initial commit

src/main.ts

@@ -0,0 +1,182 @@
+import { readFileSync } from "fs";
+import * as core from "@actions/core";
+import { Configuration, OpenAIApi } from "openai";
+import { Octokit } from "@octokit/rest";
+import parseDiff, { Chunk, File } from "parse-diff";
+import minimatch from "minimatch";
+
+const GITHUB_TOKEN: string = core.getInput("GITHUB_TOKEN");
+const OPENAI_API_KEY: string = core.getInput("OPENAI_API_KEY");
+
+const octokit = new Octokit({ auth: GITHUB_TOKEN });
+
+const configuration = new Configuration({
+  apiKey: OPENAI_API_KEY,
+});
+
+const openai = new OpenAIApi(configuration);
+
+interface PRDetails {
+  owner: string;
+  repo: string;
+  pull_number: number;
+}
+
+async function getPRDetails(): Promise<PRDetails> {
+  const { repository, number } = JSON.parse(
+    readFileSync(process.env.GITHUB_EVENT_PATH || "", "utf8")
+  );
+  return {
+    owner: repository.owner.login,
+    repo: repository.name,
+    pull_number: number,
+  };
+}
+
+async function getDiff(
+  owner: string,
+  repo: string,
+  pull_number: number
+): Promise<string | null> {
+  const response = await octokit.pulls.get({
+    owner,
+    repo,
+    pull_number,
+    mediaType: { format: "diff" },
+  });
+  // @ts-expect-error - response.data is a string
+  return response.data;
+}
+
+async function analyzeCode(
+  parsedDiff: File[]
+): Promise<Array<{ body: string; path: string; line: number }>> {
+  const comments: Array<{ body: string; path: string; line: number }> = [];
+
+  for (const file of parsedDiff) {
+    for (const chunk of file.chunks) {
+      const prompt = createPrompt(file, chunk);
+      const aiResponse = await getAIResponse(prompt);
+      if (aiResponse) {
+        const comment = createComment(file, chunk, aiResponse);
+        if (comment) {
+          comments.push(comment);
+        }
+      }
+    }
+  }
+  return comments;
+}
+
+function createPrompt(file: File, chunk: Chunk): string {
+  return `
+Review the following code changes in the file "${
+    file.to
+  }" and provide comments and suggestions ONLY if there is something to improve. If the code looks good, DO NOT return any text (leave the response completely empty)
+
+${chunk.content}
+${chunk.changes
+  .map((c) => (c.type === "add" ? "+" : "-") + " " + c.content)
+  .join("\n")}
+`;
+}
+
+async function getAIResponse(prompt: string): Promise<string | null> {
+  const queryConfig = {
+    model: "gpt-4",
+    temperature: 0.2,
+    max_tokens: 400,
+    top_p: 1,
+    frequency_penalty: 0,
+    presence_penalty: 0,
+  };
+
+  try {
+    const response = await openai.createChatCompletion({
+      ...queryConfig,
+      messages: [
+        {
+          role: "system",
+          content: prompt,
+        },
+      ],
+    });
+
+    return response.data.choices[0].message?.content?.trim() || null;
+  } catch (error) {
+    console.error("Error:", error);
+    return null;
+  }
+}
+
+function createComment(
+  file: File,
+  chunk: Chunk,
+  aiResponse: string
+): { body: string; path: string; line: number } | null {
+  const lastAddChange = [...chunk.changes]
+    .reverse()
+    .find((c) => c.type === "add");
+  if (lastAddChange && file.to) {
+    return {
+      body: aiResponse,
+      path: file.to,
+      // @ts-expect-error below properties exists on AddChange
+      line: lastAddChange.ln || lastAddChange.ln1,
+    };
+  }
+  return null;
+}
+
+async function createReviewComment(
+  owner: string,
+  repo: string,
+  pull_number: number,
+  comments: Array<{ body: string; path: string; line: number }>
+): Promise<void> {
+  await octokit.pulls.createReview({
+    owner,
+    repo,
+    pull_number,
+    comments,
+    event: "COMMENT",
+  });
+}
+
+(async function main() {
+  const prDetails = await getPRDetails();
+  const diff = await getDiff(
+    prDetails.owner,
+    prDetails.repo,
+    prDetails.pull_number
+  );
+  if (!diff) {
+    console.log("No diff found");
+    return;
+  }
+
+  const parsedDiff = parseDiff(diff);
+  const excludePatterns = core
+    .getInput("exclude")
+    .split(",")
+    .map((s) => s.trim());
+
+  const filteredDiff = parsedDiff.filter((file) => {
+    return !excludePatterns.some((pattern) =>
+      minimatch(file.to ?? "", pattern)
+    );
+  });
+
+  const comments = await analyzeCode(filteredDiff);
+  if (comments.length > 0) {
+    await createReviewComment(
+      prDetails.owner,
+      prDetails.repo,
+      prDetails.pull_number,
+      comments
+    );
+  }
+})().catch((error) => {
+  console.error("Error:", error);
+  process.exit(1);
+});