user.ts

/* Based heavily on code from https://github.com/BitySA/oauth2-auth-code-pkce */

/*

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import assert from "node:assert";
import { webcrypto as crypto } from "node:crypto";
import { mkdirSync, rmSync, writeFileSync } from "node:fs";
import http from "node:http";
import path from "node:path";
import url from "node:url";
import { TextEncoder } from "node:util";
import TOML from "@iarna/toml";
import { fetch } from "undici";
import {
	getConfigCache,
	purgeConfigCaches,
	saveToConfigCache,
} from "../config-cache";
import { NoDefaultValueProvided, select } from "../dialogs";
import { getCloudflareApiEnvironmentFromEnv } from "../environment-variables/misc-variables";
import { UserError } from "../errors";
import { getGlobalWranglerConfigPath } from "../global-wrangler-config-path";
import { CI } from "../is-ci";
import isInteractive from "../is-interactive";
import { logger } from "../logger";
import openInBrowser from "../open-in-browser";
import { parseTOML, readFileSync } from "../parse";
import { domainUsesAccess } from "./access";
import {
	getAuthDomainFromEnv,
	getAuthUrlFromEnv,
	getClientIdFromEnv,
	getCloudflareAccessToken,
	getCloudflareAccountIdFromEnv,
	getCloudflareAPITokenFromEnv,
	getCloudflareGlobalAuthEmailFromEnv,
	getCloudflareGlobalAuthKeyFromEnv,
	getRevokeUrlFromEnv,
	getTokenUrlFromEnv,
} from "./auth-variables";
import { getAccountChoices } from "./choose-account";
import { generateAuthUrl } from "./generate-auth-url";
import { generateRandomState } from "./generate-random-state";
import type { ChooseAccountItem } from "./choose-account";
import type { ParsedUrlQuery } from "node:querystring";

export type ApiCredentials =
	| {
			apiToken: string;
	  }
	| {
			authKey: string;
			authEmail: string;
	  };

/**
 * Try to read an API token or Global Auth from the environment.
 */
export function getAuthFromEnv(): ApiCredentials | undefined {
	const globalApiKey = getCloudflareGlobalAuthKeyFromEnv();
	const globalApiEmail = getCloudflareGlobalAuthEmailFromEnv();
	const apiToken = getCloudflareAPITokenFromEnv();

	if (globalApiKey && globalApiEmail) {
		return { authKey: globalApiKey, authEmail: globalApiEmail };
	} else if (apiToken) {
		return { apiToken };
	}
}

/**
 * An implementation of rfc6749#section-4.1 and rfc7636.
 */

interface PKCECodes {
	codeChallenge: string;
	codeVerifier: string;
}

/**
 * The module level state of the authentication flow.
 */
interface State extends AuthTokens {
	authorizationCode?: string;
	codeChallenge?: string;
	codeVerifier?: string;
	hasAuthCodeBeenExchangedForAccessToken?: boolean;
	stateQueryParam?: string;
	scopes?: Scope[];
}

/**
 * The tokens related to authentication.
 */
interface AuthTokens {
	accessToken?: AccessToken;
	refreshToken?: RefreshToken;
	scopes?: Scope[];
	/** @deprecated - this field was only provided by the deprecated v1 `wrangler config` command. */
	apiToken?: string;
}

/**
 * The path to the config file that holds user authentication data,
 * relative to the user's home directory.
 */
export const USER_AUTH_CONFIG_PATH = "config";

