Link deduplicate requests

[oscartbeaumont]

When using the Solid or React integration this is deal with by them.

Do deduplication of queries and mutations inside of the http and websocket links.

[oscartbeaumont]

const activeReqs = new Map<string, BatchedItem[]>(); // TODO: Deduplicate fetches by queryKey hash

// TODO: --- CLEANUP BELOW

export type MapKey = ["path" | "id", string];

export const toMapId = (op: Operation | RspcResponse) =>
  // @ts-expect-error // TODO: Fix this
  ("id" in op ? ["id", op.id] : ["path", op.path]) satisfies MapKey;

// export const toMapId = (op: Operation | RspcResponse) =>
//   "id" in op
//     ? ["id", op.id].join(",")
//     : ["path", op.path, JSON.stringify("TODO: ARG")].join(",");

// Copied from: https://github.com/jonschlinkert/is-plain-object
export function isPlainObject(o: any): o is Object {
  if (!hasObjectPrototype(o)) {
    return false;
  }

  // If has modified constructor
  const ctor = o.constructor;
  if (typeof ctor === "undefined") {
    return true;
  }

  // If has modified prototype
  const prot = ctor.prototype;
  if (!hasObjectPrototype(prot)) {
    return false;
  }

  // If constructor does not have an Object-specific method
  if (!prot.hasOwnProperty("isPrototypeOf")) {
    return false;
  }

  // Most likely a plain Object
  return true;
}

function hasObjectPrototype(o: any): boolean {
  return Object.prototype.toString.call(o) === "[object Object]";
}

// This is copied from the React Query `hashQueryKey` function.
export function hashOperation(queryKey: Operation): string {
  return JSON.stringify(queryKey, (_, val) =>
    isPlainObject(val)
      ? Object.keys(val)
          .sort()
          .reduce((result, key) => {
            result[key] = val[key];
            return result;
          }, {} as any)
      : val
  );
}

export const generateRandomId = () => Math.random().toString(36).slice(2); // TODO: Remove and use incremental counter

function hashedQueryKey() {
  // TSH = (s) => {
  //   for (var i = 0, h = 9; i < s.length; )
  //     h = Math.imul(h ^ s.charCodeAt(i++), 9 ** 9);
  //   return h ^ (h >>> 9);
  // };
}