feat: calculate layer

packages/utils/dag.js

@@ -0,0 +1,30 @@
+export default class DAG {
+  constructor(nodes) {
+    this.nodes = new Map(nodes.map((node) => [node._id, node]))
+    this.edges = []
+  }
+
+  setLayer(id) {
+    console.log(`setLayer(${id})`)
+    const node = this.nodes.get(id)
+    if (!node) {
+      throw new Error(`Node ${id} not found`)
+    }
+    if (node.layer !== undefined) {
+      return node.layer
+    }
+    const previousLayer = node.requirements.map((rId) => this.setLayer(rId))
+    node.layer = Math.max(...previousLayer, 0) + 1
+    return node.layer
+  }
+
+  format() {
+    this.nodes.forEach((_, id) => {
+      this.setLayer(id)
+    })
+  }
+
+  get(id) {
+    return this.nodes.get(id)
+  }
+}