import { ArrowDown, ArrowRight, ArrowUp, TrendingUp } from "lucide-react";
import { useMemo } from "react";
import { useInflation, useMonthlyLast } from "@/lib/queries";

type MonthKey = string;

type CurrencyValues = {
  variation: number | null;
  prev: number | null;
  current: number | null;
};

type MonthRow = {
  month: MonthKey;
  label: string;
  BELO: CurrencyValues;
  BLUE: CurrencyValues;
  BNA: CurrencyValues;
  inflation: number | null;
};

const MONTH_NAMES = [
  "Enero",
  "Febrero",
  "Marzo",
  "Abril",
  "Mayo",
  "Junio",
  "Julio",
  "Agosto",
  "Septiembre",
  "Octubre",
  "Noviembre",
  "Diciembre",
];

function formatMonth(monthKey: string): string {
  const [y, m] = monthKey.split("-");
  return `${MONTH_NAMES[Number(m) - 1]} ${y}`;
}

function formatPct(value: number): string {
  const sign = value >= 0 ? "+" : "";
  return `${sign}${value.toFixed(1)}%`;
}

const priceFormatter = new Intl.NumberFormat("es-AR", {
  minimumFractionDigits: 0,
  maximumFractionDigits: 0,
});

function formatPrice(value: number): string {
  return `$${priceFormatter.format(value)}`;
}

function VariationIndicator({
  variation,
  inflation,
  prev,
  current,
}: {
  variation: number | null;
  inflation: number | null;
  prev: number | null;
  current: number | null;
}) {
  if (variation === null) {
    return (
      <span className="text-xs text-muted-foreground inline-flex items-center gap-1">
        <ArrowRight className="size-3" />
        --
      </span>
    );
  }

  const indicator = (
    <span
      className={`text-xs font-medium inline-flex items-center gap-1 tabular-nums ${
        inflation !== null
          ? variation > inflation
            ? "bg-emerald-100 text-emerald-700 dark:bg-emerald-900/30 dark:text-emerald-400 px-1.5 py-0.5 rounded"
            : "bg-red-100 text-red-700 dark:bg-red-900/30 dark:text-red-400 px-1.5 py-0.5 rounded"
          : variation >= 0
            ? "text-emerald-500"
            : "text-red-500"
      }`}
    >
      {variation >= 0 ? (
        <ArrowUp className="size-3" />
      ) : (
        <ArrowDown className="size-3" />
      )}
      {formatPct(variation)}
    </span>
  );

  if (prev !== null && current !== null) {
    return (
      <span className="inline-flex items-center gap-1.5">
        {indicator}
        <span className="text-[10px] text-muted-foreground tabular-nums">
          {formatPrice(prev)} → {formatPrice(current)}
        </span>
      </span>
    );
  }

  return indicator;
}

export function MonthlyVariationTable() {
  const { data: monthlyData, isLoading: monthlyLoading } = useMonthlyLast();
  const { data: inflationData, isLoading: inflationLoading } = useInflation();

  const rows = useMemo<MonthRow[]>(() => {
    if (!monthlyData || monthlyData.length === 0) return [];

    const monthsMap = new Map<
      MonthKey,
      { BELO: number | null; BLUE: number | null; BNA: number | null }
    >();

    for (const entry of monthlyData) {
      const existing = monthsMap.get(entry.month) ?? {
        BELO: null,
        BLUE: null,
        BNA: null,
      };
      if (entry.type === "BELO") existing.BELO = entry.buy;
      if (entry.type === "BLUE") existing.BLUE = entry.buy;
      if (entry.type === "BNA") existing.BNA = entry.buy;
      monthsMap.set(entry.month, existing);
    }

    const inflationMap = new Map<MonthKey, number>();
    if (inflationData) {
      for (const inf of inflationData) {
        const monthKey = inf.fecha.slice(0, 7);
        inflationMap.set(monthKey, inf.valor);
      }
    }

    const sortedMonths = [...monthsMap.keys()].sort();

    const calcVariation = (
      currentVal: number | null,
      prevVal: number | null,
    ): number | null => {
      if (currentVal === null || prevVal === null || prevVal === 0) return null;
      return ((currentVal - prevVal) / prevVal) * 100;
    };

    return sortedMonths
      .map((month, i) => {
        const prev = i > 0 ? sortedMonths[i - 1] : null;
        const current = monthsMap.get(month);
        const prevData = prev ? monthsMap.get(prev) : null;

