From 395dcd1cc2a5e5d6b6a54b7fc4859fe6f4bb6356 Mon Sep 17 00:00:00 2001
From: Martin McKeaveney <martin@shogunsystems.co.uk>
Date: Fri, 21 Feb 2020 18:02:02 +0000
Subject: [PATCH] finished state management ui for v2

---
 packages/builder/src/common/Input.svelte      |   2 +-
 packages/builder/src/common/Select.svelte     |   4 +-
 .../EventsEditor/HandlerSelector.svelte       |  29 +-
 .../EventsEditor/StateBindingCascader.svelte  |  43 ++-
 .../PropertyCascader.svelte                   |  67 ++---
 .../StateBindingOptions.svelte                |  63 ++++
 .../userInterface/PropertyCascader/index.js   |   1 +
 .../userInterface/StateBindingControl.svelte  |   2 +-
 packages/client/src/state/parseBinding.js     |  19 +-
 packages/client/src/state/stateManager.js     |  63 ++--
 .../stateManager/dynamicPropertySource.js     |   0
 .../client/src/state/stateManager/index.js    | 274 ++++++++++++++++++
 12 files changed, 451 insertions(+), 116 deletions(-)
 rename packages/builder/src/userInterface/{ => PropertyCascader}/PropertyCascader.svelte (64%)
 create mode 100644 packages/builder/src/userInterface/PropertyCascader/StateBindingOptions.svelte
 create mode 100644 packages/builder/src/userInterface/PropertyCascader/index.js
 create mode 100644 packages/client/src/state/stateManager/dynamicPropertySource.js
 create mode 100644 packages/client/src/state/stateManager/index.js

diff --git a/packages/builder/src/common/Input.svelte b/packages/builder/src/common/Input.svelte
index e7c5e78841..50b07f41f0 100644
--- a/packages/builder/src/common/Input.svelte
+++ b/packages/builder/src/common/Input.svelte
@@ -22,6 +22,6 @@
     appearance: none;
     background: #fff;
     border: 1px solid #ccc;
-    height: 50px;
+    height: 35px;
   }
 </style>
diff --git a/packages/builder/src/common/Select.svelte b/packages/builder/src/common/Select.svelte
index be0ccafa7c..2b9b67bb85 100644
--- a/packages/builder/src/common/Select.svelte
+++ b/packages/builder/src/common/Select.svelte
@@ -23,11 +23,9 @@
 
   select {
     display: block;
-    font-size: 14px;
     font-family: sans-serif;
     font-weight: 500;
     color: #163057;
-    line-height: 1.3;
     padding: 1em 2.6em 0.9em 1.4em;
     width: 100%;
     max-width: 100%;
@@ -38,7 +36,7 @@
     appearance: none;
     background: #fff;
     border: 1px solid #ccc;
-    height: 50px;
+    height: 35px;
   }
 
   .arrow {
diff --git a/packages/builder/src/userInterface/EventsEditor/HandlerSelector.svelte b/packages/builder/src/userInterface/EventsEditor/HandlerSelector.svelte
index 6315736581..d34b7303ab 100644
--- a/packages/builder/src/userInterface/EventsEditor/HandlerSelector.svelte
+++ b/packages/builder/src/userInterface/EventsEditor/HandlerSelector.svelte
@@ -50,31 +50,8 @@
     const handlerParams = {}
     for (let param of params) {
       handlerParams[param.name] = param.value
-
-      if (param.value.startsWith("context")) {
-        const [_, contextKey] = param.value.split(".");
-
-        handlerParams[param.name] = {
-          "##bbstate": contextKey,
-          "##bbsource": "context",
-          "##bbstatefallback": "balls to that",
-        }
-        console.log("Param starts with context", param.value);
-      };
-
-      if (param.value.startsWith("event")) {
-        const [_, eventKey] = param.value.split(".");
-        handlerParams[param.name] = {
-          "##bbstate": eventKey,
-          "##bbsource": "event",
-          "##bbstatefallback": "balls to that",
-        }
-      };
-
     }
 
