using System;
using System.Collections.Generic;
using GeometryTD.CustomUtility;
using GeometryTD.Definition;
using GeometryTD.Factory;

namespace GeometryTD.Procedure
{
    public enum RunNodeType
    {
        None = 0,
        Combat = 1,
        Event = 2,
        Shop = 3,
        BossCombat = 4
    }

    public enum RunNodeStatus
    {
        Locked = 0,
        Available = 1,
        Completed = 2,
        Exception = 3,
        Skipped = 4
    }

    public enum RunNodeCompletionStatus
    {
        None = 0,
        Completed = 1,
        Exception = 2
    }

    [Serializable]
    public sealed class RunNodeSeed
    {
        public int NodeId { get; set; }
        public RunNodeType NodeType { get; set; }
        public LevelThemeType ThemeType { get; set; }
        public int LinkedLevelId { get; set; }
        public int SequenceIndex { get; set; } = -1;
    }

    [Serializable]
    public sealed class RunNodeState
    {
        public int NodeId { get; internal set; }
        public RunNodeType NodeType { get; internal set; }
        public LevelThemeType ThemeType { get; internal set; }
        public int LinkedLevelId { get; internal set; }
        public RunNodeStatus Status { get; internal set; }
        public int SequenceIndex { get; internal set; }

        internal RunNodeState Clone()
        {
            return new RunNodeState
            {
                NodeId = NodeId,
                NodeType = NodeType,
                ThemeType = ThemeType,
                LinkedLevelId = LinkedLevelId,
                Status = Status,
                SequenceIndex = SequenceIndex
            };
        }
    }

    [Serializable]
    public sealed class RunItemState
    {
        public int ItemId { get; set; }
        public int StackCount { get; set; }

        internal RunItemState Clone()
        {
            return new RunItemState
            {
                ItemId = ItemId,
                StackCount = StackCount
            };
        }
    }

    [Serializable]
    public sealed class RunNodeExecutionContext
    {
        public string RunId { get; set; }
        public int RunSeed { get; set; }
        public int NodeId { get; set; }
        public RunNodeType NodeType { get; set; }
        public int SequenceIndex { get; set; }
        public LevelThemeType ThemeType { get; set; }
        public int ThemeStageIndex { get; set; }
        public List<LevelThemeType> CurrentThemePool { get; set; } = new List<LevelThemeType>();
        public List<LevelThemeType> ThemeHistory { get; set; } = new List<LevelThemeType>();
        public int CurrentNodeContinueChallengeLayer { get; set; }
        public List<RunItemState> RunItems { get; set; } = new List<RunItemState>();

        internal RunNodeExecutionContext Clone()
        {
            return new RunNodeExecutionContext
            {
                RunId = RunId,
                RunSeed = RunSeed,
                NodeId = NodeId,
                NodeType = NodeType,
                SequenceIndex = SequenceIndex,
                ThemeType = ThemeType,
                ThemeStageIndex = ThemeStageIndex,
                CurrentThemePool = RunStateCloneUtility.CloneThemeList(CurrentThemePool),
                ThemeHistory = RunStateCloneUtility.CloneThemeList(ThemeHistory),
                CurrentNodeContinueChallengeLayer = CurrentNodeContinueChallengeLayer,
                RunItems = RunStateCloneUtility.CloneRunItems(RunItems)
            };
        }

        public RunNodeCompletionSnapshot CreateCompletionSnapshot(BackpackInventoryData inventorySnapshot)
        {
            return new RunNodeCompletionSnapshot
            {
                InventorySnapshot = InventoryCloneUtility.CloneInventory(inventorySnapshot),
                ThemeType = ThemeType,
                ThemeStageIndex = ThemeStageIndex,
                CurrentThemePool = RunStateCloneUtility.CloneThemeList(CurrentThemePool),
                ThemeHistory = RunStateCloneUtility.CloneThemeList(ThemeHistory),
                CurrentNodeContinueChallengeLayer = CurrentNodeContinueChallengeLayer,
                RunItems = RunStateCloneUtility.CloneRunItems(RunItems)
            };
        }
    }

    [Serializable]
    public sealed class RunNodeCompletionSnapshot
    {
        public BackpackInventoryData InventorySnapshot { get; set; }
        public LevelThemeType ThemeType { get; set; }
        public int ThemeStageIndex { get; set; }
        public List<LevelThemeType> CurrentThemePool { get; set; } = new List<LevelThemeType>();
        public List<LevelThemeType> ThemeHistory { get; set; } = new List<LevelThemeType>();
        public int CurrentNodeContinueChallengeLayer { get; set; }
        public List<RunItemState> RunItems { get; set; } = new List<RunItemState>();

        internal RunNodeCompletionSnapshot Clone()
        {
            return new RunNodeCompletionSnapshot
            {
                InventorySnapshot = InventoryCloneUtility.CloneInventory(InventorySnapshot),
                ThemeType = ThemeType,
                ThemeStageIndex = ThemeStageIndex,
                CurrentThemePool = RunStateCloneUtility.CloneThemeList(CurrentThemePool),
                ThemeHistory = RunStateCloneUtility.CloneThemeList(ThemeHistory),
                CurrentNodeContinueChallengeLayer = CurrentNodeContinueChallengeLayer,
                RunItems = RunStateCloneUtility.CloneRunItems(RunItems)
            };
        }
    }

