using System;
using System.Collections.Specialized;
using MailBee;
using MailBee.ImapMail;
using DotNetOpenAuth.OAuth2;

class Sample
{
	static string GetAccessToken(string clientID, string clientSecret, string key)
	{
		UserAgentClient consumer;
		IAuthorizationState grantedAccess;

		// Second: Fetch Access Token
		StringDictionary parameters2 = new StringDictionary();
		parameters2.Add(OAuth2.RedirectUriKey, "urn:ietf:wg:oauth:2.0:oob");

		string uri = "https://accounts.google.com/o/oauth2/token";

		AuthorizationServerDescription server = new AuthorizationServerDescription();
		server.TokenEndpoint = new Uri(uri);
		server.ProtocolVersion = ProtocolVersion.V20;

		consumer = new UserAgentClient(server, clientID, clientSecret);

		consumer.ClientCredentialApplicator = ClientCredentialApplicator.PostParameter(clientSecret);

		IAuthorizationState authorizationState = new AuthorizationState(null);

		if (parameters2.ContainsKey(OAuth2.RedirectUriKey))
		{
			authorizationState.Callback = new Uri(parameters2[OAuth2.RedirectUriKey]);
		}

		// Build a generic URL containing the auth code.
		// This is done here as we cannot modify the DotNetOpenAuth library 
		// and the underlying method only allows parsing an URL as a method 
		// of retrieving the AuthorizationState.
		string url = "http://example.com/?code=" + key;

		try
		{
			grantedAccess = consumer.ProcessUserAuthorization(new Uri(url), authorizationState);
		}
		catch (DotNetOpenAuth.Messaging.ProtocolException e)
		{
			Console.WriteLine(e.Message);
			return null;
		}

		return grantedAccess.AccessToken;
	}

	static void Main(string[] args)
	{
		MailBee.Global.LicenseKey = "MN700-...";

		// Set these as described at https://code.google.com/p/google-api-dotnet-client/wiki/OAuth2
		string clientID = "1234567890.apps.googleusercontent.com";
		string clientSecret = "1a2b3c4d5e6f7h";
		string userEmail = "john.doe@gmail.com";

		OAuth2 myOAuth2 = new OAuth2(clientID, clientSecret);

		StringDictionary parameters1 = new StringDictionary();
		parameters1.Add(OAuth2.Scope, "https://mail.google.com/");
		parameters1.Add(OAuth2.RedirectUriKey, "urn:ietf:wg:oauth:2.0:oob");
		parameters1.Add(OAuth2.ResponseTypeKey, "code");

		// First: Redirect to Authorization and Fire up the browser
		System.Diagnostics.Process.Start(
		 myOAuth2.AuthorizeToken("https://accounts.google.com/o/oauth2/auth", parameters1));

		Console.Write("Please enter the key: ");
		string key = Console.ReadLine().Trim();

		// Second: Fetch Access Token
		string accessToken = GetAccessToken(clientID, clientSecret, key);
		if (accessToken == null)
		{
			return;
		}

		// Get XOAuth key for IMAP.
		string imapXOAuthKey = myOAuth2.GetXOAuthKey(userEmail, accessToken);

		Imap imp = new Imap();

		// In the log, you can find the actual search queries sent to the server.
		imp.Log.Filename = "C:\\Temp\\log.txt";
		imp.Log.Enabled = true;
		imp.Log.Clear();

		imp.Connect("imap.gmail.com", 993);
		imp.Login(null, imapXOAuthKey, AuthenticationMethods.SaslOAuth2, AuthenticationOptions.None, null);
		imp.SelectFolder("INBOX");

		// Processing of INBOX emails here.
		//...

		imp.Disconnect();
	}
}