/*
 * CACKey SSH Agent for ChromeOS
 */

cackeySSHAgentApprovedApps = [
	"pnhechapfaindjhompbnflcldabbghjo",
	"okddffdblfhhnmhodogpojmfkjmhinfp"
];

/*
 * XXX:TODO: Expose UI for this
 */
cackeySSHAgentFeatures = {
	enabled: true,
	includeKeys: true,
	includeCerts: true,
	legacy: false
};

/*
 * Feature support checking
 */
function cackeySSHAgentGetSSHKeyTypes() {
	var types = [];

	if (cackeySSHAgentFeatures.includeKeys) {
		types.push("ssh");
	}

	if (cackeySSHAgentFeatures.includeCerts) {
		types.push("x509v3-ssh");

		if (cackeySSHAgentFeatures.legacy) {
			types.push("x509v3-sign");
		}
	}

	return(types);
}

async function cackeySSHAgentGetCertificates() {
	var certs;

	if (!cackeySSHAgentFeatures.enabled) {
		return([]);
	}

	certs = await cackeyListCertificates();

	return(certs);
}

/*
 * SSH Element Encoding/Decoding
 */
function cackeySSHAgentEncodeInt(uint32) {
	var result;

			while (bigInt) {
				result.push(bigInt & 0xff);
				bigInt = bigInt >> 8;
			}
			result.reverse();
			break;
		case "object":

			result = Array.from(new Uint8Array(bigInt.toByteArray()));


			break;
	}

	result = cackeySSHAgentEncodeLV(result);

	return(result);
}

	result = input.slice(0, info.value);

	return({
		value: result,
		output: input.slice(info.value)
	});
}

function cackeySSHAgentEncodeArray(input) {
	var result;

	result = cackeySSHAgentEncodeInt(input.length);
	input.forEach(function(element) {
		result = result.concat(element);
	});

	return(result);
}

function cackeySSHAgentEncodeToUTF8Array(str) {
	var utf8 = [];

	if (typeof(str) === "string") {
		str = str.split("").map(function(c) {
			return(c.charCodeAt(0));

			buffer = buffer.join("");
			break;
	}

	return(buffer);
}

function cackeySSHAgentEncodeCertToKeyAndID(cert, keyType) {
	var result = null, resultKey = null;
	var certObj, certBytes;
	var publicKey;

	certObj = new X509;
	if (!certObj) {
		return(result);
	}

	certBytes = Array.from(new Uint8Array(cert));

	certObj.readCertHex(cackeySSHAgentEncodeBinaryToHex(certBytes));

	publicKey = certObj.getPublicKey();

	switch (keyType) {
		case "ssh":
			switch (publicKey.type) {
				case "RSA":
					resultKey = cackeySSHAgentEncodeString("ssh-rsa");
					resultKey = resultKey.concat(cackeySSHAgentEncodeBigInt(publicKey.e));
					resultKey = resultKey.concat(cackeySSHAgentEncodeBigInt(publicKey.n));
					break;
				default:
					console.log("[cackeySSH] Unsupported public key type:", keyType, "/", publicKey.type, "-- ignoring.");
					break;
			}
			break;
		case "x509v3-sign":
			resultKey = certBytes;
			break;
		case "x509v3-ssh":
			switch (publicKey.type) {
				case "RSA":
					resultKey = cackeySSHAgentEncodeString("x509v3-ssh-rsa");

					/*
					 * Array of certificates
					 */
					resultKey = resultKey.concat(cackeySSHAgentEncodeArray([
						cackeySSHAgentEncodeLV(certBytes)
					]));

					/*
					 * Array of OCSP responses
					 */
					resultKey = resultKey.concat(cackeySSHAgentEncodeArray([]));
					break;
				default:
					console.log("[cackeySSH] Unsupported public key type:", keyType, "/", publicKey.type, "-- ignoring.");
					break;
			}
			break;
		default:
			console.log("[cackeySSH] Unsupported SSH key type:", keyType, "-- ignoring.");
			break;
	}

	if (resultKey) {
		result = {
			id: certObj.getSubjectString(),
			publicKeyType: publicKey.type,
			sshKeyType: keyType,
			key: resultKey
		};
	}

	return(result);
}

/*
 * Command Handlers
 */
async function cackeySSHAgentCommandRequestIdentity(request) {
	var response;
	var certs = [];
	var keys = [];

	/*
	 * Get a list of certificates
	 */
	certs = await cackeySSHAgentGetCertificates();

	/*
	 * Convert each certificate to an SSH key blob
	 */
	cackeySSHAgentGetSSHKeyTypes().forEach(function(sshKeyType) {
		certs.forEach(function(cert) {
			var key;

			key = cackeySSHAgentEncodeCertToKeyAndID(cert.certificate, sshKeyType);

			if (key) {
				keys.push(key);
			}
		});
	});

	/*
	 * Encode response
	 */
	response = [];

	flags = cackeySSHAgentDecodeInt(request);
	request = flags.output;
	flags = flags.value;

	/*
	 * Find the certificate that matches the requested key
	 */
	certs = await cackeySSHAgentGetCertificates();
	certToUse = null;
	cackeySSHAgentGetSSHKeyTypes().forEach(function(sshKeyType) {
		certs.forEach(function(cert) {
			var key;

			key = cackeySSHAgentEncodeCertToKeyAndID(cert.certificate, sshKeyType);

			if (key.key.join() == keyInfo.join()) {
				certToUse = cert;
				certToUseType = key.publicKeyType;
			}
		});
	});

	/*
	 * If no certificate is found, return an error
	 */
	if (!certToUse) {
		console.info("[cackeySSH] Unable to find a certificate to match the requested key:", keyInfo);