1 files changed, 105 insertions, 0 deletions
diff --git a/alpinejs/packages/alpinejs/src/scope.js b/alpinejs/packages/alpinejs/src/scope.js
new file mode 100644
index 0000000..abceae6
--- /dev/null
+++ b/alpinejs/packages/alpinejs/src/scope.js
@@ -0,0 +1,105 @@
+
+export function scope(node) {
+    return mergeProxies(closestDataStack(node))
+}
+
+export function addScopeToNode(node, data, referenceNode) {
+    node._x_dataStack = [data, ...closestDataStack(referenceNode || node)]
+
+    return () => {
+        node._x_dataStack = node._x_dataStack.filter(i => i !== data)
+    }
+}
+
+export function hasScope(node) {
+    return !! node._x_dataStack
+}
+
+export function refreshScope(element, scope) {
+    let existingScope = element._x_dataStack[0]
+
+    Object.entries(scope).forEach(([key, value]) => {
+        existingScope[key] = value
+    })
+}
+
+export function closestDataStack(node) {
+    if (node._x_dataStack) return node._x_dataStack
+
+    if (typeof ShadowRoot === 'function' && node instanceof ShadowRoot) {
+        return closestDataStack(node.host)
+    }
+
+    if (! node.parentNode) {
+        return []
+    }
+
+    return closestDataStack(node.parentNode)
+}
+
+export function closestDataProxy(el) {
+    return mergeProxies(closestDataStack(el))
+}
+
+export function mergeProxies(objects) {
+    let thisProxy = new Proxy({}, {
+        ownKeys: () => {
+            return Array.from(new Set(objects.flatMap(i => Object.keys(i))))
+        },
+
+        has: (target, name) => {
+            return objects.some(obj => obj.hasOwnProperty(name))
+        },
+
+        get: (target, name) => {
+            return (objects.find(obj => {
+                if (obj.hasOwnProperty(name)) {
+                    let descriptor = Object.getOwnPropertyDescriptor(obj, name)
+
+                    // If we already bound this getter, don't rebind.
+                    if ((descriptor.get && descriptor.get._x_alreadyBound) || (descriptor.set && descriptor.set._x_alreadyBound)) {
+                        return true
+                    }
+                    
+                    // Properly bind getters and setters to this wrapper Proxy.
+                    if ((descriptor.get || descriptor.set) && descriptor.enumerable) {
+                        // Only bind user-defined getters, not our magic properties.
+                        let getter = descriptor.get
+                        let setter = descriptor.set
+                        let property = descriptor
+
+                        getter = getter && getter.bind(thisProxy)
+                        setter = setter && setter.bind(thisProxy)
+
+                        if (getter) getter._x_alreadyBound = true
+                        if (setter) setter._x_alreadyBound = true
+
+                        Object.defineProperty(obj, name, {
+                            ...property,
+                            get: getter,
+                            set: setter,
+                        })
+                    }
+
+                    return true 
+                }
+
+                return false
+            }) || {})[name]
+        },
+
+        set: (target, name, value) => {
+            let closestObjectWithKey = objects.find(obj => obj.hasOwnProperty(name))
+
+            if (closestObjectWithKey) {
+                closestObjectWithKey[name] = value
+            } else {
+                objects[objects.length - 1][name] = value
+            }
+
+            return true
+        },
+    })
+
+    return thisProxy
+}