Conditional questions: branches on file upload

docs/DataStructure.md

@@ -307,6 +307,7 @@ Follow-up questions (subquestions) are questions of their own with additional pr
 | `date`            | `date_range`      | Date - range including its bounds (`YYYY-MM-DD`) |
 | `datetime`        | `date_range`      | Deprecated date and time (`YYYY-MM-DD HH:mm`) |
 | `time`            | `date_range`      | Time - range including its bounds (`HH:mm`) |
+| `file`            | `file_uploaded`   | File - whether a file was uploaded  |
 
 A branch is shown when any of its conditions matches. Several branches can be shown at once.
 
@@ -368,6 +369,14 @@ All options in `optionIds` must be selected for the condition to match.
 
 `min` and `max` use the answer format of the question type and are optional.
 
+#### file_uploaded (for file)
+
+```json
+{ "type": "file_uploaded", "fileUploaded": true }
+```
+
+`"fileUploaded": false` matches when no file was uploaded.
+
 ### Example
 
 A dropdown question with a branch of follow-up questions:

lib/Constants.php

@@ -245,6 +245,7 @@ class Constants {
 	public const CONDITION_TYPE_OPTION_SELECTED = 'option_selected';
 	public const CONDITION_TYPE_OPTIONS_COMBINATION = 'options_combination';
 	public const CONDITION_TYPE_DATE_RANGE = 'date_range';
+	public const CONDITION_TYPE_FILE_UPLOADED = 'file_uploaded';
 
 	/**
 	 * Question types that can have branches with follow-up questions in `extraSettings.branches`,
@@ -259,6 +260,7 @@ class Constants {
 		self::ANSWER_TYPE_DATE => [self::CONDITION_TYPE_DATE_RANGE],
 		self::ANSWER_TYPE_DATETIME => [self::CONDITION_TYPE_DATE_RANGE],
 		self::ANSWER_TYPE_TIME => [self::CONDITION_TYPE_DATE_RANGE],
+		self::ANSWER_TYPE_FILE => [self::CONDITION_TYPE_FILE_UPLOADED],
 	];
 
 	/**

lib/Service/SubmissionService.php

@@ -1049,8 +1049,8 @@ private function evaluateBranchConditions(string $triggerType, array $triggerAns
 		// Option ids arrive as numbers or strings depending on the trigger component
 		$selectedOptionIds = array_map('strval', array_filter($triggerAnswer, 'is_scalar'));
 
-		// An unanswered trigger activates no branch
-		if ($triggerAnswer === [] || ($triggerAnswer[0] ?? '') === '') {
+		// An unanswered trigger activates no branch, except "no file uploaded" for file triggers
+		if ($triggerType !== Constants::ANSWER_TYPE_FILE && ($triggerAnswer === [] || ($triggerAnswer[0] ?? '') === '')) {
 			return false;
 		}
 
@@ -1077,6 +1077,14 @@ private function evaluateBranchConditions(string $triggerType, array $triggerAns
 					}
 				}
 				return false;
+			case Constants::ANSWER_TYPE_FILE:
+				$hasFile = !empty($triggerAnswer);
+				foreach ($conditions as $condition) {
+					if (($condition['fileUploaded'] ?? true) === $hasFile) {
+						return true;
+					}
+				}
+				return false;
 			case Constants::ANSWER_TYPE_DATE:
 			case Constants::ANSWER_TYPE_DATETIME:
 			case Constants::ANSWER_TYPE_TIME:

src/components/Conditional/BranchConditionEditor.vue

@@ -50,19 +50,32 @@
 					class="condition-date-input" />
 			</div>
 		</template>
+
+		<!-- File-based conditions -->
+		<template v-else-if="triggerType === 'file'">
+			<div class="condition-row">
+				<NcCheckboxRadioSwitch
+					:modelValue="fileUploadedCondition"
+					@update:modelValue="onFileConditionChange">
+					{{ t('forms', 'File is uploaded') }}
+				</NcCheckboxRadioSwitch>
+			</div>
+		</template>
 	</div>
 </template>
 
 <script>
 import { t } from '@nextcloud/l10n'
 import moment from '@nextcloud/moment'
+import NcCheckboxRadioSwitch from '@nextcloud/vue/components/NcCheckboxRadioSwitch'
 import NcDateTimePicker from '@nextcloud/vue/components/NcDateTimePicker'
 import NcSelect from '@nextcloud/vue/components/NcSelect'
 
 export default {
 	name: 'BranchConditionEditor',
 
 	components: {
+		NcCheckboxRadioSwitch,
 		NcDateTimePicker,
 		NcSelect,
 	},
@@ -236,6 +249,13 @@ export default {
 			},
 		},
 
