Outlook MCP Server

/**
 * Token management for Microsoft Graph API authentication
 */
const fs = require("fs");
const config = require("../config");

// Global variable to store tokens
let cachedTokens = null;

/**
 * Loads authentication tokens from the token file
 * @returns {object|null} - The loaded tokens or null if not available
 */
function loadTokenCache() {
	try {
		const tokenPath = config.AUTH_CONFIG.tokenStorePath;
		console.error(`[DEBUG] Attempting to load tokens from: ${tokenPath}`);
		console.error(`[DEBUG] HOME directory: ${process.env.HOME}`);
		console.error(`[DEBUG] Full resolved path: ${tokenPath}`);

		// Log file existence and details
		if (!fs.existsSync(tokenPath)) {
			console.error("[DEBUG] Token file does not exist");
			return null;
		}

		const stats = fs.statSync(tokenPath);
		console.error(`[DEBUG] Token file stats:
      Size: ${stats.size} bytes
      Created: ${stats.birthtime}
      Modified: ${stats.mtime}`);

		const tokenData = fs.readFileSync(tokenPath, "utf8");
		console.error("[DEBUG] Token file contents length:", tokenData.length);
		console.error(
			"[DEBUG] Token file first 200 characters:",
			tokenData.slice(0, 200),
		);

		try {
			const tokens = JSON.parse(tokenData);
			console.error("[DEBUG] Parsed tokens keys:", Object.keys(tokens));

			// Log each key's value to see what's present
			Object.keys(tokens).forEach((key) => {
				console.error(`[DEBUG] ${key}: ${typeof tokens[key]}`);
			});

			// Check for access token presence
			if (!tokens.access_token) {
				console.error("[DEBUG] No access_token found in tokens");
				return null;
			}

			// Check token expiration
			const now = Date.now();
			const expiresAt = tokens.expires_at || 0;

			console.error(`[DEBUG] Current time: ${now}`);
			console.error(`[DEBUG] Token expires at: ${expiresAt}`);

			if (now > expiresAt) {
				console.error("[DEBUG] Token has expired");
				return null;
			}

			// Update the cache
			cachedTokens = tokens;
			return tokens;
		} catch (parseError) {
			console.error("[DEBUG] Error parsing token JSON:", parseError);
			return null;
		}
	} catch (error) {
		console.error("[DEBUG] Error loading token cache:", error);
		return null;
	}
}

/**
 * Saves authentication tokens to the token file
 * @param {object} tokens - The tokens to save
 * @returns {boolean} - Whether the save was successful
 */
function saveTokenCache(tokens) {
	try {
		const tokenPath = config.AUTH_CONFIG.tokenStorePath;
		console.error(`Saving tokens to: ${tokenPath}`);

		fs.writeFileSync(tokenPath, JSON.stringify(tokens, null, 2));
		console.error("Tokens saved successfully");

		// Update the cache
		cachedTokens = tokens;
		return true;
	} catch (error) {
		console.error("Error saving token cache:", error);
		return false;
	}
}

/**
 * Gets the current access token, loading from cache if necessary
 * @returns {string|null} - The access token or null if not available
 */
function getAccessToken() {
	if (cachedTokens && cachedTokens.access_token) {
		return cachedTokens.access_token;
	}

	const tokens = loadTokenCache();
	return tokens ? tokens.access_token : null;
}

/**
 * Creates a test access token for use in test mode
 * @returns {object} - The test tokens
 */
function createTestTokens() {
	const testTokens = {
		access_token: "test_access_token_" + Date.now(),
		refresh_token: "test_refresh_token_" + Date.now(),
		expires_at: Date.now() + 3600 * 1000, // 1 hour
	};

	saveTokenCache(testTokens);
	return testTokens;
}

module.exports = {
	loadTokenCache,
	saveTokenCache,
	getAccessToken,
	createTestTokens,
};