// 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.Text;
using Microsoft.AspNetCore.Razor.Language.Intermediate;
using Xunit;

namespace Microsoft.AspNetCore.Blazor.Razor
{
    internal static class NodeAssert
    {
        public static HtmlAttributeIntermediateNode Attribute(IntermediateNode node, string attributeName, string attributeValue)
        {
            Assert.NotNull(node);

            var attributeNode = Assert.IsType<HtmlAttributeIntermediateNode>(node);
            Assert.Equal(attributeName, attributeNode.AttributeName);

            var attributeValueNode = Assert.IsType<HtmlAttributeValueIntermediateNode>(Assert.Single(attributeNode.Children));
            var actual = new StringBuilder();
            for (var i = 0; i < attributeValueNode.Children.Count; i++)
            {
                var token = Assert.IsType<IntermediateToken>(attributeValueNode.Children[i]);
                Assert.Equal(TokenKind.Html, token.Kind);
                actual.Append(token.Content);
            }

            Assert.Equal(attributeValue, actual.ToString());

            return attributeNode;
        }

        public static HtmlAttributeIntermediateNode Attribute(IntermediateNodeCollection nodes, string attributeName, string attributeValue)
        {
            Assert.NotNull(nodes);
            return Attribute(Assert.Single(nodes), attributeName, attributeValue);
        }

        public static HtmlContentIntermediateNode Content(IntermediateNode node, string content, bool trim = true)
        {
            Assert.NotNull(node);

            var contentNode = Assert.IsType<HtmlContentIntermediateNode>(node);

            var actual = new StringBuilder();
            for (var i = 0; i < contentNode.Children.Count; i++)
            {
                var token = Assert.IsType<IntermediateToken>(contentNode.Children[i]);
                Assert.Equal(TokenKind.Html, token.Kind);
                actual.Append(token.Content);
            }

            Assert.Equal(content, trim ? actual.ToString().Trim() : actual.ToString());
            return contentNode;
        }

        public static HtmlContentIntermediateNode Content(IntermediateNodeCollection nodes, string content, bool trim = true)
        {
            Assert.NotNull(nodes);
            return Content(Assert.Single(nodes), content, trim);
        }

        public static HtmlAttributeIntermediateNode CSharpAttribute(IntermediateNode node, string attributeName, string attributeValue)
        {
            Assert.NotNull(node);

            var attributeNode = Assert.IsType<HtmlAttributeIntermediateNode>(node);
            Assert.Equal(attributeName, attributeNode.AttributeName);

            var attributeValueNode = Assert.IsType<CSharpExpressionAttributeValueIntermediateNode>(Assert.Single(attributeNode.Children));
            var actual = new StringBuilder();
            for (var i = 0; i < attributeValueNode.Children.Count; i++)
            {
                var token = Assert.IsType<IntermediateToken>(attributeValueNode.Children[i]);
                Assert.Equal(TokenKind.CSharp, token.Kind);
                actual.Append(token.Content);
            }

            Assert.Equal(attributeValue, actual.ToString());

            return attributeNode;
        }

        public static HtmlAttributeIntermediateNode CSharpAttribute(IntermediateNodeCollection nodes, string attributeName, string attributeValue)
        {
            Assert.NotNull(nodes);
            return Attribute(Assert.Single(nodes), attributeName, attributeValue);
        }

        public static HtmlElementIntermediateNode Element(IntermediateNode node, string tagName)
        {
            Assert.NotNull(node);

            var elementNode = Assert.IsType<HtmlElementIntermediateNode>(node);
            Assert.Equal(tagName, elementNode.TagName);
            return elementNode;
        }

        public static HtmlElementIntermediateNode Element(IntermediateNodeCollection nodes, string tagName)
        {
            Assert.NotNull(nodes);
            return Element(Assert.Single(nodes), tagName);
        }

        public static HtmlContentIntermediateNode Whitespace(IntermediateNode node)
        {
            Assert.NotNull(node);

            var contentNode = Assert.IsType<HtmlContentIntermediateNode>(node);
            for (var i = 0; i < contentNode.Children.Count; i++)
            {
                var token = Assert.IsType<IntermediateToken>(contentNode.Children[i]);
                Assert.Equal(TokenKind.Html, token.Kind);
                Assert.True(string.IsNullOrWhiteSpace(token.Content));
            }

            return contentNode;
        }

        public static HtmlContentIntermediateNode Whitespace(IntermediateNodeCollection nodes)
        {
            Assert.NotNull(nodes);
            return Whitespace(Assert.Single(nodes));
        }
    }
}