-    console.log(type, params, handlerParams);
-
     const updatedHandler = {
       [EVENT_TYPE_MEMBER_NAME]: type,
       parameters: handlerParams,
@@ -96,9 +73,9 @@
   }
 
   const onParameterChanged = index => e => {
-    const value = e.target.value
+    const value = e.target ? e.target.value : e
     const newParams = [...parameters]
-    newParams[index].value = e.target.value
+    newParams[index].value = value
     handlerChanged(handlerType, newParams)
   }
 </script>
@@ -116,7 +93,7 @@
     </div>
     {#if parameters}
       {#each parameters as parameter, idx}
-        <StateBindingCascader on:change={onParameterChanged(idx)} {parameter} />
+        <StateBindingCascader onChange={onParameterChanged(idx)} {parameter} />
       {/each}
     {/if}
   </div>
diff --git a/packages/builder/src/userInterface/EventsEditor/StateBindingCascader.svelte b/packages/builder/src/userInterface/EventsEditor/StateBindingCascader.svelte
index 37996fd373..15539f7b21 100644
--- a/packages/builder/src/userInterface/EventsEditor/StateBindingCascader.svelte
+++ b/packages/builder/src/userInterface/EventsEditor/StateBindingCascader.svelte
@@ -11,20 +11,61 @@
     allHandlers,
   } from "../../common/eventHandlers"
   import { store } from "../../builderStore"
+  import StateBindingOptions from "../PropertyCascader/StateBindingOptions.svelte"
+  import { ArrowDownIcon } from "../../common/Icons/"
 
   export let parameter
+  export let onChange
+
+  let isOpen = false
 </script>
 
 <div class="handler-option">
   <span>{parameter.name}</span>
-  <Input on:change value={parameter.value} />
+  <div class="handler-input">
+    <Input on:change={onChange} value={parameter.value} />
+    <button on:click={() => (isOpen = !isOpen)}>
+      <div class="icon" style={`transform: rotate(${isOpen ? 0 : 90}deg);`}>
+        <ArrowDownIcon size={36} />
+      </div>
+    </button>
+    {#if isOpen}
+      <StateBindingOptions
+        onSelect={option => {
+          onChange(option)
+          isOpen = false
+        }} />
+    {/if}
+  </div>
 </div>
 
 <style>
+  button {
+    cursor: pointer;
+    outline: none;
+    border: none;
+    border-radius: 5px;
+    background: rgba(249, 249, 249, 1);
+
+    font-size: 1.6rem;
+    font-weight: 700;
+    color: rgba(22, 48, 87, 1);
+    margin-left: 5px;
+  }
+
+  .icon {
+    width: 24px;
+  }
+
   .handler-option {
     display: flex;
     flex-direction: column;
   }
+  
+  .handler-input {
+    position: relative;
+    display: flex;
+  }
 
   span {
     font-size: 12px;
diff --git a/packages/builder/src/userInterface/PropertyCascader.svelte b/packages/builder/src/userInterface/PropertyCascader/PropertyCascader.svelte
similarity index 64%
rename from packages/builder/src/userInterface/PropertyCascader.svelte
rename to packages/builder/src/userInterface/PropertyCascader/PropertyCascader.svelte
index c1847aae33..f0b08d98d9 100644
--- a/packages/builder/src/userInterface/PropertyCascader.svelte
+++ b/packages/builder/src/userInterface/PropertyCascader/PropertyCascader.svelte
@@ -1,8 +1,9 @@
 <script>
-  import { ArrowDownIcon } from "../common/Icons/"
-  import { store } from "../builderStore"
-  import { buildStateOrigins } from "../builderStore/buildStateOrigins"
-  import { isBinding, getBinding, setBinding } from "../common/binding"
+  import { ArrowDownIcon } from "../../common/Icons/"
+  import { store } from "../../builderStore"
+  import { buildStateOrigins } from "../../builderStore/buildStateOrigins"
+  import { isBinding, getBinding, setBinding } from "../../common/binding"
+  import StateBindingOptions from "./StateBindingOptions.svelte";
 
   export let onChanged = () => {}
   export let value = ""
@@ -58,29 +59,20 @@
         setBindingFallback(e.target.value)
         onChanged(e.target.value)
       }} />
-    {#if stateBindings.length}
-      <button on:click={() => (isOpen = !isOpen)}>
-        <div
-          class="icon"
-          class:highlighted={bindingPath}
-          style={`transform: rotate(${isOpen ? 0 : 90}deg);`}>
-          <ArrowDownIcon size={36} />
-        </div>
-      </button>
-    {/if}
+    <button on:click={() => (isOpen = !isOpen)}>
+      <div
+        class="icon"
+        class:highlighted={bindingPath}
+        style={`transform: rotate(${isOpen ? 0 : 90}deg);`}>
+        <ArrowDownIcon size={36} />
+      </div>
+    </button>
   </div>
   {#if isOpen}
-    <ul class="options">
-      {#each stateBindings as stateBinding}
-        <li
-          class:bold={stateBinding === bindingPath}
-          on:click={() => {
-            setBindingPath(stateBinding === bindingPath ? null : stateBinding)
-          }}>
-          {stateBinding}
-        </li>
-      {/each}
-    </ul>
+    <StateBindingOptions onSelect={option => { 
+      onChanged(option);
+      isOpen = false;
+    }} />
   {/if}
 </div>
 
