using UnityEngine;
using UnityEngine.TestTools;
using NUnit.Framework;
using System.Collections;
using System.Collections.Generic;
using UnityEditor;

public class GuidReferenceTests
{
    // Tests - make a new GUID
    // duplicate it
    // make it a prefab
    // delete it
    // reference it
    // dereference it

    string prefabPath;
    GuidComponent guidBase;
    GameObject prefab;
    GuidComponent guidPrefab;

    [OneTimeSetUp]
    public void Setup()
    {
        prefabPath = "Assets/TemporaryTestGuid.prefab";

        guidBase = CreateNewGuid();
        prefab = PrefabUtility.CreatePrefab(prefabPath, guidBase.gameObject);

        guidPrefab = prefab.GetComponent<GuidComponent>();
    }

    public GuidComponent CreateNewGuid()
    {
        GameObject newGO = new GameObject("GuidTestGO");
        return newGO.AddComponent<GuidComponent>();
    }
    
    [UnityTest]
    public IEnumerator GuidCreation()
    {
        GuidComponent guid1 = guidBase;
        GuidComponent guid2 = CreateNewGuid();

        Assert.AreNotEqual(guid1.GetGuid(), guid2.GetGuid());

        yield return null;
    }

    [UnityTest]
    public IEnumerator GuidDuplication()
    {
        LogAssert.Expect(LogType.Warning, "Guid Collision Detected while creating GuidTestGO(Clone).\nAssigning new Guid.");
        
        GuidComponent clone = GameObject.Instantiate<GuidComponent>(guidBase);

        Assert.AreNotEqual(guidBase.GetGuid(), clone.GetGuid());

        yield return null;
    }

    [UnityTest]
    public IEnumerator GuidPrefab()
    {
        Assert.AreNotEqual(guidBase.GetGuid(), guidPrefab.GetGuid());
        Assert.AreEqual(guidPrefab.GetGuid(), System.Guid.Empty);

        yield return null;
    }

    [UnityTest]
    public IEnumerator GuidPrefabInstance()
    {
        GuidComponent instance = GameObject.Instantiate<GuidComponent>(guidPrefab);
        Assert.AreNotEqual(guidBase.GetGuid(), instance.GetGuid());
        Assert.AreNotEqual(instance.GetGuid(), guidPrefab.GetGuid());

        yield return null;
    }

    [UnityTest]
    public IEnumerator GuidValidReference()
    {
        GuidReference reference = new GuidReference(guidBase);
        Assert.AreEqual(reference.gameObject, guidBase.gameObject);

        yield return null;
    }

    [UnityTest]
    public IEnumerator GuidInvalidReference()
    {
        GuidComponent newGuid = CreateNewGuid();
        GuidReference reference = new GuidReference(newGuid);
        Object.DestroyImmediate(newGuid);

        Assert.IsNull(reference.gameObject);

        yield return null;
    }

    [OneTimeTearDown]
    public void TearDown()
    {
        AssetDatabase.DeleteAsset(prefabPath);
    }
}