samples/graphChange.html

<!DOCTYPE html>
<html>
  <head>
    <script src="https://unpkg.com/chart.js@3.8.0/dist/chart.js"></script>
    <script src="../build/index.umd.js"></script>
  </head>

  <body>
    <div style="width: 75%">
      <canvas id="canvas"></canvas>
    </div>
    <button id="addNode">Add Node</button>
    <button id="removeNode">Remove Node</button>
    <button id="reset">Reset</button>
    <button id="relayout">Relayout</button>
    <script>
      fetch('./miserables.json')
        .then((r) => r.json())
        .then((data) => {
          const outgoingMap = new Map();
          data.nodes.forEach((n) => {
            const outgoing = data.links.filter((e) => e.source === n.id);
            outgoingMap.set(n.id, outgoing);
          });
          const sub = 3;
          const nodes = data.nodes.slice(0, data.nodes.length - sub);
          const rest = data.nodes.slice(data.nodes.length - sub);

          const labels = nodes.map((d) => d.id);
          const edges = nodes
            .reduce((acc, n) => acc.concat(outgoingMap.get(n.id)), [])
            .filter((d) => labels.indexOf(d.target) >= 0);

          const chart = new Chart(document.getElementById('canvas').getContext('2d'), {
            type: 'forceDirectedGraph',
            data: {
              labels,
              datasets: [
                {
                  pointBackgroundColor: 'steelblue',
                  pointRadius: 5,
                  data: nodes,
                  edges,
                },
              ],
            },
            options: {
              legend: {
                display: false,
              },
            },
          });
          const add = document.getElementById('addNode');
          const remove = document.getElementById('removeNode');
          add.onclick = () => {
            if (rest.length === 0) {
              return;
            }
            const node = rest.pop();
            const toAdd = outgoingMap
              .get(node.id)
              .filter((d) => labels.indexOf(d.target) >= 0 || nodes.indexOf(d.target) >= 0);
            nodes.forEach((n) => {
              outgoingMap.get(n.id).forEach((e) => {
                if (e.target === node.id || e.target === node) {
                  toAdd.push(e);
                }
              });
            });
            nodes.push(node);
            labels.push(node.id);
            edges.push(...toAdd);

            // console.log('add', node.name, toAdd.length, edges.length);
            add.disabled = rest.length === 0;
            remove.disabled = false;

            // console.log(nodes.map((d) => d.name), edges.map((d) => `${d.source.name || d.source}-${d.target.name || d.target}`));
          };
          remove.onclick = () => {
            if (nodes.length === 0) {
              return;
            }
            const index = Math.min(Math.floor(Math.random() * nodes.length), nodes.length - 1);
            const node = nodes.splice(index, 1)[0];
            delete node.x;
            delete node.y;
            delete node.vx;
            delete node.vy;

            labels.splice(index, 1);

            const toRemove = [];
            edges.forEach((e, i) => {
              if (e.source === node.id || e.target === node.id) {
                toRemove.push(i);
              }
            });
            toRemove.reverse().forEach((i) => {
              edges.splice(i, 1);
            });
            // console.log('remove', node.name, toRemove.length, edges.length);
            rest.push(node);

            add.disabled = false;
            remove.disabled = nodes.length === 0;
          };
          document.getElementById('reset').onclick = () => {
            chart.reset();
          };
          document.getElementById('relayout').onclick = () => {
            chart.getDatasetMeta(0).controller.reLayout();
          };
        });
    </script>
  </body>
</html>