/**
 * @file the password-manager save — ids reach the browser's storage only by
 * this gesture-gated path (or copy), never localStorage/IndexedDB, which
 * are ambient and XSS-reachable. It runs in the *browser*: pages embed it
 * via `pmSave.toString()`, so it must be self-contained (no imports, no
 * closure, no inner named functions — wrangler's keepNames would wrap
 * those in an `__name` helper the browser doesn't have). Its powers
 * (the petname field, the credential store, the console) are passed in,
 * so tests can stand in for the browser.
 */

/** the browser powers pmSave uses */
export type PmPowers = {
	petname: { value: string };
	credentials?: { store(credential: unknown): Promise<unknown> };
	PasswordCredential?: new (init: { id: string; password: string }) => unknown;
	log: Pick<Console, "info" | "warn" | "error">;
};

/** the button pmSave reports on */
export type PmButton = { textContent: string | null; disabled: boolean };

/**
 * gesture-gated save of `value` under the holder's petname (the PM
 * username).
 *
 * @see https://developer.mozilla.org/en-US/docs/Web/API/CredentialsContainer/store
 */
export function pmSave(btn: PmButton, value: string, powers: PmPowers): Promise<void> {
	const label = powers.petname.value.trim();
	if (!label) {
		btn.textContent = "give it a petname first";
		return Promise.resolve();
	}
	btn.disabled = true;
	if (!powers.PasswordCredential || !powers.credentials) {
		powers.log.warn({ event: "pm-save", outcome: "unsupported", detail: "no PasswordCredential / navigator.credentials" });
		btn.textContent = "browser has no credential store — copy instead";
		btn.disabled = false;
		return Promise.resolve();
	}
	return powers.credentials
		.store(new powers.PasswordCredential({ id: label, password: value }))
		.then(() => {
			// store() resolves with undefined per spec, whether the holder
			// accepted the browser's prompt or not (or no prompt showed):
			// we can only say it was offered — the PM's own UI is the truth
			powers.log.info({ event: "pm-save", outcome: "offered", label });
			btn.textContent = "offered to the password manager ✓ (see its prompt)";
			btn.disabled = false;
		})
		.catch((err) => {
			powers.log.error({ event: "pm-save", error: String(err) });
			btn.textContent = "save failed — copy instead";
			btn.disabled = false;
		});
}