/* ****************************************************************************

 *

 * Copyright (c) Microsoft Corporation. 

 *

 * This source code is subject to terms and conditions of the Apache License, Version 2.0. A 

 * copy of the license can be found in the License.html file at the root of this distribution. If 

 * you cannot locate the Apache License, Version 2.0, please send an email to 

 * ironpy@microsoft.com. By using this source code in any fashion, you are agreeing to be bound 

 * by the terms of the Apache License, Version 2.0.

 *

 * You must not remove this notice, or any other, from this software.

 *

 * ***************************************************************************/



using System.Text;

using Microsoft.Scripting;

using Microsoft.Scripting.Hosting;

using Microsoft.Scripting.Hosting.Providers;

using Microsoft.VisualStudio.Text;



namespace Microsoft.IronStudio.Core {

    internal class SnapshotMultipleSpanTextContentProvider : TextContentProvider, ISnapshotTextContentProvider {

        private readonly NormalizedSnapshotSpanCollection _spans;



        internal SnapshotMultipleSpanTextContentProvider(NormalizedSnapshotSpanCollection spans) {

            _spans = spans;

        }



        internal static SourceUnit Make(ScriptEngine engine, NormalizedSnapshotSpanCollection spans) {

            return Make(engine, spans, "None");

        }



        internal static SourceUnit Make(ScriptEngine engine, NormalizedSnapshotSpanCollection spans, string path) {

            var textContent = new SnapshotMultipleSpanTextContentProvider(spans);

            var languageContext = HostingHelpers.GetLanguageContext(engine);

            return new SourceUnit(languageContext, textContent, path, SourceCodeKind.File);

        }



        #region TextContentProvider



        public override SourceCodeReader GetReader() {

            return new SourceCodeReader(new SnapshotMultipleSpanSourceCodeReader(_spans), Encoding.Default);

        }



        #endregion



        #region ISnapshotTextContentProvider



        public ITextSnapshot Snapshot {

            get {

                if (_spans.Count > 0) {

                    return _spans[0].Snapshot;

                }

                return null;

            }

        }



        #endregion

    }

}