using System;
using System.Collections.Generic;
using UnityEngine;

namespace NightclubArcadia.Skills
{
    [CreateAssetMenu(menuName = "Nightclub Arcadia/Skill Database", fileName = "SkillDatabase")]
    public sealed class SkillDatabase : ScriptableObject
    {
        [SerializeField] List<SkillDefinition> skills = new List<SkillDefinition>();

        Dictionary<string, SkillDefinition> _lookup;

        public IReadOnlyList<SkillDefinition> All => skills;

        public bool TryGet(string skillId, out SkillDefinition def)
        {
            EnsureLookup();
            if (string.IsNullOrEmpty(skillId))
            {
                def = null;
                return false;
            }

            return _lookup.TryGetValue(skillId, out def);
        }

        void EnsureLookup()
        {
            if (_lookup != null)
            {
                return;
            }

            _lookup = new Dictionary<string, SkillDefinition>(StringComparer.OrdinalIgnoreCase);
            if (skills == null)
            {
                return;
            }

            foreach (var skill in skills)
            {
                if (skill == null || string.IsNullOrEmpty(skill.Id))
                {
                    continue;
                }

                _lookup[skill.Id] = skill;
            }
        }

        void OnValidate()
        {
            _lookup = null;
            if (skills == null)
            {
                return;
            }

            var seen = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
            foreach (var skill in skills)
            {
                if (skill == null)
                {
                    Debug.LogError($"[{nameof(SkillDatabase)}] Null skill entry in {name}.", this);
                    continue;
                }

                if (string.IsNullOrEmpty(skill.Id))
                {
                    Debug.LogError($"[{nameof(SkillDatabase)}] Skill '{skill.name}' has an empty Id.", this);
                    continue;
                }

                if (!seen.Add(skill.Id))
                {
                    Debug.LogError($"[{nameof(SkillDatabase)}] Duplicate skill Id '{skill.Id}'.", this);
                }
            }
        }

#if UNITY_EDITOR
        public void EditorSetSkills(List<SkillDefinition> newSkills)
        {
            skills = newSkills ?? new List<SkillDefinition>();
            _lookup = null;
        }
#endif
    }
}