From 6ba700165964b79ceb2ea7ccca4a805046bdc610 Mon Sep 17 00:00:00 2001
From: Marley Powell <Marley.Powell@exclaimer.com>
Date: Thu, 11 Nov 2021 12:19:01 +0000
Subject: [PATCH] feat: Created `utils` file for util functions.

Signed-off-by: Marley Powell <Marley.Powell@exclaimer.com>
---
 .../PullRequestCardReviewers.tsx              |  13 +-
 .../components/PullRequestsPage/lib/utils.ts  | 117 ++++++++++++++++++
 2 files changed, 119 insertions(+), 11 deletions(-)
 create mode 100644 plugins/azure-devops/src/components/PullRequestsPage/lib/utils.ts

diff --git a/plugins/azure-devops/src/components/PullRequestsPage/lib/PullRequestCard/PullRequestCardReviewers.tsx b/plugins/azure-devops/src/components/PullRequestsPage/lib/PullRequestCard/PullRequestCardReviewers.tsx
index a3b87e0439..2a9a265756 100644
--- a/plugins/azure-devops/src/components/PullRequestsPage/lib/PullRequestCard/PullRequestCardReviewers.tsx
+++ b/plugins/azure-devops/src/components/PullRequestsPage/lib/PullRequestCard/PullRequestCardReviewers.tsx
@@ -14,13 +14,10 @@
  * limitations under the License.
  */
 
-import {
-  PullRequestVoteStatus,
-  Reviewer,
-} from '@backstage/plugin-azure-devops-common';
-
 import { PullRequestCardReviewer } from './PullRequestCardReviewer';
 import React from 'react';
+import { Reviewer } from '@backstage/plugin-azure-devops-common';
+import { reviewerFilter } from '../utils';
 import { styled } from '@material-ui/core/styles';
 
 const PullRequestCardReviewersContainer = styled('div')({
@@ -43,9 +40,3 @@ export const PullRequestCardReviewers = ({
     ))}
   </PullRequestCardReviewersContainer>
 );
-
-function reviewerFilter(reviewer: Reviewer): boolean {
-  return reviewer.voteStatus === PullRequestVoteStatus.NoVote
-    ? !!reviewer.isRequired
-    : !reviewer.isContainer;
-}
diff --git a/plugins/azure-devops/src/components/PullRequestsPage/lib/utils.ts b/plugins/azure-devops/src/components/PullRequestsPage/lib/utils.ts
new file mode 100644
index 0000000000..c9cf866010
--- /dev/null
+++ b/plugins/azure-devops/src/components/PullRequestsPage/lib/utils.ts
@@ -0,0 +1,117 @@
+/*
+ * Copyright 2021 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {
+  DashboardPullRequest,
+  PullRequestVoteStatus,
+  Reviewer,
+} from '@backstage/plugin-azure-devops-common';
+import {
+  PullRequestFilter,
+  PullRequestGroup,
+  PullRequestGroupConfig,
+} from './types';
+
+/**
+ * Creates a filter that matches pull requests created by `userEmail`.
+ * @param userEmail an email to filter by.
+ * @returns a filter for pull requests created by `userEmail`.
+ */
+export function getCreatedByUserFilter(
+  userEmail: string | undefined,
+): PullRequestFilter {
+  return (pullRequest: DashboardPullRequest): boolean =>
+    pullRequest.createdBy?.uniqueName?.toLocaleLowerCase() ===
+    userEmail?.toLocaleLowerCase();
+}
+
+/**
+ * Filters a reviewer based on vote status and if the reviewer is required.
+ * @param reviewer a reviewer to filter.
+ * @returns whether or not to filter the `reviewer`.
+ */
+export function reviewerFilter(reviewer: Reviewer): boolean {
+  return reviewer.voteStatus === PullRequestVoteStatus.NoVote
+    ? !!reviewer.isRequired
+    : !reviewer.isContainer;
+}
+
+/**
+ * Removes values from the provided array and returns them.
+ * @param arr the array to extract values from.
+ * @param filter a filter used to extract values from the provided array.
+ * @returns the values that were extracted from the array.
+ *
+ * @example
+ * ```ts
+ * const numbers = [1, 2, 3, 4, 5, 6];
+ * const numberFilter = (num: number): boolean => num > 3;
+ * const extractedNumbers = arrayExtract(numbers, numberFilter);
+ * console.log(numbers); // [1, 2, 3]
+ * console.log(extractedNumbers); // [4, 5, 6]
+ * ```
+ *
+ * @example
+ * ```ts
+ * const numbers = [1, 2, 3, 4, 5, 6];
+ * const numberFilter = (num: number): boolean => num % 2 === 0;
+ * const extractedNumbers = arrayExtract(numbers, numberFilter);
+ * console.log(numbers); // [1, 3, 5]
+ * console.log(extractedNumbers); // [2, 4, 6]
+ * ```
+ */
+export function arrayExtract<T>(arr: T[], filter: (value: T) => unknown): T[] {
+  const extractedValues: T[] = [];
+
+  for (let i = 0; i - extractedValues.length < arr.length; i++) {
+    const offsetIndex = i - extractedValues.length;
+
+    const value = arr[offsetIndex];
+
+    if (filter(value)) {
+      arr.splice(offsetIndex, 1);
+      extractedValues.push(value);
+    }
+  }
+
+  return extractedValues;
+}
+
+/**
+ * Creates groups of pull requests based on a list of `PullRequestGroupConfig`.
+ * @param pullRequests all pull requests to be split up into groups.
+ * @param configs the config used for splitting up the pull request groups.
+ * @returns a list of pull request groups.
+ */
+export function getPullRequestGroups(
+  pullRequests: DashboardPullRequest[],
+  configs: PullRequestGroupConfig[],
+): PullRequestGroup[] {
+  const remainingPullRequests: DashboardPullRequest[] = [...pullRequests];
+  const pullRequestGroups: PullRequestGroup[] = [];
+
+  configs.forEach(({ title, filter: configFilter, simplified }) => {
+    const groupPullRequests = arrayExtract(remainingPullRequests, configFilter);
+
+    pullRequestGroups.push({
+      title,
+      pullRequests: groupPullRequests,
+      simplified,
+    });
+  });
+
+  return pullRequestGroups;
+}