using UnityEngine;
using UnityEngine.SceneManagement;

public class Rocket : MonoBehaviour
{
    [SerializeField] float rcsThrust = 100f;
    [SerializeField] float mainThrust = 100f;
    [SerializeField] float levelLoadDelay = 2f;
    [SerializeField] float loadCurrentLevel = 1f;

    [SerializeField] AudioClip mainEngine;
    [SerializeField] AudioClip success;
    [SerializeField] AudioClip death;

    [SerializeField] ParticleSystem mainEngineParticles;
    [SerializeField] ParticleSystem successParticles;
    [SerializeField] ParticleSystem deathParticles;

    Rigidbody rigidBody;
    AudioSource audioSource;

    bool isTransitioning = false;
    bool collisionsDisabled = false;

    // Use this for initialization
    void Start()
    {
        rigidBody = GetComponent<Rigidbody>();
        audioSource = GetComponent<AudioSource>();
    }

    // Update is called once per frame
    void Update()
    {
        if (!isTransitioning)
        {
            RespondToThrustInput();
            RespondToRotateInput();
        }
        if (Debug.isDebugBuild)
        {
            // todo only if debug on
            RespondToDebugKeys();
        }
    }
    private void RespondToDebugKeys()
    {
        if (Input.GetKeyDown(KeyCode.L))
        {
            LoadNextLevel();
        }
        else if (Input.GetKeyDown(KeyCode.C))
        {
            collisionsDisabled = !collisionsDisabled; // toggle
        }
    }


    void OnCollisionEnter(Collision collision)
    {
            if (isTransitioning || collisionsDisabled) { return; }

        switch (collision.gameObject.tag)
        {
            case "Friendly":
                // do nothing
                break;
            case "Finish":
                StartSuccessSequence();
                break;
            default:
                StartDeathSequence();
                break;
        }
    }

    private void StartSuccessSequence()
    {
        isTransitioning = true;
        audioSource.Stop();
        audioSource.PlayOneShot(success);
        successParticles.Play();
        Invoke("LoadCurrentLevel", levelLoadDelay);

    }

    private void StartDeathSequence()
    {
        isTransitioning = true;
        audioSource.Stop();
        audioSource.PlayOneShot(death);
        deathParticles.Play();
        Invoke("LoadCurrentLevel", levelLoadDelay);
    }
    private void LoadCurrentLevel()
    {
        int currentScene = SceneManager.GetActiveScene().buildIndex;
        SceneManager.LoadScene(currentScene);
    }
    private void LoadNextLevel()
    {
        int currentSceneIndex = SceneManager.GetActiveScene().buildIndex;
        int LoadCurrentLevel = currentSceneIndex + 1;
        if (LoadCurrentLevel == SceneManager.sceneCountInBuildSettings)
        {
            LoadCurrentLevel // loop back to level died in
        }
        SceneManager.LoadScene(nextSceneIndex);
    }

    private void LoadFirstLevel()
    {
        SceneManager.LoadScene(LoadCurrentLevel);
    }

    private void RespondToThrustInput()
    {
        if (Input.GetKey(KeyCode.Space)) // can thrust while rotating
        {
            ApplyThrust();
        }
        else
        {
            StopApplyingThrust();
        }
    }

    private void StopApplyingThrust()
    {
        audioSource.Stop();
        mainEngineParticles.Stop();
    }

    private void ApplyThrust()
    {
        rigidBody.AddRelativeForce(Vector3.up * mainThrust);
        if (!audioSource.isPlaying) // so it doesn't layer
        {
            audioSource.PlayOneShot(mainEngine);
        }
        mainEngineParticles.Play();
    }

    private void RespondToRotateInput()
    {
        rigidBody.angularVelocity = Vector3.zero; // remove rotation due to pyhsics

        float rotationThisFrame = rcsThrust * Time.deltaTime;
        if (Input.GetKey(KeyCode.A))
        {
            transform.Rotate(Vector3.forward * rotationThisFrame);
        }
        else if (Input.GetKey(KeyCode.D))
        {
            transform.Rotate(-Vector3.forward * rotationThisFrame);
        }

    }
}