/**
 * The data that may be read from the `USER_CONFIG_FILE`.
 */
export interface UserAuthConfig {
	oauth_token?: string;
	refresh_token?: string;
	expiration_time?: string;
	scopes?: string[];
	/** @deprecated - this field was only provided by the deprecated v1 `wrangler config` command. */
	api_token?: string;
}

interface RefreshToken {
	value: string;
}

interface AccessToken {
	value: string;
	expiry: string;
}

const DefaultScopes = {
	"account:read":
		"See your account info such as account details, analytics, and memberships.",
	"user:read":
		"See your user info such as name, email address, and account memberships.",
	"workers:write":
		"See and change Cloudflare Workers data such as zones, KV storage, namespaces, scripts, and routes.",
	"workers_kv:write":
		"See and change Cloudflare Workers KV Storage data such as keys and namespaces.",
	"workers_routes:write":
		"See and change Cloudflare Workers data such as filters and routes.",
	"workers_scripts:write":
		"See and change Cloudflare Workers scripts, durable objects, subdomains, triggers, and tail data.",
	"workers_tail:read": "See Cloudflare Workers tail and script data.",
	"d1:write": "See and change D1 Databases.",
	"pages:write":
		"See and change Cloudflare Pages projects, settings and deployments.",
	"zone:read": "Grants read level access to account zone.",
	"ssl_certs:write": "See and manage mTLS certificates for your account",
	"constellation:write": "Manage Constellation projects/models",
	"ai:write": "See and change Workers AI catalog and assets",
	"queues:write": "See and change Cloudflare Queues settings and data",
} as const;

const OptionalScopes = {
	"cloudchamber:write": "Manage Cloudchamber",
} as const;

const AllScopes = {
	...DefaultScopes,
	...OptionalScopes,
};

/**
 * The possible keys for a Scope.
 *
 * "offline_access" is automatically included.
 */
type Scope = keyof typeof AllScopes;

let DefaultScopeKeys = Object.keys(DefaultScopes) as Scope[];

export function setLoginScopeKeys(scopes: Scope[]) {
	DefaultScopeKeys = scopes;
}

export function validateScopeKeys(
	scopes: string[]
): scopes is typeof DefaultScopeKeys {
	return scopes.every((scope) => scope in DefaultScopes);
}

const CALLBACK_URL = "http://localhost:8976/oauth/callback";

let LocalState: State = {
	...getAuthTokens(),
};

/**
 * Compute the current auth tokens.
 */
function getAuthTokens(config?: UserAuthConfig): AuthTokens | undefined {
	// get refreshToken/accessToken from fs if exists
	try {
		// if the environment variable is available, we don't need to do anything here
		if (getAuthFromEnv()) {
			return;
		}

		// otherwise try loading from the user auth config file.
		const { oauth_token, refresh_token, expiration_time, scopes, api_token } =
			config || readAuthConfigFile();

		if (oauth_token) {
			return {
				accessToken: {
					value: oauth_token,
					// If there is no `expiration_time` field then set it to an old date, to cause it to expire immediately.
					expiry: expiration_time ?? "2000-01-01:00:00:00+00:00",
				},
				refreshToken: { value: refresh_token ?? "" },
				scopes: scopes as Scope[],
			};
		} else if (api_token) {
			logger.warn(
				"It looks like you have used Wrangler v1's `config` command to login with an API token.\n" +
					"This is no longer supported in the current version of Wrangler.\n" +
					"If you wish to authenticate via an API token then please set the `CLOUDFLARE_API_TOKEN` environment variable."
			);
			return { apiToken: api_token };
		}
	} catch {
		return undefined;
	}
}

/**
 * Run the initialization of the auth state, in the case that something changed.
 *
 * This runs automatically whenever `writeAuthConfigFile` is run, so generally
 * you won't need to call it yourself.
 */
export function reinitialiseAuthTokens(): void;

/**
 * Reinitialise auth state from an in-memory config, skipping
 * over the part where we write a file and then read it back into memory
 */
export function reinitialiseAuthTokens(config: UserAuthConfig): void;

export function reinitialiseAuthTokens(config?: UserAuthConfig): void {
	LocalState = {
		...getAuthTokens(config),
	};
}

export function getAPIToken(): ApiCredentials | undefined {
	if (LocalState.apiToken) {
		return { apiToken: LocalState.apiToken };
	}

	const localAPIToken = getAuthFromEnv();
	if (localAPIToken) {
		return localAPIToken;
	}

	const storedAccessToken = LocalState.accessToken?.value;
	if (storedAccessToken) {
		return { apiToken: storedAccessToken };
	}

	return undefined;
}

interface AccessContext {
	token?: AccessToken;
	scopes?: Scope[];
	refreshToken?: RefreshToken;
}

