using System;
using System.Linq;
using NUnit.Framework;
using NUnit.Framework.Interfaces;
using NUnit.Framework.Internal;

namespace UnityEditor.TestTools
{
    /// <summary>
    /// The `RequirePlatformSupportAttribute` attribute can be applied to test assemblies (will affect every test in the assembly), fixtures (will
    /// affect every test in the fixture), or to individual test methods.
    /// </summary>
    [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Class | AttributeTargets.Method)]
    public class RequirePlatformSupportAttribute : NUnitAttribute, IApplyToTest
    {
        /// <summary>
        /// Initializes and returns an instance of RequirePlatformSupportAttribute.
        /// </summary>
        /// <param name="platforms">The <see cref="BuildTarget"/> platform to run the test on.</param>
        public RequirePlatformSupportAttribute(params BuildTarget[] platforms)
        {
            this.platforms = platforms;
        }

        /// <summary>
        /// The build target platform, see [BuildTarget](https://docs.unity3d.com/ScriptReference/BuildTarget.html).
        /// </summary>
        /// <value>The <see cref="BuildTarget"/> platform to run the test on.</value>
        public BuildTarget[] platforms { get; private set; }

        /// <summary>
        /// Modifies a test as defined for the specific attribute.
        /// </summary>
        /// <param name="test">The test to modify</param>
        void IApplyToTest.ApplyToTest(Test test)
        {
            test.Properties.Add(PropertyNames.Category, string.Format("RequirePlatformSupport({0})", string.Join(", ", platforms.Select(p => p.ToString()).OrderBy(p => p).ToArray())));

            if (!platforms.All(p => BuildPipeline.IsBuildTargetSupported(BuildTargetGroup.Unknown, p)))
            {
                var missingPlatforms = platforms.Where(p => !BuildPipeline.IsBuildTargetSupported(BuildTargetGroup.Unknown, p)).Select(p => p.ToString()).ToArray();
                string skipReason = "Test cannot be run as it requires support for the following platforms to be installed: " + string.Join(", ", missingPlatforms);

                test.RunState = RunState.Skipped;
                test.Properties.Add(PropertyNames.SkipReason, skipReason);
            }
        }
    }
}
