'use client';

import { useState } from 'react';
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import Link from 'next/link';
import api from '@/lib/api';
import { useAuthStore } from '@/lib/store';
import { toast } from 'react-toastify';
import type { Ticket, CreateTicketDto, TicketDepartment, TicketPriority } from '@/types';
import { Wrench, Briefcase, Ticket as TicketIcon, X } 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 TicketsPage() {
  const queryClient = useQueryClient();
  const user = useAuthStore((s) => s.user);
  const [showCreate, setShowCreate] = useState(false);

  // Staff can only create tickets to other departments
  const availableDepartments: { value: TicketDepartment; label: string }[] = [];
  if (user?.role !== 'technical') {
    availableDepartments.push({ value: 'technical', label: 'Technical Support' });
  }
  if (user?.role !== 'sales') {
    availableDepartments.push({ value: 'sales', label: 'Sales' });
  }
  const canCreateTicket = availableDepartments.length > 0;
  const [form, setForm] = useState<CreateTicketDto>({
    subject: '',
    department: availableDepartments[0]?.value || 'technical',
    priority: 'medium',
    message: '',
  });

  const { data: tickets = [], isLoading } = useQuery<Ticket[]>({
    queryKey: ['my-tickets'],
    queryFn: () => api.get('/tickets/my').then((r) => r.data),
  });

  const createMutation = useMutation({
    mutationFn: (data: CreateTicketDto) => api.post('/tickets', data).then((r) => r.data),
    onSuccess: () => {
      toast.success('Ticket created successfully');
      queryClient.invalidateQueries({ queryKey: ['my-tickets'] });
      setShowCreate(false);
      setForm({ subject: '', department: availableDepartments[0]?.value || 'technical', priority: 'medium', message: '' });
    },
    onError: (err: any) => toast.error(err.response?.data?.message || 'Failed to create ticket'),
  });

  const handleSubmit = (e: React.FormEvent) => {
    e.preventDefault();
    createMutation.mutate(form);
  };

  return (
    <div className="space-y-6">
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-bold text-gray-900">My Tickets</h1>
          <p className="text-sm text-gray-500 mt-1">Support tickets and their status</p>
        </div>
        {canCreateTicket && (
          <button onClick={() => setShowCreate(!showCreate)} className="btn-primary">
            {showCreate ? <><X className="w-4 h-4 inline" /> Cancel</> : '+ New Ticket'}
          </button>
        )}
      </div>

      {/* Create Ticket Form */}
      {showCreate && canCreateTicket && (
        <form onSubmit={handleSubmit} className="card p-6 space-y-4">
          <h2 className="text-lg font-semibold text-gray-900">Create New Ticket</h2>

          <div>
            <label className="block text-sm font-medium text-gray-700 mb-1">Subject</label>
            <input
              type="text"
              className="input-field"
              placeholder="Brief description of your issue"
              value={form.subject}
              onChange={(e) => setForm({ ...form, subject: e.target.value })}
              required
              minLength={3}
            />
          </div>

          <div className="grid grid-cols-1 sm:grid-cols-2 gap-4">
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">Department</label>
              <select
                className="input-field"
                value={form.department}
                onChange={(e) => setForm({ ...form, department: e.target.value as TicketDepartment })}
              >
                {availableDepartments.map((dept) => (
                  <option key={dept.value} value={dept.value}>{dept.label}</option>
                ))}
              </select>
            </div>
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-1">Priority</label>
              <select
                className="input-field"
                value={form.priority}
                onChange={(e) => setForm({ ...form, priority: e.target.value as TicketPriority })}
              >
                <option value="low">Low</option>
                <option value="medium">Medium</option>
                <option value="high">High</option>
              </select>
            </div>
          </div>

          <div>
            <label className="block text-sm font-medium text-gray-700 mb-1">Message</label>
            <textarea
              className="input-field min-h-[120px]"
              placeholder="Describe your issue in detail..."
              value={form.message}
              onChange={(e) => setForm({ ...form, message: e.target.value })}
              required
              minLength={10}
            />
          </div>

          <div className="flex justify-end">
            <button type="submit" className="btn-primary" disabled={createMutation.isPending}>
              {createMutation.isPending ? 'Creating...' : 'Submit Ticket'}
            </button>
          </div>
        </form>
      )}

      {/* 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">
          <TicketIcon className="w-10 h-10 mx-auto text-gray-300" />
          <h3 className="mt-3 text-lg font-semibold text-gray-700">No tickets yet</h3>
          <p className="text-sm text-gray-500 mt-1">Create a ticket if you need help</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">
                    <span className="flex items-center gap-1">{ticket.department === 'technical' ? <><Wrench className="w-3 h-3" /> Technical</> : <><Briefcase className="w-3 h-3" /> Sales</>}</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} message{(ticket.messages?.length || 0) !== 1 ? 's' : ''}</span>
                  </div>
                </div>
                <span className="text-gray-400 text-sm">→</span>
              </div>
            </Link>
          ))}
        </div>
      )}
    </div>
  );
}