QueryService.cs

using System;
using System.Linq;
using Collections.API.Helpers;
using Collections.API.Services.Interfaces;
using MongoDB.Driver;

namespace Collections.API.Services
{
    /// <summary>
    /// Service for building queries for the MongoDb API
    /// </summary>
    /// <seealso cref="Collections.API.Services.Interfaces.IQueryService" />
    public class QueryService : IQueryService
    {
        /// <summary>
        /// Builds the query.
        /// </summary>
        /// <typeparam name="TInterface">The interface type</typeparam>
        /// <typeparam name="TModel">The model type</typeparam>
        /// <returns></returns>
        public FilterDefinition<TInterface> BuildQuery<TInterface, TModel>() where TModel : class, TInterface, new()
        {
            return null;
        }

        /// <summary>
        /// Builds the query.
        /// </summary>
        /// <typeparam name="TInterface">The interface type</typeparam>
        /// <typeparam name="TModel">The model type</typeparam>
        /// <param name="searchModel">The search model</param>
        /// <returns></returns>
        public FilterDefinition<TInterface> BuildQuery<TInterface, TModel>(TModel searchModel) where TModel : class, TInterface, new()
        {
            var includedFields = searchModel.ToValueDictionary();

            var builder = Builders<TInterface>.Filter;

            var incFilter = builder.Empty;

            foreach (var incField in includedFields.ToList())
            {
                Type valueType = incField.Value.GetType();

                if (valueType == typeof(DateTime))
                {
                    var startDate = new DateTime(((DateTime)incField.Value).Year, 1, 1);
                    var endDate = new DateTime(startDate.AddYears(1).Year, 1, 1);

                    var test = builder.Gte(incField.Key, startDate);

                    incFilter |= builder.Gte(incField.Key, startDate) & builder.Lt(incField.Key, endDate);
                }

                if (incField.Key.Contains("["))
                {
                    var newKey = incField.Key.Remove(incField.Key.Length - 3);

                    incFilter |= builder.All(newKey, new[] { incField.Value });
                }

                else
                {
                    incFilter |= builder.Eq(incField.Key, incField.Value);
                }
            }

            return incFilter;
        }
    }
}