Function processEvents

src/lib/polymarket.ts:101–202

(events: PolymarketEvent[])

const previousPrices = new Map<string, number>();

export function processEvents(events: PolymarketEvent[]): {
  mapped: ProcessedMarket[];
  unmapped: ProcessedMarket[];
} {
  const mapped: ProcessedMarket[] = [];
  const unmapped: ProcessedMarket[] = [];

  for (const event of events) {
    const vol = parseFloat(String(event.volume || event.volume_num || 0));
    if (vol < 500) continue;

    const category = detectCategory(event);

    const markets = event.markets || [];

    // Find the highest-probability sub-market (not just the first one)
    let primary = markets[0];
    let prob: number | null = null;
    for (const mk of markets) {
      try {
        const raw = mk.outcomePrices;
        if (!raw) continue;
        const p = Array.isArray(raw) ? raw : JSON.parse(raw as string);
        const val = parseFloat(p[0]);
        if (!isNaN(val) && (prob === null || val > prob)) {
          prob = val;
          primary = mk;
        }
      } catch {
        // Skip malformed outcomePrices
      }
    }

    // Fallback to event-level prices if no sub-market had valid prices
    if (prob === null) {
      try {
        const prices = (event as unknown as Record<string, unknown>).outcomePrices;
        if (prices) {
          const p = Array.isArray(prices) ? prices : JSON.parse(prices as string);
          prob = parseFloat(p[0]);
        }
      } catch {
        // Skip malformed outcomePrices
      }
    }

    const marketId = primary?.id || event.id;
    let change: number | null = null;
    if (primary?.oneDayPriceChange !== undefined) {
      change = parseFloat(String(primary.oneDayPriceChange));
    } else if (event.oneDayPriceChange !== undefined) {
      change = parseFloat(String(event.oneDayPriceChange));
    }

    let recentChange: number | null = null;
    if (prob !== null && previousPrices.has(marketId)) {
      recentChange = prob - previousPrices.get(marketId)!;
    }