using System;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using ReLogic.Content;
using Terraria;
using Terraria.GameContent;
using Terraria.ID;
using Terraria.ModLoader;

namespace ForgottenWawiTech.Content.Items.Global
{
    // Visual effects for items that use the Singularity rarity
    public class SingularityRarityVisuals : GlobalItem
    {
        public override bool InstancePerEntity => false;

        private static int SingularityRarityId => ModContent.RarityType<Content.Rarities.SingularityItem>();

        private static bool IsSingularity(Item item) => item.rare == SingularityRarityId;

        private static Color GetSingularityColor()
        {
            // Reuse the rarity's animated color so visuals stay in sync
            var rarity = ModContent.GetInstance<Content.Rarities.SingularityItem>();
            return rarity.RarityColor;
        }

        private static float GetBreathing(float hz, float minScale = 0.85f, float maxScale = 1.15f)
        {
            float t = Main.GlobalTimeWrappedHourly * hz * MathHelper.TwoPi;
            float s = (float)(Math.Sin(t) * 0.5 + 0.5); // 0..1
            return MathHelper.Lerp(minScale, maxScale, s);
        }

        public override void PostDrawInInventory(Item item, SpriteBatch spriteBatch, Vector2 position, Rectangle frame, Color drawColor, Color itemColor, Vector2 origin, float scale)
        {
            if (!IsSingularity(item))
                return;

            Texture2D texture = TextureAssets.Item[item.type].Value;

            // Subtle chromatic aberration: red and blue edge offsets
            float aberrPixels = 1f;
            Color redTint = new Color(255, 60, 60) * 0.25f;
            Color blueTint = new Color(60, 60, 255) * 0.25f;

            spriteBatch.Draw(texture, position + new Vector2(aberrPixels, 0f), frame, redTint, 0f, origin, scale, SpriteEffects.None, 0f);
            spriteBatch.Draw(texture, position + new Vector2(-aberrPixels, 0f), frame, blueTint, 0f, origin, scale, SpriteEffects.None, 0f);

            // Optional glow overlay if a _Glow texture exists
            if (TryGetGlowTexture(item, out var glowTex))
            {
                Color glowColor = GetSingularityColor();
                float breathe = GetBreathing(0.5f, 0.9f, 1.2f);
                spriteBatch.Draw(glowTex, position, frame, glowColor * 0.6f, 0f, origin, scale * breathe, SpriteEffects.None, 0f);
            }
        }

        public override bool PreDrawInWorld(Item item, SpriteBatch spriteBatch, Color lightColor, Color alphaColor, ref float rotation, ref float scale, int whoAmI)
        {
            if (!IsSingularity(item))
                return true; // not ours, let vanilla draw

            Texture2D texture = TextureAssets.Item[item.type].Value;
            Rectangle frame = Main.itemAnimations[item.type] != null
                ? Main.itemAnimations[item.type].GetFrame(texture)
                : texture.Frame();

            Vector2 drawPos = item.Center - Main.screenPosition;
            Vector2 origin = frame.Size() / 2f;

            // Sync light with rarity color (subtle)
            Color pulse = GetSingularityColor();
            Lighting.AddLight(item.Center, pulse.ToVector3() * 0.35f);

            // Subtle chromatic aberration edges
            float aberrPixels = 1f;
            Color redTint = new Color(255, 60, 60) * 0.20f;
            Color blueTint = new Color(60, 60, 255) * 0.20f;

            spriteBatch.Draw(texture, drawPos + new Vector2(aberrPixels, 0f), frame, redTint, rotation, origin, scale, SpriteEffects.None, 0f);
            spriteBatch.Draw(texture, drawPos + new Vector2(-aberrPixels, 0f), frame, blueTint, rotation, origin, scale, SpriteEffects.None, 0f);

            // Optional glow overlay if a _Glow texture exists
            if (TryGetGlowTexture(item, out var glowTex))
            {
                float breathe = GetBreathing(0.5f, 0.9f, 1.15f);
                spriteBatch.Draw(glowTex, drawPos, frame, pulse * 0.7f, rotation, origin, scale * breathe, SpriteEffects.None, 0f);
            }

            return true; // continue with default draw
        }

        public override void HoldItem(Item item, Player player)
        {
            if (!IsSingularity(item))
                return;

            Color pulse = GetSingularityColor();
            // Add light at the player's hand
            Lighting.AddLight(player.MountedCenter, pulse.ToVector3() * 0.45f);

            // Faint rotating dust ring to simulate an event horizon while held
            int points = 8;
            float radius = 10f;
            float speed = 2.2f; // rotations per second
            float t = Main.GlobalTimeWrappedHourly * speed * MathHelper.TwoPi;
            for (int i = 0; i < points; i++)
            {
                float angle = t + (i / (float)points) * MathHelper.TwoPi;
                Vector2 pos = player.MountedCenter + angle.ToRotationVector2() * radius;
                Dust d = Dust.NewDustPerfect(pos, DustID.PurpleTorch, Vector2.Zero, 150, pulse, 0.9f);
                if (d != null)
                {
                    d.noGravity = true;
                    d.velocity = Vector2.Zero;
                }
            }
        }

        private static bool TryGetGlowTexture(Item item, out Texture2D texture)
        {
            texture = null;
            // Only attempt for modded items that likely follow the _Glow convention
            if (item.ModItem == null)
                return false;

            string path = item.ModItem.Texture + "_Glow";
            if (ModContent.HasAsset(path))
            {
                Asset<Texture2D> asset = ModContent.Request<Texture2D>(path, AssetRequestMode.AsyncLoad);
                if (asset.IsLoaded)
                {
                    texture = asset.Value;
                    return true;
                }
            }
            return false;
        }
    }
}