import { debug, warning } from "@actions/core";
import { info } from "node:console";
import { existsSync, readFileSync, renameSync } from "node:fs";
import { resolve, basename } from "node:path";

export async function request(
  url: string,
  init?: RequestInit,
): Promise<Response> {
  const headers = new Headers(init?.headers);
  if (!headers.has("User-Agent")) {
    headers.set("User-Agent", "@oven-sh/setup-bun");
  }

  const res = await fetch(url, {
    ...init,
    headers,
  });
  if (!res.ok) {
    const body = await res.text().catch(() => "");
    throw new Error(
      `Failed to fetch url ${url}. (status code: ${res.status}, status text: ${res.statusText})${body ? `\n${body}` : ""}`,
    );
  }

  return res;
}

export function addExtension(path: string, ext: string): string {
  if (!path.endsWith(ext)) {
    renameSync(path, path + ext);
    return path + ext;
  }

  return path;
}

export function getPlatform(): string {
  const platform = process.platform;
  if (platform === "win32") return "windows";

  return platform;
}

export function getArchitecture(os: string, arch: string): string {
  if (os === "windows" && (arch === "aarch64" || arch === "arm64")) {
    warning(
      [
        "⚠️ Bun does not provide native arm64 builds for Windows.",
        "Using x64 baseline build which will run through Microsoft's x64 emulation layer.",
        "This may result in reduced performance and potential compatibility issues.",
        "💡 For best performance, consider using x64 Windows runners or other platforms with native support.",
      ].join("\n"),
    );

    return "x64";
  }

  if (arch === "arm64") return "aarch64";
  return arch;
}

export function getAvx2(os: string, arch: string, avx2?: boolean): boolean {
  // Temporary workaround for absence of arm64 builds on Windows (#130)
  if (os === "windows" && (arch === "aarch64" || arch === "arm64")) {
    return false;
  }

  return avx2 ?? true;
}

const FILE_VERSION_READERS = {
  "package.json": (content: string) => {
    const pkg = JSON.parse(content);
    return pkg.packageManager?.split("bun@")?.[1] ?? pkg.engines?.bun;
  },
  ".tool-versions": (content: string) =>
    content.match(/^bun\s*(?<version>.*?)$/m)?.groups?.version,
  ".bumrc": (content: string) => content, // https://github.com/owenizedd/bum
  ".bun-version": (content: string) => content,
};

export function readVersionFromFile(file: string): string | undefined {
  const cwd = process.env.GITHUB_WORKSPACE;
  if (!cwd) {
    return;
  }

  if (!file) {
    return;
  }

  debug(`Reading version from ${file}`);

  const path = resolve(cwd, file);
  const base = basename(file);

  if (!existsSync(path)) {
    warning(`File ${path} not found`);
    return;
  }

  const reader = FILE_VERSION_READERS[base] ?? (() => undefined);

  let output: string | undefined;
  try {
    output = reader(readFileSync(path, "utf8"))?.trim();

    if (!output) {
      warning(`Failed to read version from ${file}`);
      return;
    }
  } catch (error) {
    const { message } = error as Error;
    warning(`Failed to read ${file}: ${message}`);
  } finally {
    if (output) {
      info(`Obtained version ${output} from ${file}`);
      return output;
    }
  }
}