using System.Collections;
using UnityEngine;
using static UnityEngine.GraphicsBuffer;

public class PlayerController : MonoBehaviour
{
    public GameObject DougBody;
    public Shovel Shovel;
    public float walkSpeed;
    public float gravity = 10;

    float digTime = 0.9f;
    float digTimestamp = 0;
    bool isDigging = false;

    Interactable nearestInteractable;
    private CharacterController characterController;
    private CameraController cameraController;
    private Vector3 moveDir;
    private bool hasControl = true; // set this to false if we want to stop reading player inputs
    
    // Start is called once before the first execution of Update after the MonoBehaviour is created
    void Start()
    {
        characterController = GetComponent<CharacterController>();
        cameraController = GetComponent<CameraController>();
    }

    // Update is called once per frame
    void Update()
    {
        moveDir = Vector3.zero;

        if (hasControl)
        {
            if (!isDigging)
            {
                RotatePlayerTowardMouse();
                TryInteract();
            }

            DigDetector();
            ApplyWalk();

            // TODO: This is just for testing, remove or clean up if used
            if (Input.GetKeyDown(KeyCode.LeftShift))
            {
                cameraController.RotateCam();
            }

            // TODO: Add actual save feature later, this is just for test
            if (Input.GetKeyDown(KeyCode.I))
            {
                SaveSystem.Save();
            }
        }

        ApplyGravity();
        DoMovement();
    }

    /// <summary>
    /// Apply walking inputs to moveDir
    /// </summary>
    void ApplyWalk()
    {
        float verticalMovement = 0;
        float horizontalMovement = 0;

        if (!isDigging)
        {
            verticalMovement = Input.GetAxisRaw("Vertical");
            horizontalMovement = Input.GetAxisRaw("Horizontal");
        }

        moveDir = new Vector3(horizontalMovement, 0, verticalMovement).normalized;

        if (cameraController != null)
        {
            // re-matrix the rotation direction so movement is consistent no matter what
            // the camera rotation is

            Matrix4x4 matrix = Matrix4x4.Rotate(Quaternion.Euler(0, cameraController.playerCamHome.rotation.eulerAngles.y, 0));
            moveDir = matrix.MultiplyPoint3x4(moveDir);
        }
    }

    /// <summary>
    /// Apply gravity to moveDir
    /// </summary>
    void ApplyGravity()
    {
        moveDir *= walkSpeed;

        if (!characterController.isGrounded)
        {
            moveDir.y = -gravity;
        }
    }

    /// <summary>
    /// Move character with moveDir 
    /// </summary>
    void DoMovement()
    {
        characterController.Move(moveDir * Time.deltaTime);
    }

    /// <summary>
    /// Pass movement into character controller, lets us expose function without exposing
    /// whole char controller
    /// </summary>
    public void CharacterControllerMove(Vector3 movement)
    {
        characterController.Move(movement);
    }

    /// <summary>
    /// Auto-walk the character in the specified direction. Uses character's walk
    /// speed and camera rotation (per-frame)
    /// </summary>
    public void WalkInDirection(Vector3 direction)
    {
        Vector3 forwardDir = direction;
        forwardDir.y = 0; // don't move on the y axis
        forwardDir *= walkSpeed;

        characterController.Move(forwardDir * Time.deltaTime);
    }

    /// <summary>
    /// Detect input for digging (will eventually be tool agnostic)
    /// </summary>
    void DigDetector()
    {
        if (!isDigging)
        {
            if (Input.GetMouseButtonDown(0))
            {
                Shovel.Dig();
                isDigging = true;
                digTimestamp = Time.time + digTime; // fuck coroutines fr fr
            }
        }
        else
        {
            if (Time.time > digTimestamp)
            {
                isDigging = false;
            }
        }
    }

    /// <summary>
    /// Face character graphic toward mouse
    /// </summary>
    void RotatePlayerTowardMouse()
    {
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        RaycastHit hit;

        if (Physics.Raycast(ray, out hit, Mathf.Infinity))
        {
            Vector3 targetPosition = hit.point;
            targetPosition.y = transform.position.y; 

            Vector3 direction = targetPosition - transform.position;
            Quaternion targetRotation = Quaternion.LookRotation(direction, Vector3.up);

            DougBody.transform.rotation = targetRotation;
        }
    }

    /// <summary>
    /// Try to interact by detecting nearest interactable
    /// </summary>
    void TryInteract()
    {
        if (Input.GetKeyDown(KeyCode.E) && nearestInteractable != null)
        {
            nearestInteractable.Interact();
        }
    }

    private void OnTriggerEnter(Collider other)
    {
        Interactable interactable = other.GetComponent<Interactable>();

        // store nearest interactable if it exists
        if (interactable != null)
        {
            nearestInteractable = interactable;
            interactable.MoveInsideRange();
        }
    }

    private void OnTriggerExit(Collider other)
    {
        // just null out interactables when we leave an interactable trigger (we cant and shouldn't overlap interactables)
        Interactable interactable = other.GetComponent<Interactable>();

        // store nearest interactable if it exists
        if (interactable != null && nearestInteractable != null)
        {
            nearestInteractable.MoveOutsideRange();
            nearestInteractable = null;
        }
    }

    /// <summary>
    /// Sets the character's "hasControl" bool. All input is ignored when false
    /// </summary>
    public void SetCharacterControl(bool hasControl)
    {
        this.hasControl = hasControl;
    }

    /// <summary>
    /// Gets the character's "hasControl" bool. All input is ignored when false
    /// </summary>
    public bool GetCharacterHasControl()
    {
        return hasControl;
    }
}