Added env configuration for plugins

* Added env.

* Added tree config.

* Added tree.

* Fixed settings test.

* Added test cases.

src/node/utils/SettingsTree.ts

@@ -0,0 +1,112 @@
+import {MapArrayType} from "../types/MapType";
+
+export class SettingsTree {
+    private children: Map<string, SettingsNode>;
+    constructor() {
+        this.children = new Map();
+    }
+
+    public addChild(key: string, value: string) {
+        this.children.set(key, new SettingsNode(key, value));
+    }
+
+    public removeChild(key: string) {
+        this.children.delete(key);
+    }
+
+    public getChild(key: string) {
+        return this.children.get(key);
+    }
+
+    public hasChild(key: string) {
+        return this.children.has(key);
+    }
+}
+
+
+export class SettingsNode {
+    private readonly key: string;
+    private value:  string | number | boolean | null | undefined;
+    private children: MapArrayType<SettingsNode>;
+
+    constructor(key: string, value?:  string | number | boolean | null | undefined) {
+        this.key = key;
+        this.value = value;
+        this.children = {}
+    }
+
+    public addChild(path: string[], value: string) {
+        let currentNode:SettingsNode = this;
+        for (let i = 0; i < path.length; i++) {
+            const key = path[i];
+            /*
+                Skip the current node if the key is the same as the current node's key
+             */
+            if (key === this.key ) {
+                continue
+            }
+            /*
+                If the current node does not have a child with the key, create a new node with the key
+             */
+            if (!currentNode.hasChild(key)) {
+                currentNode = currentNode.children[key] = new SettingsNode(key, this.coerceValue(value));
+            } else {
+                /*
+                 Else move to the child node
+                 */
+                currentNode = currentNode.getChild(key);
+            }
+        }
+    }
+
+
+    public collectFromLeafsUpwards() {
+        let collected:MapArrayType<any> = {};
+        for (const key in this.children) {
+            const child = this.children[key];
+            if (child.hasChildren()) {
+                collected[key] = child.collectFromLeafsUpwards();
+            } else {
+                collected[key] = child.value;
+            }
+        }
+        return collected;
+    }
+
+    coerceValue = (stringValue: string) => {
+        // cooked from https://stackoverflow.com/questions/175739/built-in-way-in-javascript-to-check-if-a-string-is-a-valid-number
+        // @ts-ignore
+        const isNumeric = !isNaN(stringValue) && !isNaN(parseFloat(stringValue) && isFinite(stringValue));
+
+        if (isNumeric) {
+            // detected numeric string. Coerce to a number
+
+            return +stringValue;
+        }
+
+        switch (stringValue) {
+            case 'true':
+                return true;
+            case 'false':
+                return false;
+            case 'undefined':
+                return undefined;
+            case 'null':
+                return null;
+            default:
+                return stringValue;
+        }
+    };
+
+    public hasChildren() {
+        return Object.keys(this.children).length > 0;
+    }
+
+    public getChild(key: string) {
+        return this.children[key];
+    }
+
+    public hasChild(key: string) {
+        return this.children[key] !== undefined;
+    }
+}