using System;
using System.Collections.Generic;
using System.Linq;
using Cirno.Scripts.Enums;
using Cirno.Scripts.Resources.Roguelite;
using Cirno.Scripts.Utils;
using Godot;
using Godot.Collections;

namespace Cirno.Scripts.Controllers;

public partial class RogueliteRoomManager : Node2D
{
    [Export] public Array<RogueliteRoomResource> Rooms { get; set; }

    [Export] public Node2D SceneContainer { get; set; }

    //private Godot.Collections.Dictionary<Vector2I, RogueliteRoomResource> _grid = new();
    private Godot.Collections.Dictionary<Vector2I, RogueliteRoom> _roomGrid = new();

    public Godot.Collections.Dictionary<Vector2I, RogueliteRoom> RoomGrid => _roomGrid;

    public List<RogueliteRoom> SpawnedRooms { get; private set; } = [];

    [Export] public Vector2I SpawnOrigin { get; private set; } = Vector2I.Zero;

    [Export] public int DungeonLength { get; set; } = 10;
    [Export] public int MaxBranches { get; set; } = 3;
    [Export] public int MaxBranchLength { get; set; } = 3;

    [Export] public int DungeonWidth = 10;
    [Export] public int DungeonHeight = 10;
    [Export] public int MaxRooms = 12;
    [Export] public ulong Seed = 0;

    [Export] public Vector2I TileSize { get; set; } = new Vector2I(16, 16);
    [Export] public Vector2I RoomSizeInTiles { get; set; } = new Vector2I(20, 10);

    [Signal]
    public delegate void MapCreatedEventHandler();

    public override void _Ready()
    {
        // Spawn first room
    }

    public void InitSpawning()
    {
        GenerateStraightLineDungeon();
    }

    private void SpawnRoomsGrid()
    {
        //var firstRoom = Rooms.FirstOrDefault();

        var origin = Vector2.Zero;
        var tileSize = new Vector2(16, 16);

        for (int i = 0; i < 10; i++)
        {
            for (int j = 0; j < 10; j++)
            {
                var roomIndex = GD.RandRange(0, Rooms.Count - 1);
                var room = Rooms[roomIndex];
                //SpawnRoom(room, origin + (room.Size * new Vector2(i, j) * tileSize));
            }
        }

        //CallDeferred(MethodName.RebakeNavigationDeferred);
    }

    private IEnumerable<RogueliteRoomResource> StarterRooms => Rooms.Where(x => x.Type is RoomType.Starter);
    private IEnumerable<RogueliteRoomResource> RegularRooms => Rooms.Where(x => x.Type is RoomType.Regular);
    private IEnumerable<RogueliteRoomResource> BossRooms => Rooms.Where(x => x.Type is RoomType.Boss);

    private List<Vector2I> _mainPath = new();
    private List<RoomConnection> _connections = new();

    public List<RoomConnection> Connections => _connections;

    private void GenerateStraightLineDungeon()
    {
        if (Seed > 0)
        {
            GD.Seed(Seed);
        }

        Vector2I origin = Vector2I.Zero;
        var starterRoom = Rooms.Where(r => r.Type == RoomType.Starter).PickRandom();
        SpawnRoom(starterRoom, origin, out var spawnedBeginRoom);
        _mainPath.Add(origin);

        var randomRoomsList = RegularRooms.Shuffle(DungeonLength).ToList();

        var currentPos = origin;
        _connections.Add(new RoomConnection(origin, currentPos + new Vector2I(0, 1)));
        Vector2I nextPos;

        for (int i = 0; i < DungeonLength; i++)
        {
            nextPos = currentPos + new Vector2I(0, 1);

            //var roomToSpawn = Rooms.Where(x => x.Type == RoomType.Regular).PickRandom();
            var roomToSpawn = randomRoomsList[i];

            // First pick a random door on the from room
            //var doorOffset = Math.Min(0, GD.RandRange(0, currentRoom.Size.X - 1)); 

            // We're already in the new room position, we do not care about previous anymore

            var offset = 0;

            // Place it at a random X position
            if (roomToSpawn.Size.X > 1)
            {
                offset -= GD.RandRange(0, roomToSpawn.Size.X - 1);
            }

            nextPos += new Vector2I(offset, 0);

            //var posWithOffset = nextPos + new Vector2I(offset, 0);

            if (!SpawnRoom(roomToSpawn, nextPos, out var spawnedRoom))
            {
                GD.PrintErr("Could not spawn room");
                break;
            }

            _mainPath.Add(nextPos);

