Introduction to Bellevue View Engine - Part 1

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Ope.Bellevue.Rendering;

namespace Ope.Bellevue.Renderers.General
{
    public class Text : INodeRenderer, IAttributeRenderer
    {
        public void RenderNode(RenderingInstruction parameters, DataContext data, ViewRenderingContext renderContext)
        {
            string text = data.GetValue(parameters["value"]);
            if (parameters["noEncoding"] == null || parameters["noEncoding"].Value != "true")
            {
                text = System.Web.HttpUtility.HtmlEncode(text);
            }
            renderContext.Write(text);
        }

        public void RenderAttribute(string attributeName, RenderingInstruction parameters, DataContext data, ViewRenderingContext renderContext)
        {
            // TODO: Think which one to use: the one from RenderAttribute method or from parameters.
            string attrName = data.GetValue(parameters["attr-name"]);
            string newText = data.GetValue(parameters["value"]);
            string text = data.GetValue(parameters["original-value"]);

            switch (parameters.Position)
            {
                case RelativePosition.ReplaceOuter:
                    renderContext.Output.Write(newText);
                    return;
                case RelativePosition.Append:
                    text += newText;
                    break;
                case RelativePosition.Insert:
                    text = newText + text;
                    break;
                case RelativePosition.InsertBefore:
                    renderContext.Output.Write(newText);
                    break;
                case RelativePosition.Default:
                case RelativePosition.ReplaceInner:
                    text = newText;
                    break;
            }
            
            renderContext.RenderAttr(attributeName, text);

            if (parameters.Position == RelativePosition.InsertAfter)
            {
                renderContext.Output.Write(newText);
            }
        }
    }

    public class TextFormat : INodeRenderer
    {
        public void RenderNode(RenderingInstruction parameters, DataContext data, ViewRenderingContext renderContext)
        {
            object valueToFormat = data.GetObject(parameters["value"]);
            string formatString = parameters["format-text"].Value;
            string text = System.Web.HttpUtility.HtmlEncode(string.Format(formatString, valueToFormat));
            renderContext.Write(text);
        }
    }

    public class TextReplace : INodeRenderer
    {
        public void RenderNode(RenderingInstruction parameters, DataContext data, ViewRenderingContext renderContext)
        {
            string newText = data.GetValue(parameters["value"]);
            string replaceText = data.GetValue(parameters["replace-text"]);
            string originalText = parameters["original-text"].Value;
            string text = System.Web.HttpUtility.HtmlEncode(originalText.Replace(replaceText, newText));
            renderContext.Write(text);
        }
    }

    public class Checked : IAttributeRenderer 
    {
        public void RenderAttribute(string attributeName, RenderingInstruction parameters, DataContext data, ViewRenderingContext renderContext)
        {
            if (data.GetBool(parameters["value"]))
            {
                renderContext.RenderAttr(attributeName, "checked");
            }
        }
    }

    public class ApplyTemplate : INodeRenderer
    {
        public void RenderNode(RenderingInstruction parameters, DataContext data, ViewRenderingContext renderContext)
        {
            var templateContainer = renderContext.Templates.GetTemplate(data.GetValue(parameters["template-id"]));
            if (templateContainer == null)
            {
                return;
            }
            var collection = data.GetEnumerable(parameters["value"]);
            if (collection == null)
            {
                // TODO: Is this an error or not? Warning?
                return;
            }

            var itemEnumerator = collection.GetEnumerator();
            int counter = -1;
            bool quit = false;
            while (!quit)
            {
                foreach (var templateElem in templateContainer)
                {
                    if (!itemEnumerator.MoveNext())
                    {
                        quit = true;
                        break;
                    }
                    counter++;
                    HtmlRenderer.RenderNode(templateElem, data.GetItemContext(itemEnumerator.Current, counter), renderContext);
                }
            }
        }
    }

    public class RenderControl : INodeRenderer
    {
        public void RenderNode(RenderingInstruction parameters, DataContext data, ViewRenderingContext renderContext)
        {
            string partialViewName = data.GetValue(parameters["value"]);

            System.Web.Mvc.ViewEngineResult result = System.Web.Mvc.ViewEngines.Engines.FindPartialView(renderContext.MvcViewContext, partialViewName);
            if (result.View == null)
            {
                StringBuilder locationsText = new StringBuilder();
                foreach (string location in result.SearchedLocations)
                {
                    locationsText.AppendLine();
                    locationsText.Append(location);
                }

                throw new InvalidOperationException(String.Format(
                    "The partial view '{0}' could not be found. The following locations were searched:{1}",
                    partialViewName, locationsText));
            }
            else
            {
                result.View.Render(renderContext.MvcViewContext, renderContext.Output);
            }
        }
    }
}