using UnityEngine;
using UnityEngine.Rendering;
using INab.BetterFog.URP;

namespace Ashwild.Environment
{
    /// <summary>
    /// Ties INab Studio's Better Fog to the day/night cycle: every frame it copies the
    /// TimeOfDayManager's current sky colors into the Better Fog volume override so the fog
    /// warms at dawn/dusk and turns cool/dark at night along with the sky. This is the ONLY
    /// script that references the Better Fog asset — the manager itself stays fog-agnostic, so
    /// swapping the fog solution later only touches this file. Runs in edit mode so the fog
    /// tracks the time slider live.
    /// </summary>
    [ExecuteAlways]
    [DisallowMultipleComponent]
    [AddComponentMenu("GAME/Environment/Better Fog Day-Night Driver")]
    public class BetterFogDayNightDriver : MonoBehaviour
    {
        #region Serialized Fields

        [Tooltip("Global Volume whose profile holds a Better Fog override.")]
        [SerializeField] private Volume fogVolume;
        [Tooltip("Push the current horizon color into Better Fog's Fog Color.")]
        [SerializeField] private bool driveFogColor = true;
        [Tooltip("Push the current sun color into Better Fog's Sun Color (only visible when Better Fog's Sun Light is enabled).")]
        [SerializeField] private bool driveSunColor = true;

        #endregion

        #region State

        private BetterFogVolumeComponent fog;

        #endregion

        #region Unity Lifecycle

        /// <summary>
        /// Resolves the Better Fog override once so Update can drive it cheaply, and warns if the
        /// wiring is incomplete instead of silently doing nothing.
        /// </summary>
        private void OnEnable()
        {
            ResolveFog();
        }

        /// <summary>
        /// Copies the manager's current palette into the fog override. No-op until both the fog
        /// volume and the manager exist, re-resolving the override if it was lost (profile swap).
        /// </summary>
        private void Update()
        {
            if (fog == null && !ResolveFog()) return;
            if (TimeOfDayManager.Instance == null) return;

            if (driveFogColor)
            {
                fog._FogColor.overrideState = true;
                fog._FogColor.value = TimeOfDayManager.Instance.CurrentHorizonColor;
            }

            if (driveSunColor)
            {
                fog._SunColor.overrideState = true;
                fog._SunColor.value = TimeOfDayManager.Instance.CurrentSunColor;
            }
        }

        #endregion

        #region Internal Helpers

        /// <summary>
        /// Fetches the Better Fog override from the assigned volume's profile, logging a clear
        /// error when it is missing so the setup mistake is obvious. Returns true on success.
        /// </summary>
        private bool ResolveFog()
        {
            if (fogVolume == null)
            {
                Debug.LogError($"[BetterFogDayNightDriver] '{name}' has no Fog Volume assigned.", this);
                return false;
            }

            if (fogVolume.profile == null || !fogVolume.profile.TryGet(out fog))
            {
                Debug.LogError($"[BetterFogDayNightDriver] '{name}' volume profile has no Better Fog override.", this);
                return false;
            }

            return true;
        }

        #endregion
    }
}