'use client'

import { useState, useEffect, useCallback } from 'react'
import ProtectedRoute from '@/components/ProtectedRoute'
import Modal from '@/components/Modal'
import LoadingSpinner from '@/components/LoadingSpinner'
import Link from 'next/link'
import { toast } from 'react-hot-toast'
import {
  FileText,
  Plus,
  Search,
  Calendar,
  Building2,
  DollarSign,
  AlertCircle,
  ArrowLeft,
  Eye,
  Loader2,
} from 'lucide-react'
import { tendersAPI, Tender, CreateTenderData, TenderFilters } from '@/lib/api/tenders'
import { useLanguage } from '@/contexts/LanguageContext'

const SOURCE_LABELS: Record<string, string> = {
  GOVERNMENT_SITE: 'Government site',
  OFFICIAL_GAZETTE: 'Official gazette',
  PERSONAL: 'Personal relations',
  PARTNER: 'Partner companies',
  WHATSAPP_TELEGRAM: 'WhatsApp/Telegram',
  PORTAL: 'Tender portals',
  EMAIL: 'Email',
  MANUAL: 'Manual entry',
}

const ANNOUNCEMENT_LABELS: Record<string, string> = {
  FIRST: 'First announcement',
  RE_ANNOUNCEMENT_2: 'Re-announcement 2nd',
  RE_ANNOUNCEMENT_3: 'Re-announcement 3rd',
  RE_ANNOUNCEMENT_4: 'Re-announcement 4th',
}

function TendersContent() {
  const { t } = useLanguage()
  const [tenders, setTenders] = useState<Tender[]>([])
  const [loading, setLoading] = useState(true)
  const [currentPage, setCurrentPage] = useState(1)
  const [totalPages, setTotalPages] = useState(1)
  const [total, setTotal] = useState(0)
  const pageSize = 10
  const [searchTerm, setSearchTerm] = useState('')
  const [selectedStatus, setSelectedStatus] = useState('all')
  const [showCreateModal, setShowCreateModal] = useState(false)
  const [formData, setFormData] = useState<CreateTenderData>({
    tenderNumber: '',
    issuingBodyName: '',
    title: '',
    termsValue: 0,
    bondValue: 0,
    announcementDate: '',
    closingDate: '',
    source: 'MANUAL',
    announcementType: 'FIRST',
  })
  const [formErrors, setFormErrors] = useState<Record<string, string>>({})
  const [submitting, setSubmitting] = useState(false)
  const [possibleDuplicates, setPossibleDuplicates] = useState<Tender[]>([])
  const [showDuplicateWarning, setShowDuplicateWarning] = useState(false)
  const [sourceValues, setSourceValues] = useState<string[]>([])
  const [announcementTypeValues, setAnnouncementTypeValues] = useState<string[]>([])

  const fetchTenders = useCallback(async () => {
    setLoading(true)
    try {
      const filters: TenderFilters = { page: currentPage, pageSize }
      if (searchTerm) filters.search = searchTerm
      if (selectedStatus !== 'all') filters.status = selectedStatus
      const data = await tendersAPI.getAll(filters)
      setTenders(data.tenders)
      setTotal(data.total)
      setTotalPages(data.totalPages)
    } catch {
      toast.error(t('tenders.loadError') || 'Failed to load tenders')
    } finally {
      setLoading(false)
    }
  }, [currentPage, searchTerm, selectedStatus, t])

  useEffect(() => {
    fetchTenders()
  }, [fetchTenders])

  useEffect(() => {
    tendersAPI.getSourceValues().then(setSourceValues).catch(() => {})
    tendersAPI.getAnnouncementTypeValues().then(setAnnouncementTypeValues).catch(() => {})
  }, [])

  const handleCreate = async (e: React.FormEvent) => {
    e.preventDefault()
    const errors: Record<string, string> = {}
    if (!formData.tenderNumber?.trim()) errors.tenderNumber = t('common.required')
    if (!formData.issuingBodyName?.trim()) errors.issuingBodyName = t('common.required')
    if (!formData.title?.trim()) errors.title = t('common.required')
    if (!formData.announcementDate) errors.announcementDate = t('common.required')
    if (!formData.closingDate) errors.closingDate = t('common.required')
    //if (Number(formData.termsValue) < 0) errors.termsValue = t('common.required')
    if (Number(formData.bondValue) < 0) errors.bondValue = t('common.required')
    setFormErrors(errors)
    if (Object.keys(errors).length > 0) return

