fix(frontend): Fix loops pickable properties (#441)

frontend/src/lib/components/ModuleStep.svelte

@@ -23,6 +23,7 @@
 	import { flowStateStore, type FlowModuleSchema, type FlowState } from './flows/flowState'
 	import { stepOpened } from './flows/stepOpenedStore'
 	import { buildExtraLib, objectToTsType, schemaToObject, schemaToTsType } from '$lib/utils'
+	import { rotateRight } from 'svelte-awesome/icons'
 
 	export let indexes: number[]
 	export let mod: FlowModule
@@ -37,29 +38,50 @@
 	let pickableProperties: Object | undefined = undefined
 	let bigEditor = false
 
+	const i = indexes[0]
+
 	type PickableProperties = {
 		flow_input?: Object
 		previous_result?: Object
 		step?: Object[]
 	}
 
-	const i = indexes[0]
+	function hasElements(arr: any) {
+		return Array.isArray(arr) && arr.length > 0
+	}
 
-	function getPickableProperties(flow: Flow): PickableProperties {
+	function getLast<T>(arr: T[]): T {
+		return arr[arr.length - 1]
+	}
+
+	function getPickableProperties(flow: Flow, flowState: FlowState): PickableProperties {
 		const flowInputAsObject = schemaToObject(flow.schema, args)
 
 		if (indexes.length > 1) {
-			const prev = $flowStateStore[i - 1].previewResults
-			const prevValues = prev[prev.length - 1]
+			const [parentIndex] = indexes
+
+			const stepBeforeLoop = flowState[parentIndex - 1]
+
 			flowInputAsObject['iter'] = {
-				value: prevValues?.[prevValues.length - 1] ?? "iteration's value",
-				index: `iteration's index (0 to ${prevValues ? prevValues.length - 1 : '..'})`
+				value: "iteration's value",
+				index: "iteration's index"
+			}
+
+			if (hasElements(stepBeforeLoop.previewResults)) {
+				const lastResults = getLast(stepBeforeLoop.previewResults)
+
+				if (hasElements(lastResults)) {
+					flowInputAsObject['iter'] = {
+						value: getLast(lastResults),
+						index: `iteration's index (0 to ${lastResults.length - 1})`
+					}
+				}
 			}
 		}
 
-		const hasResults = previousStepPreviewResults.length > 0
+		const hasResults = hasElements(previousStepPreviewResults)
+		const last = hasResults ? getLast(previousStepPreviewResults) : {}
 
-		const last = hasResults ? previousStepPreviewResults[previousStepPreviewResults.length - 1] : {}
 		return {
 			flow_input: flowInputAsObject,
 			previous_result: last,
@@ -68,7 +90,7 @@
 	}
 
 	$: shouldPick = 'path' in mod.value && mod.value.path === '' && !('language' in mod.value)
-	$: pickableProperties = getPickableProperties($flowStore)
+	$: pickableProperties = getPickableProperties($flowStore, $flowStateStore)
 	$: extraLib = buildExtraLib(
 		schemaToTsType($flowStore?.schema),
 		i === 0 ? schemaToTsType($flowStore?.schema) : objectToTsType(previousStepPreviewResults)
@@ -140,8 +162,8 @@
 		{#if opened}
 			{#if shouldPick}
 				<FlowInputs
-					shouldDisableTriggerScripts={i != 0}
-					shouldDisableLoopCreation={indexes.length > 1 || i == 0}
+					shouldDisableTriggerScripts={indexes[0] > 0}
+					shouldDisableLoopCreation={indexes.length > 1 || indexes[0] == 0}
 					on:pick={(e) => apply(pickScript, e.detail.path)}
 					on:new={(e) =>
 						apply(createInlineScriptModule, {