import fs from "node:fs/promises";
import path from "node:path";
import fg from "fast-glob";
import type { VersionFinding } from "./shared";

const FRONTMATTER_RE = /^---\n([\s\S]*?)^---$/m;
const ERP_KIT_VERSION_RE = /^\s*erp-kit-version:\s*"([^"]+)"$/m;

export async function checkSkillsVersion(
  cwd: string,
  installedVersion: string,
): Promise<VersionFinding[]> {
  const skillFiles = await fg([".agents/skills/erp-kit-*/SKILL.md"], {
    cwd,
    onlyFiles: true,
    dot: true,
    ignore: ["**/node_modules/**"],
  });
  const results = await Promise.all(
    skillFiles.map(async (relativePath): Promise<VersionFinding | undefined> => {
      const content = await fs.readFile(path.join(cwd, relativePath), "utf8");
      const frontmatterMatch = content.match(FRONTMATTER_RE);
      const versionMatch = frontmatterMatch?.[1].match(ERP_KIT_VERSION_RE);
      if (!versionMatch) {
        return {
          severity: "error",
          check: "skills-version",
          subject: relativePath,
          message: `metadata.erp-kit-version frontmatter is missing; run \`erp-kit update skills\` to regenerate.`,
        };
      }
      const recordedVersion = versionMatch[1];
      if (recordedVersion === "0.0.0") {
        return {
          severity: "info",
          check: "skills-version",
          subject: relativePath,
          message: `recorded erp-kit version ${recordedVersion} is the unpublished placeholder (expected only in the erp-kit dev repo).`,
        };
      }
      if (recordedVersion === installedVersion) return undefined;
      return {
        severity: "error",
        check: "skills-version",
        subject: relativePath,
        message: `generated for erp-kit ${recordedVersion}, but installed erp-kit is ${installedVersion}. Run \`erp-kit update skills\` to refresh.`,
      };
    }),
  );
  return results.filter((f): f is VersionFinding => f !== undefined);
}