/**
 * A list of OAuth2AuthCodePKCE errors.
 */
// To "namespace" all errors.
class ErrorOAuth2 extends UserError {
	toString(): string {
		return "ErrorOAuth2";
	}
}

// For really unknown errors.
class ErrorUnknown extends Error {
	toString(): string {
		return "ErrorUnknown";
	}
}

// Some generic, internal errors that can happen.
class ErrorNoAuthCode extends ErrorOAuth2 {
	toString(): string {
		return "ErrorNoAuthCode";
	}
}
class ErrorInvalidReturnedStateParam extends ErrorOAuth2 {
	toString(): string {
		return "ErrorInvalidReturnedStateParam";
	}
}
class ErrorInvalidJson extends ErrorOAuth2 {
	toString(): string {
		return "ErrorInvalidJson";
	}
}

// Errors that occur across many endpoints
class ErrorInvalidScope extends ErrorOAuth2 {
	toString(): string {
		return "ErrorInvalidScope";
	}
}
class ErrorInvalidRequest extends ErrorOAuth2 {
	toString(): string {
		return "ErrorInvalidRequest";
	}
}
class ErrorInvalidToken extends ErrorOAuth2 {
	toString(): string {
		return "ErrorInvalidToken";
	}
}

/**
 * Possible authorization grant errors given by the redirection from the
 * authorization server.
 */
class ErrorAuthenticationGrant extends ErrorOAuth2 {
	toString(): string {
		return "ErrorAuthenticationGrant";
	}
}
class ErrorUnauthorizedClient extends ErrorAuthenticationGrant {
	toString(): string {
		return "ErrorUnauthorizedClient";
	}
}
class ErrorAccessDenied extends ErrorAuthenticationGrant {
	toString(): string {
		return "ErrorAccessDenied";
	}
}
class ErrorUnsupportedResponseType extends ErrorAuthenticationGrant {
	toString(): string {
		return "ErrorUnsupportedResponseType";
	}
}
class ErrorServerError extends ErrorAuthenticationGrant {
	toString(): string {
		return "ErrorServerError";
	}
}
class ErrorTemporarilyUnavailable extends ErrorAuthenticationGrant {
	toString(): string {
		return "ErrorTemporarilyUnavailable";
	}
}

/**
 * A list of possible access token response errors.
 */
class ErrorAccessTokenResponse extends ErrorOAuth2 {
	toString(): string {
		return "ErrorAccessTokenResponse";
	}
}
class ErrorInvalidClient extends ErrorAccessTokenResponse {
	toString(): string {
		return "ErrorInvalidClient";
	}
}
class ErrorInvalidGrant extends ErrorAccessTokenResponse {
	toString(): string {
		return "ErrorInvalidGrant";
	}
}
class ErrorUnsupportedGrantType extends ErrorAccessTokenResponse {
	toString(): string {
		return "ErrorUnsupportedGrantType";
	}
}

const RawErrorToErrorClassMap: { [_: string]: typeof ErrorOAuth2 } = {
	invalid_request: ErrorInvalidRequest,
	invalid_grant: ErrorInvalidGrant,
	unauthorized_client: ErrorUnauthorizedClient,
	access_denied: ErrorAccessDenied,
	unsupported_response_type: ErrorUnsupportedResponseType,
	invalid_scope: ErrorInvalidScope,
	server_error: ErrorServerError,
	temporarily_unavailable: ErrorTemporarilyUnavailable,
	invalid_client: ErrorInvalidClient,
	unsupported_grant_type: ErrorUnsupportedGrantType,
	invalid_json: ErrorInvalidJson,
	invalid_token: ErrorInvalidToken,
};

