Add commit detail view

Signed-off-by: Sebastian Martinez <sebastinez@me.com>

src/commit.ts

@@ -0,0 +1,110 @@
+import type { Stats } from "@app/project";
+import type { Diff } from "@app/diff";
+
+export interface CommitsHistory {
+  headers: CommitHeader[];
+  stats: Stats;
+}
+export interface GroupedCommitsHistory {
+  headers: CommitGroup[];
+  stats: Stats;
+}
+
+export interface Author {
+  avatar: string;
+  email: string;
+  name: string;
+}
+
+export interface CommitStats {
+  branches: number;
+  commits: number;
+  contributors: number;
+}
+
+export interface GroupedCommitsHistory {
+  headers: CommitGroup[];
+  stats: Stats;
+}
+
+export interface CommitHeader {
+  author: Author;
+  committer: Author;
+  committerTime: number;
+  description: string;
+  sha1: string;
+  summary: string;
+}
+
+// A set of commits grouped by time.
+export interface CommitGroup {
+  time: string;
+  commits: CommitHeader[];
+}
+
+export interface CommitStats {
+  additions: number;
+  deletions: number;
+}
+
+export interface Commit {
+  header: CommitHeader;
+  stats: CommitStats;
+  diff: Diff;
+  branches: string[];
+}
+
+export function formatGroupTime(timestamp: number): string {
+  return new Date(timestamp).toLocaleDateString("en-US", {
+    day: 'numeric',
+    weekday: 'long',
+    month: 'long',
+    year: 'numeric'
+  });
+}
+
+export const groupCommitHistory = (
+  history: CommitsHistory
+): GroupedCommitsHistory => {
+  return { ...history, headers: groupCommits(history.headers) };
+};
+
+export function groupCommits(commits: CommitHeader[]): CommitGroup[] {
+  const groupedCommits: CommitGroup[] = [];
+  let groupDate: Date | undefined = undefined;
+
+  commits = commits.sort((a, b) => {
+    if (a.committerTime > b.committerTime) {
+      return -1;
+    } else if (a.committerTime < b.committerTime) {
+      return 1;
+    }
+
+    return 0;
+  });
+
+  for (const commit of commits) {
+    const time = commit.committerTime * 1000;
+    const date = new Date(time);
+    const isNewDay =
+      !groupedCommits.length ||
+      !groupDate ||
+      date.getDate() < groupDate.getDate() ||
+      date.getMonth() < groupDate.getMonth() ||
+      date.getFullYear() < groupDate.getFullYear();
+
+    if (isNewDay) {
+      groupedCommits.push({
+        time: formatGroupTime(time),
+        commits: [],
+      });
+      groupDate = date;
+    }
+    groupedCommits[groupedCommits.length - 1].commits.push(commit);
+  }
+  return groupedCommits;
+}
+
+export const formatCommitTime = (t: number): string => {
+  return new Date(t * 1000).toUTCString();
+};