using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityStandardAssets.CrossPlatformInput;

public class Player : MonoBehaviour {

    // Config 
    [SerializeField] float runSpeed = 5f;
    [SerializeField] float jumpSpeed = 5f;
    [SerializeField] float climbSpeed = 5f;
    [SerializeField] Vector2 deathKick = new Vector2(25f, 25f);

    // State
    bool isAlive = true;

    // Cached component references
    Rigidbody2D myRigidBody;
    Animator myAnimator;
    CapsuleCollider2D myBodyCollider;
    BoxCollider2D myFeet;
    float gravityScaleAtStart;

    // Message then methods
    void Start() {
        myRigidBody = GetComponent<Rigidbody2D>();
        myAnimator = GetComponent<Animator>();
        myBodyCollider = GetComponent<CapsuleCollider2D>();
        myFeet = GetComponent<BoxCollider2D>();
        gravityScaleAtStart = myRigidBody.gravityScale;
    }

    // Update is called once per frame
    void Update()
    {
        if (!isAlive) { return; }

        Run();
        ClimbLadder();
        Jump();
        FlipSprite();
        Die();
    }

    private void Run()
    {
        float controlThrow = CrossPlatformInputManager.GetAxis("Horizontal"); // value is betweeen -1 to +1
        Vector2 playerVelocity = new Vector2(controlThrow * runSpeed, myRigidBody.velocity.y);
        myRigidBody.velocity = playerVelocity;

        bool playerHasHorizontalSpeed = Mathf.Abs(myRigidBody.velocity.x) > Mathf.Epsilon;
        myAnimator.SetBool("Running", playerHasHorizontalSpeed);
    }

    private void ClimbLadder()
    {
        if (!myFeet.IsTouchingLayers(LayerMask.GetMask("Climbing")))
        {
            myAnimator.SetBool("Climbing", false);
            myRigidBody.gravityScale = gravityScaleAtStart;
            return;
        }

        float controlThrow = CrossPlatformInputManager.GetAxis("Vertical");
        Vector2 climbVelocity = new Vector2(myRigidBody.velocity.x, controlThrow * climbSpeed);
        myRigidBody.velocity = climbVelocity;
        myRigidBody.gravityScale = 0f;

        bool playerHasVerticalSpeed = Mathf.Abs(myRigidBody.velocity.y) > Mathf.Epsilon;
        myAnimator.SetBool("Climbing", playerHasVerticalSpeed);

    }

    private void Jump()
    {
        if (!myFeet.IsTouchingLayers(LayerMask.GetMask("Ground"))) { return; }

        if (CrossPlatformInputManager.GetButtonDown("Jump"))
        {
            Vector2 jumpVelocityToAdd = new Vector2(0f, jumpSpeed);
            myRigidBody.velocity += jumpVelocityToAdd;
        }
    }

    private void Die()
    {
        if (myBodyCollider.IsTouchingLayers(LayerMask.GetMask("Enemy", "Hazards")))
        {
            isAlive = false;
            myAnimator.SetTrigger("Dying");
            GetComponent<Rigidbody2D>().velocity = deathKick;
            FindObjectOfType<GameSession>().ProcessPlayerDeath();
        }
    }

    private void FlipSprite()
    {
        bool playerHasHorizontalSpeed = Mathf.Abs(myRigidBody.velocity.x) > Mathf.Epsilon;
        if (playerHasHorizontalSpeed)
        {
            transform.localScale = new Vector2(Mathf.Sign(myRigidBody.velocity.x), 1f);
        }
    }

}