    [Serializable]
    public sealed class RunState
    {
        private readonly List<RunNodeState> _nodes;

        internal RunState(
            string runId,
            int runSeed,
            LevelThemeType themeType,
            List<RunNodeState> nodes,
            BackpackInventoryData runInventorySnapshot)
        {
            RunId = string.IsNullOrWhiteSpace(runId) ? Guid.NewGuid().ToString("N") : runId;
            RunSeed = runSeed == 0 ? RunStateFactory.CreateRunSeed() : runSeed;
            ThemeType = themeType;
            _nodes = nodes ?? new List<RunNodeState>();
            RunInventorySnapshot = InventoryCloneUtility.CloneInventory(runInventorySnapshot);
            ThemeStageIndex = 0;
            CurrentThemePool = CreateDefaultThemeList(themeType);
            ThemeHistory = CreateDefaultThemeList(themeType);
            CurrentNodeContinueChallengeLayer = 0;
            RunItems = new List<RunItemState>();
            CurrentNodeIndex = _nodes.Count > 0 ? 0 : -1;
            IsCompleted = _nodes.Count <= 0;
        }

        public string RunId { get; internal set; }

        public int RunSeed { get; internal set; }

        public LevelThemeType ThemeType { get; internal set; }

        public int CurrentNodeIndex { get; internal set; }

        public bool IsCompleted { get; internal set; }

        public BackpackInventoryData RunInventorySnapshot { get; internal set; }

        public int ThemeStageIndex { get; internal set; }

        public List<LevelThemeType> CurrentThemePool { get; internal set; }

        public List<LevelThemeType> ThemeHistory { get; internal set; }

        public int CurrentNodeContinueChallengeLayer { get; internal set; }

        public List<RunItemState> RunItems { get; internal set; }

        public IReadOnlyList<RunNodeState> Nodes => _nodes;

        public int NodeCount => _nodes.Count;

        public RunNodeState CurrentNode
        {
            get
            {
                if (CurrentNodeIndex < 0 || CurrentNodeIndex >= _nodes.Count)
                {
                    return null;
                }

                return _nodes[CurrentNodeIndex];
            }
        }

        public bool CanEnterCurrentNode => !IsCompleted && CurrentNode != null && CurrentNode.Status == RunNodeStatus.Available;

        public RunNodeState GetNodeBySequenceIndex(int sequenceIndex)
        {
            if (sequenceIndex < 0)
            {
                return null;
            }

            foreach (RunNodeState nodeState in _nodes)
            {
                if (nodeState.SequenceIndex == sequenceIndex)
                {
                    return nodeState;
                }
            }

            return null;
        }

        public static bool IsBossNode(RunNodeState nodeState)
        {
            return nodeState != null && nodeState.NodeType == RunNodeType.BossCombat;
        }

        public int CompletedNodeCount
        {
            get
            {
                int count = 0;
                foreach (var nodeState in _nodes)
                {
                    if (nodeState.Status == RunNodeStatus.Completed)
                    {
                        count++;
                    }
                }

                return count;
            }
        }

        internal void ReplaceInventorySnapshot(BackpackInventoryData inventorySnapshot)
        {
            RunInventorySnapshot = InventoryCloneUtility.CloneInventory(inventorySnapshot);
        }

        public RunNodeExecutionContext CreateCurrentNodeContext()
        {
            RunNodeState currentNode = CurrentNode;
            if (currentNode == null)
            {
                return null;
            }

            return new RunNodeExecutionContext
            {
                RunId = RunId,
                RunSeed = RunSeed,
                NodeId = currentNode.NodeId,
                NodeType = currentNode.NodeType,
                SequenceIndex = currentNode.SequenceIndex,
                ThemeType = ThemeType,
                ThemeStageIndex = ThemeStageIndex,
                CurrentThemePool = RunStateCloneUtility.CloneThemeList(CurrentThemePool),
                ThemeHistory = RunStateCloneUtility.CloneThemeList(ThemeHistory),
                CurrentNodeContinueChallengeLayer = CurrentNodeContinueChallengeLayer,
                RunItems = RunStateCloneUtility.CloneRunItems(RunItems)
            };
        }

        public void ApplyCompletionSnapshot(RunNodeCompletionSnapshot completionSnapshot)
        {
            RunInventorySnapshot = InventoryCloneUtility.CloneInventory(completionSnapshot.InventorySnapshot);
            ThemeType = completionSnapshot.ThemeType;
            ThemeStageIndex = completionSnapshot.ThemeStageIndex;
            CurrentThemePool = RunStateCloneUtility.CloneThemeList(completionSnapshot.CurrentThemePool);
            ThemeHistory = RunStateCloneUtility.CloneThemeList(completionSnapshot.ThemeHistory);
            CurrentNodeContinueChallengeLayer = completionSnapshot.CurrentNodeContinueChallengeLayer;
            RunItems = RunStateCloneUtility.CloneRunItems(completionSnapshot.RunItems);
        }

        private static List<LevelThemeType> CreateDefaultThemeList(LevelThemeType themeType)
        {
            List<LevelThemeType> themes = new List<LevelThemeType>();
            if (themeType != LevelThemeType.None)
            {
                themes.Add(themeType);
            }

            return themes;
        }
    }

    internal static class RunStateCloneUtility
    {
        internal static List<LevelThemeType> CloneThemeList(IReadOnlyList<LevelThemeType> source)
        {
            List<LevelThemeType> cloned = new List<LevelThemeType>();
            if (source == null)
            {
                return cloned;
            }

            for (int i = 0; i < source.Count; i++)
            {
                cloned.Add(source[i]);
            }

            return cloned;
        }

        internal static List<RunItemState> CloneRunItems(IReadOnlyList<RunItemState> source)
        {
            List<RunItemState> cloned = new List<RunItemState>();
            if (source == null)
            {
                return cloned;
            }

            for (int i = 0; i < source.Count; i++)
            {
                RunItemState item = source[i];
                if (item != null)
                {
                    cloned.Add(item.Clone());
                }
            }

            return cloned;
        }
    }
}