// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
///////////////////////////////////////////////////////////////////////////////
//
// Update application manifest for browser-hosted application.
//
///////////////////////////////////////////////////////////////////////////////
 
using System;
using System.Runtime.InteropServices;
using Microsoft.Build.Framework;
using Microsoft.Build.Utilities;
using System.Xml;
 
using MS.Utility;
using MS.Internal.Tasks;
 
namespace Microsoft.Build.Tasks.Windows
{
    #region Manifest Creator Task class
 
    /// <summary>
    /// Class of UpdateManifestForBrowserApplication
    /// </summary>
    public sealed class UpdateManifestForBrowserApplication : Task
    {
 
        //------------------------------------------------------
        //
        //  Constructors
        //
        //------------------------------------------------------
 
        #region Constructors
        /// <summary>
        /// Constructors
        /// </summary>
        public UpdateManifestForBrowserApplication()
            : base(SR.SharedResourceManager)
        {
        }
 
        #endregion Constructors
 
        //------------------------------------------------------
        //
        //  Public Methods
        //
        //------------------------------------------------------
 
        #region Public Methods
 
        /// <summary>
        /// Add hostInBrowser element node to the application manifest file.
        /// </summary>
        /// <returns></returns>
        public override bool Execute()
        {
            bool successful = true;
            TaskHelper.DisplayLogo(Log, nameof(UpdateManifestForBrowserApplication));
 
            if (!HostInBrowser)
            {
                // HostInBrowser is not true, don't modify the manifest.
                // Stop here.
                return successful;
            }
 
            try
            {
                string appManifestFile = ApplicationManifest[0].ItemSpec;
                XmlDocument manifestDocument;
 
                XmlTextReader manifestReader = null;
                XmlTextWriter manifestWriter = null;
 
                //Read the manifest
                try
                {
                    manifestReader = new XmlTextReader(appManifestFile);
                    manifestDocument = new XmlDocument();
                    manifestDocument.Load(manifestReader);
                }
                finally
                {
                    // Close the manifest reader
                    manifestReader?.Close();
                }
 
                // NOTE:
                //
                // manifestReader must be closed before the manfiestWriter can
                // update the document on the same manifest file.
                //
 
                //Get to entryPoint XML
                XmlNodeList entryPointList = manifestDocument.GetElementsByTagName(c_entryPoint);
                XmlNode entryPoint = entryPointList[0];
 
                //Create element node for browser entry point
                XmlElement hostInBrowser;
                hostInBrowser = manifestDocument.CreateElement(c_hostInBrowser, c_asmv3);
 
                // Append HostInBrowser node to the end of list of children of entryPoint.
                entryPoint.AppendChild(hostInBrowser);
 
                // Update the manifest file.
                try
                {
                    manifestWriter = new XmlTextWriter(appManifestFile, System.Text.Encoding.UTF8)
                    {
                        Formatting = Formatting.Indented,
                        Indentation = 4
                    };
                    manifestDocument.WriteTo(manifestWriter);
                }
                finally
                {
                    // Close the manifest writer
                    manifestWriter?.Close();
                }
 
            }
            catch (Exception e)
            {
                if (e is NullReferenceException || e is SEHException)
                {
                    throw;
                }
                else
                {
                    Log.LogErrorFromException(e);
                    successful = false;
                }
            }
            catch   // Non-cls compliant errors
            {
                Log.LogErrorWithCodeFromResources(nameof(SR.NonClsError));
                successful = false;
            }
 
            return successful;
        }
 
        #endregion Public Methods
 
        //------------------------------------------------------
        //
        //  Public Properties
        //
        //------------------------------------------------------
 
        #region Public Properties
 
        /// <summary>
        /// Host In Browser
        /// </summary>
        /// <value></value>
        [Required]
        public bool HostInBrowser
        {
            get { return _hostInBrowser; }
            set
            {
                _hostInBrowser = value;
            }
        }
 
        /// <summary>
        /// Application Manifest File
        /// </summary>
        /// <value></value>
        [Required]
        public ITaskItem[] ApplicationManifest
        {
            get { return _applicationmanifest; }
            set { _applicationmanifest = value; }
        }
 
        #endregion Public Properties
 
        //------------------------------------------------------
        //
        //  Private Fields
        //
        //------------------------------------------------------
 
        #region Private Fields
 
        private ITaskItem[] _applicationmanifest;
        private bool        _hostInBrowser = false;
 
        //
        // Put some predefined element or attribute name in below
        // const strings.
        //
        private const string c_entryPoint = "entryPoint";
        private const string c_hostInBrowser ="hostInBrowser";
        private const string c_asmv3= "urn:schemas-microsoft-com:asm.v3";
 
        #endregion Private Fields
 
    }
 
    #endregion Manifest Creator Task class
 
}