1  // Function to parse DreamSong.canvas data
 2  export function parseDreamSongCanvas(canvasData) {
 3    if (typeof canvasData !== 'object' || canvasData === null) {
 4      return { nodes: [], edges: [] };
 5    }
 6    return {
 7      nodes: canvasData.nodes || [],
 8      edges: canvasData.edges || []
 9    };
10  }
11  
12  // Function to perform topological sorting of nodes
13  export function topologicalSort(nodes, edges) {
14    const graph = new Map();
15    const inDegree = new Map();
16  
17    // Initialize graph and in-degree
18    nodes.forEach(node => {
19      graph.set(node.id, []);
20      inDegree.set(node.id, 0);
21    });
22  
23    // Build graph and calculate in-degree
24    edges.forEach(edge => {
25      if (graph.has(edge.fromNode) && graph.has(edge.toNode)) {
26        graph.get(edge.fromNode).push(edge.toNode);
27        inDegree.set(edge.toNode, inDegree.get(edge.toNode) + 1);
28      }
29    });
30  
31    // Queue for nodes with no incoming edges
32    const queue = nodes.filter(node => inDegree.get(node.id) === 0).map(node => node.id);
33    const sortedNodes = [];
34  
35    while (queue.length > 0) {
36      const nodeId = queue.shift();
37      sortedNodes.push(nodes.find(node => node.id === nodeId));
38  
39      graph.get(nodeId).forEach(neighbor => {
40        inDegree.set(neighbor, inDegree.get(neighbor) - 1);
41        if (inDegree.get(neighbor) === 0) {
42          queue.push(neighbor);
43        }
44      });
45    }
46  
47    // Check for cycles
48    if (sortedNodes.length !== nodes.length) {
49      // Graph contains a cycle, but we'll return what we have
50    }
51  
52    return sortedNodes;
53  }
54  
55  // Function to process DreamSong data
56  export function processDreamSongData(canvasData) {
57    const { nodes, edges } = parseDreamSongCanvas(canvasData);
58    const sortedNodes = topologicalSort(nodes, edges);
59    return sortedNodes;
60  }