@@ -115,27 +107,6 @@
     align-items: center;
   }
 
-  .options {
-    width: 172px;
-    margin: 0;
-    position: absolute;
-    top: 35px;
-    padding: 10px;
-    z-index: 1;
-    background: rgba(249, 249, 249, 1);
-    min-height: 50px;
-    border-radius: 2px;
-  }
-
-  li {
-    list-style-type: none;
-  }
-
-  li:hover {
-    cursor: pointer;
-    font-weight: bold;
-  }
-
   input {
     margin-right: 5px;
     border: 1px solid #dbdbdb;
@@ -143,4 +114,8 @@
     opacity: 0.5;
     height: 40px;
   }
+
+  .icon {
+    width: 24px;
+  }
 </style>
diff --git a/packages/builder/src/userInterface/PropertyCascader/StateBindingOptions.svelte b/packages/builder/src/userInterface/PropertyCascader/StateBindingOptions.svelte
new file mode 100644
index 0000000000..bd35366929
--- /dev/null
+++ b/packages/builder/src/userInterface/PropertyCascader/StateBindingOptions.svelte
@@ -0,0 +1,63 @@
+<script>
+  export let onSelect = () => {}
+
+  let options = [
+    {
+      name: "state",
+      description: "Front-end client state.",
+    },
+    {
+      name: "context",
+      description: "The component context object.",
+    },
+    {
+      name: "event",
+      description: "DOM event handler arguments.",
+    },
+  ]
+</script>
+
+<ul class="options">
+  {#each options as option}
+    <li on:click={() => onSelect(`${option.name}.`)}>
+      <span class="name">{option.name}</span>
+      <span class="description">{option.description}</span>
+    </li>
+  {/each}
+</ul>
+
+<style>
+  .options {
+    width: 172px;
+    margin: 0;
+    position: absolute;
+    top: 35px;
+    padding: 10px;
+    z-index: 1;
+    background: rgba(249, 249, 249, 1);
+    min-height: 50px;
+    border-radius: 2px;
+  }
+
+  .description {
+    font-size: 0.8em;
+  }
+
+  .name {
+    color: rgba(22, 48, 87, 0.6);
+    font-size: 12px;
+    font-weight: bold;
+    text-transform: uppercase;
+    margin-top: 5px;
+    display: block;
+  }
+
+  .name:hover {
+    cursor: pointer;
+    font-weight: 800;
+  }
+
+  li {
+    list-style-type: none;
+  }
+</style>
diff --git a/packages/builder/src/userInterface/PropertyCascader/index.js b/packages/builder/src/userInterface/PropertyCascader/index.js
new file mode 100644
index 0000000000..14b79c4e0c
--- /dev/null
+++ b/packages/builder/src/userInterface/PropertyCascader/index.js
@@ -0,0 +1 @@
+export { default } from "./PropertyCascader.svelte"
\ No newline at end of file
diff --git a/packages/builder/src/userInterface/StateBindingControl.svelte b/packages/builder/src/userInterface/StateBindingControl.svelte
index 6a5237051b..f96ae7fd08 100644
--- a/packages/builder/src/userInterface/StateBindingControl.svelte
+++ b/packages/builder/src/userInterface/StateBindingControl.svelte
@@ -1,7 +1,7 @@
 <script>
   import IconButton from "../common/IconButton.svelte"
   import Input from "../common/Input.svelte"
-  import PropertyCascader from "./PropertyCascader.svelte"
+  import PropertyCascader from "./PropertyCascader"
   import { isBinding, getBinding, setBinding } from "../common/binding"
 
   export let value = ""
diff --git a/packages/client/src/state/parseBinding.js b/packages/client/src/state/parseBinding.js
index 532e87aae2..c91fced285 100644
--- a/packages/client/src/state/parseBinding.js
+++ b/packages/client/src/state/parseBinding.js
@@ -4,8 +4,14 @@ export const BB_STATE_FALLBACK = "##bbstatefallback"
 
 export const isBound = prop => !!parseBinding(prop)
 
