'use client';

import { useState } from 'react';
import { useQuery } from '@tanstack/react-query';
import Link from 'next/link';
import api from '@/lib/api';
import { useAuthStore } from '@/lib/store';
import type { Ticket, TicketStatus } from '@/types';
import { Wrench, Briefcase, User, CheckCircle } from 'lucide-react';

const statusColors: Record<string, string> = {
  open: 'bg-yellow-100 text-yellow-700',
  waiting: 'bg-orange-100 text-orange-700',
  answered: 'bg-green-100 text-green-700',
  closed: 'bg-gray-100 text-gray-500',
};

const priorityColors: Record<string, string> = {
  low: 'bg-blue-100 text-blue-700',
  medium: 'bg-yellow-100 text-yellow-700',
  high: 'bg-red-100 text-red-700',
};

export default function StaffTicketsPage() {
  const user = useAuthStore((s) => s.user);
  const [statusFilter, setStatusFilter] = useState<TicketStatus | ''>('');

  // Determine which department this staff member handles
  const department = user?.role === 'sales' ? 'sales' : 'technical';
  const departmentLabel = department === 'technical' ? 'Technical' : 'Sales';
  const DeptIcon = department === 'technical' ? Wrench : Briefcase;

  const { data: tickets = [], isLoading } = useQuery<Ticket[]>({
    queryKey: ['staff-tickets', department, statusFilter],
    queryFn: () => {
      const params = statusFilter ? `?status=${statusFilter}` : '';
      return api.get(`/tickets/staff/${department}${params}`).then((r) => r.data);
    },
  });

  const unansweredCount = tickets.filter((t) => t.status === 'open' || t.status === 'waiting').length;
  const answeredCount = tickets.filter((t) => t.status === 'answered').length;

  return (
    <div className="space-y-6">
      <div>
        <h1 className="text-2xl font-bold text-gray-900 flex items-center gap-2"><DeptIcon className="w-5 h-5" /> {departmentLabel} Tickets</h1>
        <p className="text-sm text-gray-500 mt-1">
          {tickets.length} total tickets
        </p>
      </div>

      {/* Summary Cards */}
      <div className="grid grid-cols-3 gap-4">
        <div className="card p-4">
          <p className="text-xs text-gray-500 uppercase font-semibold">Unanswered</p>
          <p className={`text-2xl font-bold mt-1 ${unansweredCount > 0 ? 'text-red-600' : 'text-green-600'}`}>
            {unansweredCount}
          </p>
          <p className="text-xs text-gray-400 mt-0.5">Need response</p>
        </div>
        <div className="card p-4">
          <p className="text-xs text-gray-500 uppercase font-semibold">Answered</p>
          <p className="text-2xl font-bold text-green-600 mt-1">{answeredCount}</p>
          <p className="text-xs text-gray-400 mt-0.5">Waiting for user</p>
        </div>
        <div className="card p-4">
          <p className="text-xs text-gray-500 uppercase font-semibold">Total Open</p>
          <p className="text-2xl font-bold text-gray-900 mt-1">
            {tickets.filter((t) => t.status !== 'closed').length}
          </p>
          <p className="text-xs text-gray-400 mt-0.5">Excluding closed</p>
        </div>
      </div>

      {/* Filters */}
      <div className="flex flex-wrap gap-2">
        {(['', 'open', 'waiting', 'answered', 'closed'] as const).map((status) => (
          <button
            key={status}
            onClick={() => setStatusFilter(status)}
            className={`px-3 py-1.5 rounded-lg text-sm font-medium transition-colors ${
              statusFilter === status
                ? 'bg-primary-500 text-white'
                : 'bg-gray-100 text-gray-600 hover:bg-gray-200'
            }`}
          >
            {status === '' ? 'All' : status.charAt(0).toUpperCase() + status.slice(1)}
          </button>
        ))}
      </div>

      {/* Tickets List */}
      {isLoading ? (
        <div className="text-center py-12">
          <div className="animate-spin rounded-full h-8 w-8 border-2 border-primary-600 border-t-transparent mx-auto" />
        </div>
      ) : tickets.length === 0 ? (
        <div className="card p-12 text-center">
          <CheckCircle className="w-10 h-10 mx-auto text-gray-300" />
          <h3 className="mt-3 text-lg font-semibold text-gray-700">No tickets</h3>
          <p className="text-sm text-gray-500 mt-1">
            {statusFilter ? `No ${statusFilter} tickets` : 'No tickets in this department'}
          </p>
        </div>
      ) : (
        <div className="space-y-3">
          {tickets.map((ticket) => (
            <Link
              key={ticket.id}
              href={`/dashboard/tickets/${ticket.id}`}
              className="card p-4 block hover:shadow-md transition-shadow"
            >
              <div className="flex items-start justify-between gap-3">
                <div className="flex-1 min-w-0">
                  <div className="flex items-center gap-2 flex-wrap">
                    <h3 className="font-semibold text-gray-900 truncate">{ticket.subject}</h3>
                    <span className={`px-2 py-0.5 rounded-full text-xs font-medium ${statusColors[ticket.status]}`}>
                      {ticket.status}
                    </span>
                    <span className={`px-2 py-0.5 rounded-full text-xs font-medium ${priorityColors[ticket.priority]}`}>
                      {ticket.priority}
                    </span>
                  </div>
                  <div className="flex items-center gap-3 mt-1.5 text-xs text-gray-500">
                    {ticket.user && (
                      <span className="flex items-center gap-1">
                        <User className="w-3 h-3" /> {ticket.user.firstName} {ticket.user.lastName} ({ticket.user.email})
                      </span>
                    )}
                    <span>•</span>
                    <span>{new Date(ticket.createdAt).toLocaleDateString('en-US', { month: 'short', day: 'numeric', hour: '2-digit', minute: '2-digit' })}</span>
                    <span>•</span>
                    <span>{ticket.messages?.length || 0} msg{(ticket.messages?.length || 0) !== 1 ? 's' : ''}</span>
                  </div>
                </div>
                <span className="text-gray-400 text-sm">→</span>
              </div>
            </Link>
          ))}
        </div>
      )}
    </div>
  );
}