using Grand.Business.Core.Interfaces.Common.Pdf;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Abstractions;
using Microsoft.AspNetCore.Mvc.ModelBinding;
using Microsoft.AspNetCore.Mvc.Razor;
using Microsoft.AspNetCore.Mvc.Rendering;
using Microsoft.AspNetCore.Mvc.ViewFeatures;
using Microsoft.AspNetCore.Routing;

namespace Grand.Web.Common.ViewRender
{
    /// <summary>
    /// Allow to get Razor page content as string
    /// </summary>
    public class ViewRenderService : IViewRenderService
    {
        private readonly IRazorViewEngine _razorViewEngine;
        private readonly ITempDataProvider _tempDataProvider;
        private readonly IServiceProvider _serviceProvider;


        public ViewRenderService(IRazorViewEngine razorViewEngine,
            ITempDataProvider tempDataProvider,
            IServiceProvider serviceProvider)
        {
            _razorViewEngine = razorViewEngine;
            _tempDataProvider = tempDataProvider;
            _serviceProvider = serviceProvider;
        }


        public async Task<string> RenderToStringAsync<TModel>(string viewPath, TModel model)
        {
            var httpContext = new DefaultHttpContext { RequestServices = _serviceProvider };
            var actionContext = new ActionContext(httpContext, new RouteData(), new ActionDescriptor());

            await using var sw = new StringWriter();
            var viewResult = _razorViewEngine.GetView(viewPath, viewPath, false);

            if (viewResult.View == null)
            {
                throw new ArgumentNullException($"{viewPath} does not match any available view");
            }

            var viewDictionary = new ViewDataDictionary(new EmptyModelMetadataProvider(), new ModelStateDictionary()) {
                Model = model
            };

            var viewContext = new ViewContext(
                actionContext,
                viewResult.View,
                viewDictionary,
                new TempDataDictionary(actionContext.HttpContext, _tempDataProvider),
                sw,
                new HtmlHelperOptions()
            );

            await viewResult.View.RenderAsync(viewContext);
            return sw.ToString();
        }
    }
}

