"use client";

import { useState, useEffect } from "react";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Checkbox } from "@/components/ui/checkbox";
import { ScrollArea } from "@/components/ui/scroll-area";
import { Search, Package } from "lucide-react";
import { apiRequest } from "@/lib/api";

interface Product {
  _id: string;
  name: string;
  description?: string;
  unitType: string;
  pricing: Array<{ minQuantity: number; pricePerUnit: number }>;
  image?: string;
}

interface ProductSelectorProps {
  selectedProducts: string[];
  onSelectionChange: (productIds: string[]) => void;
}

export default function ProductSelector({ selectedProducts, onSelectionChange }: ProductSelectorProps) {
  const [products, setProducts] = useState<Product[]>([]);
  const [loading, setLoading] = useState(true);
  const [searchTerm, setSearchTerm] = useState("");

  useEffect(() => {
    const fetchProducts = async () => {
      try {
        const fetchedProducts = await apiRequest('/products/for-selection', 'GET');
        setProducts(fetchedProducts);
      } catch (error) {
        console.error('Error fetching products:', error);
      } finally {
        setLoading(false);
      }
    };

    fetchProducts();
  }, []);

  const filteredProducts = products.filter(product =>
    product.name.toLowerCase().includes(searchTerm.toLowerCase())
  );

  const handleProductToggle = (productId: string) => {
    const newSelection = selectedProducts.includes(productId)
      ? selectedProducts.filter(id => id !== productId)
      : [...selectedProducts, productId];
    onSelectionChange(newSelection);
  };

  const getMinPrice = (product: Product) => {
    if (!product.pricing || product.pricing.length === 0) return 0;
    const minTier = product.pricing.reduce((min, tier) => 
      tier.pricePerUnit < min.pricePerUnit ? tier : min
    );
    return minTier.pricePerUnit;
  };

  if (loading) {
    return <div className="text-center py-4">Loading products...</div>;
  }

  return (
    <div className="space-y-4">
      <div className="relative">
        <Search className="absolute left-3 top-1/2 transform -translate-y-1/2 h-4 w-4 text-muted-foreground" />
        <Input
          placeholder="Search products..."
          value={searchTerm}
          onChange={(e) => setSearchTerm(e.target.value)}
          className="pl-10"
        />
      </div>

      <ScrollArea className="h-64">
        <div className="space-y-2">
          {filteredProducts.length === 0 ? (
            <div className="text-center py-8 text-muted-foreground">
              <Package className="h-8 w-8 mx-auto mb-2" />
              {searchTerm ? "No products found" : "No products available"}
            </div>
          ) : (
            filteredProducts.map((product) => (
              <div
                key={product._id}
                className="flex items-center space-x-3 p-3 border rounded-lg hover:bg-muted/50"
              >
                <Checkbox
                  checked={selectedProducts.includes(product._id)}
                  onCheckedChange={() => handleProductToggle(product._id)}
                />
                <div className="flex-1 min-w-0">
                  <div className="flex items-center justify-between">
                    <div className="flex-1 min-w-0">
                      <p className="font-medium truncate">{product.name}</p>
                      {product.description && (
                        <p className="text-sm text-muted-foreground truncate">
                          {product.description}
                        </p>
                      )}
                    </div>
                    <div className="text-sm text-muted-foreground ml-2">
                      £{getMinPrice(product).toFixed(2)}
                    </div>
                  </div>
                </div>
              </div>
            ))
          )}
        </div>
      </ScrollArea>

      {selectedProducts.length > 0 && (
        <div className="text-sm text-muted-foreground">
          {selectedProducts.length} product(s) selected
        </div>
      )}
    </div>
  );
}