using System.Collections.Generic;
using ProjectM.Simulation;
using Unity.Collections;
using Unity.Entities;
using Unity.Mathematics;
using UnityEngine;

namespace ProjectM.Authoring
{
    /// <summary>
    /// Bakes the designer-authored ability + character definitions into a single AbilityDatabase blob
    /// singleton (immutable, shared, Burst-fast) plus a companion AbilityPrefabElement buffer holding the
    /// per-ability projectile ghost prefab entity refs (entity refs cannot live in a blob). Place ONE of
    /// these in the gameplay subscene; it streams identically into the client and server worlds (config,
    /// not replicated). DependsOn each definition so a value change in an SO re-bakes the blob.
    /// </summary>
    public class AbilityDatabaseAuthoring : MonoBehaviour
    {
        [Tooltip("All ability definitions available in the game. Indexed at runtime by AbilityId.")]
        public List<AbilityDefinition> Abilities = new List<AbilityDefinition>();

        [Tooltip("All character-stats definitions. Indexed at runtime by CharacterId.")]
        public List<CharacterStatsDefinition> Characters = new List<CharacterStatsDefinition>();

        private class DatabaseBaker : Baker<AbilityDatabaseAuthoring>
        {
            public override void Bake(AbilityDatabaseAuthoring authoring)
            {
                var entity = GetEntity(TransformUsageFlags.None);

                int abilityCount = authoring.Abilities != null ? authoring.Abilities.Count : 0;
                int charCount = authoring.Characters != null ? authoring.Characters.Count : 0;

                var builder = new BlobBuilder(Allocator.Temp);
                ref var root = ref builder.ConstructRoot<AbilityDatabaseBlob>();

                var abilityArray = builder.Allocate(ref root.Abilities, abilityCount);
                for (int i = 0; i < abilityCount; i++)
                {
                    var def = authoring.Abilities[i];
                    if (def == null) { abilityArray[i] = default; continue; }
                    DependsOn(def);
                    abilityArray[i] = new AbilityDefBlob
                    {
                        Id = (byte)def.Id,
                        Damage = def.Damage,
                        ProjectileSpeed = def.ProjectileSpeed,
                        Range = def.Range,
                        AutoTargetRange = def.AutoTargetRange,
                        AutoTargetConeRadians = math.radians(def.AutoTargetConeDegrees),
                        CooldownTicks = def.CooldownTicks,
                        Name = def.DisplayName,
                    };
                }

                var charArray = builder.Allocate(ref root.Characters, charCount);
                for (int i = 0; i < charCount; i++)
                {
                    var def = authoring.Characters[i];
                    if (def == null) { charArray[i] = default; continue; }
                    DependsOn(def);
                    charArray[i] = new CharacterStatsBlob
                    {
                        Id = (byte)def.Id,
                        MoveSpeed = def.MoveSpeed,
                        TurnRateRadiansPerSec = math.radians(def.TurnRateDegreesPerSec),
                        MaxHealth = def.MaxHealth,
                        Name = def.DisplayName,
                    };
                }

                var blob = builder.CreateBlobAssetReference<AbilityDatabaseBlob>(Allocator.Persistent);
                builder.Dispose();
                AddBlobAsset(ref blob, out _);
                AddComponent(entity, new AbilityDatabase { Value = blob });

                // Companion entity-ref buffer: per-ability projectile ghost prefab (resolved via GetEntity).
                var prefabBuffer = AddBuffer<AbilityPrefabElement>(entity);
                for (int i = 0; i < abilityCount; i++)
                {
                    var def = authoring.Abilities[i];
                    if (def == null || def.ProjectilePrefab == null) continue;
                    prefabBuffer.Add(new AbilityPrefabElement
                    {
                        Id = (byte)def.Id,
                        Prefab = GetEntity(def.ProjectilePrefab, TransformUsageFlags.Dynamic),
                    });
                }
            }
        }
    }
}