+/**
+ * 
+ * @param {object|string|number} prop - component property to parse for a dynamic state binding
+ * @returns {object|boolean}  
+ */
 export const parseBinding = prop => {
   if (!prop) return false
+
   if (isBindingExpression(prop)) {
     return parseBindingExpression(prop)
   }
@@ -38,21 +44,22 @@ const isAlreadyBinding = prop => typeof prop === "object" && prop.path
 
 const isBindingExpression = prop =>
   typeof prop === "string" &&
-  (prop.startsWith("store.") ||
+  (prop.startsWith("state.") ||
     prop.startsWith("context.") ||
     prop.startsWith("event.") ||
     prop.startsWith("route."))
 
 const parseBindingExpression = prop => {
-  let source = prop.split(".")[0]
-  let path = prop.replace(`${source}.`, "")
+  let [source, ...rest] = prop.split(".");
+  let path = rest.join(".") 
+
   if (source === "route") {
-    source = "store"
+    source = "state"
     path = `##routeParams.${path}`
   }
-  const fallback = ""
+
   return {
-    fallback,
+    fallback: "", // TODO: provide fallback support 
     source,
     path,
   }
diff --git a/packages/client/src/state/stateManager.js b/packages/client/src/state/stateManager.js
index 520b1767d3..3b625157f5 100644
--- a/packages/client/src/state/stateManager.js
+++ b/packages/client/src/state/stateManager.js
@@ -171,13 +171,14 @@ const _setup = (
   for (let propName in props) {
     if (isMetaProp(propName)) continue
 
-    const val = props[propName]
+    const propValue = props[propName]
 
-    const binding = parseBinding(val)
+    const binding = parseBinding(propValue)
     const isBound = !!binding
+
     if (isBound) binding.propName = propName
 
-    if (isBound && binding.source === "store") {
+    if (isBound && binding.source === "state") {
       storeBoundProps.push(binding)
 
       initialProps[propName] = !currentStoreState
@@ -188,16 +189,20 @@ const _setup = (
             binding.fallback,
             binding.source
           )
-    } else if (isBound && binding.source === "context") {
+    } 
+    
+    if (isBound && binding.source === "context") {
       initialProps[propName] = !context
-        ? val
+        ? propValue
         : getState(context, binding.path, binding.fallback, binding.source)
-    } else if (isEventType(val)) {
+    } 
+    
+    if (isEventType(propValue)) {
       const handlersInfos = []
-      for (let e of val) {
+      for (let event of propValue) {
         const handlerInfo = {
-          handlerType: e[EVENT_TYPE_MEMBER_NAME],
-          parameters: e.parameters,
+          handlerType: event[EVENT_TYPE_MEMBER_NAME],
+          parameters: event.parameters,
         }
         const resolvedParams = {}
         for (let paramName in handlerInfo.parameters) {
@@ -206,26 +211,20 @@ const _setup = (
           if (!paramBinding) {
             resolvedParams[paramName] = () => paramValue
             continue
-          } else if (paramBinding.source === "context") {
-            const val = getState(
-              context,
-              paramBinding.path,
-              paramBinding.fallback
-            )
-            resolvedParams[paramName] = () => val
-          } else if (paramBinding.source === "store") {
-            resolvedParams[paramName] = () =>
-              getState(
-                getCurrentState(),
-                paramBinding.path,
-                paramBinding.fallback
-              )
-            continue
-          } else if (paramBinding.source === "event") {
-            resolvedParams[paramName] = eventContext => {
-              getState(eventContext, paramBinding.path, paramBinding.fallback)
-            }
-          }
+          } 
+
+          let paramValueSource;
+
+          if (paramBinding.source === "context") paramValueSource = context;
+          if (paramBinding.source === "state") paramValueSource = getCurrentState();
+          if (paramBinding.source === "context") paramValueSource = context;
+
+          // The new dynamic event parameter bound to the relevant source
+          resolvedParams[paramName] = () => getState(
+            paramValueSource,
+            paramBinding.path,
+            paramBinding.fallback
+          );
         }
 
