// Callback type definitions
type GetSizeCallback = (element: dia.Element) => dia.Size;
type GetLabelSizeCallback = (cell: dia.Link | dia.Element) => dia.Size | undefined;
type SetPositionCallback = (element: dia.Element, position: dia.Point) => void;
type SetVerticesCallback = (link: dia.Link, vertices: dia.Point[]) => void;
type SetLabelsCallback = (link: dia.Link, labelPosition: dia.Point, points: dia.Point[]) => void;
type SetAnchorCallback = (link: dia.Link, linkEndPoint: dia.Point, bbox: dia.BBox, endType: 'source' | 'target') => void;

interface Options {
    // Layout direction (default: LayerDirectionEnum.TB)
    layerDirection?: LayerDirectionEnum;
    
    // Spacing (defaults: layerSeparation: 40, nodeSeparation: 20)
    layerSeparation?: number;
    nodeSeparation?: number;
    
    // Edge routing (defaults: edgeRoutingMode: EdgeRoutingMode.Rectilinear, polylinePadding: 1)
    edgeRoutingMode?: EdgeRoutingMode;
    polylinePadding?: number;
    
    // Grid and margins (defaults: gridSize: 10, margins: {left: 10, right: 10, top: 10, bottom: 10})
    gridSize?: number;
    margins?: {
        left: number;
        right: number;
        top: number;
        bottom: number;
    };
    
    // Element sizing callbacks (defaults: element.size(), element.get('labelSize'))
    getSize?: GetSizeCallback;
    getLabelSize?: GetLabelSizeCallback;
    
    // Layout application callbacks (defaults: all true with built-in implementations)
    setPosition?: SetPositionCallback;
    setVertices?: boolean | SetVerticesCallback;
    setLabels?: boolean | SetLabelsCallback;
    setAnchor?: boolean | SetAnchorCallback;
}

// Enums
enum LayerDirectionEnum {
    TB, // Top to Bottom
    BT, // Bottom to Top  
    LR, // Left to Right
    RL  // Right to Left
}

enum EdgeRoutingMode {
    SplineBundling = 1, // Smooth curved edges
    Rectilinear = 4     // Orthogonal edges with right angles
}

function layout(graphOrCells: dia.Graph | dia.Cell[], options?: Options): g.Rect