using Godot;

public partial class Player : Sprite2D
{
    // 1. Logical Grid Coordinates (0,0 is top left)
    private int _gridX = 0;
    private int _gridY = 0;

    // The default Godot icon is 128x128 pixels
    private int _tileSize = 128;

    // State machine flag to prevent input while sliding
    private bool _isMoving = false;

    public override void _Process(double delta)
    {
        // If we are currently animating a slide, ignore the keyboard
        if (_isMoving) return;

        Vector2 direction = Vector2.Zero;

        // Trigger only once per key press
        if (Input.IsActionJustPressed("ui_right")) direction.X = 1;
        else if (Input.IsActionJustPressed("ui_left")) direction.X = -1;
        else if (Input.IsActionJustPressed("ui_down")) direction.Y = 1;
        else if (Input.IsActionJustPressed("ui_up")) direction.Y = -1;

        if (direction != Vector2.Zero)
        {
            SlideTile((int)direction.X, (int)direction.Y);
        }
    }

    private void SlideTile(int dirX, int dirY)
    {
        int testGridX = _gridX;
        int testGridY = _gridY;

        // 1. The "Slide on Ice" Loop
        while (true)
        {
            int nextGridX = testGridX + dirX;
            int nextGridY = testGridY + dirY;

            // Check if the next step is outside the 5x4 boundary
            if (nextGridX < 0 || nextGridX >= 5 || nextGridY < 0 || nextGridY >= 4)
            {
                break; // Stop looking, we hit a wall!
            }

            // TODO: In the future, we will also check: 
            // if (_gridArray[nextGridX, nextGridY] != null) { break; }

            // If the space is valid, update our test coordinates and loop again
            testGridX = nextGridX;
            testGridY = nextGridY;
        }

        // 2. Did we actually move?
        if (testGridX == _gridX && testGridY == _gridY)
        {
            return; // We were already against a wall, do nothing
        }

        // 3. Update our logical position to the final destination
        _gridX = testGridX;
        _gridY = testGridY;

        Vector2 targetPixelPos = new Vector2(_gridX * _tileSize, _gridY * _tileSize);

        // 4. Calculate animation time based on distance traveled
        // So moving 4 tiles doesn't look 4x faster than moving 1 tile
        float distance = Mathf.Abs(dirX != 0 ? _gridX - testGridX : _gridY - testGridY) * _tileSize;
        // Use a base speed (e.g., 600 pixels per second)
        float tweenDuration = distance / 600.0f;

        // 5. Animate the slide
        _isMoving = true;
        Tween tween = CreateTween();

        tween.TweenProperty(this, "position", targetPixelPos, tweenDuration);
        tween.Finished += () => _isMoving = false;
    }
}