// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using Microsoft.AspNetCore.Razor.Language.Intermediate;

namespace Microsoft.AspNetCore.Razor.Language.CodeGeneration
{
    public abstract class CodeRenderingContext
    {
        internal static readonly object NewLineString = "NewLineString";
        internal static readonly object SuppressUniqueIds = "SuppressUniqueIds";

        public abstract CodeWriter CodeWriter { get; }

        public abstract RazorDiagnosticCollection Diagnostics { get; }

        public abstract string DocumentKind { get; }

        public abstract ItemCollection Items { get; }

        public abstract IntermediateNodeWriter NodeWriter { get; }

        public abstract RazorCodeGenerationOptions Options { get; }

        public abstract RazorSourceDocument SourceDocument { get; }

        public abstract Scope CreateScope();

        public abstract Scope CreateScope(IntermediateNodeWriter writer);

        public abstract void EndScope();

        public abstract void RenderNode(IntermediateNode node);

        public abstract void RenderChildren(IntermediateNode node);

        public abstract void AddLineMappingFor(IntermediateNode node);

        public struct Scope : IDisposable
        {
            private readonly CodeRenderingContext _context;

            public Scope(CodeRenderingContext context)
            {
                if (context == null)
                {
                    throw new ArgumentNullException(nameof(context));
                }

                _context = context;
            }

            public void Dispose()
            {
                _context.EndScope();
            }
        }


        // All bits below here are temporary

        #region Temporary TagHelper bits

        internal TagHelperRenderingContext TagHelperRenderingContext { get; set; }

        internal TagHelperRenderingContextScope Push(TagHelperRenderingContext context)
        {
            if (context == null)
            {
                throw new ArgumentNullException(nameof(context));
            }

            var scope = new TagHelperRenderingContextScope(this, TagHelperRenderingContext);
            TagHelperRenderingContext = context;
            return scope;
        }

        internal struct TagHelperRenderingContextScope : IDisposable
        {
            private readonly CodeRenderingContext _context;
            private readonly TagHelperRenderingContext _renderingContext;

            public TagHelperRenderingContextScope(CodeRenderingContext context, TagHelperRenderingContext renderingContext)
            {
                if (context == null)
                {
                    throw new ArgumentNullException(nameof(context));
                }

                _context = context;
                _renderingContext = renderingContext;
            }

            public void Dispose()
            {
                _context.TagHelperRenderingContext = _renderingContext;
            }
        }

        #endregion
    }
}