            // Place cursor at bottom of room
            if (roomToSpawn.Size.Y > 1)
            {
                nextPos += new Vector2I(0, roomToSpawn.Size.Y - 1);
            }

            // Pick a random exit to continue
            var exit = GD.RandRange(0, roomToSpawn.Size.X - 1);
            if (exit < 0) exit = 0;

            nextPos += new Vector2I(exit, 0);
            // nextPos is now the end of the room at the current exit

            _connections.Add(new RoomConnection(nextPos, nextPos + new Vector2I(0, 1)));
            //+ new Vector2I(0, roomToSpawn.Size.Y -1)
            // Reset X offset
            //nextPos = new Vector2I(0, nextPos.Y);

            currentPos = nextPos;
        }

        nextPos = currentPos + new Vector2I(0, 1);

        var bossRoom = BossRooms.PickRandom();

        if (SpawnRoom(bossRoom, nextPos, out var spawnedBossRoom))
        {
            _mainPath.Add(nextPos);

            if (bossRoom.Size.Y > 1)
            {
                nextPos += new Vector2I(0, bossRoom.Size.Y - 1);
            }

            _connections.Add(new RoomConnection(currentPos, nextPos));
        }
        else
        {
            GD.PrintErr("Could not spawn boss room");
        }

        foreach (var room in SpawnedRooms)
        {
            room.HandleDoors((doorEdge, pos) =>
            {
                //var neighborPos = room.GridPosition + pos;
                return _connections.FirstOrDefault(x =>
                    (x.From == doorEdge && x.To == pos) || (x.From == pos && x.To == doorEdge));
                //return _roomGrid.ContainsKey(neighborPos);
            });
        }

        EmitSignalMapCreated();
        
        //CallDeferred(MethodName.OpenStartDoorsDeferred, spawnedBeginRoom);
    }

    private Vector2I GetNextPosition(Vector2I current, Vector2I target)
    {
        var possibleDirs = new List<Vector2I>();

        if (target.X > current.X)
            possibleDirs.Add(Vector2I.Right);
        else if (target.X < current.X)
            possibleDirs.Add(Vector2I.Left);

        if (target.Y > current.Y)
            possibleDirs.Add(Vector2I.Down);
        else if (target.Y < current.Y)
            possibleDirs.Add(Vector2I.Up);

        // Add random noise to allow slightly winding paths
        possibleDirs.AddRange(new[] { Vector2I.Right, Vector2I.Left, Vector2I.Up, Vector2I.Down });

        possibleDirs = possibleDirs.Distinct().OrderBy(_ => GD.Randi()).ToList();

        foreach (var dir in possibleDirs)
        {
            var nextPos = current + dir;
            if (!_roomGrid.ContainsKey(nextPos))
                return nextPos;
        }

        return current; // No valid next position found
    }

    private void RebakeNavigationDeferred()
    {
        GameManager.Instance.RebakeNavigation();
    }

    private bool SpawnRoom(RogueliteRoomResource room, Vector2I gridPos, out RogueliteRoom spawnedRoom)
    {
        if (!CanPlaceRoom(gridPos, room.Size))
        {
            spawnedRoom = null;
            return false;
        }

        var position = gridPos * TileSize * RoomSizeInTiles;

        var roomScene = GD.Load<PackedScene>(room.ScenePath);
        var spawnedScene = this.CreateChild<RogueliteRoom>(roomScene, position);

        spawnedScene.GridPosition = gridPos;

        spawnedScene.Name = room.RoomName;
        
        SpawnedRooms.Add(spawnedScene);

        // for reference
        //SpawnRoom(room, origin + (room.Size * new Vector2(i, j) * tileSize));
        spawnedScene.Spawn();
        MarkRoom(gridPos, room.Size, spawnedScene);
        spawnedRoom = spawnedScene;
        return true;
    }

    // private bool CheckConnection(Vector2I pos)
    // {
    //     return _grid.ContainsKey(pos); // <- this is your dungeon grid dictionary
    // }
    //
    private bool CanPlaceRoom(Vector2I origin, Vector2I size)
    {
        for (int x = 0; x < size.X; x++)
        {
            for (int y = 0; y < size.Y; y++)
            {
                var pos = origin + new Vector2I(x, y);
                if (_roomGrid.ContainsKey(pos)) return false;
            }
        }

        return true;
    }

    private void MarkRoom(Vector2I origin, Vector2I size, RogueliteRoom room)
    {
        for (int x = 0; x < size.X; x++)
        {
            for (int y = 0; y < size.Y; y++)
            {
                var pos = origin + new Vector2I(x, y);
                _roomGrid[pos] = room;
            }
        }
    }
}