using System;
using System.Collections;
using System.Collections.Generic;
using Unity.VisualScripting;
using UnityEngine;
using UnityEngine.Animations;
using UnityEngine.UIElements;

public class PickUpObject : MonoBehaviour
{
    public GameObject carryPosition; // blank object, position declares where the object will be teleported to/carried
    public bool insideTrigger = false; // checks if player is inside the trigger of a pickup object 
    public bool carrying = false; // checks if player is carrying an object
    public GameObject carriableObject; // object newest object that player can carry
    public GameObject previousObject; // previous object that player was carrying
    public GameObject heldObject; // object that player is currently holding
    public float throwForce; // force that player throws object with
    public float cooldown; // time between picking up objects
    public bool cooldownActive; // checks if cooldown is active
    
    // Start is called before the first frame update
    void Start()
    {
        cooldown = 1;
        cooldownActive = true;
    }

    // Update is called once per frame
    void Update()
    {
        // Checks if timer is below 0, if so, turns cooldownActive off, if not, activates cooldown
        cooldown -= Time.deltaTime; 
        if(cooldown <= 0)
        {
            cooldownActive = false;
        }
        else
        {
            cooldownActive = true;
        }

        // If previous object is not held object or null, applies gravity to it
        if(previousObject != null)
        {
            if(previousObject.GetComponent<Rigidbody>().useGravity == false)
            {
                previousObject.GetComponent<Rigidbody>().useGravity = true;
            }
        }

        // If player is inside trigger and presses F, pick up object
        if(insideTrigger && Input.GetKeyDown(KeyCode.F) && !cooldownActive)
        {
            // Disables gravity on object and sets carrying to true
            carriableObject.GetComponent<Rigidbody>().useGravity = false;
            carrying = true;
            // Sets held object to carriable object and sets cooldown to 1
            heldObject = carriableObject;
            cooldown = 1;
        }
        // If player is carrying object and presses F, drop object
        else if(carrying && Input.GetKeyDown(KeyCode.F))
        {
            // Re-enables gravity on object and sets carrying to false and assigns held object to previous object
            heldObject.GetComponent<Rigidbody>().useGravity = true;
            previousObject = heldObject;
            carrying = false;
            // Drop the object in the direction the player is moving and add a force to it depending on speed
            previousObject.GetComponent<Rigidbody>().AddForce(transform.forward * throwForce, ForceMode.Impulse);
        }

        // If player is carrying object, teleport object to carry position
        if(carrying)
        {
            carriableObject.transform.position = carryPosition.transform.position;
            carriableObject.transform.rotation = carryPosition.transform.rotation;
        }
    }

    // If player is inside trigger tagged as PickupObject, set carriable object to object inside trigger
    void OnTriggerStay(Collider other)
    {
        if(other.gameObject.tag == "PickupObject" && !cooldownActive)
        {
            carriableObject = other.gameObject;
            // If player is inside trigger, set inside trigger to true
            insideTrigger = true;
            // If player is holding an object and it is not the carriable object, set previous object to held object and set cooldown to 1
            if(heldObject != carriableObject && heldObject != null && carrying)
            {
                previousObject = heldObject;
                cooldown = 1;
            }
        }
    }

    // If player is not inside trigger, set inside trigger to false
    void OnTriggerExit(Collider other)
    {
        if(other.gameObject.tag == "PickupObject")
        {
            insideTrigger = false;
        }
    }
}


//! To make player launch self:
//! add public GameObject player; and place player in it fron inspector
//! in if(insiderTrigger && Input.GetKeyDown(KeyCode.F))
//! Place the code below:
//! player.GetComponent<Rigidbody>().AddForce(transform.forward * throwForce, ForceMode.Impulse);
//! Run the game and press F to launch the player