import { useState } from 'react'
import { useAlert } from '../context/AlertContext'
import { useAuth } from '../context/AuthContext'
import { Link } from 'react-router-dom'
import Forbidden from '../components/Forbidden'
import { motion } from 'framer-motion'
import ConfirmModal from '../components/ConfirmModal'

import apiFetch from '../utils/api'
import { formatCurrency, formatDate, czechPlural } from '../utils/formatters'
import SortIcon from '../components/SortIcon'
import useTableSort from '../hooks/useTableSort'
import useListData from '../hooks/useListData'
import Pagination from '../components/Pagination'

const API_BASE = '/api/admin'

const STATUS_LABELS: Record<string, string> = {
  prijata: 'Přijatá',
  v_realizaci: 'V realizaci',
  dokoncena: 'Dokončená',
  stornovana: 'Stornována'
}

const STATUS_CLASSES: Record<string, string> = {
  prijata: 'admin-badge-order-prijata',
  v_realizaci: 'admin-badge-order-realizace',
  dokoncena: 'admin-badge-order-dokoncena',
  stornovana: 'admin-badge-order-stornovana'
}

interface Order {
  id: number
  order_number: string
  quotation_id: number
  quotation_number: string
  customer_name: string
  status: string
  created_at: string
  total: number
  currency: string
  invoice_id?: number
}

export default function Orders() {
  const alert = useAlert()
  const { hasPermission } = useAuth()

  const { sort, order, handleSort, activeSort } = useTableSort('order_number')
  const [search, setSearch] = useState('')
  const [page, setPage] = useState(1)

  const [deleteConfirm, setDeleteConfirm] = useState<{ show: boolean; order: Order | null }>({ show: false, order: null })
  const [deleting, setDeleting] = useState(false)
  const [deleteFiles, setDeleteFiles] = useState(false)

  const { items: orders, loading, initialLoad, pagination, refetch: fetchData } = useListData('orders', {
    search, sort, order, page,
    errorMsg: 'Nepodařilo se načíst objednávky'
  })

  if (!hasPermission('orders.view')) return <Forbidden />

  const handleDelete = async () => {
    if (!deleteConfirm.order) return
    setDeleting(true)
    try {
      const response = await apiFetch(`${API_BASE}/orders/${deleteConfirm.order.id}`, {
        method: 'DELETE',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ delete_files: deleteFiles }),
      })
      const result = await response.json()
      if (result.success) {
        setDeleteConfirm({ show: false, order: null })
        setDeleteFiles(false)
        alert.success(result.message || 'Objednávka byla smazána')
        fetchData()
      } else {
        alert.error(result.error || 'Nepodařilo se smazat objednávku')
      }
    } catch {
      alert.error('Chyba připojení')
    } finally {
      setDeleting(false)
    }
  }

  if (initialLoad) {
    return (
      <div>
        <div className="admin-skeleton" style={{ padding: 0, gap: '1.5rem' }}>
          <div className="admin-skeleton-row" style={{ justifyContent: 'space-between' }}>
            <div>
              <div className="admin-skeleton-line h-8" style={{ width: '200px', marginBottom: '0.5rem' }} />
              <div className="admin-skeleton-line" style={{ width: '140px' }} />
            </div>
            <div className="admin-skeleton-line h-10" style={{ width: '140px', borderRadius: '8px' }} />
          </div>
          <div className="admin-card">
            <div className="admin-skeleton" style={{ gap: '1.25rem' }}>
              {[0, 1, 2, 3, 4].map(i => (
                <div key={i} className="admin-skeleton-row">
                  <div className="admin-skeleton-line circle" />
                  <div className="flex-1">
                    <div className="admin-skeleton-line w-1/3" style={{ marginBottom: '0.5rem' }} />
                    <div className="admin-skeleton-line w-1/4" style={{ height: '10px' }} />
                  </div>
                  <div className="admin-skeleton-line w-1/4" />
                </div>
              ))}
            </div>
          </div>
        </div>
      </div>
    )
  }

  return (
    <div>
      <motion.div
        className="admin-page-header"
        initial={{ opacity: 0, y: 12 }}
        animate={{ opacity: 1, y: 0 }}
        transition={{ duration: 0.25 }}
      >
        <div>
          <h1 className="admin-page-title">Objednávky</h1>
          <p className="admin-page-subtitle">
            {pagination?.total ?? orders.length} {czechPlural(pagination?.total ?? orders.length, 'objednávka', 'objednávky', 'objednávek')}
          </p>
        </div>
      </motion.div>

      <motion.div
        className="admin-card"
        initial={{ opacity: 0, y: 12 }}
        animate={{ opacity: 1, y: 0 }}
        transition={{ duration: 0.25, delay: 0.06 }}
        style={{ opacity: loading ? 0.6 : 1, transition: 'opacity 0.2s', pointerEvents: loading ? 'none' : 'auto' }}
      >
        <div className="admin-card-body">
          <div className="admin-search-bar mb-4">
            <input
              type="text"
              value={search}
              onChange={(e) => { setSearch(e.target.value); setPage(1) }}
              className="admin-form-input"
              placeholder="Hledat podle čísla, nabídky, projektu nebo zákazníka..."
            />
          </div>