/**
 * Translate the raw error strings returned from the server into error classes.
 */
function toErrorClass(rawError: string): ErrorOAuth2 {
	return new (RawErrorToErrorClassMap[rawError] || ErrorUnknown)();
}

/**
 * The maximum length for a code verifier for the best security we can offer.
 * Please note the NOTE section of RFC 7636 § 4.1 - the length must be >= 43,
 * but <= 128, **after** base64 url encoding. This means 32 code verifier bytes
 * encoded will be 43 bytes, or 96 bytes encoded will be 128 bytes. So 96 bytes
 * is the highest valid value that can be used.
 */
const RECOMMENDED_CODE_VERIFIER_LENGTH = 96;

/**
 * A sensible length for the state's length, for anti-csrf.
 */
const RECOMMENDED_STATE_LENGTH = 32;

/**
 * Character set to generate code verifier defined in rfc7636.
 */
export const PKCE_CHARSET =
	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~";

/**
 * OAuth 2.0 client that ONLY supports authorization code flow, with PKCE.
 */

/**
 * If there is an error, it will be passed back as a rejected Promise.
 * If there is no code, the user should be redirected via
 * [fetchAuthorizationCode].
 */
function isReturningFromAuthServer(query: ParsedUrlQuery): boolean {
	if (query.error) {
		if (Array.isArray(query.error)) {
			throw toErrorClass(query.error[0]);
		}
		throw toErrorClass(query.error);
	}

	const code = query.code;
	if (!code) {
		return false;
	}

	const state = LocalState;

	const stateQueryParam = query.state;
	if (stateQueryParam !== state.stateQueryParam) {
		logger.warn(
			"Received query string parameter doesn't match the one sent! Possible malicious activity somewhere."
		);
		throw new ErrorInvalidReturnedStateParam();
	}
	assert(!Array.isArray(code));
	state.authorizationCode = code;
	state.hasAuthCodeBeenExchangedForAccessToken = false;
	return true;
}

export async function getAuthURL(scopes = DefaultScopeKeys): Promise<string> {
	const { codeChallenge, codeVerifier } = await generatePKCECodes();
	const stateQueryParam = generateRandomState(RECOMMENDED_STATE_LENGTH);

	Object.assign(LocalState, {
		codeChallenge,
		codeVerifier,
		stateQueryParam,
	});

	return generateAuthUrl({
		authUrl: getAuthUrlFromEnv(),
		clientId: getClientIdFromEnv(),
		callbackUrl: CALLBACK_URL,
		scopes,
		stateQueryParam,
		codeChallenge,
	});
}

type TokenResponse =
	| {
			access_token: string;
			expires_in: number;
			refresh_token: string;
			scope: string;
	  }
	| {
			error: string;
	  };

/**
 * Refresh an access token from the remote service.
 */
async function exchangeRefreshTokenForAccessToken(): Promise<AccessContext> {
	if (!LocalState.refreshToken) {
		logger.warn("No refresh token is present.");
	}

	const params = new URLSearchParams({
		grant_type: "refresh_token",
		refresh_token: LocalState.refreshToken?.value ?? "",
		client_id: getClientIdFromEnv(),
	});

	const response = await fetchAuthToken(params);

	if (response.status >= 400) {
		let tokenExchangeResErr = undefined;

		try {
			tokenExchangeResErr = await response.text();
			tokenExchangeResErr = JSON.parse(tokenExchangeResErr);
		} catch (e) {
			// If it can't parse to JSON ignore the error
		}

		if (tokenExchangeResErr !== undefined) {
			// We will throw the parsed error if it parsed correctly, otherwise we throw an unknown error.
			throw typeof tokenExchangeResErr === "string"
				? new Error(tokenExchangeResErr)
				: tokenExchangeResErr;
		} else {
			throw new ErrorUnknown(
				"Failed to parse Error from exchangeRefreshTokenForAccessToken"
			);
		}
	} else {
		try {
			const json = (await response.json()) as TokenResponse;
			if ("error" in json) {
				throw json.error;
			}