    setSubmitting(true)
    try {
      const result = await tendersAPI.create(formData)
      if (result.possibleDuplicates && result.possibleDuplicates.length > 0) {
        setPossibleDuplicates(result.possibleDuplicates)
        setShowDuplicateWarning(true)
        toast(t('tenders.duplicateWarning') || 'Possible duplicates found. Please review.', { icon: '⚠️' })
      } else {
        toast.success(t('tenders.createSuccess') || 'Tender created successfully')
        setShowCreateModal(false)
        resetForm()
        fetchTenders()
      }
    } catch (err: any) {
      toast.error(err.response?.data?.message || 'Failed to create tender')
    } finally {
      setSubmitting(false)
    }
  }

  const resetForm = () => {
    setFormData({
      tenderNumber: '',
      issuingBodyName: '',
      title: '',
      termsValue: 0,
      bondValue: 0,
      announcementDate: '',
      closingDate: '',
      source: 'MANUAL',
      announcementType: 'FIRST',
    })
    setFormErrors({})
    setPossibleDuplicates([])
    setShowDuplicateWarning(false)
  }

  return (
    <div className="min-h-screen bg-gray-50">
      <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
        <div className="mb-6 flex items-center justify-between">
          <div className="flex items-center gap-3">
            <Link
              href="/dashboard"
              className="p-2 hover:bg-gray-200 rounded-lg transition-colors"
            >
              <ArrowLeft className="h-5 w-5" />
            </Link>
            <div className="flex items-center gap-2">
              <FileText className="h-8 w-8 text-indigo-600" />
              <div>
                <h1 className="text-2xl font-bold text-gray-900">{t('nav.tenders') || 'Tenders'}</h1>
                <p className="text-sm text-gray-600">{t('tenders.subtitle') || 'Tender Management'}</p>
              </div>
            </div>
          </div>
          <button
            onClick={() => { setShowCreateModal(true); resetForm(); }}
            className="flex items-center gap-2 px-4 py-2 bg-indigo-600 text-white rounded-lg hover:bg-indigo-700"
          >
            <Plus className="h-5 w-5" />
            {t('tenders.addTender') || 'Add Tender'}
          </button>
        </div>

        <div className="bg-white rounded-xl shadow-sm border border-gray-200 overflow-hidden">
          <div className="p-4 border-b border-gray-200 flex flex-wrap gap-4 items-center">
            <div className="relative flex-1 min-w-[200px]">
              <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-4 w-4 text-gray-400" />
              <input
                type="text"
                placeholder={t('tenders.searchPlaceholder') || 'Search by number, title, issuing body...'}
                value={searchTerm}
                onChange={(e) => setSearchTerm(e.target.value)}
                className="w-full pl-10 pr-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-indigo-500 focus:border-indigo-500"
              />
            </div>
            <select
              value={selectedStatus}
              onChange={(e) => setSelectedStatus(e.target.value)}
              className="px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-indigo-500"
            >
              <option value="all">{t('common.all') || 'All status'}</option>
              <option value="ACTIVE">Active</option>
              <option value="CONVERTED_TO_DEAL">Converted</option>
              <option value="CANCELLED">Cancelled</option>
            </select>
          </div>