+		/**
+		 * File uploaded condition
+		 */
+		fileUploadedCondition() {
+			return this.branch.conditions?.[0]?.fileUploaded ?? true
+		},
+
 		/**
 		 * Date picker type based on trigger type
 		 */
@@ -288,6 +308,16 @@ export default {
 			this.emitUpdate({ conditions })
 		},
 
+		/**
+		 * Handle file condition change
+		 *
+		 * @param {boolean} checked Whether file is uploaded condition is checked
+		 */
+		onFileConditionChange(checked) {
+			const conditions = [{ fileUploaded: checked }]
+			this.emitUpdate({ conditions })
+		},
+
 		/**
 		 * Update a condition property
 		 *

src/components/Questions/QuestionFile.vue

@@ -151,6 +151,7 @@
 			</ul>
 		</div>
 		<template #insert>
+			<slot name="branches" />
 			<slot name="insert" />
 		</template>
 	</Question>

src/utils/Branches.ts

@@ -21,6 +21,7 @@ const BRANCH_MATCHERS: Record<string, BranchMatcher> = {
 	date: matchDateRange,
 	datetime: matchDateRange,
 	time: matchDateRange,
+	file: matchFileUploaded,
 }
 
 /**
@@ -76,6 +77,22 @@ function matchDateRange(
 	)
 }
 
+/**
+ * Files match if a condition is about the upload state of the answer, also "no file uploaded"
+ *
+ * @param conditions the conditions of the branch
+ * @param values the answer of the question
+ */
+function matchFileUploaded(
+	conditions: Record<string, unknown>[],
+	values: string[],
+): boolean {
+	const hasFile = values.length > 0 && values[0] !== ''
+	return conditions.some(
+		(condition) => (condition.fileUploaded ?? true) === hasFile,
+	)
+}
+
 /**
  * @param type the question type
  */
@@ -111,7 +128,7 @@ export function persistedSettings<T extends Record<string, unknown>>(
 }
 
 /**
- * Branches the answer activates, an unanswered question activates none
+ * Branches the answer activates, an unanswered question activates none except "no file uploaded"
  *
  * @param question the question with the branches
  * @param values the answer of the question
@@ -122,7 +139,10 @@ export function getActiveBranches(
 ): FormsConditionalBranch[] {
 	const matcher = BRANCH_MATCHERS[question.type]
 	const answer = Array.isArray(values) ? values.map(String) : []
-	if (!matcher || answer.length === 0 || answer[0] === '') {
+	if (
+		!matcher
+		|| (question.type !== 'file' && (answer.length === 0 || answer[0] === ''))
+	) {
 		return []
 	}
 	return getBranches(question).filter(

tests/Unit/Service/FormsServiceTest.php

@@ -1935,6 +1935,11 @@ public static function dataAreExtraSettingsValid() {
 				'questionType' => Constants::ANSWER_TYPE_TIME,
 				'expected' => true
 			],
+			'valid-branches-file-uploaded' => [
+				'extraSettings' => ['branches' => [['id' => 'branch-1', 'conditions' => [['type' => 'file_uploaded', 'fileUploaded' => false]]]]],
+				'questionType' => Constants::ANSWER_TYPE_FILE,
+				'expected' => true
+			],
 			'valid-branches-with-own-settings' => [
 				'extraSettings' => ['shuffleOptions' => true, 'branches' => [['id' => 'branch-1', 'conditions' => [['type' => 'option_selected', 'optionId' => 1]]]]],
 				'questionType' => Constants::ANSWER_TYPE_DROPDOWN,

tests/Unit/Service/SubmissionServiceTest.php

@@ -1755,6 +1755,35 @@ public static function dataValidateSubmission() {
 				// Expected Result
 				null,
 			],
+			'invalid-branch-no-file-uploaded' => [
+				// Questions - an unanswered file question opens its "no file uploaded" branch
+				[
+					[
+						'id' => 100,
+						'type' => Constants::ANSWER_TYPE_FILE,
+						'text' => 'File Q',
+						'isRequired' => false,
+						'extraSettings' => [
+							'branches' => [
+								[
+									'id' => 'branch-no-file',
+									'conditions' => [['type' => 'file_uploaded', 'fileUploaded' => false]],
+									'subQuestions' => [['id' => 101, 'type' => 'short', 'text' => 'Why no file?', 'isRequired' => true]],
+								],
+								[
+									'id' => 'branch-file',
+									'conditions' => [['type' => 'file_uploaded', 'fileUploaded' => true]],
+									'subQuestions' => [['id' => 102, 'type' => 'short', 'text' => 'About the file', 'isRequired' => true]],
+								],
+							],
+						],
+					],
+				],
+				// Answers - nothing uploaded
+				[],
+				// Expected Result
+				'Question "Why no file?" is required.',
+			],
 			'invalid-branch-unknown-option' => [
 				// Questions - The question is validated like any other question
 				[