using UnityEngine;

// 슬라이딩 장애물 패턴이 켜질 때마다 매달린 장애물 위치를 섞는다.
public class SlideObstaclePattern : MonoBehaviour
{
    public enum SlideLayout {
        Random,
        LeftPair,
        CenterPair,
        RightPair,
        WidePair
    }

    public Transform[] obstacles; // 위치를 바꿀 고공 장애물들
    public float[] xPositions = { -1.65f, -0.55f, 0.55f, 1.65f }; // 선택 가능한 로컬 x 위치
    public float minSpacing = 1.5f; // 두 장애물 사이의 최소 간격
    public SlideLayout layout = SlideLayout.Random; // 패턴 스포너가 지정하는 슬라이딩 장애물 배치

    private void OnEnable()
    {
        if(obstacles == null || obstacles.Length == 0 || xPositions == null || xPositions.Length == 0)
        {
            return;
        }

        if(layout != SlideLayout.Random)
        {
            PlaceLayout(layout);
            return;
        }

        int firstIndex = Random.Range(0, xPositions.Length);

        if(obstacles.Length == 1 || xPositions.Length == 1)
        {
            PlaceObstacle(obstacles[0], xPositions[firstIndex]);
            return;
        }

        int secondIndex = PickSecondIndex(firstIndex);

        float leftX = xPositions[firstIndex];
        float rightX = xPositions[secondIndex];

        if(leftX > rightX)
        {
            float temp = leftX;
            leftX = rightX;
            rightX = temp;
        }

        PlaceObstacle(obstacles[0], leftX);
        PlaceObstacle(obstacles[1], rightX);
    }

    public void ConfigureLayout(SlideLayout nextLayout)
    {
        layout = nextLayout;
    }

    private void PlaceLayout(SlideLayout fixedLayout)
    {
        if(obstacles.Length == 1)
        {
            PlaceObstacle(obstacles[0], PickSingleX(fixedLayout));
            return;
        }

        float leftX;
        float rightX;

        switch(fixedLayout)
        {
            case SlideLayout.LeftPair:
                leftX = xPositions[0];
                rightX = xPositions[Mathf.Min(2, xPositions.Length - 1)];
                break;
            case SlideLayout.CenterPair:
                leftX = xPositions[Mathf.Min(1, xPositions.Length - 1)];
                rightX = xPositions[Mathf.Min(2, xPositions.Length - 1)];
                break;
            case SlideLayout.RightPair:
                leftX = xPositions[Mathf.Max(0, xPositions.Length - 3)];
                rightX = xPositions[xPositions.Length - 1];
                break;
            case SlideLayout.WidePair:
            default:
                leftX = xPositions[0];
                rightX = xPositions[xPositions.Length - 1];
                break;
        }

        if(Mathf.Approximately(leftX, rightX) && xPositions.Length > 1)
        {
            leftX = xPositions[0];
            rightX = xPositions[xPositions.Length - 1];
        }

        if(leftX > rightX)
        {
            float temp = leftX;
            leftX = rightX;
            rightX = temp;
        }

        PlaceObstacle(obstacles[0], leftX);
        PlaceObstacle(obstacles[1], rightX);
    }

    private float PickSingleX(SlideLayout fixedLayout)
    {
        switch(fixedLayout)
        {
            case SlideLayout.LeftPair:
                return xPositions[0];
            case SlideLayout.CenterPair:
                return xPositions[Mathf.Min(1, xPositions.Length - 1)];
            case SlideLayout.RightPair:
                return xPositions[xPositions.Length - 1];
            case SlideLayout.WidePair:
            default:
                return xPositions[Mathf.Min(2, xPositions.Length - 1)];
        }
    }

    private int PickSecondIndex(int firstIndex)
    {
        for(int i = 0; i < 12; i++)
        {
            int candidateIndex = Random.Range(0, xPositions.Length);

            if(candidateIndex != firstIndex && Mathf.Abs(xPositions[candidateIndex] - xPositions[firstIndex]) >= minSpacing)
            {
                return candidateIndex;
            }
        }

        int bestIndex = firstIndex;
        float bestDistance = 0f;

        for(int i = 0; i < xPositions.Length; i++)
        {
            float distance = Mathf.Abs(xPositions[i] - xPositions[firstIndex]);

            if(distance > bestDistance)
            {
                bestDistance = distance;
                bestIndex = i;
            }
        }

        return bestIndex;
    }

    private void PlaceObstacle(Transform obstacle, float xPosition)
    {
        if(obstacle == null)
        {
            return;
        }

        Vector3 localPosition = obstacle.localPosition;
        localPosition.x = xPosition;
        obstacle.localPosition = localPosition;
    }
}