import { useState } from 'react'
import { createFileRoute, useNavigate } from '@tanstack/react-router'
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
import { productListOptions, productMutations, productKeys, categoryAllOptions } from '@/api/inventory'
import { ProductForm } from '@/components/inventory/product-form'
import { usePagination } from '@/hooks/use-pagination'
import { DataTable, type Column } from '@/components/shared/data-table'
import { Badge } from '@/components/ui/badge'
import { Button } from '@/components/ui/button'
import { Input } from '@/components/ui/input'
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select'
import { Dialog, DialogContent, DialogHeader, DialogTitle, DialogTrigger } from '@/components/ui/dialog'
import { Search, Plus } from 'lucide-react'
import { toast } from 'sonner'
import { useAuthStore } from '@/stores/auth.store'
import type { Product } from '@/types/inventory'

export const Route = createFileRoute('/_authenticated/inventory/')({
  validateSearch: (search: Record<string, unknown>) => ({
    page: Number(search.page) || 1,
    limit: Number(search.limit) || 25,
    q: (search.q as string) || undefined,
    sort: (search.sort as string) || undefined,
    order: (search.order as 'asc' | 'desc') || 'asc',
    categoryId: (search.categoryId as string) || undefined,
    isActive: (search.isActive as string) || undefined,
    type: (search.type as string) || undefined,
    lowStock: (search.lowStock as string) || undefined,
  }),
  component: InventoryPage,
})

function qtyBadge(qty: number, reorderPoint: number | null) {
  if (qty === 0) return <Badge variant="destructive">{qty}</Badge>
  if (reorderPoint !== null && qty <= reorderPoint)
    return <Badge variant="secondary" className="bg-amber-100 text-amber-800 border-amber-300">{qty} Low</Badge>
  return <span className="text-sm">{qty}</span>
}

function InventoryPage() {
  const navigate = useNavigate()
  const queryClient = useQueryClient()
  const hasPermission = useAuthStore((s) => s.hasPermission)
  const { params, setPage, setSearch, setSort } = usePagination()
  const [searchInput, setSearchInput] = useState(params.q ?? '')
  const [createOpen, setCreateOpen] = useState(false)

  const search = Route.useSearch()
  const [categoryFilter, setCategoryFilter] = useState(search.categoryId ?? '')
  const [activeFilter, setActiveFilter] = useState(search.isActive ?? '')
  const [typeFilter, setTypeFilter] = useState(search.type ?? '')
  const [lowStockFilter, setLowStockFilter] = useState(search.lowStock === 'true')

  const { data: categoriesData } = useQuery(categoryAllOptions())
  const categories = categoriesData?.data ?? []
  const categoryMap = new Map(categories.map((c) => [c.id, c.name]))

  const queryParams: Record<string, unknown> = { ...params }
  if (categoryFilter) queryParams.categoryId = categoryFilter
  if (activeFilter) queryParams.isActive = activeFilter === 'true'
  if (typeFilter === 'serialized') queryParams.isSerialized = true
  if (typeFilter === 'rental') queryParams.isRental = true
  if (typeFilter === 'repair') queryParams.isDualUseRepair = true
  if (lowStockFilter) queryParams.lowStock = true

  const { data, isLoading } = useQuery(productListOptions(queryParams))

  const createMutation = useMutation({
    mutationFn: productMutations.create,
    onSuccess: (product) => {
      queryClient.invalidateQueries({ queryKey: productKeys.all })
      toast.success('Product created')
      setCreateOpen(false)
      navigate({ to: '/inventory/$productId', params: { productId: product.id }, search: { tab: 'details' } })
    },
    onError: (err) => toast.error(err.message),
  })

  function handleSearchSubmit(e: React.FormEvent) {
    e.preventDefault()
    setSearch(searchInput)
  }

  function handleCategoryChange(v: string) {
    setCategoryFilter(v === 'all' ? '' : v)
    navigate({ to: '/inventory', search: { ...search, categoryId: v === 'all' ? undefined : v, page: 1 } })
  }

  function handleActiveChange(v: string) {
    setActiveFilter(v === 'all' ? '' : v)
    navigate({ to: '/inventory', search: { ...search, isActive: v === 'all' ? undefined : v, page: 1 } })
  }

  function handleTypeChange(v: string) {
    setTypeFilter(v === 'all' ? '' : v)
    navigate({ to: '/inventory', search: { ...search, type: v === 'all' ? undefined : v, page: 1 } })
  }

  function handleLowStockChange(v: string) {
    const on = v === 'true'
    setLowStockFilter(on)
    navigate({ to: '/inventory', search: { ...search, lowStock: on ? 'true' : undefined, page: 1 } })
  }

