import { createFileRoute, useNavigate } from '@tanstack/react-router'
import { useState } from 'react'
import { useAuth } from '../lib/auth-context'
import { useGetCart } from '../hooks/cart-query-hooks'
import { useAllProducts } from '../hooks/prominent-api-hooks'
import { ProtectedRoute } from '../components/ProtectedRoute'
import { CheckoutAddressSelector } from '../components/CheckoutAddressSelector'
import { PaymentAndOrderComponent } from '../components/PaymentAndOrderComponent'
import { AddressForm } from '../components/AddressForm'
import { Dialog } from '../components/Dialog'
import { useAddressStore } from '../lib/stores/address-store'
import { useQueryClient } from '@tanstack/react-query'
import { ShoppingCart, ChevronLeft, MapPin } from 'lucide-react'

export const Route = createFileRoute('/checkout')({ component: CheckoutPage })

function CheckoutPage() {
  return (
    <ProtectedRoute>
      <CheckoutContent />
    </ProtectedRoute>
  )
}

function CheckoutContent() {
  const navigate = useNavigate()
  const queryClient = useQueryClient()
  const { isAuthenticated } = useAuth()
  const { selectedAddressId, setSelectedAddressId } = useAddressStore()
  const [showAddAddress, setShowAddAddress] = useState(false)
  const [editingAddress, setEditingAddress] = useState<any>(null)

  const cartType: 'regular' | 'flash' = 'regular'
  const { data: cartData } = useGetCart(cartType)
  const { data: productsData } = useAllProducts()

  const products = productsData?.products || []
  const productsById: Record<number, any> = {}
  products.forEach((p: any) => { productsById[p.id] = p })

  const cartItems = (cartData?.items || []).filter((item) => productsById[item.productId])

  // Handle empty cart case
  if (cartItems.length === 0) {
    return (
      <div className="flex min-h-screen flex-col items-center justify-center bg-gray-50 p-6">
        <div className="flex h-20 w-20 items-center justify-center rounded-2xl bg-white">
          <ShoppingCart className="h-9 w-9 text-gray-400" />
        </div>
        <p className="mt-6 text-xl font-bold text-gray-900">
          Your cart is empty
        </p>
        <p className="mb-6 mt-1 text-gray-500">
          Add some delicious items to your cart before checking out
        </p>
        <button
          onClick={() => navigate({ to: '/home' })}
          className="rounded-lg bg-brand-600 px-6 py-3 text-sm font-bold text-white transition-colors hover:bg-brand-700"
        >
          Back to Shopping
        </button>
      </div>
    )
  }

  return (
    <div className="min-h-screen bg-gray-50">
      {/* Checkout Header */}
      <div className="sticky top-0 z-20 border-b border-gray-200 bg-white">
        <div className="mx-auto flex h-16 w-full max-w-7xl items-center gap-3 px-4 md:px-8">
          <button
            onClick={() => navigate({ to: '/cart' })}
            className="flex h-9 w-9 items-center justify-center rounded-lg text-gray-600 transition-colors hover:bg-gray-50"
            aria-label="Back to cart"
          >
            <ChevronLeft className="h-5 w-5" />
          </button>
          <div className="flex h-9 w-9 items-center justify-center rounded-lg bg-brand-25">
            <MapPin className="h-4 w-4 text-brand-600" />
          </div>
          <p className="font-display text-lg font-extrabold text-gray-900">
            Checkout
          </p>
        </div>
      </div>

      <div className="mx-auto grid w-full max-w-7xl gap-8 px-4 py-6 md:px-8 lg:grid-cols-[minmax(0,1fr)_420px]">
        {/* Left: Address Selection + Payment */}
        <div>
          <CheckoutAddressSelector
            onAddressSelect={setSelectedAddressId}
            onAddAddress={() => {
              setEditingAddress(null)
              setShowAddAddress(true)
            }}
            onEditAddress={(address) => {
              setEditingAddress(address)
              setShowAddAddress(true)
            }}
          />
        </div>

        {/* Right: Order summary + payment */}
        <div className="lg:sticky lg:top-24 lg:self-start">
          <PaymentAndOrderComponent
            selectedAddress={selectedAddressId}
            cartItems={cartItems}
            isFlashDelivery={false}
            onBack={() => navigate({ to: '/cart' })}
          />
        </div>
      </div>

      {/* Add/Edit Address Dialog */}
      <Dialog
        open={showAddAddress}
        onClose={() => {
          setShowAddAddress(false)
          setEditingAddress(null)
        }}
        title={editingAddress ? 'Edit Address' : 'Add Address'}
      >
        <AddressForm
          onSuccess={(addressId) => {
            setShowAddAddress(false)
            setEditingAddress(null)
            if (addressId) {
              setSelectedAddressId(addressId)
            }
            queryClient.invalidateQueries({ queryKey: ['user.address.getUserAddresses'] })
          }}
          initialValues={editingAddress || undefined}
          isEdit={!!editingAddress}
        />
      </Dialog>
    </div>
  )
}