         handlerInfo.parameters = resolvedParams
@@ -256,9 +255,9 @@ const makeHandler = (handlerTypes, handlerInfo) => {
   const handlerType = handlerTypes[handlerInfo.handlerType]
   return context => {
     const parameters = {}
-    for (let p in handlerInfo.parameters) {
-      parameters[p] = handlerInfo.parameters[p](context)
+    for (let paramName in handlerInfo.parameters) {
+      parameters[paramName] = handlerInfo.parameters[paramName](context)
     }
     handlerType.execute(parameters)
   }
-}
+}
\ No newline at end of file
diff --git a/packages/client/src/state/stateManager/dynamicPropertySource.js b/packages/client/src/state/stateManager/dynamicPropertySource.js
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/packages/client/src/state/stateManager/index.js b/packages/client/src/state/stateManager/index.js
new file mode 100644
index 0000000000..09c80384c6
--- /dev/null
+++ b/packages/client/src/state/stateManager/index.js
@@ -0,0 +1,274 @@
+import {
+  isEventType,
+  eventHandlers,
+  EVENT_TYPE_MEMBER_NAME,
+} from "./eventHandlers"
+import { bbFactory } from "./bbComponentApi"
+import { getState } from "./getState"
+import { attachChildren } from "../render/attachChildren"
+
+import { parseBinding } from "./parseBinding"
+
+const doNothing = () => {}
+doNothing.isPlaceholder = true
+
+const isMetaProp = propName =>
+  propName === "_component" ||
+  propName === "_children" ||
+  propName === "_id" ||
+  propName === "_style" ||
+  propName === "_code" ||
+  propName === "_codeMeta"
+
+export const createStateManager = ({
+  store,
+  coreApi,
+  rootPath,
+  frontendDefinition,
+  componentLibraries,
+  uiFunctions,
+  onScreenSlotRendered,
+  routeTo,
+}) => {
+  let handlerTypes = eventHandlers(store, coreApi, rootPath, routeTo)
+  let currentState
+
+  // any nodes that have props that are bound to the store
+  let nodesBoundByProps = []
+
+  // any node whose children depend on code, that uses the store
+  let nodesWithCodeBoundChildren = []
+
+  const getCurrentState = () => currentState
+  const registerBindings = _registerBindings(
+    nodesBoundByProps,
+    nodesWithCodeBoundChildren
+  )
+  const bb = bbFactory({
+    store,
+    getCurrentState,
+    frontendDefinition,
+    componentLibraries,
+    uiFunctions,
+    onScreenSlotRendered,
+  })
+
+  const setup = _setup(handlerTypes, getCurrentState, registerBindings, bb)
+
+  const unsubscribe = store.subscribe(
+    onStoreStateUpdated({
+      setCurrentState: s => (currentState = s),
+      getCurrentState,
+      nodesWithCodeBoundChildren,
+      nodesBoundByProps,
+      uiFunctions,
+      componentLibraries,
+      onScreenSlotRendered,
+      setupState: setup,
+    })
+  )
+
+  return {
+    setup,
+    destroy: () => unsubscribe(),
+    getCurrentState,
+    store,
+  }
+}
+
+const onStoreStateUpdated = ({
+  setCurrentState,
+  getCurrentState,
+  nodesWithCodeBoundChildren,
+  nodesBoundByProps,
+  uiFunctions,
+  componentLibraries,
+  onScreenSlotRendered,
+  setupState,
+}) => s => {
+  setCurrentState(s)
+
+  // the original array gets changed by components' destroy()
+  // so we make a clone and check if they are still in the original
+  const nodesWithBoundChildren_clone = [...nodesWithCodeBoundChildren]
+  for (let node of nodesWithBoundChildren_clone) {
+    if (!nodesWithCodeBoundChildren.includes(node)) continue
+    attachChildren({
+      uiFunctions,
+      componentLibraries,
+      treeNode: node,
+      onScreenSlotRendered,
+      setupState,
+      getCurrentState,
+    })(node.rootElement, { hydrate: true, force: true })
+  }
+
+  for (let node of nodesBoundByProps) {
+    setNodeState(s, node)
+  }
+}
+
+const _registerBindings = (nodesBoundByProps, nodesWithCodeBoundChildren) => (
+  node,
+  bindings
+) => {
+  if (bindings.length > 0) {
+    node.bindings = bindings
+    nodesBoundByProps.push(node)
+    const onDestroy = () => {
+      nodesBoundByProps = nodesBoundByProps.filter(n => n === node)
+      node.onDestroy = node.onDestroy.filter(d => d === onDestroy)
+    }
+    node.onDestroy.push(onDestroy)
+  }
+  if (
+    node.props._children &&
+    node.props._children.filter(c => c._codeMeta && c._codeMeta.dependsOnStore)
+      .length > 0
+  ) {
+    nodesWithCodeBoundChildren.push(node)