          {loading ? (
            <div className="flex justify-center py-12">
              <LoadingSpinner />
            </div>
          ) : tenders.length === 0 ? (
            <div className="text-center py-12 text-gray-500">
              {t('tenders.noTenders') || 'No tenders found.'}
            </div>
          ) : (
            <div className="overflow-x-auto">
              <table className="min-w-full divide-y divide-gray-200">
                <thead className="bg-gray-50">
                  <tr>
                    <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase">{t('tenders.tenderNumber') || 'Number'}</th>
                    <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase">{t('tenders.title') || 'Title'}</th>
                    <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase">{t('tenders.issuingBody') || 'Issuing body'}</th>
                    <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase">{t('tenders.closingDate') || 'Closing date'}</th>
                    <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase">{t('common.status')}</th>
                    <th className="px-4 py-3 text-right text-xs font-medium text-gray-500 uppercase">{t('common.actions')}</th>
                  </tr>
                </thead>
                <tbody className="bg-white divide-y divide-gray-200">
                  {tenders.map((tender) => (
                    <tr key={tender.id} className="hover:bg-gray-50">
                      <td className="px-4 py-3 text-sm font-medium text-gray-900">{tender.tenderNumber}</td>
                      <td className="px-4 py-3 text-sm text-gray-900">{tender.title}</td>
                      <td className="px-4 py-3 text-sm text-gray-600">{tender.issuingBodyName}</td>
                      <td className="px-4 py-3 text-sm text-gray-600">{tender.closingDate?.split('T')[0]}</td>
                      <td className="px-4 py-3">
                        <span className={`px-2 py-1 text-xs rounded-full ${
                          tender.status === 'ACTIVE' ? 'bg-green-100 text-green-800' :
                          tender.status === 'CONVERTED_TO_DEAL' ? 'bg-blue-100 text-blue-800' : 'bg-gray-100 text-gray-800'
                        }`}>
                          {tender.status}
                        </span>
                      </td>
                      <td className="px-4 py-3 text-right">
                        <Link
                          href={`/tenders/${tender.id}`}
                          className="inline-flex items-center gap-1 text-indigo-600 hover:underline"
                        >
                          <Eye className="h-4 w-4" />
                          {t('common.view') || 'View'}
                        </Link>
                      </td>
                    </tr>
                  ))}
                </tbody>
              </table>
            </div>
          )}

          {totalPages > 1 && (
            <div className="px-4 py-3 border-t border-gray-200 flex items-center justify-between">
              <p className="text-sm text-gray-600">
                {t('common.showing') || 'Showing'} {(currentPage - 1) * pageSize + 1}–{Math.min(currentPage * pageSize, total)} {t('common.of') || 'of'} {total}
              </p>
              <div className="flex gap-2">
                <button
                  disabled={currentPage <= 1}
                  onClick={() => setCurrentPage((p) => p - 1)}
                  className="px-3 py-1 border rounded disabled:opacity-50"
                >
                  {t('crm.paginationPrevious') || 'Previous'}
                </button>
                <button
                  disabled={currentPage >= totalPages}
                  onClick={() => setCurrentPage((p) => p + 1)}
                  className="px-3 py-1 border rounded disabled:opacity-50"
                >
                  {t('crm.paginationNext') || 'Next'}
                </button>
              </div>
            </div>
          )}
        </div>
      </div>

