using GeometryTD.CustomUtility;
using GeometryTD.Definition;

namespace GeometryTD.UI
{
    public class RepoFormUseCase : IUIUseCase
    {
        private const int MaxParticipantCount = 4;
        private BackpackInventoryData _fallbackInventory;

        public RepoFormRawData CreateInitialModel()
        {
            BackpackInventoryData sample = GameEntry.PlayerInventory != null
                ? GameEntry.PlayerInventory.GetInventorySnapshot()
                : GetOrCreateFallbackInventory();
            return new RepoFormRawData
            {
                Inventory = sample
            };
        }

        public bool TryAssembleTower(long muzzleItemId, long bearingItemId, long baseItemId)
        {
            if (GameEntry.PlayerInventory == null)
            {
                return false;
            }

            return GameEntry.PlayerInventory.TryAssembleTower(
                muzzleItemId,
                bearingItemId,
                baseItemId,
                out _);
        }

        public bool TryAddParticipantTower(long towerItemId)
        {
            if (GameEntry.PlayerInventory == null)
            {
                BackpackInventoryData fallbackInventory = GetOrCreateFallbackInventory();
                return InventoryParticipantUtility.TryAddParticipantTower(
                    fallbackInventory,
                    towerItemId,
                    MaxParticipantCount);
            }

            return GameEntry.PlayerInventory.TryAddParticipantTower(towerItemId, 4);
        }

        public bool TryRemoveParticipantTower(long towerItemId)
        {
            if (GameEntry.PlayerInventory == null)
            {
                BackpackInventoryData fallbackInventory = GetOrCreateFallbackInventory();
                return InventoryParticipantUtility.TryRemoveParticipantTower(
                    fallbackInventory,
                    towerItemId,
                    MaxParticipantCount);
            }

            return GameEntry.PlayerInventory.TryRemoveParticipantTower(towerItemId);
        }

        private BackpackInventoryData GetOrCreateFallbackInventory()
        {
            _fallbackInventory ??= InventorySeedUtility.CreateSampleInventory();
            InventoryParticipantUtility.NormalizeParticipantState(_fallbackInventory, MaxParticipantCount);
            return _fallbackInventory;
        }
    }
}