using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Player : MonoBehaviour
{
    [SerializeField]
    private float powerLevel;
    public float PowerLevel
    {
        get
        {
            return powerLevel;
        }
        set
        {
            powerLevel = value;

            if (powerLevel > powerLevelMax)
            {
                powerLevel = powerLevelMax;
            }
        }
    }

    public float startSpeed = 5f;
    public float lookSmoothingSeconds = 0.05f;
    public float cameraSmoothingSeconds = 1;
    public float bulletUpBias = 0.1f;
    public float bulletForce = 10f;
    public float powerLevelMax = 8.0f;
    public Transform gunTransform;
    public Rigidbody bulletPrefab;
    public Light muzzleLight;

    private Vector3 inputDirection;
    private float speed;
    private Vector3 lookDirection;
    private float deadZone = 0.1f;
    private Vector3 lookVelocity;
    private Vector3 cameraOffset;
    private Vector3 cameraVelocity;
    private bool shooting = false;
    private float lightIntensity;

    // Use this for initialization
	void Start ()
	{
	    speed = startSpeed;
	    cameraOffset = Camera.main.transform.position - transform.position;
	    lightIntensity = muzzleLight.intensity;
	}
	
	// Update is called once per frame
	void Update ()
	{
        // TODO lerp movement direction
        GetInput();

        if (lookDirection.magnitude > deadZone)
            transform.forward = Vector3.SmoothDamp(transform.forward, lookDirection, ref lookVelocity, lookSmoothingSeconds);
	    transform.position += inputDirection * speed * Time.deltaTime;

	    Camera.main.transform.position = Vector3.SmoothDamp(Camera.main.transform.localPosition, TargetCameraPosition(), ref cameraVelocity, cameraSmoothingSeconds);

	    if (shooting)
        {
            if (Time.frameCount % 2 == 0)
            {
                muzzleLight.intensity = 0;
            }
            else
            {
                muzzleLight.intensity = Random.Range(.5f,2f) * lightIntensity;
            }
            Shoot();
	    }
	    else
	    {
	        muzzleLight.intensity = 0;
	    }
	}

    private void Shoot()
    {
        var rb = Instantiate<Rigidbody>(bulletPrefab);
        rb.transform.position = gunTransform.position;
        rb.transform.forward = gunTransform.forward;
        rb.AddForce(bulletForce * (transform.forward + Vector3.up * bulletUpBias), ForceMode.VelocityChange);
        Destroy(rb.gameObject, 2f);
    }

    private Vector3 TargetCameraPosition()
    {
        return transform.position + cameraOffset;
    }

    void GetInput()
    {
        shooting = Input.GetButton("Fire1");
        lookDirection = new Vector3(
            Input.GetAxis("LookX"),
            0,
            -Input.GetAxis("LookY")
        ).normalized;
        inputDirection = new Vector3(
            Input.GetAxis("Horizontal"),
            0,
            Input.GetAxis("Vertical")
        ).normalized;
    }
}