import { ApolloClient, InMemoryCache, createHttpLink } from "@apollo/client";
import { setContext } from "@apollo/client/link/context";

const httpLink = createHttpLink({
  uri: process.env.NEXT_PUBLIC_SALEOR_API_URL || "http://localhost:8000/graphql/",
});

const authLink = setContext((_, { headers }) => {
  // Saleor doesn't require auth for public queries
  // Add auth token here if needed for admin operations
  return {
    headers: {
      ...headers,
      "Content-Type": "application/json",
    },
  };
});

export const saleorClient = new ApolloClient({
  link: authLink.concat(httpLink),
  cache: new InMemoryCache({
    typePolicies: {
      Query: {
        fields: {
          products: {
            keyArgs: ["channel", "filter"],
            merge(existing, incoming) {
              if (!existing) return incoming;
              return {
                ...incoming,
                edges: [...existing.edges, ...incoming.edges],
              };
            },
          },
        },
      },
    },
  }),
  defaultOptions: {
    watchQuery: {
      fetchPolicy: "cache-first",
    },
    query: {
      fetchPolicy: "cache-first",
    },
  },
});

export default saleorClient;