/**
 * Telegram — the real L6 "Comms" layer, in ~60 lines via the raw Bot API (no
 * dependency). Outbound: tgSend() broadcasts signals/closes. Inbound: tgPoll()
 * long-polls getUpdates for slash commands (/status, /pnl, /positions, /help).
 *
 * If no token/chat is configured the worker still runs — messages print to stdout
 * so you can demo the whole loop with zero Telegram setup.
 */
import { CONFIG } from './config.ts'

const api = (method: string) => `https://api.telegram.org/bot${CONFIG.tgToken}/${method}`

export const TG_ENABLED = Boolean(CONFIG.tgToken && CONFIG.tgChat)

const stripHtml = (s: string) => s.replace(/<[^>]+>/g, '')

/** Send a message (HTML). Defaults to the configured chat; pass chatId to reply. */
export async function tgSend(text: string, chatId: string | number = CONFIG.tgChat): Promise<void> {
  if (!CONFIG.tgToken || !chatId) {
    console.log('\n' + stripHtml(text) + '\n')
    return
  }
  try {
    const res = await fetch(api('sendMessage'), {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        chat_id: chatId,
        text,
        parse_mode: 'HTML',
        disable_web_page_preview: true,
      }),
    })
    if (!res.ok) console.error('[tg] send failed', res.status, await res.text())
  } catch (e) {
    console.error('[tg] send error', (e as Error).message)
  }
}

let offset = 0

/** Poll once for new commands and dispatch them. Cheap to call on an interval. */
export async function tgPoll(
  handler: (cmd: string, chatId: number) => Promise<void>,
): Promise<void> {
  if (!CONFIG.tgToken) return
  try {
    const res = await fetch(api('getUpdates') + `?timeout=0&offset=${offset}`)
    if (!res.ok) return
    const json = (await res.json()) as {
      result?: { update_id: number; message?: { text?: string; chat?: { id: number } } }[]
    }
    for (const u of json.result ?? []) {
      offset = u.update_id + 1
      const text = u.message?.text
      const chatId = u.message?.chat?.id
      if (text && chatId != null && text.startsWith('/')) {
        // strip @BotName suffix and arguments → bare command
        const cmd = text.trim().split(/\s+/)[0].split('@')[0].toLowerCase()
        await handler(cmd, chatId)
      }
    }
  } catch {
    /* transient — ignore, next poll retries */
  }
}