Add prepare-commit-msg commit message hook

hellotech/.config/git/config-hellotech

@@ -1,3 +1,5 @@
 [url "git@github.com:HelloTech"]
 	insteadOf = https://github.com/HelloTech
 	email = buddy@hellotech.com
+[init]
+	templateDir = ~/.config/git/template

hellotech/.config/git/template/hooks/prepare-commit-msg

@@ -0,0 +1,37 @@
+#!/usr/bin/env node
+
+const fs = require("fs");
+const childProcess = require("child_process");
+const { promisify } = require("util");
+
+const exec = promisify(childProcess.exec);
+const readFile = promisify(fs.readFile);
+const writeFile = promisify(fs.writeFile);
+
+const [, , commitMsg, comitSrc, sha1] = process.argv;
+
+async function main() {
+  const file = await readFile(commitMsg, { encoding: "utf8" });
+  const result = await exec("git symbolic-ref --short HEAD");
+
+  const tags = result.stdout
+    .split("\n")
+    .map(branch => branch.match(/[A-Z]+-\d+/g))
+    .filter(x => !!x)
+    .reduce((allIDs, matchedIDs) => [...allIDs, ...matchedIDs], [])
+    .map(id => `[${id}]`);
+
+  if (tags.length === 0) {
+    return;
+  }
+  if (tags.find(tag => file.includes(tag))) {
+    return;
+  }
+  const newFile = "\n\n# " + tags.join(" ") + "\n" + file;
+  await writeFile(commitMsg, newFile);
+}
+
+main().catch(err => {
+  console.error(err);
+  process.exit(1);
+});