laatzen/LaaProductionWeb/LaaProduction.Http/URIHelper.cs

namespace LaaProduction.Http
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Reflection;
    using System.Web;

    public class URIHelper
    {
        private readonly string path;
        private readonly IDictionary<string, string> query;

        public URIHelper(string value)
        {
            this.query = new Dictionary<string, string>();
            this.path = this.ParsePathAndQuery(value);
        }

        public URIHelper AddQuery(object query)
        {
            if (query != null)
            {
                if (query is string queryString)
                {
                    var queryTokens = queryString.Split(new[] { '&' }, StringSplitOptions.RemoveEmptyEntries);

                    foreach (var token in queryTokens)
                    {
                        var kvpTokens = token.Split(new[] { '=' }, StringSplitOptions.RemoveEmptyEntries);

                        if (kvpTokens.Length == 2)
                        {
                            this.query[kvpTokens[0]] = kvpTokens[1];
                        }
                    }
                }
                else if (query is IDictionary<string, string> parameters)
                {
                    foreach (var kvp in parameters)
                    {
                        this.query[kvp.Key] = kvp.Value;
                    }
                }
                else
                {
                    var properties = query
                        .GetType()
                        .GetProperties(BindingFlags.Public | BindingFlags.Instance);

                    foreach (var property in properties)
                    {
                        var key = property.Name.ToLower();
                        var value = property.GetValue(query);

                        this.query[key] = HttpUtility.UrlEncode($"{value}");
                    }
                }
            }

            return this;
        }

        public override string ToString()
        {
            if (this.query.Count == 0)
            {
                return this.path;
            }

            return $"{this.path}?{string.Join("&", this.query.Select(x => $"{x.Key}={x.Value}"))}";
        }

        private string ParsePathAndQuery(String value)
        {
            if (string.IsNullOrWhiteSpace(value))
            {
                return "/";
            }

            var routeTokens = value.Split(new[] { '?' }, StringSplitOptions.RemoveEmptyEntries);

            if (routeTokens.Length >= 2)
            {
                var queryTokens = routeTokens[1].Split(new[] { '&' }, StringSplitOptions.RemoveEmptyEntries);

                foreach (var token in queryTokens)
                {
                    var kvpTokens = token.Split(new[] { '=' }, StringSplitOptions.RemoveEmptyEntries);

                    if (kvpTokens.Length == 2)
                    {
                        this.query[kvpTokens[0]] = kvpTokens[1];
                    }
                }
            }

            if (routeTokens.Length >= 1)
            {
                return routeTokens[0];
            }

            return "/";
        }
    }
}