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

public class FirstPersonController : MonoBehaviour
{
    // Start is called before the first frame update
    public bool CanMove { get; private set; } = true;
    private bool IsSprinting => canSprint && Input.GetKey(sprintKey);
    private bool ShouldJump => Input.GetKeyDown(jumpKey) && characterController.isGrounded;
    private bool ShouldCrouch => Input.GetKeyDown(crouchKey) && !duringCrouchAnimation && characterController.isGrounded;

    [Header("Functional Options")]
    [SerializeField] private bool canSprint = true;
    [SerializeField] private bool canJump = true;
    [SerializeField] private bool canCrouch = true;
    [SerializeField] private bool  canUseHeadbob = true;

    [Header("Controls")]
    [SerializeField] private KeyCode sprintKey = KeyCode.LeftShift;
    [SerializeField] private KeyCode jumpKey = KeyCode.Space;
    [SerializeField] private KeyCode crouchKey = KeyCode.C;

    [Header("Movement Parameters")]
    [SerializeField] private float walkSpeed = 3.0f;
    [SerializeField] private float sprintSpeed = 6.0f;
    [SerializeField] private float crouchSpeed = 1.5f;


    [Header("Look Parameters")]
    [SerializeField, Range(1, 10)] private float lookSpeedX = 2.0f;
    [SerializeField, Range(1, 10)] private float lookSpeedY = 2.0f;
    [SerializeField, Range(1, 180)] private float upperLookLimit = 80.0f;
    [SerializeField, Range(1, 180)] private float lowerLookLimit = 80.0f;

    [Header("Jumping Parameters")]
    [SerializeField] private float jumpForce = 8.0f;
    [SerializeField] private float gravity = 30.0f;

    [Header("Crouch Parameters")]
    [SerializeField] private float crouchHeight = 0.5f;
    [SerializeField] private float standingHeight = 2.0f;
    [SerializeField] private float timeToCrouch = 0.25f;
    [SerializeField] private Vector3 crouchingCenter = new Vector3(0,0.5f,0);
    [SerializeField] private Vector3 standingCenter = new Vector3(0,0,0);
    private bool isCrouching;
    private bool duringCrouchAnimation;

    [Header("Headbob Parameters")]
    [SerializeField] private float walkBobSpeed = 14f;
    [SerializeField] private float walkBobAmount = 0.05f;
    [SerializeField] private float sprintBobSpeed = 18f;
    [SerializeField] private float sprintBobAmount = 0.1f;    
    [SerializeField] private float crouchBobSpeed = 8f;
    [SerializeField] private float crouchBobAmount = 0.025f;
    private float defaultYPos = 0;
    private float timer ;

    private Camera playerCamera;
    private CharacterController characterController;

    private Vector3 moveDirection;
    private Vector2 currentInput;

    private float rotationX = 0;
    
    void Awake()
    {
        playerCamera = GetComponentInChildren<Camera>();
        characterController = GetComponent<CharacterController>();
        defaultYPos = playerCamera.transform.localPosition.y;
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;

    }

    // Update is called once per frame
    void Update()
    {
        if (CanMove)
        {
            HandleMovementInput();
            HandleMouseLook();

            if (canJump)
                HandleJump();

            if (canCrouch)
                HandleCrouch();

            if (canUseHeadbob)
                HandleHeadbob();

            ApplyFinalMovements();
        }
    }

    private void HandleMovementInput()
    {
        currentInput = new Vector2((isCrouching ? crouchSpeed : IsSprinting ? sprintSpeed : walkSpeed)* Input.GetAxis("Vertical"), (isCrouching ? crouchSpeed : IsSprinting ? sprintSpeed : walkSpeed) * Input.GetAxis("Horizontal"));

        float moveDirectionY = moveDirection.y;
        moveDirection = (transform.TransformDirection(Vector3.forward) * currentInput.x) + (transform.TransformDirection(Vector3.right) * currentInput.y);
        moveDirection.y = moveDirectionY;
    }

    private void HandleJump()
    {
        if (ShouldJump)
            moveDirection.y = jumpForce;
    }

    private void HandleCrouch()
    {
        if (ShouldCrouch)
            StartCoroutine(CrouchStand());
    }

    private void HandleHeadbob()
    {
        if (!characterController.isGrounded) return;

        if(Mathf.Abs(moveDirection.x) >0.1f || Mathf.Abs(moveDirection.z) > 0.1f)
        {
                timer += Time.deltaTime * (isCrouching ? crouchBobSpeed : IsSprinting ? sprintBobSpeed : walkBobSpeed);
                playerCamera.transform.localPosition = new Vector3(
                    playerCamera.transform.localPosition.x,
                    defaultYPos + Mathf.Sin(timer) * (isCrouching ? crouchBobAmount : IsSprinting ? sprintBobAmount : walkBobAmount),
                    playerCamera.transform.localPosition.z);
        }

    }

    private void HandleMouseLook()
    {
        rotationX -= Input.GetAxis("Mouse Y") * lookSpeedY;
        rotationX = Mathf.Clamp(rotationX, -upperLookLimit, lowerLookLimit);
        playerCamera.transform.localRotation = Quaternion.Euler(rotationX, 0, 0);
        transform.rotation *= Quaternion.Euler(0, Input.GetAxis("Mouse X") * lookSpeedX, 0);
    }

    private void ApplyFinalMovements()
    {
        if (!characterController.isGrounded)
            moveDirection.y -= gravity * Time.deltaTime;

        characterController.Move(moveDirection * Time.deltaTime);
    }   
    
    private IEnumerator CrouchStand()
    {
        if (isCrouching && Physics.Raycast(playerCamera.transform.position, Vector3.up, 1f))
                    yield break;
        duringCrouchAnimation = true;

        float timeElapsed = 0;
        float targetHeight = isCrouching ? standingHeight : crouchHeight;
        float currentHeight = characterController.height;
        Vector3 targetCenter = isCrouching ? standingCenter : crouchingCenter;
        Vector3 currentCenter = characterController.center;

        while (timeElapsed < timeToCrouch)
        {
            characterController.height = Mathf.Lerp(currentHeight, targetHeight, timeElapsed / timeToCrouch);
            characterController.center = Vector3.Lerp(currentCenter, targetCenter, timeElapsed);
            timeElapsed += Time.deltaTime;
            yield return null;
        }

        characterController.height = targetHeight;
        characterController.center = targetCenter;

        isCrouching = !isCrouching;

        duringCrouchAnimation = false;
    }

}