feat: add proxy for CosmosAsync calls

[rxri]

If it's spotify api - add necessary headers
It it's external uri - redirect the request via cors proxy

fixes #2844

[Delusoire]

Would you consider something more like:

	const corsProxyURL = "https://cors-proxy.ririxi.workers.dev/";
	const allowedMethodsMap = {
		get: "get",
		post: "post",
		del: "delete",
		put: "put",
		patch: "patch"
	};
	const allowedMethodsSet = new Set(allowedMethodsMap.keys());
	const internalEndpoints = new Set(["sp", "wg"]);

	const handler = {
		// biome-ignore lint/complexity/useArrowFunction: <explanation>
		get: function (target, prop, receiver) {
			const internalFetch = Reflect.get(target, prop, receiver);

			if (typeof internalFetch !== "function" || !allowedMethodsSet.has(prop) || Spicetify.Platform.version >= "1.2.31") {
				return internalFetch;
			}

			return function (url, paramsOrBody) {
				const urlObj = new URL(url);

				const isWebAPI = urlObj.hostname === "api.spotify.com";
				const isSpClientAPI = urlObj.hostname.includes(".spotify.com") && urlObj.hostname.includes("spclient");
				const isInternalURL =  internalEndpoints.has(urlObj.protocol);
				const shouldUseCORSProxy = !isWebAPI && !isSpClientAPI && !isInternalURL;

				const method = allowedMethodsMap.get(prop.toLowerCase());
				const headers = {
					"Content-Type": "application/json"
				};

				const options = {
					method,
					headers,
					timeout: 1000 * 15
				};
				
				let finalURL = urlObj.toString();
				if (paramsOrBody) {
					if (method === "get") {
						const params = new URLSearchParams(paramsOrBody)
						finalURL += `?${params.toString()}`;
					} else {
						options.body = JSON.stringify(paramsOrBody);
					}
				}
				if (shouldUseCORSProxy) {
					finalURL = `${corsProxyURL}${finalURL}`;
				}

				const Authorization = `Bearer ${Spicetify.Platform.Session.accessToken}`;
				let injectedHeaders = {};
				if (isWebAPI) {
					injectedHeaders = { Authorization };
				};
				if (isSpClientAPI) {
					injectedHeaders = {
						Authorization,
						"Spotify-App-Version": Spicetify.Platform.version,
						"App-Platform": Spicetify.Platform.PlatformData.app_platform
					};
				}
				Object.assign(options.headers, injectedHeaders);

				try {
					if (isInternalURL) {
						return internalFetch.apply(this, args);
					}
					return fetch(finalURL, options).then(res => res.json());
				} catch (e) {
					console.error(e);
				}
			};
		}
	};

Which is pretty much the same with minor variable name & control flow changes.

[rxri]

it's added automatically via biome, I cannot remove the <explanation> part because then it's not valid "ignore line"

[afonsojramos]

Best of luck @rxri, let's hope this all goes well! 🙏

[rxri]

Best of luck @rxri, let's hope this all goes well! 🙏

[kuba2k2]

What about localhost? It should never be proxied, but it is. The cors proxy obviously denies that request.

See kuba2k2/spicetify-beat-saber#14

[rxri]

What about localhost? It should never be proxied, but it is. The cors proxy obviously denies that request.

See kuba2k2/spicetify-beat-saber#14

@kuba2k2 please use fetch in this instance. CosmosAsync shouldn't be used unless you need to bypass cors or want to easily get data from spotify api without managing headers manually