using System;
using System.Collections.Generic;
using GeometryTD.CustomEvent;
using GeometryTD.Definition;
using GameFramework.Event;
using GeometryTD.CustomUtility;
using UnityEngine;
using UnityGameFramework.Runtime;

namespace GeometryTD.UI
{
    public class RepoFormController : UIFormControllerCommonBase<RepoFormContext, RepoForm>
    {
        private RepoFormUseCase _useCase;
        private readonly Dictionary<long, RepoItemContext> _itemContextMap = new Dictionary<long, RepoItemContext>();
        private readonly Dictionary<long, ItemDescSeed> _itemDescSeedMap = new Dictionary<long, ItemDescSeed>();

        private sealed class ItemDescSeed
        {
            public string Title;
            public string TypeText;
            public string Description;
            public TagType[] Tags;
        }

        protected override UIFormType UIFormTypeId => UIFormType.RepoForm;

        protected override void RefreshUI(RepoForm form, RepoFormContext context)
        {
            form.RefreshUI(context);
        }

        protected override void SubscribeCustomEvents()
        {
            GameEntry.Event.Subscribe(RepoItemDetailRequestedEventArgs.EventId, OnRepoItemDetailRequested);
            GameEntry.Event.Subscribe(RepoItemDragEndedEventArgs.EventId, OnRepoItemDragEnded);
            GameEntry.Event.Subscribe(CombineSlotClickedEventArgs.EventId, OnCombineSlotClicked);
            GameEntry.Event.Subscribe(RepoCombineRequestedEventArgs.EventId, OnRepoCombineRequested);
            GameEntry.Event.Subscribe(RepoFormReturnEventArgs.EventId, OnRepoFormReturn);
        }

        protected override void UnsubscribeCustomEvents()
        {
            GameEntry.Event.Unsubscribe(RepoItemDetailRequestedEventArgs.EventId, OnRepoItemDetailRequested);
            GameEntry.Event.Unsubscribe(RepoItemDragEndedEventArgs.EventId, OnRepoItemDragEnded);
            GameEntry.Event.Unsubscribe(CombineSlotClickedEventArgs.EventId, OnCombineSlotClicked);
            GameEntry.Event.Unsubscribe(RepoCombineRequestedEventArgs.EventId, OnRepoCombineRequested);
            GameEntry.Event.Unsubscribe(RepoFormReturnEventArgs.EventId, OnRepoFormReturn);
        }

        public override int? OpenUI(object userData = null)
        {
            if (userData is RepoFormContext repoFormContext)
            {
                return OpenUIInternal(repoFormContext);
            }

            if (userData is RepoFormRawData rawDataFromUserData)
            {
                return OpenUI(rawDataFromUserData);
            }

            if (userData != null)
            {
                Log.Warning("RepoFormController.OpenUI() userData type is invalid.");
                return null;
            }

            if (_useCase == null)
            {
                Log.Error("RepoFormController.OpenUI() useCase is null.");
                return null;
            }

            RepoFormRawData rawData = _useCase.CreateInitialModel();
            return OpenUI(rawData);
        }

        public int? OpenUI(RepoFormRawData rawData)
        {
            RepoFormContext context = BuildContext(rawData);
            return OpenUIInternal(context);
        }

        public override void BindUseCase(IUIUseCase useCase)
        {
            if (!(useCase is RepoFormUseCase repoFormUseCase))
            {
                Log.Error("RepoFormController.BindUseCase() useCase is invalid.");
                return;
            }

            _useCase = repoFormUseCase;
        }

        private RepoFormContext BuildContext(RepoFormRawData rawData)
        {
            _itemContextMap.Clear();
            _itemDescSeedMap.Clear();
            if (rawData?.Inventory == null)
            {
                return null;
            }

            List<RepoItemContext> items = new List<RepoItemContext>();

            if (rawData.Inventory.Towers != null)
            {
                foreach (TowerItemData tower in rawData.Inventory.Towers)
                {
                    if (tower == null)
                    {
                        continue;
                    }

