AceField-New-Horizon/Scripts/System/PlacementManager.cs

using System;
using AceFieldNewHorizon.Scripts.Tiles;
using Godot;

namespace AceFieldNewHorizon.Scripts.System;

public partial class PlacementManager : Node2D
{
    [Export] public GridManager Grid { get; set; }
    [Export] public BuildingRegistry Registry { get; set; }

    private string _currentBuildingId = "wall";
    private GridLayer _currentLayer = GridLayer.Building; // Default layer
    private Vector2I _hoveredCell;
    private BaseTile _ghostBuilding;
    private float _currentRotation = 0f;

    public void SetCurrentBuilding(string buildingId, GridLayer layer = GridLayer.Building)
    {
        _currentBuildingId = buildingId;
        _currentLayer = layer;

        // Replace ghost immediately
        if (_ghostBuilding == null) return;
        _ghostBuilding.QueueFree();
        _ghostBuilding = null;
    }

    public void SetCurrentLayer(GridLayer layer)
    {
        _currentLayer = layer;
        // Update ghost building if needed
        if (_ghostBuilding != null)
        {
            _ghostBuilding.QueueFree();
            _ghostBuilding = null;
        }
    }

    private void RotateGhost(bool reverse = false)
    {
        if (_ghostBuilding == null) return;
        if (reverse)
            _currentRotation = (_currentRotation - 90f) % 360f;
        else
            _currentRotation = (_currentRotation + 90f) % 360f;
        _ghostBuilding.RotationDegrees = _currentRotation;
    }

    public override void _Process(double delta)
    {
        // Snap mouse to grid
        var mousePos = GetGlobalMousePosition();
        _hoveredCell = GridUtils.WorldToGrid(mousePos);

        if (Input.IsActionJustPressed("rotate_tile_reverse"))
            RotateGhost(reverse: true);
        else if (Input.IsActionJustPressed("rotate_tile"))
            RotateGhost();

        if (_ghostBuilding == null)
        {
            var scene = Registry.GetBuilding(_currentBuildingId)?.Scene;
            if (scene == null) return;

            _ghostBuilding = (BaseTile)scene.Instantiate();
            _ghostBuilding.SetGhostMode(true);
            _ghostBuilding.RotationDegrees = _currentRotation;
            _ghostBuilding.ZAsRelative = false;
            _ghostBuilding.ZIndex = (int)_currentLayer; // Use layer as Z-index
            AddChild(_ghostBuilding);
        }

        var placementPos = GridUtils.GridToWorld(_hoveredCell);
        var spaceState = GetWorld2D().DirectSpaceState;
        var centerPos = placementPos + new Vector2(GridUtils.TileSize / 2f, GridUtils.TileSize / 2f);

        var query = new PhysicsPointQueryParameters2D
        {
            Position = centerPos,
            CollideWithBodies = true,
            CollideWithAreas = true,
            CollisionMask = uint.MaxValue
        };

        var collision = spaceState.IntersectPoint(query, 8);
        
        // Check if the current cell is free in the current layer
        var canPlace = Grid.IsCellFree(_hoveredCell, _currentLayer) && 
                      !Grid.IsAnyCellOccupied(_hoveredCell, GetBlockingLayers());

        _ghostBuilding.Position = placementPos;
        _ghostBuilding.SetGhostMode(canPlace);

        // Left click to place
        if (Input.IsActionPressed("build_tile") && canPlace)
        {
            var scene = Registry.GetBuilding(_currentBuildingId)?.Scene;
            if (scene == null) return;

            _ghostBuilding.FinalizePlacement();
            _ghostBuilding.RotationDegrees = _currentRotation;
            _ghostBuilding.ZIndex = (int)_currentLayer;

            var buildingData = Registry.GetBuilding(_currentBuildingId);
            Grid.OccupyCell(_hoveredCell, _ghostBuilding, _currentLayer);

            if (buildingData is { BuildTime: > 0f })
                _ghostBuilding.StartConstruction(buildingData.BuildTime);

            // Create new ghost for next placement
            _ghostBuilding = (BaseTile)scene.Instantiate();
            _ghostBuilding.SetGhostMode(true);
            _ghostBuilding.RotationDegrees = _currentRotation;
            _ghostBuilding.ZAsRelative = false;
            _ghostBuilding.ZIndex = (int)_currentLayer;
            AddChild(_ghostBuilding);
        }

        if (Input.IsActionPressed("destroy_tile") && !Grid.IsCellFree(_hoveredCell, _currentLayer))
        {
            // Right click to destroy from current layer
            var building = Grid.GetBuildingAtCell(_hoveredCell, _currentLayer);
            if (building == null) return;
            building.QueueFree();
            Grid.FreeCell(_hoveredCell, _currentLayer);
        }
    }

    // Define which layers should block placement
    private GridLayer[] GetBlockingLayers()
    {
        return _currentLayer switch
        {
            GridLayer.Ground => new[] { GridLayer.Ground },
            GridLayer.Building => new[] { GridLayer.Ground, GridLayer.Building },
            GridLayer.Decoration => new[] { GridLayer.Ground, GridLayer.Building, GridLayer.Decoration },
            _ => []
        };
    }
}