          {orders.length === 0 ? (
            <div className="admin-empty-state">
              <div className="admin-empty-icon">
                <svg width="28" height="28" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round">
                  <path d="M6 2L3 6v14a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2V6l-3-4z" />
                  <line x1="3" y1="6" x2="21" y2="6" />
                  <path d="M16 10a4 4 0 0 1-8 0" />
                </svg>
              </div>
              <p>Zatím nejsou žádné objednávky.</p>
              <p className="text-tertiary" style={{ fontSize: '0.875rem' }}>
                Objednávky se vytvářejí z nabídek.
              </p>
            </div>
          ) : (
            <div className="admin-table-responsive">
              <table className="admin-table">
                <thead>
                  <tr>
                    <th style={{ cursor: 'pointer' }} onClick={() => handleSort('order_number')}>
                      Číslo <SortIcon column="order_number" sort={activeSort} order={order} />
                    </th>
                    <th>Nabídka</th>
                    <th>Zákazník</th>
                    <th style={{ cursor: 'pointer' }} onClick={() => handleSort('status')}>
                      Stav <SortIcon column="status" sort={activeSort} order={order} />
                    </th>
                    <th style={{ cursor: 'pointer' }} onClick={() => handleSort('created_at')}>
                      Datum <SortIcon column="created_at" sort={activeSort} order={order} />
                    </th>
                    <th className="text-right">Celkem</th>
                    <th>Akce</th>
                  </tr>
                </thead>
                <tbody>
                  {(orders as Order[]).map((o) => (
                    <tr key={o.id}>
                      <td className="admin-mono">
                        <Link to={`/orders/${o.id}`} className="link-accent">
                          {o.order_number}
                        </Link>
                      </td>
                      <td>
                        <Link to={`/offers/${o.quotation_id}`} className="text-secondary" style={{ textDecoration: 'none' }}>
                          {o.quotation_number}
                        </Link>
                      </td>
                      <td>{o.customer_name || '—'}</td>
                      <td>
                        <span className={`admin-badge ${STATUS_CLASSES[o.status] || ''}`}>
                          {STATUS_LABELS[o.status] || o.status}
                        </span>
                      </td>
                      <td className="admin-mono">
                        {formatDate(o.created_at)}
                      </td>
                      <td className="admin-mono text-right fw-500">
                        {formatCurrency(o.total, o.currency)}
                      </td>
                      <td>
                        <div className="admin-table-actions">
                          <Link to={`/orders/${o.id}`} className="admin-btn-icon" title="Detail" aria-label="Detail">
                            <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                              <path d="M1 12s4-8 11-8 11 8 11 8-4 8-11 8-11-8-11-8z" />
                              <circle cx="12" cy="12" r="3" />
                            </svg>
                          </Link>
                          {o.invoice_id ? (
                            <Link to={`/invoices/${o.invoice_id}`} className="admin-btn-icon accent" title="Zobrazit fakturu" aria-label="Zobrazit fakturu">
                              <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                                <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z" />
                                <polyline points="14 2 14 8 20 8" />
                                <text x="12" y="16.5" textAnchor="middle" fill="currentColor" stroke="none" fontSize="9" fontWeight="700">F</text>
                              </svg>
                            </Link>
                          ) : hasPermission('invoices.create') && (
                            <Link to={`/invoices/new?fromOrder=${o.id}`} className="admin-btn-icon" title="Vytvořit fakturu" aria-label="Vytvořit fakturu">
                              <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                                <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z" />
                                <polyline points="14 2 14 8 20 8" />
                                <line x1="12" y1="11" x2="12" y2="17" />
                                <line x1="9" y1="14" x2="15" y2="14" />
                              </svg>
                            </Link>
                          )}
                          {hasPermission('orders.delete') && (
                            <button
                              onClick={() => setDeleteConfirm({ show: true, order: o })}
                              className="admin-btn-icon danger"
                              title="Smazat"
                            >
                              <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                                <polyline points="3 6 5 6 21 6" />
                                <path d="M19 6v14a2 2 0 0 1-2 2H7a2 2 0 0 1-2-2V6m3 0V4a2 2 0 0 1 2-2h4a2 2 0 0 1 2 2v2" />
                              </svg>
                            </button>
                          )}
                        </div>
                      </td>
                    </tr>
                  ))}
                </tbody>
              </table>
            </div>
          )}
          <Pagination pagination={pagination} onPageChange={setPage} />
        </div>
      </motion.div>

      <ConfirmModal
        isOpen={deleteConfirm.show}
        onClose={() => {
          setDeleteConfirm({ show: false, order: null })
          setDeleteFiles(false)
        }}
        onConfirm={handleDelete}
        title="Smazat objednávku"
        message={
          <>
            Opravdu chcete smazat objednávku &quot;{deleteConfirm.order?.order_number}&quot;? Bude smazán i přidružený projekt. Tato akce je nevratná.
            <label className="admin-form-checkbox" style={{ marginTop: '1rem', display: 'flex' }}>
              <input
                type="checkbox"
                checked={deleteFiles}
                onChange={(e) => setDeleteFiles(e.target.checked)}
              />
              <span>Smazat i soubory projektu na disku</span>
            </label>
          </>
        }
        confirmText="Smazat"
        cancelText="Zrušit"
        type="danger"
        loading={deleting}
      />
    </div>
  )
}