// modules/data/bitcoin.js — Bitcoin block height polling
import { state } from '../core/state.js';

const blockHeightDisplay = document.getElementById('block-height-display');
const blockHeightValue = document.getElementById('block-height-value');

export async function fetchBlockHeight() {
  try {
    const res = await fetch('https://blockstream.info/api/blocks/tip/height');
    if (!res.ok) return;
    const height = parseInt(await res.text(), 10);
    if (isNaN(height)) return;

    if (state.lastBlockHeight !== 0 && height !== state.lastBlockHeight) {
      if (blockHeightDisplay) {
        blockHeightDisplay.classList.remove('fresh');
        void blockHeightDisplay.offsetWidth;
        blockHeightDisplay.classList.add('fresh');
      }
      state.starPulseIntensity = 1.0;
    }

    state.lastBlockHeight = height;
    state.blockHeight = height;
    if (blockHeightValue) blockHeightValue.textContent = height.toLocaleString();
  } catch (_) {
    // Network unavailable — keep last known value
  }
}

export function startBlockPolling() {
  fetchBlockHeight();
  setInterval(fetchBlockHeight, 60000);
}