// ==========================================================================
//  Squidex Headless CMS
// ==========================================================================
//  Copyright (c) Squidex UG (haftungsbeschränkt)
//  All rights reserved. Licensed under the MIT license.
// ==========================================================================

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using FluentAssertions;
using Squidex.Domain.Apps.Core.Contents;
using Squidex.Domain.Apps.Core.Schemas;
using Squidex.Domain.Apps.Core.TestHelpers;
using Squidex.Domain.Apps.Core.ValidateContent;
using Squidex.Domain.Apps.Core.ValidateContent.Validators;
using Squidex.Infrastructure;
using Squidex.Infrastructure.Json.Objects;
using Xunit;

namespace Squidex.Domain.Apps.Core.Operations.ValidateContent
{
    public class ReferencesFieldTests : IClassFixture<TranslationsFixture>
    {
        private readonly List<string> errors = new List<string>();
        private readonly DomainId schemaId = DomainId.NewGuid();
        private readonly DomainId ref1 = DomainId.NewGuid();
        private readonly DomainId ref2 = DomainId.NewGuid();
        private readonly IValidatorsFactory factory;

        private class CustomFactory : IValidatorsFactory
        {
            private readonly DomainId schemaId;

            public CustomFactory(DomainId schemaId)
            {
                this.schemaId = schemaId;
            }

            public IEnumerable<IValidator> CreateValueValidators(ValidatorContext context, IField field, ValidatorFactory createFieldValidator)
            {
                if (field is IField<ReferencesFieldProperties> references)
                {
                    yield return new ReferencesValidator(references.Properties.IsRequired, references.Properties, ids =>
                    {
                        var result = ids.Select(x => (schemaId, x, Status.Published)).ToList();

                        return Task.FromResult<IReadOnlyList<(DomainId SchemaId, DomainId Id, Status Status)>>(result);
                    });
                }
            }
        }

        public ReferencesFieldTests()
        {
            factory = new CustomFactory(schemaId);
        }

        [Fact]
        public void Should_instantiate_field()
        {
            var sut = Field(new ReferencesFieldProperties());

            Assert.Equal("my-refs", sut.Name);
        }

        [Fact]
        public async Task Should_not_add_error_if_references_are_valid()
        {
            var sut = Field(new ReferencesFieldProperties
            {
                IsRequired = true,
                MinItems = 1,
                MaxItems = 3
            });

            await sut.ValidateAsync(CreateValue(ref1), errors, factory: factory);

            Assert.Empty(errors);
        }

        [Fact]
        public async Task Should_not_add_error_if_references_are_null_and_valid()
        {
            var sut = Field(new ReferencesFieldProperties());

            await sut.ValidateAsync(CreateValue(null), errors, factory: factory);

            Assert.Empty(errors);
        }

        [Fact]
        public async Task Should_not_add_error_if_number_of_references_is_equal_to_min_and_max_items()
        {
            var sut = Field(new ReferencesFieldProperties { MinItems = 2, MaxItems = 2 });

            await sut.ValidateAsync(CreateValue(ref1, ref2), errors, factory: factory);

            Assert.Empty(errors);
        }

        [Fact]
        public async Task Should_not_add_error_if_duplicate_values_are_allowed()
        {
            var sut = Field(new ReferencesFieldProperties { AllowDuplicates = true });

            await sut.ValidateAsync(CreateValue(ref1, ref1), errors, factory: factory);

            Assert.Empty(errors);
        }

        [Fact]
        public async Task Should_add_error_if_references_are_required_and_null()
        {
            var sut = Field(new ReferencesFieldProperties { SchemaId = schemaId, IsRequired = true });

            await sut.ValidateAsync(CreateValue(null), errors, factory: factory);

            errors.Should().BeEquivalentTo(
                new[] { "Field is required." });
        }

        [Fact]
        public async Task Should_add_error_if_references_are_required_and_empty()
        {
            var sut = Field(new ReferencesFieldProperties { SchemaId = schemaId, IsRequired = true });

            await sut.ValidateAsync(CreateValue(), errors, factory: factory);

            errors.Should().BeEquivalentTo(
                new[] { "Field is required." });
        }

        [Fact]
        public async Task Should_add_error_if_value_has_not_enough_items()
        {
            var sut = Field(new ReferencesFieldProperties { SchemaId = schemaId, MinItems = 3 });

            await sut.ValidateAsync(CreateValue(ref1, ref2), errors, factory: factory);

            errors.Should().BeEquivalentTo(
                new[] { "Must have at least 3 item(s)." });
        }

        [Fact]
        public async Task Should_add_error_if_value_has_too_much_items()
        {
            var sut = Field(new ReferencesFieldProperties { SchemaId = schemaId, MaxItems = 1 });

            await sut.ValidateAsync(CreateValue(ref1, ref2), errors, factory: factory);

            errors.Should().BeEquivalentTo(
                new[] { "Must not have more than 1 item(s)." });
        }

        [Fact]
        public async Task Should_add_error_if_reference_contains_duplicate_values()
        {
            var sut = Field(new ReferencesFieldProperties { SchemaId = schemaId });

            await sut.ValidateAsync(CreateValue(ref1, ref1), errors, factory: factory);

            errors.Should().BeEquivalentTo(
                new[] { "Must not contain duplicate values." });
        }

        private static IJsonValue CreateValue(params DomainId[]? ids)
        {
            return ids == null ?
                JsonValue.Null :
                JsonValue.Array(ids.Select(x => (object)x.ToString()).ToArray());
        }

        private static RootField<ReferencesFieldProperties> Field(ReferencesFieldProperties properties)
        {
            return Fields.References(1, "my-refs", Partitioning.Invariant, properties);
        }
    }
}