/// <summary>
        ///     This is called when the user is adding (or updating) a package source
        ///     If this PROVIDER doesn't support user-defined package sources, remove this method.
        /// </summary>
        /// <param name="name">
        ///     The name of the package source. If this parameter is null or empty the PROVIDER should use the
        ///     location as the name (if the PROVIDER actually stores names of package sources)
        /// </param>
        /// <param name="location">
        ///     The location (ie, directory, URL, etc) of the package source. If this is null or empty, the
        ///     PROVIDER should use the name as the location (if valid)
        /// </param>
        /// <param name="trusted">
        ///     A boolean indicating that the user trusts this package source. Packages returned from this source
        ///     should be marked as 'trusted'
        /// </param>
        /// <param name="request">
        ///     An object passed in from the CORE that contains functions that can be used to interact with the
        ///     CORE and HOST
        /// </param>
        public void AddPackageSource(string name, string location, bool trusted, ChocolateyRequest request)
        {
            // Nice-to-have put a debug message in that tells what's going on.
            request.Debug("Calling '{0}::AddPackageSource' '{1}','{2}','{3}'", PackageProviderName, name, location,
                trusted);

            // if they didn't pass in a name, use the location as a name. (if you support that kind of thing)
            name = string.IsNullOrEmpty(name) ? location : name;

            // let's make sure that they've given us everything we need.
            if (string.IsNullOrEmpty(name)) {
                request.Error(ErrorCategory.InvalidArgument, Constants.Parameters.Name,
                    Constants.Messages.MissingRequiredParameter, Constants.Parameters.Name);
                // we're done here.
                return;
            }

            if (string.IsNullOrEmpty(location)) {
                request.Error(ErrorCategory.InvalidArgument, Constants.Parameters.Location,
                    Constants.Messages.MissingRequiredParameter, Constants.Parameters.Location);
                // we're done here.
                return;
            }

            // if this is supposed to be an update, there will be a dynamic parameter set for IsUpdatePackageSource
            var isUpdate = request.GetOptionValue(Constants.Parameters.IsUpdate).IsTrue();

            // if your source supports credentials you get get them too:
            // string username =request.Username;
            // SecureString password = request.Password;
            // feel free to send back an error here if your provider requires credentials for package sources.

            // check first that we're not clobbering an existing source, unless this is an update

            var src = request.FindRegisteredSource(name);

            if (src != null && !isUpdate) {
                // tell the user that there's one here already
                request.Error(ErrorCategory.InvalidArgument, name ?? location, Constants.Messages.PackageSourceExists,
                    name ?? location);
                // we're done here.
                return;
            }

            // conversely, if it didn't find one, and it is an update, that's bad too:
            if (src == null && isUpdate) {
                // you can't find that package source? Tell that to the user
                request.Error(ErrorCategory.ObjectNotFound, name ?? location, Constants.Messages.UnableToResolveSource,
                    name ?? location);
                // we're done here.
                return;
            }

            // ok, we know that we're ok to save this source
            // next we check if the location is valid (if we support that kind of thing)

            var validated = false;

            if (!request.SkipValidate) {
                // the user has not opted to skip validating the package source location, so check that it's valid (talk to the url, or check if it's a valid directory, etc)
                // todo: insert code to check if the source is valid

                validated = request.ValidateSourceLocation(location);

                if (!validated) {
                    request.Error(ErrorCategory.InvalidData, name ?? location, Constants.Messages.SourceLocationNotValid,
                        location);
                    // we're done here.
                    return;
                }

                // we passed validation!
            }

            // it's good to check just before you actaully write something to see if the user has cancelled the operation
            if (request.IsCanceled) {
                return;
            }

            // looking good -- store the package source
            // todo: create the package source (and store it whereever you store it)

            request.Verbose("Storing package source {0}", name);

            // actually yielded by the implementation.
            request.AddPackageSource(name, location, trusted, validated);

