//  Copyright 2016 Google Inc. All Rights Reserved.
//
//  Licensed under the Apache License, Version 2.0 (the "License");
//  you may not use this file except in compliance with the License.
//  You may obtain a copy of the License at
//
//  http://www.apache.org/licenses/LICENSE-2.0
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//  See the License for the specific language governing permissions and
//  limitations under the License.

using NtApiDotNet;
using System.Management.Automation;

namespace NtObjectManager.Cmdlets.Object
{
    /// <summary>
    /// <para type="synopsis">Unloads a registry hive.</para>
    /// <para type="description">This cmdlet unloads a registry hive in the registry namespace.</para>
    /// </summary>
    /// <example>
    ///   <code>Remove-NtKeyHive \Registry\Machine\ABC</code>
    ///   <para>Unload the \Registry\Machine\ABC hive.</para>
    /// </example>
    /// <example>
    ///   <code>Remove-NtKey \Registry\Machine\ABC -Flags ForceUnload</code>
    ///   <para>Unload the \Registry\Machine\ABC hive, forcing the unload if necessary.</para>
    /// </example>
    [Cmdlet(VerbsCommon.Remove, "NtKeyHive")]
    public sealed class RemoveKeyHiveCmdlet : NtObjectBaseCmdlet
    {
        /// <summary>
        /// Determine if the cmdlet can create objects.
        /// </summary>
        /// <returns>True if objects can be created.</returns>
        protected override bool CanCreateDirectories()
        {
            return false;
        }

        /// <summary>
        /// <para type="description">The NT object manager path to the object to use.</para>
        /// </summary>
        [Parameter(Position = 0, Mandatory = true)]
        public override string Path { get; set; }

        /// <summary>
        /// Virtual method to return the value of the Path variable.
        /// </summary>
        /// <returns>The object path.</returns>
        protected override string ResolvePath()
        {
            if (Win32Path)
            {
                return NtKeyUtils.Win32KeyNameToNt(Path);
            }
            else
            {
                return Path;
            }
        }

        /// <summary>
        /// <para type="description">Specifes the flags for unloading the hive.</para>
        /// </summary>
        [Parameter]
        public UnloadKeyFlags Flags { get; set; }

        /// <summary>
        /// Method to create an object from a set of object attributes.
        /// </summary>
        /// <param name="obj_attributes">The object attributes to create/open from.</param>
        /// <returns>Always null.</returns>
        protected override object CreateObject(ObjectAttributes obj_attributes)
        {
            NtKey.UnloadKey(obj_attributes, Flags, true);
            return null;
        }
    }
}
