// The agent phase's environment and the helpers every agent runner shares. It
// is read once, when the runner starts, as the single-file runner did.
import { chmod, chown, writeFile } from "node:fs/promises";
import process from "node:process";

import { agentCommand } from "./isolation.ts";
import { agentEnvironment, sanitizedEnvironment } from "./profiles.ts";
import { readRuntimeManifest } from "./runtime.ts";
import type { RuntimeProfile } from "./runtime.ts";

export const env = (name: string): string => {
  const value = process.env[name];
  if (value === undefined) {
    throw new Error(`${name} is not set`);
  }
  return value;
};

function definedEnvironment(): Record<string, string> {
  const result: Record<string, string> = {};
  for (const [name, value] of Object.entries(process.env)) {
    if (value !== undefined) {
      result[name] = value;
    }
  }
  return result;
}

export const API = env("GITEA_API_URL");
export const REPO = env("GITEA_REPOSITORY");
export const INDEX = env("ISSUE_INDEX");
export const EVENT = env("EVENT_NAME");
const AUTHOR_TOKEN = env("GITEA_TOKEN");
export const WORKSPACE = env("GITHUB_WORKSPACE");
export const MANIFEST = await readRuntimeManifest(env("BOT_AGENTS_MANIFEST"));
export const PROCESS_ENV = sanitizedEnvironment(definedEnvironment());

export async function gitea(path: string, body?: unknown): Promise<Response> {
  const response = await fetch(`${API}/${path}`, {
    method: body === undefined ? "GET" : "POST",
    headers: {
      Authorization: `token ${AUTHOR_TOKEN}`,
      "Content-Type": "application/json",
    },
    body: body === undefined ? null : JSON.stringify(body),
  });
  if (!response.ok) {
    throw new Error(`${path}: ${response.status} ${await response.text()}`);
  }
  return response;
}

export async function postAuthorComment(body: string): Promise<void> {
  await gitea(`repos/${REPO}/issues/${INDEX}/comments`, { body });
}

export async function runAgentCommand(
  profile: RuntimeProfile,
  command: string,
  args: string[],
  token?: string,
): Promise<void> {
  const { success, code } = await agentCommand(profile, command, args, {
    cwd: WORKSPACE,
    env: agentEnvironment(PROCESS_ENV, profile, token),
    clearEnv: true,
  }).output();
  if (!success) {
    throw new Error(`${command} ${args[0]} exited with ${code}`);
  }
}

export async function makeProfileFile(profile: RuntimeProfile, name: string): Promise<string> {
  const path = `${profile.home}/${name}`;
  await writeFile(path, "", { mode: 0o600 });
  await chmod(path, 0o600);
  await chown(path, profile.uid, profile.gid);
  return path;
}