			const { access_token, expires_in, refresh_token, scope } = json;
			let scopes: Scope[] = [];

			const accessToken: AccessToken = {
				value: access_token,
				expiry: new Date(Date.now() + expires_in * 1000).toISOString(),
			};
			LocalState.accessToken = accessToken;

			if (refresh_token) {
				LocalState.refreshToken = {
					value: refresh_token,
				};
			}

			if (scope) {
				// Multiple scopes are passed and delimited by spaces,
				// despite using the singular name "scope".
				scopes = scope.split(" ") as Scope[];
				LocalState.scopes = scopes;
			}

			const accessContext: AccessContext = {
				token: accessToken,
				scopes,
				refreshToken: LocalState.refreshToken,
			};
			return accessContext;
		} catch (error) {
			if (typeof error === "string") {
				throw toErrorClass(error);
			} else {
				throw error;
			}
		}
	}
}

/**
 * Fetch an access token from the remote service.
 */
async function exchangeAuthCodeForAccessToken(): Promise<AccessContext> {
	const { authorizationCode, codeVerifier = "" } = LocalState;

	if (!codeVerifier) {
		logger.warn("No code verifier is being sent.");
	} else if (!authorizationCode) {
		logger.warn("No authorization grant code is being passed.");
	}

	const params = new URLSearchParams({
		grant_type: `authorization_code`,
		code: authorizationCode ?? "",
		redirect_uri: CALLBACK_URL,
		client_id: getClientIdFromEnv(),
		code_verifier: codeVerifier,
	});

	const response = await fetchAuthToken(params);
	if (!response.ok) {
		const { error } = (await response.json()) as { error: string };
		// .catch((_) => ({ error: "invalid_json" }));
		if (error === "invalid_grant") {
			logger.log("Expired! Auth code or refresh token needs to be renewed.");
			// alert("Redirecting to auth server to obtain a new auth grant code.");
			// TODO: return refreshAuthCodeOrRefreshToken();
		}
		throw toErrorClass(error);
	}
	const json = (await response.json()) as TokenResponse;
	if ("error" in json) {
		throw new Error(json.error);
	}
	const { access_token, expires_in, refresh_token, scope } = json;
	let scopes: Scope[] = [];
	LocalState.hasAuthCodeBeenExchangedForAccessToken = true;

	const expiryDate = new Date(Date.now() + expires_in * 1000);
	const accessToken: AccessToken = {
		value: access_token,
		expiry: expiryDate.toISOString(),
	};
	LocalState.accessToken = accessToken;

	if (refresh_token) {
		LocalState.refreshToken = {
			value: refresh_token,
		};
	}

	if (scope) {
		// Multiple scopes are passed and delimited by spaces,
		// despite using the singular name "scope".
		scopes = scope.split(" ") as Scope[];
		LocalState.scopes = scopes;
	}

	const accessContext: AccessContext = {
		token: accessToken,
		scopes,
		refreshToken: LocalState.refreshToken,
	};
	return accessContext;
}

/**
 * Implements *base64url-encode* (RFC 4648 § 5) without padding, which is NOT
 * the same as regular base64 encoding.
 */
function base64urlEncode(value: string): string {
	let base64 = btoa(value);
	base64 = base64.replace(/\+/g, "-");
	base64 = base64.replace(/\//g, "_");
	base64 = base64.replace(/=/g, "");
	return base64;
}