  const columns: Column<Product>[] = [
    {
      key: 'name',
      header: 'Name',
      sortable: true,
      render: (p) => <span className="font-medium">{p.name}</span>,
    },
    {
      key: 'sku',
      header: 'SKU',
      sortable: true,
      render: (p) => p.sku
        ? <span className="font-mono text-sm">{p.sku}</span>
        : <span className="text-muted-foreground">—</span>,
    },
    {
      key: 'brand',
      header: 'Brand',
      sortable: true,
      render: (p) => p.brand ?? <span className="text-muted-foreground">—</span>,
    },
    {
      key: 'category',
      header: 'Category',
      render: (p) => p.categoryId
        ? (categoryMap.get(p.categoryId) ?? <span className="text-muted-foreground">—</span>)
        : <span className="text-muted-foreground">—</span>,
    },
    {
      key: 'price',
      header: 'Price',
      sortable: true,
      render: (p) => p.price ? `$${Number(p.price).toFixed(2)}` : <span className="text-muted-foreground">—</span>,
    },
    {
      key: 'qty_on_hand',
      header: 'Qty',
      sortable: true,
      render: (p) => qtyBadge(p.qtyOnHand, p.qtyReorderPoint),
    },
    {
      key: 'flags',
      header: 'Type',
      render: (p) => (
        <div className="flex gap-1">
          {p.isSerialized && <Badge variant="outline" className="text-xs">Serial</Badge>}
          {p.isRental && <Badge variant="outline" className="text-xs">Rental</Badge>}
          {p.isDualUseRepair && <Badge variant="outline" className="text-xs">Repair</Badge>}
        </div>
      ),
    },
    {
      key: 'is_active',
      header: 'Status',
      sortable: true,
      render: (p) => p.isActive
        ? <Badge>Active</Badge>
        : <Badge variant="secondary">Inactive</Badge>,
    },
  ]

  return (
    <div className="space-y-6">
      <div className="flex items-center justify-between">
        <h1 className="text-2xl font-bold">Products</h1>
        {hasPermission('inventory.edit') && (
          <Dialog open={createOpen} onOpenChange={setCreateOpen}>
            <DialogTrigger asChild>
              <Button><Plus className="mr-2 h-4 w-4" />New Product</Button>
            </DialogTrigger>
            <DialogContent className="max-w-xl max-h-[90vh] overflow-y-auto">
              <DialogHeader><DialogTitle>New Product</DialogTitle></DialogHeader>
              <ProductForm onSubmit={createMutation.mutate} loading={createMutation.isPending} />
            </DialogContent>
          </Dialog>
        )}
      </div>

      <div className="flex gap-3 flex-wrap">
        <form onSubmit={handleSearchSubmit} className="flex gap-2">
          <div className="relative">
            <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-4 w-4 text-muted-foreground" />
            <Input
              placeholder="Search products..."
              value={searchInput}
              onChange={(e) => setSearchInput(e.target.value)}
              className="pl-9 w-64"
            />
          </div>
          <Button type="submit" variant="secondary">Search</Button>
        </form>
        <Select value={categoryFilter || 'all'} onValueChange={handleCategoryChange}>
          <SelectTrigger className="w-44">
            <SelectValue placeholder="All Categories" />
          </SelectTrigger>
          <SelectContent>
            <SelectItem value="all">All Categories</SelectItem>
            {categories.filter((c) => c.isActive).map((c) => (
              <SelectItem key={c.id} value={c.id}>{c.name}</SelectItem>
            ))}
          </SelectContent>
        </Select>
        <Select value={typeFilter || 'all'} onValueChange={handleTypeChange}>
          <SelectTrigger className="w-36">
            <SelectValue placeholder="All Types" />
          </SelectTrigger>
          <SelectContent>
            <SelectItem value="all">All Types</SelectItem>
            <SelectItem value="serialized">Serialized</SelectItem>
            <SelectItem value="rental">Rental</SelectItem>
            <SelectItem value="repair">Repair Parts</SelectItem>
          </SelectContent>
        </Select>
        <Select value={lowStockFilter ? 'true' : 'all'} onValueChange={handleLowStockChange}>
          <SelectTrigger className="w-36">
            <SelectValue placeholder="All Stock" />
          </SelectTrigger>
          <SelectContent>
            <SelectItem value="all">All Stock</SelectItem>
            <SelectItem value="true">Low / Out of Stock</SelectItem>
          </SelectContent>
        </Select>
        <Select value={activeFilter || 'all'} onValueChange={handleActiveChange}>
          <SelectTrigger className="w-32">
            <SelectValue placeholder="Active" />
          </SelectTrigger>
          <SelectContent>
            <SelectItem value="all">Active</SelectItem>
            <SelectItem value="false">Inactive</SelectItem>
          </SelectContent>
        </Select>
      </div>

      <DataTable
        columns={columns}
        data={data?.data ?? []}
        loading={isLoading}
        page={params.page}
        totalPages={data?.pagination.totalPages ?? 1}
        total={data?.pagination.total ?? 0}
        sort={params.sort}
        order={params.order}
        onPageChange={setPage}
        onSort={setSort}
        onRowClick={(p) => navigate({ to: '/inventory/$productId', params: { productId: p.id }, search: { tab: 'details' } })}
      />
    </div>
  )
}