      <Modal
        isOpen={showCreateModal}
        onClose={() => { setShowCreateModal(false); setShowDuplicateWarning(false); resetForm(); }}
        title={t('tenders.addTender') || 'Add Tender'}
      >
        <form onSubmit={handleCreate} className="space-y-4">
          <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.tenderNumber')} *</label>
              <input
                type="text"
                value={formData.tenderNumber}
                onChange={(e) => setFormData({ ...formData, tenderNumber: e.target.value })}
                className="w-full px-3 py-2 border rounded-lg"
              />
              {formErrors.tenderNumber && <p className="text-red-500 text-xs mt-1">{formErrors.tenderNumber}</p>}
            </div>
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.issuingBody')} *</label>
              <input
                type="text"
                value={formData.issuingBodyName}
                onChange={(e) => setFormData({ ...formData, issuingBodyName: e.target.value })}
                className="w-full px-3 py-2 border rounded-lg"
              />
              {formErrors.issuingBodyName && <p className="text-red-500 text-xs mt-1">{formErrors.issuingBodyName}</p>}
            </div>
          </div>
          <div>
            <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.titleLabel')} *</label>
            <input
              type="text"
              value={formData.title}
              onChange={(e) => setFormData({ ...formData, title: e.target.value })}
              className="w-full px-3 py-2 border rounded-lg"
            />
            {formErrors.title && <p className="text-red-500 text-xs mt-1">{formErrors.title}</p>}
          </div>
          <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.termsValue')} *</label>
              <input
                type="number"
                value={formData.termsValue || ''}
                onChange={(e) => setFormData({ ...formData, termsValue: Number(e.target.value) || 0 })}
                className="w-full px-3 py-2 border rounded-lg"
              />
            </div>
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.bondValue')} *</label>
              <input
                type="number"
                min={0}
                value={formData.bondValue || ''}
                onChange={(e) => setFormData({ ...formData, bondValue: Number(e.target.value) || 0 })}
                className="w-full px-3 py-2 border rounded-lg"
              />
            </div>
          </div>
          <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.announcementDate')} *</label>
              <input
                type="date"
                value={formData.announcementDate}
                onChange={(e) => setFormData({ ...formData, announcementDate: e.target.value })}
                className="w-full px-3 py-2 border rounded-lg"
              />
              {formErrors.announcementDate && <p className="text-red-500 text-xs mt-1">{formErrors.announcementDate}</p>}
            </div>
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.closingDate')} *</label>
              <input
                type="date"
                value={formData.closingDate}
                onChange={(e) => setFormData({ ...formData, closingDate: e.target.value })}
                className="w-full px-3 py-2 border rounded-lg"
              />
              {formErrors.closingDate && <p className="text-red-500 text-xs mt-1">{formErrors.closingDate}</p>}
            </div>
          </div>
          <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.source')}</label>
              <select
                value={formData.source}
                onChange={(e) => setFormData({ ...formData, source: e.target.value })}
                className="w-full px-3 py-2 border rounded-lg"
              >
                {sourceValues.map((s) => (
                  <option key={s} value={s}>{SOURCE_LABELS[s] || s}</option>
                ))}
              </select>
            </div>
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.announcementType')}</label>
              <select
                value={formData.announcementType}
                onChange={(e) => setFormData({ ...formData, announcementType: e.target.value })}
                className="w-full px-3 py-2 border rounded-lg"
              >
                {announcementTypeValues.map((a) => (
                  <option key={a} value={a}>{ANNOUNCEMENT_LABELS[a] || a}</option>
                ))}
              </select>
            </div>
          </div>
          <div>
            <label className="block text-sm font-medium text-gray-700 mb-1">{t('tenders.announcementLink')}</label>
            <input
              type="url"
              value={formData.announcementLink || ''}
              onChange={(e) => setFormData({ ...formData, announcementLink: e.target.value })}
              className="w-full px-3 py-2 border rounded-lg"
            />
          </div>
          <div>
            <label className="block text-sm font-medium text-gray-700 mb-1">{t('common.notes')}</label>
            <textarea
              value={formData.notes || ''}
              onChange={(e) => setFormData({ ...formData, notes: e.target.value })}
              className="w-full px-3 py-2 border rounded-lg"
              rows={2}
            />
          </div>
          {showDuplicateWarning && possibleDuplicates.length > 0 && (
            <div className="p-3 bg-amber-50 border border-amber-200 rounded-lg flex items-start gap-2">
              <AlertCircle className="h-5 w-5 text-amber-600 flex-shrink-0 mt-0.5" />
              <div>
                <p className="text-sm font-medium text-amber-800">{t('tenders.duplicateWarning') || 'Possible duplicates found'}</p>
                <ul className="text-sm text-amber-700 mt-1 list-disc list-inside">
                  {possibleDuplicates.slice(0, 3).map((d) => (
                    <li key={d.id}>
                      <Link href={`/tenders/${d.id}`} className="underline">{d.tenderNumber} - {d.title}</Link>
                    </li>
                  ))}
                </ul>
              </div>
            </div>
          )}
          <div className="flex justify-end gap-2 pt-4">
            <button
              type="button"
              onClick={() => { setShowCreateModal(false); resetForm(); }}
              className="px-4 py-2 border rounded-lg"
            >
              {t('common.cancel')}
            </button>
            <button
              type="submit"
              disabled={submitting}
              className="px-4 py-2 bg-indigo-600 text-white rounded-lg hover:bg-indigo-700 disabled:opacity-50 flex items-center gap-2"
            >
              {submitting && <Loader2 className="h-4 w-4 animate-spin" />}
              {t('common.save')}
            </button>
          </div>
        </form>
      </Modal>
    </div>
  )
}

export default function TendersPage() {
  return (
    <ProtectedRoute>
      <TendersContent />
    </ProtectedRoute>
  )
}