import { type IndicatorData } from "../../types";
import { calculateSMA, calculateEMA, calculateRSI, calculateMACD, calculateBollingerBands, calculateATR, calculateVolumeAvg } from "../../utils/indicators";
import alpacaService from "../../lib/alpacaClient";

async function fetchHistoricPrices(symbol: string): Promise<number[]> {
  try {
    const bars = await alpacaService.fetchBars(symbol, "1Day", { limit: 60 });
    return bars.map((b: any) => {
      const c = b.ClosePrice ?? b.c ?? 0;
      return typeof c === "number" ? c : 0;
    }).filter((p: number) => p > 0);
  } catch (e) {
    console.error(`Failed to fetch bars for ${symbol}:`, e);
    return [];
  }
}

async function fetchVolumes(symbol: string): Promise<number[]> {
  try {
    const bars = await alpacaService.fetchBars(symbol, "1Day", { limit: 60 });
    return bars.map((b: any) => {
      const v = b.Volume ?? b.v ?? 0;
      return typeof v === "number" ? v : 0;
    }).filter((v: number) => v > 0);
  } catch (e) {
    return [];
  }
}

async function fetchHighLow(symbol: string): Promise<{ highs: number[]; lows: number[] }> {
  try {
    const bars = await alpacaService.fetchBars(symbol, "1Day", { limit: 60 });
    const highs: number[] = [];
    const lows: number[] = [];
    for (const b of bars) {
      const h = b.HighPrice ?? b.h ?? 0;
      const l = b.LowPrice ?? b.l ?? 0;
      if (typeof h === "number" && h > 0) highs.push(h);
      if (typeof l === "number" && l > 0) lows.push(l);
    }
    return { highs, lows };
  } catch (e) {
    return { highs: [], lows: [] };
  }
}

export async function loader({ request }: { request: Request }) {
  const url = new URL(request.url);
  const symbol = url.searchParams.get("symbol");

  if (!symbol) {
    return Response.json({ error: "Symbol is required" }, { status: 400 });
  }

  try {
    const prices = await fetchHistoricPrices(symbol.toUpperCase());
    if (prices.length < 26) {
      return Response.json({ error: "Insufficient price data" }, { status: 404 });
    }

    const volumes = await fetchVolumes(symbol.toUpperCase());
    const { highs, lows } = await fetchHighLow(symbol.toUpperCase());

    const sma20 = calculateSMA(prices, 20);
    const sma50 = prices.length >= 50 ? calculateSMA(prices, 50) : 0;
    const ema12 = calculateEMA(prices, 12);
    const ema26 = calculateEMA(prices, 26);
    const rsi14 = calculateRSI(prices, 14);
    const macd = calculateMACD(prices);
    const bb = calculateBollingerBands(prices, 20);
    const atr = highs.length > 0 && lows.length > 0 ? calculateATR(highs, lows, prices, 14) : 0;
    const avgVol = volumes.length > 0 ? calculateVolumeAvg(volumes, 20) : 0;

    const data: IndicatorData = {
      symbol: symbol.toUpperCase(),
      indicators: {
        sma: sma20,
        sma50,
        ema12,
        ema26,
        rsi: rsi14,
        macd: macd.histogram,
        bbUpper: bb.upper,
        bbLower: bb.lower,
        bbMiddle: bb.middle,
        atr,
        avgVolume: avgVol,
      },
    };
    return Response.json(data);
  } catch (error) {
    console.error("Indicators error:", error);
    return Response.json({ error: "Failed to fetch indicators" }, { status: 500 });
  }
}