First draft.

index.js

@@ -0,0 +1,40 @@
+const core = require("@actions/core");
+const github = require("@actions/github");
+const { Octokit } = require("@octokit/rest");
+
+async function run() {
+  try {
+    const branch = core.getInput("branch");
+    const token = core.getInput("github_token");
+    const octokit = new Octokit({ auth: token });
+    const context = github.context;
+
+    // Check for existing PRs
+    const { data: pullRequests } = await octokit.rest.pulls.list({
+      owner: context.repo.owner,
+      repo: context.repo.repo,
+      head: `${context.repo.owner}:${branch}`,
+    });
+
+    if (pullRequests.length > 0) {
+      console.log("A pull request already exists for this branch.");
+      return;
+    }
+
+    // Creating a new PR
+    const newPr = await octokit.rest.pulls.create({
+      owner: context.repo.owner,
+      repo: context.repo.repo,
+      title: "Your PR Title", // Customize your PR title
+      head: branch,
+      base: "main", // Change this to your default branch if it's not 'main'
+      body: "Your PR description", // Customize your PR description
+    });
+
+    console.log(`Created a new pull request: ${newPr.data.html_url}`);
+  } catch (error) {
+    core.setFailed(`Action failed with error ${error}`);
+  }
+}
+
+run();