import { config as loadEnv } from 'dotenv'

loadEnv()

function optional(name: string): string | undefined {
  const value = process.env[name]?.trim()
  return value ? value : undefined
}

function optionalNumber(name: string): number | undefined {
  const raw = optional(name)
  if (raw === undefined) return undefined
  const value = Number(raw)
  if (!Number.isFinite(value)) throw new Error(`${name} must be a number, got "${raw}"`)
  return value
}

/**
 * amoCRM settings. Deliberately not throwing when they are missing: the site
 * must still boot and serve pages without a CRM connection — only the lead
 * endpoint degrades, and it says so explicitly.
 */
export interface AmoConfig {
  baseUrl: string
  token: string
  pipelineId: number
  responsibleUserId?: number
  tags: string[]
}

export function readAmoConfig(): AmoConfig | null {
  const subdomain = optional('AMO_SUBDOMAIN')
  const token = optional('AMO_LONG_LIVED_TOKEN')
  if (!subdomain || !token) return null

  // Accepts "exotherapy", "exotherapy.amocrm.ru", or a full URL (an explicit
  // scheme is kept as-is, which is what local mocks and self-hosted setups need).
  const host = subdomain.replace(/\/+$/, '')
  const baseUrl = /^https?:\/\//.test(host)
    ? host
    : `https://${host.includes('.') ? host : `${host}.${optional('AMO_DOMAIN') ?? 'amocrm.ru'}`}`

  return {
    baseUrl,
    token,
    pipelineId: optionalNumber('AMO_PIPELINE_ID') ?? 10980758,
    responsibleUserId: optionalNumber('AMO_RESPONSIBLE_USER_ID'),
    tags: (optional('AMO_LEAD_TAGS') ?? '')
      .split(',')
      .map((t) => t.trim())
      .filter(Boolean),
  }
}

export const serverConfig = {
  port: optionalNumber('PORT') ?? 3000,
  isProduction: process.env.NODE_ENV === 'production',
}