chore: initial import

apps/visualizer/src/lib/api.ts

@@ -0,0 +1,76 @@
+export type Candle = {
+  time: number; // unix seconds
+  open: number;
+  high: number;
+  low: number;
+  close: number;
+  volume?: number;
+  oracle?: number | null;
+};
+
+export type SeriesPoint = {
+  time: number; // unix seconds
+  value: number | null;
+};
+
+export type ChartIndicators = {
+  oracle?: SeriesPoint[];
+  sma20?: SeriesPoint[];
+  ema20?: SeriesPoint[];
+  bb20?: { upper: SeriesPoint[]; lower: SeriesPoint[]; mid: SeriesPoint[] };
+  rsi14?: SeriesPoint[];
+  macd?: { macd: SeriesPoint[]; signal: SeriesPoint[] };
+};
+
+export type ChartResponse = {
+  ok: boolean;
+  symbol?: string;
+  source?: string | null;
+  tf?: string;
+  bucketSeconds?: number;
+  candles?: Candle[];
+  indicators?: ChartIndicators;
+  error?: string;
+};
+
+function getApiBaseUrl(): string {
+  const v = (import.meta as any).env?.VITE_API_URL;
+  if (v) return String(v);
+  return '/api';
+}
+
+export async function fetchChart(params: {
+  symbol: string;
+  source?: string;
+  tf: string;
+  limit: number;
+}): Promise<{ candles: Candle[]; indicators: ChartIndicators; meta: { tf: string; bucketSeconds: number } }> {
+  const base = getApiBaseUrl();
+  const u = new URL(base, window.location.origin);
+  u.pathname = u.pathname && u.pathname !== '/' ? u.pathname.replace(/\/$/, '') + '/v1/chart' : '/v1/chart';
+  u.searchParams.set('symbol', params.symbol);
+  u.searchParams.set('tf', params.tf);
+  u.searchParams.set('limit', String(params.limit));
+  if (params.source && params.source.trim()) u.searchParams.set('source', params.source.trim());
+
+  const res = await fetch(u.toString());
+  const text = await res.text();
+  if (!res.ok) throw new Error(`API HTTP ${res.status}: ${text}`);
+  const json = JSON.parse(text) as ChartResponse;
+  if (!json.ok) throw new Error(json.error || 'API: error');
+  return {
+    candles: (json.candles || []).map((c) => ({
+      ...c,
+      time: Number(c.time),
+      open: Number(c.open),
+      high: Number(c.high),
+      low: Number(c.low),
+      close: Number(c.close),
+      volume: c.volume == null ? undefined : Number(c.volume),
+      oracle: c.oracle == null ? null : Number(c.oracle),
+    })),
+    indicators: json.indicators || {},
+    meta: { tf: String(json.tf || params.tf), bucketSeconds: Number(json.bucketSeconds || 0) },
+  };
+}
+