/**
 * Load central fleet.json + per-service JSON configs.
 * @module load
 */

import fs from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import { loadMachines } from './machines.js';

const HERE = path.dirname(fileURLToPath(import.meta.url));
export const FLEET_ROOT = path.resolve(HERE, '..');

export function readJson(file) {
  return JSON.parse(fs.readFileSync(file, 'utf8'));
}

/**
 * @param {string} [root]
 */
export function loadFleet(root = FLEET_ROOT, opts = {}) {
  const fleetPath = path.join(root, 'fleet.json');
  const fleet = readJson(fleetPath);
  const dir = path.join(root, 'services');
  const services = {};
  const unmanaged = [];
  for (const name of fs.readdirSync(dir).sort()) {
    if (!name.endsWith('.json')) continue;
    const spec = readJson(path.join(dir, name));
    const configPath = path.join('services', name);
    if (spec.id === '_unmanaged') {
      for (const e of spec.entries || []) {
        unmanaged.push({ ...e, managed: false, configPath });
      }
      continue;
    }
    const central = fleet.services?.[spec.id] || {};
    services[spec.id] = {
      ...spec,
      configPath,
      min: central.min ?? 0,
      max: central.max ?? 1,
      keepFloor: central.keepFloor !== false,
      enabled: central.enabled !== false,
      managed: central.managed === false ? false : spec.managed !== false,
    };
  }
  const overlay =
    opts.overlay === false ? null : path.join(root, 'data', 'runtime', 'machines-overlay.json');
  const machines = loadMachines(root, overlay);
  return {
    root,
    fleetPath: path.relative(root, fleetPath) || 'fleet.json',
    machinesPath: 'machines.json',
    machinesOverlay: overlay,
    control: fleet.control,
    nats: fleet.nats,
    machines,
    services,
    unmanaged,
  };
}

export function listServices(loaded) {
  const rows = Object.values(loaded.services).map((s) => ({
    id: s.id,
    title: s.title,
    kind: s.kind,
    managed: s.managed,
    enabled: s.enabled,
    min: s.min,
    max: s.max,
    keepFloor: s.keepFloor,
    configPath: s.configPath,
    package: s.package,
    runtime: s.runtime,
  }));
  for (const u of loaded.unmanaged) {
    rows.push({
      id: u.id,
      title: u.id,
      kind: 'unmanaged',
      managed: false,
      enabled: false,
      min: 0,
      max: 0,
      keepFloor: false,
      configPath: u.configPath,
      package: u.package,
      runtime: u.runtime,
    });
  }
  return rows;
}