/**
 * Generates a code_verifier and code_challenge, as specified in rfc7636.
 */

async function generatePKCECodes(): Promise<PKCECodes> {
	const output = new Uint32Array(RECOMMENDED_CODE_VERIFIER_LENGTH);
	crypto.getRandomValues(output);
	const codeVerifier = base64urlEncode(
		Array.from(output)
			.map((num: number) => PKCE_CHARSET[num % PKCE_CHARSET.length])
			.join("")
	);
	const buffer = await crypto.subtle.digest(
		"SHA-256",
		new TextEncoder().encode(codeVerifier)
	);
	const hash = new Uint8Array(buffer);
	let binary = "";
	const hashLength = hash.byteLength;
	for (let i = 0; i < hashLength; i++) {
		binary += String.fromCharCode(hash[i]);
	}
	const codeChallenge = base64urlEncode(binary);
	return { codeChallenge, codeVerifier };
}

export function getAuthConfigFilePath() {
	const environment = getCloudflareApiEnvironmentFromEnv();
	const filePath = `${USER_AUTH_CONFIG_PATH}/${environment === "production" ? "default.toml" : `${environment}.toml`}`;

	return path.join(getGlobalWranglerConfigPath(), filePath);
}

/**
 * Writes a a wrangler config file (auth credentials) to disk,
 * and updates the user auth state with the new credentials.
 */
export function writeAuthConfigFile(config: UserAuthConfig) {
	const configPath = getAuthConfigFilePath();

	mkdirSync(path.dirname(configPath), {
		recursive: true,
	});
	writeFileSync(path.join(configPath), TOML.stringify(config as TOML.JsonMap), {
		encoding: "utf-8",
	});

	reinitialiseAuthTokens();
}

export function readAuthConfigFile(): UserAuthConfig {
	const toml = parseTOML(readFileSync(getAuthConfigFilePath()));
	return toml;
}

type LoginProps = {
	scopes?: Scope[];
	browser: boolean;
};

export async function loginOrRefreshIfRequired(
	props?: LoginProps
): Promise<boolean> {
	// TODO: if there already is a token, then try refreshing
	// TODO: ask permission before opening browser
	const { isCI } = CI;
	if (!getAPIToken()) {
		// Not logged in.
		// If we are not interactive, we cannot ask the user to login
		return isInteractive() && !isCI() && (await login(props));
	} else if (isAccessTokenExpired()) {
		// We're logged in, but the refresh token seems to have expired,
		// so let's try to refresh it
		const didRefresh = await refreshToken();
		if (didRefresh) {
			// The token was refreshed, so we're done here
			return true;
		} else {
			// If the refresh token isn't valid, then we ask the user to login again
			return isInteractive() && !isCI() && (await login(props));
		}
	} else {
		return true;
	}
}

export async function login(
	props: LoginProps = { browser: true }
): Promise<boolean> {
	logger.log("Attempting to login via OAuth...");
	const urlToOpen = await getAuthURL(props?.scopes);
	let server: http.Server;
	let loginTimeoutHandle: NodeJS.Timeout;
	const timerPromise = new Promise<boolean>((resolve) => {
		loginTimeoutHandle = setTimeout(() => {
			logger.error(
				"Timed out waiting for authorization code, please try again."
			);
			server.close();
			clearTimeout(loginTimeoutHandle);
			resolve(false);
		}, 120000); // wait for 120 seconds for the user to authorize
	});

	const loginPromise = new Promise<boolean>((resolve, reject) => {
		server = http.createServer(async (req, res) => {
			function finish(status: boolean, error?: Error) {
				clearTimeout(loginTimeoutHandle);
				server.close((closeErr?: Error) => {
					if (error || closeErr) {
						reject(error || closeErr);
					} else {
						resolve(status);
					}
				});
			}

			assert(req.url, "This request doesn't have a URL"); // This should never happen
			const { pathname, query } = url.parse(req.url, true);
			if (req.method !== "GET") {
				return res.end("OK");
			}
			switch (pathname) {
				case "/oauth/callback": {
					let hasAuthCode = false;
					try {
						hasAuthCode = isReturningFromAuthServer(query);
					} catch (err: unknown) {
						if (err instanceof ErrorAccessDenied) {
							res.writeHead(307, {
								Location:
									"https://welcome.developers.workers.dev/wrangler-oauth-consent-denied",
							});
							res.end(() => {
								finish(false);
							});
							logger.error(
								"Error: Consent denied. You must grant consent to Wrangler in order to login.\n" +
									"If you don't want to do this consider passing an API token via the `CLOUDFLARE_API_TOKEN` environment variable"
							);

