import { Octokit } from "octokit";
import { execSync } from "node:child_process";

// Typescript 4 will support it natively, but not yet :(
type Await<T> = T extends PromiseLike<infer U> ? U : T;
type Commits = Await<ReturnType<Octokit["rest"]["repos"]["compareCommits"]>>["data"]["commits"];

export function getCompareLink(packageName: string, previousTag: string, newTag: string) {
  const previousPackage = execSync(
    `git show ${previousTag}:../operator/Cargo.lock | grep -E '${packageName}(\\.git)?\\?' | head -1 | grep -o '".*"'`
  ).toString();
  const previousCommit = /#([0-9a-f]*)/g.exec(previousPackage)[1].slice(0, 8);
  const previousRepo = /(https:\/\/.*)\?/g.exec(previousPackage)[1];

  const newPackage = execSync(
    `git show ${newTag}:../operator/Cargo.lock | grep -E '${packageName}(\\.git)?\\?' | head -1 | grep -o '".*"'`
  ).toString();
  const newCommit = /#([0-9a-f]*)/g.exec(newPackage)[1].slice(0, 8);
  const newRepo = /(https:\/\/.*)\?/g.exec(newPackage)[1];
  const newRepoOrganization = /github.com\/([^\/]*)/g.exec(newRepo)[1];

  const diffLink =
    previousRepo !== newRepo
      ? `${previousRepo}/compare/${previousCommit}...${newRepoOrganization}:${newCommit}`
      : `${previousRepo}/compare/${previousCommit}...${newCommit}`;

  return diffLink;
}

export async function getCommitAndLabels(
  octokit: Octokit,
  owner: string,
  repo: string,
  previousTag: string,
  newTag: string
): Promise<{ prByLabels: any; commits: any[] }> {
  let commits: Commits = [];
  let more = true;
  let page = 0;
  while (more) {
    const compare = await octokit.rest.repos.compareCommitsWithBasehead({
      owner,
      repo,
      basehead: previousTag + "..." + newTag,
      per_page: 200,
      page,
    });
    commits = commits.concat(compare.data.commits);
    more = compare.data.commits.length === 200;
    page++;
  }

  // Determine commits to exclude
  // - commits reverted in the same range
  const excludedCommits: number[] = [];
  const revertedCommits: number[] = [];
  for (let i = commits.length - 1; i >= 0; i--) {
    const commitMessageFirstLine = commits[i].commit.message.split("\n")[0].trim();

    if (revertedCommits[commitMessageFirstLine] != null) {
      excludedCommits.push(i);
      excludedCommits.push(revertedCommits[commitMessageFirstLine]);
    } else {
      const foundRevertedCommitName = commitMessageFirstLine.match(/Revert \"(.*)\"/);
      if (foundRevertedCommitName?.length > 0) {
        revertedCommits[foundRevertedCommitName[1]] = i;
      }
    }
  }

  const prByLabels = {};
  for (let i = 0; i < commits.length; i++) {
    const commitMessageFirstLine = commits[i].commit.message.split("\n")[0].trim();
    if (!excludedCommits.includes(i)) {
      const foundPrsNumbers = commitMessageFirstLine.match(/\(#([0-9]+)\)$/);
      if (foundPrsNumbers && foundPrsNumbers.length > 1) {
        // This will check current repo and if the PR is not found, will try the official repo
        const repos = [
          { owner, repo },
          { owner: "datahaven-xyz", repo: "datahaven" },
        ];
        for (const { owner, repo } of repos) {
          try {
            const pr = await octokit.rest.pulls.get({
              owner,
              repo,
              pull_number: parseInt(foundPrsNumbers[1]),
            });

            if (pr.data.labels && pr.data.labels.length > 0) {
              for (const label of pr.data.labels) {
                prByLabels[label.name] = prByLabels[label.name] || [];
                prByLabels[label.name].push(pr.data);
              }
            } else {
              prByLabels[""] = prByLabels[""] || [];
              prByLabels[""].push(pr);
            }
            break;
          } catch (e) {
            // PR not found... let's try the other repo
          }
        }
      }
    }
  }
  return {
    prByLabels,
    commits,
  };
}