                    AddItemContext(items, new RepoItemContext
                    {
                        InstanceId = tower.InstanceId,
                        CanDrag = true,
                        ComponentSlotType = TowerCompSlotType.None,
                        IconAreaContext = BuildIconAreaContext(tower)
                    });
                    AddItemDescSeed(
                        tower.InstanceId,
                        tower.Name,
                        "Tower",
                        ItemDescUtility.BuildTowerDesc(tower.Stats) ?? string.Empty,
                        tower.Stats != null ? tower.Stats.Tags : null);
                }
            }

            if (rawData.Inventory.MuzzleComponents != null)
            {
                foreach (MuzzleCompItemData item in rawData.Inventory.MuzzleComponents)
                {
                    if (item == null || item.IsAssembledIntoTower)
                    {
                        continue;
                    }

                    AddItemContext(items, new RepoItemContext
                    {
                        InstanceId = item.InstanceId,
                        CanDrag = true,
                        ComponentSlotType = TowerCompSlotType.Muzzle,
                        IconAreaContext = BuildIconAreaContext(item)
                    });
                    AddItemDescSeed(
                        item.InstanceId,
                        item.Name,
                        BuildComponentTypeText(item.SlotType),
                        ItemDescUtility.BuildMuzzleDesc(item) ?? string.Empty,
                        item.Tags);
                }
            }

            if (rawData.Inventory.BearingComponents != null)
            {
                foreach (BearingCompItemData item in rawData.Inventory.BearingComponents)
                {
                    if (item == null || item.IsAssembledIntoTower)
                    {
                        continue;
                    }

                    AddItemContext(items, new RepoItemContext
                    {
                        InstanceId = item.InstanceId,
                        CanDrag = true,
                        ComponentSlotType = TowerCompSlotType.Bearing,
                        IconAreaContext = BuildIconAreaContext(item)
                    });
                    AddItemDescSeed(
                        item.InstanceId,
                        item.Name,
                        BuildComponentTypeText(item.SlotType),
                        ItemDescUtility.BuildBearingDesc(item) ?? string.Empty,
                        item.Tags);
                }
            }

            if (rawData.Inventory.BaseComponents != null)
            {
                foreach (BaseCompItemData item in rawData.Inventory.BaseComponents)
                {
                    if (item == null || item.IsAssembledIntoTower)
                    {
                        continue;
                    }

                    AddItemContext(items, new RepoItemContext
                    {
                        InstanceId = item.InstanceId,
                        CanDrag = true,
                        ComponentSlotType = TowerCompSlotType.Base,
                        IconAreaContext = BuildIconAreaContext(item)
                    });
                    AddItemDescSeed(
                        item.InstanceId,
                        item.Name,
                        BuildComponentTypeText(item.SlotType),
                        ItemDescUtility.BuildBaseDesc(item) ?? string.Empty,
                        item.Tags);
                }
            }

            return new RepoFormContext
            {
                CombineAreaContext = new CombineAreaContext(),
                CompAreaContext = new CompAreaContext
                {
                    Items = items.ToArray()
                }
            };
        }

        private void AddItemContext(List<RepoItemContext> items, RepoItemContext itemContext)
        {
            if (itemContext == null)
            {
                return;
            }

            items.Add(itemContext);
            _itemContextMap[itemContext.InstanceId] = itemContext;
        }

        private void AddItemDescSeed(long itemId, string title, string typeText, string description, TagType[] tags)
        {
            if (itemId <= 0)
            {
                return;
            }

            _itemDescSeedMap[itemId] = new ItemDescSeed
            {
                Title = string.IsNullOrWhiteSpace(title) ? $"Item {itemId}" : title,
                TypeText = typeText ?? string.Empty,
                Description = description ?? string.Empty,
                Tags = CloneTags(tags)
            };
        }

        private static TagType[] CloneTags(TagType[] tags)
        {
            return tags != null ? (TagType[])tags.Clone() : Array.Empty<TagType>();
        }

        private static string BuildComponentTypeText(TowerCompSlotType slotType)
        {
            return slotType switch
            {
                TowerCompSlotType.Muzzle => "Muzzle Component",
                TowerCompSlotType.Bearing => "Bearing Component",
                TowerCompSlotType.Base => "Base Component",
                TowerCompSlotType.Accessory => "Accessory",
                _ => "Component"
            };
        }