							return;
						} else {
							finish(false, err as Error);
							return;
						}
					}
					if (!hasAuthCode) {
						// render an error page here
						finish(false, new ErrorNoAuthCode());
						return;
					} else {
						const exchange = await exchangeAuthCodeForAccessToken();
						writeAuthConfigFile({
							oauth_token: exchange.token?.value ?? "",
							expiration_time: exchange.token?.expiry,
							refresh_token: exchange.refreshToken?.value,
							scopes: exchange.scopes,
						});
						res.writeHead(307, {
							Location:
								"https://welcome.developers.workers.dev/wrangler-oauth-consent-granted",
						});
						res.end(() => {
							finish(true);
						});
						logger.log(`Successfully logged in.`);

						purgeConfigCaches();

						return;
					}
				}
			}
		});

		server.listen(8976, "localhost");
	});
	if (props?.browser) {
		logger.log(`Opening a link in your default browser: ${urlToOpen}`);
		await openInBrowser(urlToOpen);
	} else {
		logger.log(`Visit this link to authenticate: ${urlToOpen}`);
	}

	return Promise.race([timerPromise, loginPromise]);
}

/**
 * Checks to see if the access token has expired.
 */
function isAccessTokenExpired(): boolean {
	const { accessToken } = LocalState;
	return Boolean(accessToken && new Date() >= new Date(accessToken.expiry));
}

async function refreshToken(): Promise<boolean> {
	// refresh
	try {
		const {
			token: { value: oauth_token, expiry: expiration_time } = {
				value: "",
				expiry: "",
			},
			refreshToken: { value: refresh_token } = {},
			scopes,
		} = await exchangeRefreshTokenForAccessToken();
		writeAuthConfigFile({
			oauth_token,
			expiration_time,
			refresh_token,
			scopes,
		});
		return true;
	} catch (err) {
		return false;
	}
}

export async function logout(): Promise<void> {
	if (!LocalState.accessToken) {
		if (!LocalState.refreshToken) {
			logger.log("Not logged in, exiting...");
			return;
		}

		const body =
			`client_id=${encodeURIComponent(getClientIdFromEnv())}&` +
			`token_type_hint=refresh_token&` +
			`token=${encodeURIComponent(LocalState.refreshToken?.value || "")}`;

		const response = await fetch(getRevokeUrlFromEnv(), {
			method: "POST",
			body,
			headers: {
				"Content-Type": "application/x-www-form-urlencoded",
			},
		});
		await response.text(); // blank text? would be nice if it was something meaningful
		logger.log(
			"💁  Wrangler is configured with an OAuth token. The token has been successfully revoked"
		);
	}
	const body =
		`client_id=${encodeURIComponent(getClientIdFromEnv())}&` +
		`token_type_hint=refresh_token&` +
		`token=${encodeURIComponent(LocalState.refreshToken?.value || "")}`;

	const response = await fetch(getRevokeUrlFromEnv(), {
		method: "POST",
		body,
		headers: {
			"Content-Type": "application/x-www-form-urlencoded",
		},
	});
	await response.text(); // blank text? would be nice if it was something meaningful
	rmSync(getAuthConfigFilePath());
	logger.log(`Successfully logged out.`);
}

export function listScopes(message = "💁 Available scopes:"): void {
	logger.log(message);
	const data = DefaultScopeKeys.map((scope: Scope) => ({
		Scope: scope,
		Description: AllScopes[scope],
	}));
	logger.table(data);
	// TODO: maybe a good idea to show usage here
}

export async function getAccountId(): Promise<string | undefined> {
	const apiToken = getAPIToken();
	if (!apiToken) {
		return;
	}

