using System;

using NUnit.Framework;
using FluentAssertions;
using Encompass;
using System.Collections.Generic;

namespace Tests
{
    public class OrderedRendererTest
    {
        struct AComponent : IComponent { }
        struct BComponent : IComponent { }
        struct CComponent : IComponent { }

        struct TestDrawComponent : IComponent { }

        class TestRenderer : OrderedRenderer<TestDrawComponent>
        {
            public override void Render(Guid drawComponentID, TestDrawComponent testDrawComponent) { }
        }

        static bool called = false;
        class DeactivatedRenderer : TestRenderer
        {
            public override void Render(Guid drawComponentID, TestDrawComponent testDrawComponent)
            {
                called = true;
            }
        }

        static bool calledOnDraw = false;
        static ValueTuple<Guid, TestDrawComponent> resultComponent;

        class CalledRenderer : OrderedRenderer<TestDrawComponent>
        {
            public override void Render(Guid drawComponentID, TestDrawComponent testDrawComponent)
            {
                resultComponent = (drawComponentID, testDrawComponent);
                calledOnDraw = true;
            }
        }

        [Test]
        public void RenderMethodCalledOnWorldDraw()
        {
            var worldBuilder = new WorldBuilder();
            var renderer = worldBuilder.AddOrderedRenderer(new CalledRenderer());

            AComponent aComponent;
            CComponent cComponent;
            TestDrawComponent testDrawComponent;

            var entity = worldBuilder.CreateEntity();
            worldBuilder.AddComponent(entity, aComponent);
            worldBuilder.AddComponent(entity, cComponent);
            var testDrawComponentID = worldBuilder.AddDrawComponent(entity, testDrawComponent, 2);

            var world = worldBuilder.Build();

            world.Update(0.01f);
            world.Draw();

            Assert.IsTrue(calledOnDraw);
            resultComponent.Should().BeEquivalentTo((testDrawComponentID, testDrawComponent));
        }

        [Reads(typeof(TestDrawComponent))]
        class DestroyerEngine : Engine
        {
            public override void Update(double dt)
            {
                foreach (var (componentID, component) in ReadComponents<TestDrawComponent>())
                {
                    Destroy(GetEntityIDByComponentID(componentID));
                }
            }
        }
        [Test]
        public void RenderMethodNotCalledAfterDestroy()
        {
            calledOnDraw = false;

            var worldBuilder = new WorldBuilder();
            worldBuilder.AddEngine(new DestroyerEngine());
            var renderer = worldBuilder.AddOrderedRenderer(new CalledRenderer());

            TestDrawComponent testDrawComponent;

            var entity = worldBuilder.CreateEntity();
            var testDrawComponentID = worldBuilder.AddDrawComponent(entity, testDrawComponent, 1);

            var world = worldBuilder.Build();

            world.Update(0.01);
            world.Draw();

            Assert.IsFalse(calledOnDraw);
        }
    }
}