        private static IconAreaContext BuildIconAreaContext(TowerItemData tower)
        {
            if (tower == null)
            {
                return new IconAreaContext
                {
                    ComponentSlotType = TowerCompSlotType.None,
                    Rarity = RarityType.None,
                    Color = Color.white,
                    Icon = null
                };
            }

            return new IconAreaContext
            {
                ComponentSlotType = TowerCompSlotType.None,
                Rarity = tower.Rarity,
                Color = IconColorGenerator.GenerateForTower(tower),
                Icon = null
            };
        }

        private static IconAreaContext BuildIconAreaContext(TowerCompItemData item)
        {
            if (item == null)
            {
                return new IconAreaContext
                {
                    ComponentSlotType = TowerCompSlotType.None,
                    Rarity = RarityType.None,
                    Color = Color.white,
                    Icon = null
                };
            }

            return new IconAreaContext
            {
                ComponentSlotType = item.SlotType,
                Rarity = item.Rarity,
                Color = IconColorGenerator.GenerateForComponent(item),
                Icon = null
            };
        }

        #region Event Handlers

        private void OnRepoItemDetailRequested(object sender, GameEventArgs e)
        {
            if (!IsEventFromCurrentForm(sender))
            {
                return;
            }

            if (!(e is RepoItemDetailRequestedEventArgs args))
            {
                return;
            }

            if (!_itemDescSeedMap.TryGetValue(args.ItemId, out ItemDescSeed seed))
            {
                return;
            }

            GameEntry.UIRouter.OpenUI(UIFormType.ItemDescForm, new ItemDescFormRawData
            {
                Title = seed.Title,
                TypeText = seed.TypeText,
                Description = seed.Description ?? string.Empty,
                Price = 0,
                TargetPos = args.TargetPos,
                Tags = CloneTags(seed.Tags)
            });
        }

        private void OnRepoItemDragEnded(object sender, GameEventArgs e)
        {
            if (!IsEventFromCurrentForm(sender))
            {
                return;
            }

            if (!(e is RepoItemDragEndedEventArgs args))
            {
                return;
            }

            if (Form == null || !_itemContextMap.ContainsKey(args.ItemId))
            {
                return;
            }

            Form.SetRepoItemSelected(args.ItemId, args.Assigned);
        }

        private void OnCombineSlotClicked(object sender, GameEventArgs e)
        {
            if (!IsEventFromCurrentForm(sender))
            {
                return;
            }

            if (!(e is CombineSlotClickedEventArgs args))
            {
                return;
            }

            if (Form == null)
            {
                return;
            }

            if (Form.TryClearCombineSlot(args.SlotIndex, out long removedItemId) && removedItemId > 0)
            {
                Form.SetRepoItemSelected(removedItemId, false);
            }
        }

        private void OnRepoFormReturn(object sender, GameEventArgs e)
        {
            if (!IsEventFromCurrentForm(sender) || !(e is RepoFormReturnEventArgs))
            {
                return;
            }

            if (Form == null)
            {
                return;
            }
            
            this.CloseUI();
        }

        private void OnRepoCombineRequested(object sender, GameEventArgs e)
        {
            if (!IsEventFromCurrentForm(sender))
            {
                return;
            }

            if (!(e is RepoCombineRequestedEventArgs args))
            {
                return;
            }

            if (_useCase == null || Form == null)
            {
                return;
            }

            if (!_useCase.TryAssembleTower(args.MuzzleItemId, args.BearingItemId, args.BaseItemId))
            {
                return;
            }

            RepoFormRawData latestRawData = _useCase.CreateInitialModel();
            RepoFormContext latestContext = BuildContext(latestRawData);
            if (latestContext != null)
            {
                Form.RefreshUI(latestContext);
            }
        }

        private bool IsEventFromCurrentForm(object sender)
        {
            if (Form == null)
            {
                return false;
            }

            if (ReferenceEquals(sender, Form))
            {
                return true;
            }

            if (sender is Component component)
            {
                RepoForm ownerForm = component.GetComponentInParent<RepoForm>();
                return ownerForm == Form;
            }

            return false;
        }

        #endregion
    }
}