+    const onDestroy = () => {
+      nodesWithCodeBoundChildren = nodesWithCodeBoundChildren.filter(
+        n => n === node
+      )
+      node.onDestroy = node.onDestroy.filter(d => d === onDestroy)
+    }
+    node.onDestroy.push(onDestroy)
+  }
+}
+
+const setNodeState = (storeState, node) => {
+  if (!node.component) return
+  const newProps = { ...node.bindings.initialProps }
+
+  for (let binding of node.bindings) {
+    const val = getState(storeState, binding.path, binding.fallback)
+
+    if (val === undefined && newProps[binding.propName] !== undefined) {
+      delete newProps[binding.propName]
+    }
+
+    if (val !== undefined) {
+      newProps[binding.propName] = val
+    }
+  }
+
+  node.component.$set(newProps)
+}
+
+/**
+ * Bind a components event handler parameters to state, context or the event itself.
+ * @param {Array} eventHandlerProp - event handler array from component definition
+ */
+function bindComponentEventHandlers(eventHandlerProp) {
+    const boundEventHandlers = []
+    for (let event of eventHandlerProp) {
+      const boundEventHandler = {
+        handlerType: event[EVENT_TYPE_MEMBER_NAME],
+        parameters: event.parameters,
+      }
+
+      const boundParameters = {}
+      for (let paramName in boundEventHandler.parameters) {
+        const paramValue = boundEventHandler.parameters[paramName]
+        const paramBinding = parseBinding(paramValue)
+        if (!paramBinding) {
+          boundParameters[paramName] = () => paramValue
+          continue
+        } 
+
+        let paramValueSource;
+
+        if (paramBinding.source === "context") paramValueSource = context;
+        if (paramBinding.source === "state") paramValueSource = getCurrentState();
+
+        // The new dynamic event parameter bound to the relevant source
+        boundParameters[paramName] = eventContext => getState(
+          paramBinding.source === "event" ? eventContext : paramValueSource,
+          paramBinding.path,
+          paramBinding.fallback
+        );
+      }
+
+      boundEventHandler.parameters = boundParameters
+      boundEventHandlers.push(boundEventHandlers)
+
+      return boundEventHandlers;
+    }
+}
+
+const _setup = (
+  handlerTypes,
+  getCurrentState,
+  registerBindings,
+  bb
+) => node => {
+  const props = node.props
+  const context = node.context || {}
+  const initialProps = { ...props }
+  const storeBoundProps = []
+  const currentStoreState = getCurrentState()
+
+  for (let propName in props) {
+    if (isMetaProp(propName)) continue
+
+    const propValue = props[propName]
+
+    const binding = parseBinding(propValue)
+    const isBound = !!binding
+
+    if (isBound) binding.propName = propName
+
+    if (isBound && binding.source === "state") {
+      storeBoundProps.push(binding)
+
+      initialProps[propName] = !currentStoreState
+        ? binding.fallback
+        : getState(
+            currentStoreState,
+            binding.path,
+            binding.fallback,
+            binding.source
+          )
+    } 
+    
+    if (isBound && binding.source === "context") {
+      initialProps[propName] = !context
+        ? propValue
+        : getState(context, binding.path, binding.fallback, binding.source)
+    } 
+    
+    if (isEventType(propValue)) { 
+      const boundEventHandlers = bindComponentEventHandlers(propValue); 
+
+      if (boundEventHandlers.length === 0) { 
+        initialProps[propName] = doNothing
+      } else {
+        initialProps[propName] = async context => {
+          for (let handlerInfo of handlersInfos) {
+            const handler = makeHandler(handlerTypes, handlerInfo)
+            await handler(context)
+          }
+        }
+      }
+    }
+  }
+
+  registerBindings(node, storeBoundProps)
+
+  const setup = _setup(handlerTypes, getCurrentState, registerBindings, bb)
+  initialProps._bb = bb(node, setup)
+
+  return initialProps
+}
+
+const makeHandler = (handlerTypes, handlerInfo) => {
+  const handlerType = handlerTypes[handlerInfo.handlerType]
+  return context => {
+    const parameters = {}
+    for (let paramName in handlerInfo.parameters) {
+      parameters[paramName] = handlerInfo.parameters[paramName](context)
+    }
+    handlerType.execute(parameters)
+  }
+}
\ No newline at end of file