using System;
using NUnit.Framework;

namespace Chernobyl
{
    [TestFixture, Description("Tests for the Validation type.")]
    public class ValidationTests
    {
        #region IfNull Tests

        [Test, Description("Ensures IfNull throws if value is null.")]
        public void IfNullThrowsWhenValueIsNull() => Assert.Throws<ArgumentNullException>(() => ((object)null).Throw("value").IfNull());

        [Test, Description("Ensures IfNull does not throw if value is not null.")]
        public void IfNullDoesNotThrowWhenValueIsNotNull() => Assert.DoesNotThrow(() => "not null".Throw("value").IfNull());

        #endregion

        #region IfLessThan Tests

        [Test, Description("Ensures IfLessThan throws if value is less than provided value.")]
        public void ThrowIfLessThanThrowsWhenValueIsLess()
        {
            Assert.Throws<ArgumentOutOfRangeException>(() => 3.Throw("value").IfLessThan(4));
        }

        [Test, Description("Ensures IfLessThan does not throw if value is equal to provided value.")]
        public void ThrowIfLessThanDoesNotThrowWhenValuesAreEqual()
        {
            Assert.DoesNotThrow(() => 3.Throw("value").IfLessThan(3));
        }

        [Test, Description("Ensures IfLessThan does not throw if value is greater than to provided value.")]
        public void ThrowIfLessThanDoesNotThrowWhenValueIsGreaterThan()
        {
            Assert.DoesNotThrow(() => 3.Throw("value").IfLessThan(2));
        }

        #endregion

        #region IfLessThanOrEqualTo Tests

        [Test, Description("Ensures IfLessThanOrEqualTo throws if value is less than provided value.")]
        public void ThrowIfLessThanOrEqualToThrowsWhenValueIsLess()
        {
            Assert.Throws<ArgumentOutOfRangeException>(() => 3.Throw("value").IfLessThanOrEqualTo(4));
        }

        [Test, Description("Ensures IfLessThanOrEqualTo does not throw if value is equal to provided value.")]
        public void ThrowIfLessThanOrEqualToDoesNotThrowWhenValuesAreEqual()
        {
            Assert.Throws<ArgumentOutOfRangeException>(() => 3.Throw("value").IfLessThanOrEqualTo(3));
        }

        [Test, Description("Ensures IfLessThanOrEqualTo does not throw if value is greater than to provided value.")]
        public void ThrowIfLessThanOrEqualToDoesNotThrowWhenValueIsGreaterThan()
        {
            Assert.DoesNotThrow(() => 3.Throw("value").IfLessThanOrEqualTo(2));
        }

        #endregion

        #region IfGreaterThan Tests

        [Test, Description("Ensures IfGreaterThan throws if value is greater than provided value.")]
        public void ThrowIfGreaterThanThrowsWhenValueIsGreater()
        {
            Assert.Throws<ArgumentOutOfRangeException>(() => 3.Throw("value").IfGreaterThan(2));
        }

        [Test, Description("Ensures IfGreaterThan does not throw if value is equal to provided value.")]
        public void ThrowIfGreaterThanDoesNotThrowWhenValuesAreEqual()
        {
            Assert.DoesNotThrow(() => 3.Throw("value").IfGreaterThan(3));
        }

        [Test, Description("Ensures IfGreaterThan does not throw if value is less than provided value.")]
        public void ThrowIfGreaterThanDoesNotThrowWhenValueIsLessThan()
        {
            Assert.DoesNotThrow(() => 3.Throw("value").IfGreaterThan(4));
        }

        #endregion

        #region IfGreaterThanOrEqualTo Tests

        [Test, Description("Ensures ThrowIfGreaterThanEqualTo throws if value is greater than provided value.")]
        public void ThrowIfGreaterThanOrEqualToWhenValueIsGreater()
        {
            Assert.Throws<ArgumentOutOfRangeException>(() => 3.Throw("value").IfGreaterThanOrEqualTo(2));
        }

        [Test, Description("Ensures IfGreaterThanOrEqualTo throws if value is equal to provided value.")]
        public void ThrowIfGreaterThanOrEqualToThrowsWhenValuesAreEqual()
        {
            Assert.Throws<ArgumentOutOfRangeException>(() => 3.Throw("value").IfGreaterThanOrEqualTo(3));
        }

        [Test, Description("Ensures IfGreaterThanOrEqualTo does not throw if value is less than provided value.")]
        public void ThrowIfGreaterThanOrEqualToDoesNotThrowWhenValueIsLessThan()
        {
            Assert.DoesNotThrow(() => 3.Throw("value").IfGreaterThanOrEqualTo(4));
        }

        #endregion

        #region IfEmpty Tests

        [Test, Description("Ensures IfEmpty throws when collection is empty.")]
        public void ThrowIfEmptyThrowsWhenCollectionIsEmpty()
        {
            Assert.Throws<ArgumentException>(() => "".Throw("value").IfEmpty());
        }

        [Test, Description("Ensures IfEmpty throws when collection is empty.")]
        public void ThrowIfEmptyDoesNotThrowIfCollectionNotEmpty()
        {
            Assert.DoesNotThrow(() => "hello".Throw("value").IfEmpty());
        }

        #endregion

    }
}