infra: theme preview gh action (#296)

* chore: testing theme preview script

* fix: workflow

* test current pr

* comment on pr script

* fix: preview theme script

* fix: preview theme

scripts/preview-theme.js

@@ -0,0 +1,76 @@
+const core = require("@actions/core");
+const github = require("@actions/github");
+const parse = require("parse-diff");
+require("dotenv").config();
+
+const parsePullRequestId = (githubRef) => {
+  const result = /refs\/pull\/(\d+)\/merge/g.exec(githubRef);
+  if (!result) {
+    console.log("Reference not found.");
+    return 297;
+  }
+  const [, pullRequestId] = result;
+  return pullRequestId;
+};
+
+async function run() {
+  try {
+    const octokit = github.getOctokit(process.env.PERSONAL_TOKEN);
+    const pullRequestId = parsePullRequestId(process.env.GITHUB_REF);
+
+    let res = await octokit.pulls.get({
+      owner: "anuraghazra",
+      repo: "github-readme-stats",
+      pull_number: pullRequestId,
+      mediaType: {
+        format: "diff",
+      },
+    });
+
+    let diff = parse(res.data);
+    let colorStrings = diff
+      .find((file) => file.to === "themes/index.js")
+      .chunks[0].changes.filter((c) => c.type === "add")
+      .map((c) => c.content.replace("+", ""))
+      .join("");
+
+    let matches = colorStrings.match(/(title_color:.*bg_color.*\")/);
+    let colors = matches && matches[0].split(",");
+
+    if (!colors) {
+      await octokit.issues.createComment({
+        owner: "anuraghazra",
+        repo: "github-readme-stats",
+        body: `
+        \rTheme preview (bot)
+        Cannot create theme preview
+        `,
+        issue_number: pullRequestId,
+      });
+      return;
+    }
+    colors = colors.map((color) =>
+      color.replace(/.*\:\s/, "").replace(/\"/g, "")
+    );
+
+    let titleColor = colors[0];
+    let iconColor = colors[1];
+    let textColor = colors[2];
+    let bgColor = colors[3];
+    const url = `https://github-readme-stats.vercel.app/api?username=anuraghazra&title_color=${titleColor}&icon_color=${iconColor}&text_color=${textColor}&bg_color=${bgColor}&show_icons=true`;
+
+    await octokit.issues.createComment({
+      owner: "anuraghazra",
+      repo: "github-readme-stats",
+      body: `
+      \rTheme preview (bot)  
+      \r![](${url})
+      `,
+      issue_number: pullRequestId,
+    });
+  } catch (error) {
+    core.setFailed(error.message);
+  }
+}
+
+run();