fix(ranking): restore local state, clear form sync and submit validation

Signed-off-by: paul bochtler <65470117+datapumpernickel@users.noreply.github.com>

Author: datapumpernickel

src/components/Questions/QuestionRanking.vue

@@ -10,6 +10,7 @@
 		:warningInvalid="answerType.warningInvalid"
 		:contentValid="contentValid"
 		:shiftDragHandle="shiftDragHandle"
+		:errorMessage="errorMessage"
 		v-on="commonListeners">
 		<template #actions>
 			<NcActionCheckbox
@@ -172,6 +173,7 @@
 </template>
 
 <script>
+import { translate as t } from '@nextcloud/l10n'
 import { VueDraggable as Draggable } from 'vue-draggable-plus'
 import NcActionButton from '@nextcloud/vue/components/NcActionButton'
 import NcActionCheckbox from '@nextcloud/vue/components/NcActionCheckbox'
@@ -215,6 +217,7 @@ export default {
 
 	data() {
 		return {
+			errorMessage: null,
 			isDragging: false,
 			isLoading: false,
 			isOptionDialogShown: false,
@@ -251,9 +254,39 @@ export default {
 				this.initRankedOptions()
 			},
 		},
+
+		values: {
+			immediate: true,
+			handler() {
+				this.initRankedOptions()
+			},
+		},
 	},
 
 	methods: {
+		async validate() {
+			const optionsCount = this.sortOptionsOfType(
+				this.options,
+				OptionType.Choice,
+			).length
+
+			if (this.isRequired && this.rankedOptions.length === 0) {
+				this.errorMessage = t('forms', 'You must choose at least one option')
+				return false
+			}
+
+			if (
+				this.rankedOptions.length > 0
+				&& this.rankedOptions.length !== optionsCount
+			) {
+				this.errorMessage = t('forms', 'You must rank all options')
+				return false
+			}
+
+			this.errorMessage = null
+			return true
+		},
+
 		/**
 		 * Initialize ranked/unranked options from existing values or default order
 		 */

src/views/Submit.vue

@@ -575,10 +575,12 @@ export default {
 					continue
 				}
 
-				answers[questionId] =
-					answer.type === 'QuestionMultiple'
-						? answer.value.map(String)
-						: answer.value
+				answers[questionId] = [
+					'QuestionMultiple',
+					'QuestionRanking',
+				].includes(answer.type)
+					? answer.value.map(String)
+					: answer.value
 			}
 			this.answers = answers
 		},