// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
import { isSemVer } from "./is_semver.ts";
import { isValidOperator } from "./_shared.ts";
import type { SemVerComparator } from "./types.ts";
import { ALL, NONE } from "./constants.ts";

/**
 * Does a deep check on the value to see if it is a valid SemVerComparator object.
 *
 * Objects with extra fields are still considered valid if they have at
 * least the correct fields.
 *
 * Adds a type assertion if true.
 * @param value The value to check if its a SemVerComparator
 * @returns True if the object is a SemVerComparator otherwise false
 */
export function isSemVerComparator(value: unknown): value is SemVerComparator {
  if (value === null || value === undefined) return false;
  if (value === NONE) return true;
  if (value === ALL) return true;
  if (Array.isArray(value)) return false;
  if (typeof value !== "object") return false;
  const { operator, semver, min, max } = value as SemVerComparator;
  return (
    isValidOperator(operator) &&
    isSemVer(semver) &&
    isSemVer(min) &&
    isSemVer(max)
  );
}