            // and, before you go, Yield the package source back to the caller.
            if (!request.YieldPackageSource(name, location, trusted, true /*since we just registered it*/, validated)) {
                // always check the return value of a yield, since if it returns false, you don't keep returning data
                // this can happen if they have cancelled the operation.
            }
            // all done!
        }
        /// <summary>
        ///     This is called when the user is adding (or updating) a package source
        ///     If this PROVIDER doesn't support user-defined package sources, remove this method.
        /// </summary>
        /// <param name="name">
        ///     The name of the package source. If this parameter is null or empty the PROVIDER should use the
        ///     location as the name (if the PROVIDER actually stores names of package sources)
        /// </param>
        /// <param name="location">
        ///     The location (ie, directory, URL, etc) of the package source. If this is null or empty, the
        ///     PROVIDER should use the name as the location (if valid)
        /// </param>
        /// <param name="trusted">
        ///     A boolean indicating that the user trusts this package source. Packages returned from this source
        ///     should be marked as 'trusted'
        /// </param>
        /// <param name="request">
        ///     An object passed in from the CORE that contains functions that can be used to interact with the
        ///     CORE and HOST
        /// </param>
        public void AddPackageSource(string name, string location, bool trusted, ChocolateyRequest request)
        {
            // Nice-to-have put a debug message in that tells what's going on.
            request.Debug("Calling '{0}::AddPackageSource' '{1}','{2}','{3}'", PackageProviderName, name, location,
                          trusted);

            // if they didn't pass in a name, use the location as a name. (if you support that kind of thing)
            name = string.IsNullOrEmpty(name) ? location : name;

            // let's make sure that they've given us everything we need.
            if (string.IsNullOrEmpty(name))
            {
                request.Error(ErrorCategory.InvalidArgument, Constants.Parameters.Name,
                              Constants.Messages.MissingRequiredParameter, Constants.Parameters.Name);
                // we're done here.
                return;
            }

            if (string.IsNullOrEmpty(location))
            {
                request.Error(ErrorCategory.InvalidArgument, Constants.Parameters.Location,
                              Constants.Messages.MissingRequiredParameter, Constants.Parameters.Location);
                // we're done here.
                return;
            }

            // if this is supposed to be an update, there will be a dynamic parameter set for IsUpdatePackageSource
            var isUpdate = request.GetOptionValue(Constants.Parameters.IsUpdate).IsTrue();

            // if your source supports credentials you get get them too:
            // string username =request.Username;
            // SecureString password = request.Password;
            // feel free to send back an error here if your provider requires credentials for package sources.

            // check first that we're not clobbering an existing source, unless this is an update

            var src = request.FindRegisteredSource(name);

            if (src != null && !isUpdate)
            {
                // tell the user that there's one here already
                request.Error(ErrorCategory.InvalidArgument, name ?? location, Constants.Messages.PackageSourceExists,
                              name ?? location);
                // we're done here.
                return;
            }

            // conversely, if it didn't find one, and it is an update, that's bad too:
            if (src == null && isUpdate)
            {
                // you can't find that package source? Tell that to the user
                request.Error(ErrorCategory.ObjectNotFound, name ?? location, Constants.Messages.UnableToResolveSource,
                              name ?? location);
                // we're done here.
                return;
            }

            // ok, we know that we're ok to save this source
            // next we check if the location is valid (if we support that kind of thing)

            var validated = false;

            if (!request.SkipValidate)
            {
                // the user has not opted to skip validating the package source location, so check that it's valid (talk to the url, or check if it's a valid directory, etc)
                // todo: insert code to check if the source is valid

                validated = request.ValidateSourceLocation(location);

                if (!validated)
                {
                    request.Error(ErrorCategory.InvalidData, name ?? location, Constants.Messages.SourceLocationNotValid,
                                  location);
                    // we're done here.
                    return;
                }

                // we passed validation!
            }

            // it's good to check just before you actaully write something to see if the user has cancelled the operation
            if (request.IsCanceled)
            {
                return;
            }

            // looking good -- store the package source
            // todo: create the package source (and store it whereever you store it)

            request.Verbose("Storing package source {0}", name);

            // actually yielded by the implementation.
            request.AddPackageSource(name, location, trusted, validated);

            // and, before you go, Yield the package source back to the caller.
            if (!request.YieldPackageSource(name, location, trusted, true /*since we just registered it*/, validated))
            {
                // always check the return value of a yield, since if it returns false, you don't keep returning data
                // this can happen if they have cancelled the operation.
            }
            // all done!
        }