	// check if we have a cached value
	const cachedAccount = getAccountFromCache();
	if (cachedAccount && !getCloudflareAccountIdFromEnv()) {
		return cachedAccount.id;
	}

	const accounts = await getAccountChoices();
	if (accounts.length === 1) {
		saveAccountToCache({ id: accounts[0].id, name: accounts[0].name });
		return accounts[0].id;
	}

	try {
		const accountID = await select("Select an account", {
			choices: accounts.map((account) => ({
				title: account.name,
				value: account.id,
			})),
		});
		const account = accounts.find(
			(a) => a.id === accountID
		) as ChooseAccountItem;
		saveAccountToCache({ id: account.id, name: account.name });
		return accountID;
	} catch (e) {
		// Did we try to select an account in CI or a non-interactive terminal?
		if (e instanceof NoDefaultValueProvided) {
			throw new UserError(
				`More than one account available but unable to select one in non-interactive mode.
Please set the appropriate \`account_id\` in your \`wrangler.toml\` file.
Available accounts are (\`<name>\`: \`<account_id>\`):
${accounts
	.map((account) => `  \`${account.name}\`: \`${account.id}\``)
	.join("\n")}`
			);
		}
		throw e;
	}
}

/**
 * Ensure that a user is logged in, and a valid account_id is available.
 */
export async function requireAuth(config: {
	account_id?: string;
}): Promise<string> {
	const loggedIn = await loginOrRefreshIfRequired();
	if (!loggedIn) {
		if (!isInteractive() || CI.isCI()) {
			throw new UserError(
				"In a non-interactive environment, it's necessary to set a CLOUDFLARE_API_TOKEN environment variable for wrangler to work. Please go to https://developers.cloudflare.com/fundamentals/api/get-started/create-token/ for instructions on how to create an api token, and assign its value to CLOUDFLARE_API_TOKEN."
			);
		} else {
			// didn't login, let's just quit
			throw new UserError("Did not login, quitting...");
		}
	}
	const accountId = config.account_id || (await getAccountId());
	if (!accountId) {
		throw new UserError("No account id found, quitting...");
	}

	return accountId;
}

/**
 * Throw an error if there is no API token available.
 */
export function requireApiToken(): ApiCredentials {
	const credentials = getAPIToken();
	if (!credentials) {
		throw new UserError("No API token found.");
	}
	return credentials;
}

/**
 * Save the given account details to a cache
 */
export function saveAccountToCache(account: {
	id: string;
	name: string;
}): void {
	saveToConfigCache<{ account: { id: string; name: string } }>(
		"wrangler-account.json",
		{ account }
	);
}

/**
 * Fetch the given account details from a cache if available
 */
export function getAccountFromCache():
	| undefined
	| { id: string; name: string } {
	return getConfigCache<{ account: { id: string; name: string } }>(
		"wrangler-account.json"
	).account;
}

/**
 * Get the scopes of the following token, will only return scopes
 * if the token is an OAuth token.
 */
export function getScopes(): Scope[] | undefined {
	return LocalState.scopes;
}

/**
 * Make a request to the Cloudflare OAuth endpoint to get a token.
 *
 * Note that the `body` of the POST request is form-urlencoded so
 * can be represented by a URLSearchParams object.
 */
async function fetchAuthToken(body: URLSearchParams) {
	const headers: Record<string, string> = {
		"Content-Type": "application/x-www-form-urlencoded",
	};
	if (await domainUsesAccess(getAuthDomainFromEnv())) {
		// We are trying to access the staging API so we need an "access token".
		headers["Cookie"] = `CF_Authorization=${await getCloudflareAccessToken()}`;
	}
	return await fetch(getTokenUrlFromEnv(), {
		method: "POST",
		body: body.toString(),
		headers,
	});
}