle, resize: 'none' }} rows={3} value={form.notes} onChange={e => f('notes', e.target.value)} placeholder="Εσωτερικές σημειώσεις…" />
          </div>
        </div>

        <div style={{ padding: '14px 22px', borderTop: '1px solid #f0f0ef', display: 'flex', justifyContent: 'flex-end', gap: 10 }}>
          <button onClick={onClose} style={{ padding: '8px 18px', border: '1px solid #e5e7eb', background: 'white', borderRadius: 8, fontSize: 13, cursor: 'pointer' }}>Ακύρωση</button>
          <button
            onClick={() => onSave(form)}
            disabled={!canSave || isPending}
            style={{
              padding: '8px 20px', border: 'none', borderRadius: 8, fontSize: 13, fontWeight: 600,
              cursor: canSave && !isPending ? 'pointer' : 'default',
              background: canSave ? '#111827' : '#e5e7eb',
              color: canSave ? 'white' : '#9ca3af',
            }}
          >
            {isPending ? 'Αποθήκευση…' : isNew ? 'Δημιουργία' : 'Αποθήκευση'}
          </button>
        </div>
      </div>
    </div>
  )
}

export default function ContactsPage() {
  const qc = useQueryClient()
  const [modal, setModal] = useState(null) // null | { contact } | { contact: null } for new

  const { data: contacts = [], isLoading } = useQuery({
    queryKey: ['contacts'],
    queryFn: () => client.get('/api/contacts/').then(r => r.data),
    staleTime: 30_000,
  })

  const save = useMutation({
    mutationFn: ({ form, id }) => id
      ? client.put(`/api/contacts/${id}`, form)
      : client.post('/api/contacts/', form),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: ['contacts'] })
      setModal(null)
      toast.success('Αποθηκεύτηκε')
    },
    onError: () => toast.error('Σφάλμα αποθήκευσης'),
  })

  const deactivate = useMutation({
    mutationFn: (id) => client.delete(`/api/contacts/${id}`),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: ['contacts'] })
      toast.success('Η επαφή αποενεργοποιήθηκε')
    },
    onError: () => toast.error('Σφάλμα'),
  })

  return (
    <div style={{ display: 'flex', flexDirection: 'column', height: '100%', overflow: 'hidden' }}>
      {/* Header */}
      <div style={{ padding: '18px 28px 14px', borderBottom: '1px solid #f0f0ef', display: 'flex', alignItems: 'center', justifyContent: 'space-between', flexShrink: 0, background: 'white' }}>
        <div>
          <p style={{ margin: 0, fontSize: 13, color: '#9ca3af' }}>{contacts.length} ενεργές επαφές</p>
        </div>
        <button
          onClick={() => setModal({ contact: null })}
          style={{ padding: '9px 18px', borderRadius: 9, border: 'none', background: '#111827', color: 'white', fontSize: 13, fontWeight: 600, cursor: 'pointer' }}
        >
          + Νέα Επαφή
        </button>
      </div>

      {/* Table */}
      <div style={{ flex: 1, overflowY: 'auto', padding: '20px 28px' }}>
        {isLoading && <div style={{ textAlign: 'center', color: '#9ca3af', padding: '48px 0' }}>Φόρτωση…</div>}
        {!isLoading && contacts.length === 0 && (
          <div style={{ textAlign: 'center', color: '#9ca3af', padding: '48px 0', fontSize: 14 }}>
            Δεν υπάρχουν επαφές ακόμα. Προσθέστε τον πρώτο προμηθευτή.
          </div>
        )}
        {contacts.length > 0 && (
          <div style={{ border: '1px solid #e5e7eb', borderRadius: 12, overflow: 'hidden' }}>
            <table style={{ width: '100%', borderCollapse: 'collapse', fontSize: 13.5 }}>
              <thead>
                <tr style={{ background: '#f9fafb', borderBottom: '1px solid #e5e7eb' }}>
                  {['Όνομα', 'Τύπος', 'Τηλέφωνο', 'Email', ''].map(h => (
                    <th key={h} style={{ padding: '10px 16px', textAlign: 'left', fontSize: 11, fontWeight: 700, color: '#9ca3af', textTransform: 'uppercase', letterSpacing: '0.05em', whiteSpace: 'nowrap' }}>{h}</th>
                  ))}
                </tr>
              </thead>
              <tbody>
                {contacts.map((c, i) => {
                  const tc = TYPE_COLORS[c.type] || TYPE_COLORS.other
                  return (
                    <tr key={c.id} style={{ borderBottom: i < contacts.length - 1 ? '1px solid #f3f4f6' : 'none', background: 'white' }}>
                      <td style={{ padding: '12px 16px', fontWeight: 600, color: '#111315' }}>
                        {c.name}
                        {c.notes && <div style={{ fontSize: 11.5, color: '#9ca3af', fontWeight: 400, marginTop: 1 }}>{c.notes.slice(0, 60)}{c.notes.length > 60 ? '…' : ''}</div>}
                      </td>
                      <td style={{ padding: '12px 16px' }}>
                        <span style={{ fontSize: 11.5, fontWeight: 700, padding: '2px 8px', borderRadius: 99, background: tc.bg, color: tc.color }}>
                          {TYPE_LABELS[c.type] || c.type}
                        </span>
                      </td>
                      <td style={{ padding: '12px 16px', color: c.phone ? '#374151' : '#d1d5db' }}>{c.phone || '—'}</td>
                      <td style={{ padding: '12px 16px', color: c.email ? '#374151' : '#d1d5db' }}>{c.email || '—'}</td>
                      <td style={{ padding: '12px 16px', textAlign: 'right' }}>
                        <div style={{ display: 'flex', gap: 6, justifyContent: 'flex-end' }}>
                          <button
                            onClick={() => setModal({ contact: c })}
                            style={{ padding: '4px 12px', borderRadius: 6, border: '1px solid #e5e7eb', background: 'white', fontSize: 12, fontWeight: 500, cursor: 'pointer', color: '#374151' }}
                          >
                            Επεξεργασία
                          </button>
                          <button
                            onClick={() => { if (window.confirm(`Αποενεργοποίηση "${c.name}";`)) deactivate.mutate(c.id) }}
                            style={{ padding: '4px 10px', borderRadius: 6, border: '1px solid #fecaca', background: 'white', fontSize: 12, cursor: 'pointer', color: '#ef4444' }}
                          >
                            Απενεργ.
                          </button>
                        </div>
                      </td>
                    </tr>
                  )
                })}
              </tbody>
            </table>
          </div>
        )}
      </div>

      {modal && (
        <ContactModal
          initial={modal.contact ? { ...modal.contact, phone: modal.contact.phone || '', email: modal.contact.email || '', address: modal.contact.address || '', notes: modal.contact.notes || '' } : null}
          onClose={() => setModal(null)}
          isPending={save.isPending}
          onSave={(form) => save.mutate({
            form: { name: form.name, type: form.type, phone: form.phone || null, email: form.email || null, address: form.address || null, notes: form.notes || null },
            id: modal.contact?.id,
          })}
        />
      )}
    </div>
  )
}
