import path from "node:path";
import yaml from "js-yaml";
import fs from "node:fs";
import fsp from "node:fs/promises";

import {
  type Tool,
  type PackageJSON,
  type Packages,
  InvalidMonorepoError,
} from "./Tool.ts";
import {
  expandPackageGlobs,
  expandPackageGlobsSync,
} from "./expandPackageGlobs.ts";
import { readJson, readJsonSync } from "./utils.ts";

async function readYamlFile<T = unknown>(path: string): Promise<T> {
  return fsp
    .readFile(path, "utf8")
    .then((data) => yaml.load(data)) as Promise<T>;
}
function readYamlFileSync<T = unknown>(path: string): T {
  return yaml.load(fs.readFileSync(path, "utf8")) as T;
}

export const PnpmTool: Tool = {
  type: "pnpm",

  async isMonorepoRoot(directory: string): Promise<boolean> {
    try {
      const manifest = await readYamlFile<{ packages?: string[] }>(
        path.join(directory, "pnpm-workspace.yaml")
      );

      if (manifest.packages) {
        return true;
      }
    } catch (err) {
      if (err && (err as { code: string }).code === "ENOENT") {
        return false;
      }
      throw err;
    }
    return false;
  },

  isMonorepoRootSync(directory: string): boolean {
    try {
      const manifest = readYamlFileSync<{ packages?: string[] }>(
        path.join(directory, "pnpm-workspace.yaml")
      );

      if (manifest.packages) {
        return true;
      }
    } catch (err) {
      if (err && (err as { code: string }).code === "ENOENT") {
        return false;
      }
      throw err;
    }
    return false;
  },

  async getPackages(directory: string): Promise<Packages> {
    const rootDir = path.resolve(directory);

    try {
      const manifest = await readYamlFile<{ packages?: string[] }>(
        path.join(rootDir, "pnpm-workspace.yaml")
      );
      const pkgJson = (await readJson(rootDir, "package.json")) as PackageJSON;
      const packageGlobs: string[] = manifest.packages!;

      return {
        tool: PnpmTool,
        packages: await expandPackageGlobs(packageGlobs, rootDir),
        rootPackage: {
          dir: rootDir,
          relativeDir: ".",
          packageJson: pkgJson,
        },
        rootDir,
      };
    } catch (err) {
      if (err && (err as { code: string }).code === "ENOENT") {
        throw new InvalidMonorepoError(
          `Directory ${rootDir} is not a valid ${PnpmTool.type} monorepo root: missing pnpm-workspace.yaml and/or package.json`
        );
      }
      throw err;
    }
  },

  getPackagesSync(directory: string): Packages {
    const rootDir = path.resolve(directory);

    try {
      const manifest = readYamlFileSync<{ packages?: string[] }>(
        path.join(rootDir, "pnpm-workspace.yaml")
      );
      const pkgJson = readJsonSync(rootDir, "package.json") as PackageJSON;
      const packageGlobs: string[] = manifest.packages!;

      return {
        tool: PnpmTool,
        packages: expandPackageGlobsSync(packageGlobs, rootDir),
        rootPackage: {
          dir: rootDir,
          relativeDir: ".",
          packageJson: pkgJson,
        },
        rootDir: rootDir,
      };
    } catch (err) {
      if (err && (err as { code: string }).code === "ENOENT") {
        throw new InvalidMonorepoError(
          `Directory ${rootDir} is not a valid ${PnpmTool.type} monorepo root: missing pnpm-workspace.yaml and/or package.json`
        );
      }
      throw err;
    }
  },
};