//-----------------------------------------------------------------------
// <copyright file="SessionConfiguration.cs" company="Microsoft Corporation">
//     Copyright (C) 2011 Microsoft Corporation
// </copyright>
//-----------------------------------------------------------------------

namespace Microsoft.Samples.Management.OData.RoleBasedPlugins
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Management.Automation;
    using System.Management.Automation.Remoting;
    using System.Management.Automation.Runspaces;

    /// <summary>
    /// Custom Session configuration implementation
    /// </summary>
    public class SessionConfiguration : PSSessionConfiguration
    {
        /// <summary>
        /// Gets application private data
        /// </summary>
        /// <param name="senderInfo">Sender information</param>
        /// <returns>Always returns null</returns>
        public override PSPrimitiveDictionary GetApplicationPrivateData(PSSenderInfo senderInfo)
        {
            return null;
        }

        /// <summary>
        /// Gets custom initial session state
        /// It relies on the RBAC system to give list of commands allowed for a user
        /// and creates Initial Session state from that
        /// </summary>
        /// <param name="senderInfo">Sender information</param>
        /// <returns>Custom initial Session state</returns>
        public override InitialSessionState GetInitialSessionState(PSSenderInfo senderInfo)
        {
            if (senderInfo == null)
            {
                throw new ArgumentNullException("senderInfo");
            }

            if (senderInfo.UserInfo == null)
            {
                throw new ArgumentException("senderInfo.UserInfo is null");
            }

            InitialSessionState initialSessionState = InitialSessionState.CreateDefault();
            foreach (SessionStateCommandEntry command in initialSessionState.Commands)
            {
                command.Visibility = SessionStateEntryVisibility.Private;
            }

            List<string> scripts = RbacSystem.Current.GetScripts(senderInfo.UserInfo);
            foreach (string script in scripts)
            {
                initialSessionState.Commands.Add(new SessionStateScriptEntry(script));
            }

            List<string> modules = RbacSystem.Current.GetModules(senderInfo.UserInfo);
            if (modules.Count > 0)
            {
                initialSessionState.ImportPSModule(modules.ToArray());
            }

            // enable execution of scripts in this process
            System.Environment.SetEnvironmentVariable("PSExecutionPolicyPreference", "unrestricted");

            List<string> cmdletsFromRbac = RbacSystem.Current.GetCmdlets(senderInfo.UserInfo);

            // Add all commands from Rbac system to Initial Session State commands
            foreach (string cmdlet in cmdletsFromRbac)
            {
                SessionStateCommandEntry cmdletFromRbac = initialSessionState.Commands.FirstOrDefault(item => string.Equals(item.Name, cmdlet, StringComparison.OrdinalIgnoreCase));
                if (cmdletFromRbac == null)
                {
                    throw new ArgumentException("Command not found in InitialSessionState " + cmdlet);
                }

                cmdletFromRbac.Visibility = SessionStateEntryVisibility.Public;
            }

            return initialSessionState;
        }
    }
}