using UnityEngine;
using DepthsOfGreed.HandbookUI;

public class Turret : MonoBehaviour
{
    [Header("Tower Data")]
    [SerializeField]
    private HandbookTowerEntry towerData;

    [Header("Turret Setup")]
    [SerializeField]
    private Transform turret;

    [SerializeField]
    private Transform tip;

    [SerializeField]
    private float rotationSpeed = 360f;

    [Header("Projectile Setup")]
    [SerializeField]
    private GameObject bulletPrefab;

    [SerializeField]
    private float bulletSpeed = 8f;

    private CombatDefinition combatStats;

    private float nextAttackTime;

    private Enemy currentTarget;

    private void Start()
    {
        if (towerData == null)
        {
            Debug.LogError(
                "TowerShooting: Kein HandbookTowerEntry zugewiesen!",
                this
            );

            enabled = false;
            return;
        }

        if (turret == null || tip == null || bulletPrefab == null)
        {
            Debug.LogError(
                "TowerShooting: Turret, Tip oder Bullet Prefab fehlt!",
                this
            );

            enabled = false;
            return;
        }

        combatStats = towerData.CreateCombatSnapshot(0);
    }

    private void Update()
    {
        if (combatStats == null)
            return;

        // Ziel innerhalb der Reichweite suchen.
        currentTarget = FindTarget();

        if (currentTarget != null)
        {
            RotateTowardsTarget();
            TryShoot();
        }
        else
        {
            // Zur ursprünglichen Ausrichtung zurückkehren.
            RotateTowardsOrigin();
        }
    }

    private Enemy FindTarget()
    {
        Enemy[] enemies =
            FindObjectsByType<Enemy>(
                FindObjectsSortMode.None
            );

        Enemy closestEnemy = null;

        float closestDistance = float.MaxValue;

        float rangeSquared =
            combatStats.range * combatStats.range;

        foreach (Enemy enemy in enemies)
        {
            if (enemy == null || enemy.IsDead)
                continue;

            Vector2 difference =
                enemy.transform.position - transform.position;

            float distanceSquared = difference.sqrMagnitude;

            if (distanceSquared > rangeSquared)
                continue;

            if (distanceSquared < closestDistance)
            {
                closestDistance = distanceSquared;
                closestEnemy = enemy;
            }
        }

        return closestEnemy;
    }

    private void RotateTowardsTarget()
    {
        Vector3 worldDirection =
            currentTarget.transform.position - turret.position;

        // Richtung in den lokalen Raum der Turmbasis umwandeln.
        Vector3 localDirection =
            turret.parent != null
                ? turret.parent.InverseTransformDirection(worldDirection)
                : worldDirection;

        float targetAngle =
            Mathf.Atan2(localDirection.y, localDirection.x)
            * Mathf.Rad2Deg - 90f;

        Quaternion targetRotation =
            Quaternion.Euler(0f, 0f, targetAngle);

        turret.localRotation = Quaternion.RotateTowards(
            turret.localRotation,
            targetRotation,
            rotationSpeed * Time.deltaTime
        );
    }

    private void RotateTowardsOrigin()
    {
        turret.localRotation = Quaternion.RotateTowards(
            turret.localRotation,
            Quaternion.identity,
            rotationSpeed * Time.deltaTime
        );
    }

    private void TryShoot()
    {
        if (combatStats.attacksPerSecond <= 0f)
            return;

        if (Time.time < nextAttackTime)
            return;

        Shoot();

        float attackInterval =
            1f / combatStats.attacksPerSecond;

        nextAttackTime = Time.time + attackInterval;
    }

    private void Shoot()
    {
        GameObject bulletObject = Instantiate(
            bulletPrefab,
            tip.position,
            tip.rotation
        );

        Bullet bullet =
            bulletObject.GetComponent<Bullet>();

        if (bullet == null)
        {
            Debug.LogError(
                "TowerShooting: Bullet Prefab besitzt kein TowerBullet-Skript!",
                bulletObject
            );

            Destroy(bulletObject);
            return;
        }

        bullet.Initialize(
            tip.up,
            bulletSpeed,
            combatStats.damagePerHit,
            combatStats.range
        );
    }

    private void OnDrawGizmosSelected()
    {
        if (towerData == null)
            return;

        Gizmos.color = Color.red;

        Gizmos.DrawWireSphere(
            transform.position,
            towerData.combat.range
        );
    }
}