// Configuration management for OGraph CLI
import { readFile, writeFile, mkdir } from 'node:fs/promises'
import { existsSync } from 'node:fs'
import { join } from 'node:path'
import { homedir } from 'node:os'

// ─── Types ─────────────────────────────────────────────────────────────────────

export interface Config {
  endpoint?: string
  token?: string
}

// ─── Paths ─────────────────────────────────────────────────────────────────────

function getConfigDir(): string {
  return process.env.OGRAPH_CONFIG_DIR || join(homedir(), '.config', 'ograph')
}

function getConfigPath(): string {
  return join(getConfigDir(), 'config.json')
}

// ─── Config Functions ──────────────────────────────────────────────────────────

export async function loadConfig(): Promise<Config> {
  const CONFIG_PATH = getConfigPath()
  if (!existsSync(CONFIG_PATH)) {
    return {}
  }

  try {
    const data = await readFile(CONFIG_PATH, 'utf-8')
    return JSON.parse(data)
  } catch (error) {
    console.warn('Warning: config.json is malformed, using empty config')
    return {}
  }
}

export async function saveConfig(config: Config): Promise<void> {
  const CONFIG_DIR = getConfigDir()
  const CONFIG_PATH = getConfigPath()
  try {
    // Ensure config directory exists
    if (!existsSync(CONFIG_DIR)) {
      await mkdir(CONFIG_DIR, { recursive: true })
    }

    await writeFile(CONFIG_PATH, JSON.stringify(config, null, 2), 'utf-8')
  } catch (error) {
    throw new Error(`Failed to save config: ${error}`)
  }
}

export async function setConfigValue(key: keyof Config, value: string): Promise<void> {
  const config = await loadConfig()
  config[key] = value
  await saveConfig(config)
}

export async function getConfigValue(key: keyof Config): Promise<string | undefined> {
  const config = await loadConfig()
  return config[key]
}