import { execSync } from "child_process";
import { join } from "path";

export interface GitContext {
  available: boolean;
  repoRoot: string | null;
  branch: string | null;
  recentCommit: string | null;
  status: string | null;
}

export function collectGitContext(workspaceRoot: string): GitContext {
  try {
    const gitDir = execSync("git rev-parse --show-toplevel 2>/dev/null", {
      cwd: workspaceRoot,
      encoding: "utf-8",
      timeout: 5000,
    }).trim();

    if (!gitDir) {
      return { available: false, repoRoot: null, branch: null, recentCommit: null, status: null };
    }

    const branch = execSync("git rev-parse --abbrev-ref HEAD 2>/dev/null", {
      cwd: gitDir,
      encoding: "utf-8",
      timeout: 5000,
    }).trim();

    const recentCommit = execSync("git log -1 --oneline 2>/dev/null", {
      cwd: gitDir,
      encoding: "utf-8",
      timeout: 5000,
    }).trim();

    let status: string | null = null;
    try {
      const raw = execSync("git status --short 2>/dev/null", {
        cwd: gitDir,
        encoding: "utf-8",
        timeout: 5000,
      }).trim();
      if (raw) {
        const lines = raw.split("\n").slice(0, 30);
        status = lines.join("\n");
        if (raw.split("\n").length > 30) {
          status += `\n... ${raw.split("\n").length - 30} more files`;
        }
      }
    } catch {
      // status unavailable, non-critical
    }

    return { available: true, repoRoot: gitDir, branch, recentCommit, status };
  } catch {
    return { available: false, repoRoot: null, branch: null, recentCommit: null, status: null };
  }
}