using System;
using System.Collections.Generic;
using System.Linq;
using Sieve.Models;
using Sieve.Services;
using SieveUnitTests.Entities;
using SieveUnitTests.Services;
using Xunit;

namespace SieveUnitTests
{
    public class StringFilterNullTests
    {
        private readonly IQueryable<Comment> _comments;
        private readonly SieveProcessor _processor;

        public StringFilterNullTests()
        {
            _processor = new SieveProcessor(new SieveOptionsAccessor());

            _comments = new List<Comment>
            {
                new Comment
                {
                    Id = 0,
                    DateCreated = DateTimeOffset.UtcNow,
                    Text = "This text contains null somewhere in the middle of a string",
                    Author = "Dog",
                },
                new Comment
                {
                    Id = 1,
                    DateCreated = DateTimeOffset.UtcNow, 
                    Text = "null is here in the text",
                    Author = "Cat",
                },
                new Comment
                {
                    Id = 2, 
                    DateCreated = DateTimeOffset.UtcNow, 
                    Text = "Regular comment without n*ll.",
                    Author = "Mouse",
                },
                new Comment
                {
                    Id = 100, 
                    DateCreated = DateTimeOffset.UtcNow, 
                    Text = null,
                    Author = "null",
                },
            }.AsQueryable();
        }

        [Fact]
        public void Filter_Equals_Null()
        {
            var model = new SieveModel {Filters = "Text==null"};

            var result = _processor.Apply(model, _comments);

            Assert.Equal(100, result.Single().Id);
        }

        [Fact]
        public void Filter_NotEquals_Null()
        {
            var model = new SieveModel {Filters = "Text!=null"};

            var result = _processor.Apply(model, _comments);

            Assert.Equal(new[] {0, 1, 2}, result.Select(p => p.Id));
        }

        [Theory]
        [InlineData("Text@=null")]
        [InlineData("Text@=*null")]
        [InlineData("Text@=*NULL")]
        [InlineData("Text@=*NulL")]
        [InlineData("Text@=*null|text")]
        public void Filter_Contains_NullString(string filter)
        {
            var model = new SieveModel {Filters = filter};

            var result = _processor.Apply(model, _comments);

            Assert.Equal(new[] {0, 1}, result.Select(p => p.Id));
        }
        
        [Theory]
        [InlineData("Text|Author==null", 100)]
        [InlineData("Text|Author@=null", 0, 1, 100)]
        [InlineData("Text|Author@=*null", 0, 1, 100)]
        [InlineData("Text|Author_=null", 1, 100)]
        [InlineData("Text|Author_=*null", 1, 100)]
        public void MultiFilter_Contains_NullString(string filter, params int[] expectedIds)
        {
            var model = new SieveModel {Filters = filter};

            var result = _processor.Apply(model, _comments);

            Assert.Equal(expectedIds, result.Select(p => p.Id));
        }

        [Theory]
        [InlineData("Text_=null")]
        [InlineData("Text_=*null")]
        [InlineData("Text_=*NULL")]
        [InlineData("Text_=*NulL")]
        [InlineData("Text_=*null|text")]
        public void Filter_StartsWith_NullString(string filter)
        {
            var model = new SieveModel {Filters = filter};

            var result = _processor.Apply(model, _comments);

            Assert.Equal(new[] {1}, result.Select(p => p.Id));
        }

        [Theory]
        [InlineData("Text!@=null")]
        [InlineData("Text!@=*null")]
        [InlineData("Text!@=*NULL")]
        [InlineData("Text!@=*NulL")]
        [InlineData("Text!@=*null|text")]
        public void Filter_DoesNotContain_NullString(string filter)
        {
            var model = new SieveModel {Filters = filter};

            var result = _processor.Apply(model, _comments);

            Assert.Equal(new[] {2}, result.Select(p => p.Id));
        }

        [Theory]
        [InlineData("Text!_=null")]
        [InlineData("Text!_=*null")]
        [InlineData("Text!_=*NULL")]
        [InlineData("Text!_=*NulL")]
        public void Filter_DoesNotStartsWith_NullString(string filter)
        {
            var model = new SieveModel {Filters = filter};

            var result = _processor.Apply(model, _comments);

            Assert.Equal(new[] {0, 2}, result.Select(p => p.Id));
        }
    }
}