/*
 * Copyright 2025 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

import type { TrustedTypePolicyFactory } from "trusted-types";

import { logDevWarning, MSG_TRUSTED_TYPES_POLICY_FAILED } from "./messages.js";

const TRUSTED_TYPES_POLICY_NAME = "@googlemaps/js-api-loader";
type TrustedTypesWindow = Window & {
  trustedTypes?: TrustedTypePolicyFactory;
};

// Try to create a Trusted Types policy when supported. Falls back to a string
// passthrough when Trusted Types is unsupported, blocked by CSP, or already
// registered.

let policy: {
  createScriptURL: (url: string) => string | TrustedScriptURL;
};

const trustedTypes = (window as TrustedTypesWindow).trustedTypes;

if (!trustedTypes) {
  policy = { createScriptURL: (url: string) => url };
} else {
  try {
    policy = trustedTypes.createPolicy(TRUSTED_TYPES_POLICY_NAME, {
      createScriptURL: (url: string) => url,
    });
  } catch (e) {
    logDevWarning(
      MSG_TRUSTED_TYPES_POLICY_FAILED(TRUSTED_TYPES_POLICY_NAME, e)
    );
    policy = { createScriptURL: (url: string) => url };
  }
}

export function setScriptSrc(script: HTMLScriptElement, src: string): void {
  script.src = policy.createScriptURL(src) as string;
}