// This is a basic implementation of a touch-based player controller in Unity // The player can be moved by touching the screen and dragging to a new location

using UnityEngine; using System.Collections;

public class PlayerController1 : MonoBehaviour {

public GameObject circlePrefab; // Prefab for the circle that appears under the player when touched
private GameObject currentCircle; // The currently spawned circle (if any)
private Vector3 targetPosition; // The position the player is moving towards
private bool facingRight = true; // Whether or not the player is facing right

Coroutine currentCoroutine;

void Update()
{
    if (Input.touchCount > 0) // Check if there are any touch events happening
    {
        Touch touch = Input.GetTouch(0); // Get information about the first touch event

        switch (touch.phase)
        {
            case TouchPhase.Began:
                if (IsTouchedOnPlayer(touch.position)) // If touched on player, spawn a circle under them and return without doing anything else
                {
                    currentCircle = Instantiate(circlePrefab, transform.position, Quaternion.identity);
                    return;
                }
                break;

            case TouchPhase.Moved:
                if (currentCircle != null) // If there's already a circle spawned, move it to follow the finger movement
                {
                    Vector3 touchPos = Camera.main.ScreenToWorldPoint(touch.position); // Convert screen coordinates to world coordinates
                    touchPos.z = 0;
                    currentCircle.transform.position = touchPos;
                }
                break;

            case TouchPhase.Ended:
            case TouchPhase.Canceled:
                if (currentCircle != null)
                    Destroy(currentCircle);

                HandleTouchEndedOrCanceled(touch); // Handle end/cancelled touches by moving the player towards their final destination
                break;
        }
    }
}

private bool IsTouchedOnPlayer(Vector2 screenPosition)
{
    Vector2 worldPosition = Camera.main.ScreenToWorldPoint(screenPosition);
    Collider2D[] colliders = GetComponents<Collider2D>();
    foreach (var collider in colliders)
    {
        if (collider.OverlapPoint(worldPosition))
        {
            return true;
        }
    }
    return false;
}

void HandleTouchEndedOrCanceled(Touch touch)
{
    if (!IsTouchedOnPlayer(touch.position)) // If not touching the player at the end, set the target position to where they lifted their finger
    {
        Vector2 targetPos = Camera.main.ScreenToWorldPoint(touch.position);
        targetPosition = targetPos;

        if (currentCoroutine != null) // If already moving, stop the current coroutine so a new one can be started
            StopCoroutine(currentCoroutine);

        currentCoroutine = StartCoroutine(MoveToTarget()); // Start coroutine to move towards target position
    }
}

IEnumerator MoveToTarget()
{
    float moveSpeed = 5f; // Movement speed of 5 meters per second
    float bufferDistance = 0.1f; // Buffer distance of 0.1 meters before stopping movement
    Vector3 targetDirection;

    while (Vector3.Distance(transform.position, targetPosition) > bufferDistance) // Keep moving towards the target until within buffer distance
    {
        if (transform.position == targetPosition) // If already at the destination, exit coroutine early
            yield break;

        targetDirection = (targetPosition - transform.position).normalized; // Calculate direction to move in

        if (targetDirection.x > 0 && !facingRight) // Flip sprite if needed to face direction of movement
        {
            Flip();
        }
        else if (targetDirection.x < 0 && facingRight)
        {
            Flip();
        }

        if (Vector3.Distance(transform.position, targetPosition) < moveSpeed * Time.deltaTime) // If close enough to target that one more step would overshoot it, just set position to the target and exit
        {
            transform.position = targetPosition;
            yield break;
        }

        transform.position = Vector3.MoveTowards(transform.position, targetPosition, moveSpeed * Time.deltaTime); // Move towards the target

        yield return null; // Wait for next frame before continuing loop
    }
}

void Flip() // Flips the sprite horizontally (useful when changing direction)
{
    facingRight = !facingRight;

    Vector3 scale = transform.localScale;
    scale.x *= -1;
    transform.localScale = scale;
}

}