// src/platform.ts
import { Gitea } from '@go-gitea/sdk.js';
import github from '@actions/github';
import { PushEvent } from '@octokit/webhooks-types';

export const REWRITE_MARKER = '[OPENCOMMIT]';

export type NormalizedCommit = {
  id: string;
  message: string;
  author?: { name?: string; email?: string };
};

export function isGitea(): boolean {
  return !!process.env.GITEA_BASE_URL;
}

export async function getPushCommits(): Promise<NormalizedCommit[]> {
  if (isGitea()) {
    const payload = github.context.payload as any;
    const commits = payload.commits as Array<any>;

    return commits
      .filter((commit) => {
        if (commit.message.startsWith('Merge')) return false;
        if (commit.message.includes(REWRITE_MARKER)) return false;
        return true;
      })
      .map((commit) => ({
        id: commit.id,
        message: commit.message,
        author: commit.author
          ? {
              name: commit.author.name,
              email: commit.author.email ?? undefined, // coerce null → undefined
            }
          : undefined,
      }));
  } else {
    const payload = github.context.payload as PushEvent;
    const commits = payload.commits;

    return commits
      .filter((commit) => {
        if (commit.message.startsWith('Merge')) return false;
        if (commit.message.includes(REWRITE_MARKER)) return false;
        return true;
      })
      .map((commit) => ({
        id: commit.id,
        message: commit.message,
        author: {
          name: commit.author.name,
          email: commit.author.email ?? undefined, // coerce null → undefined
        },
      }));
  }
}

export async function fetchCommitDiff(
  sha: string,
  giteaConfig?: { baseUrl: string; token: string }
): Promise<{ sha: string; diff: string }> {
  if (isGitea() && giteaConfig) {
    const gitea = new Gitea({
      baseUrl: giteaConfig.baseUrl,
      auth: giteaConfig.token,
    });

    const { data } = await gitea.rest.git.getCommit({
      owner: process.env.GITEA_REPO_OWNER!,
      repo: process.env.GITEA_REPO_NAME!,
      sha,
    });

    const filesChanged =
      data.files?.map((f: any) => `diff --git a/${f.filename} b/${f.filename}`).join('\n') ?? '';

    return { sha, diff: filesChanged };
  } else {
    const octokit = github.getOctokit(process.env.GITHUB_TOKEN!);
    const context = github.context;

    const { data: diff } = await octokit.request<string>(
      'GET /repos/{owner}/{repo}/commits/{ref}',
      {
        owner: context.repo.owner,
        repo: context.repo.repo,
        ref: sha,
        headers: { Accept: 'application/vnd.github.v3.diff' },
      }
    );

    return { sha, diff };
  }
}