        const beloVar = calcVariation(
          current?.BELO ?? null,
          prevData?.BELO ?? null,
        );
        const blueVar = calcVariation(
          current?.BLUE ?? null,
          prevData?.BLUE ?? null,
        );
        const bnaVar = calcVariation(
          current?.BNA ?? null,
          prevData?.BNA ?? null,
        );

        let inflation: number | null = null;
        inflation = inflationMap.get(month) ?? null;

        return {
          month,
          label: formatMonth(month),
          BELO: {
            variation: beloVar,
            prev: prevData?.BELO ?? null,
            current: current?.BELO ?? null,
          },
          BLUE: {
            variation: blueVar,
            prev: prevData?.BLUE ?? null,
            current: current?.BLUE ?? null,
          },
          BNA: {
            variation: bnaVar,
            prev: prevData?.BNA ?? null,
            current: current?.BNA ?? null,
          },
          inflation,
        };
      })
      .reverse();
  }, [monthlyData, inflationData]);

  const isLoading = monthlyLoading || inflationLoading;

  if (isLoading) {
    return (
      <div className="flex items-center justify-center h-32 text-muted-foreground text-sm">
        Cargando datos mensuales...
      </div>
    );
  }

  if (rows.length === 0) {
    return (
      <div className="flex items-center justify-center h-32 text-muted-foreground text-sm">
        Sin datos mensuales disponibles
      </div>
    );
  }

  return (
    <>
      <div className="space-y-2 sm:hidden">
        {rows.map((row) => (
          <div
            key={row.month}
            className="rounded-lg border bg-card p-3 text-sm"
          >
            <div className="flex items-center justify-between mb-2">
              <span className="font-medium">{row.label}</span>
              {row.inflation !== null ? (
                <span className="text-xs text-muted-foreground tabular-nums inline-flex items-center gap-1">
                  <TrendingUp className="size-3" />
                  {formatPct(row.inflation)} inflación
                </span>
              ) : (
                <span className="text-xs text-muted-foreground">
                  Sin inflación
                </span>
              )}
            </div>
            <div className="grid grid-cols-3 gap-2">
              <div>
                <p className="text-[10px] text-muted-foreground mb-0.5">BELO</p>
                <VariationIndicator
                  variation={row.BELO.variation}
                  inflation={row.inflation}
                  prev={row.BELO.prev}
                  current={row.BELO.current}
                />
              </div>
              <div>
                <p className="text-[10px] text-muted-foreground mb-0.5">Blue</p>
                <VariationIndicator
                  variation={row.BLUE.variation}
                  inflation={row.inflation}
                  prev={row.BLUE.prev}
                  current={row.BLUE.current}
                />
              </div>
              <div>
                <p className="text-[10px] text-muted-foreground mb-0.5">
                  Oficial
                </p>
                <VariationIndicator
                  variation={row.BNA.variation}
                  inflation={row.inflation}
                  prev={row.BNA.prev}
                  current={row.BNA.current}
                />
              </div>
            </div>
          </div>
        ))}
      </div>

      <div className="hidden overflow-x-auto rounded-lg border sm:block">
        <table className="w-full text-sm">
          <thead>
            <tr className="border-b bg-muted/50">
              <th className="px-3 py-2 text-left text-xs font-medium text-muted-foreground">
                Mes
              </th>
              <th className="px-3 py-2 text-right text-xs font-medium text-muted-foreground">
                BELO
              </th>
              <th className="px-3 py-2 text-right text-xs font-medium text-muted-foreground">
                Blue
              </th>
              <th className="px-3 py-2 text-right text-xs font-medium text-muted-foreground">
                Oficial
              </th>
              <th className="px-3 py-2 text-right text-xs font-medium text-muted-foreground">
                Inflación
              </th>
            </tr>
          </thead>
          <tbody>
            {rows.map((row) => (
              <tr
                key={row.month}
                className="border-b last:border-0 hover:bg-muted/30"
              >
                <td className="px-3 py-2.5 font-medium">{row.label}</td>
                <td className="px-3 py-2.5 text-right">
                  <VariationIndicator
                    variation={row.BELO.variation}
                    inflation={row.inflation}
                    prev={row.BELO.prev}
                    current={row.BELO.current}
                  />
                </td>
                <td className="px-3 py-2.5 text-right">
                  <VariationIndicator
                    variation={row.BLUE.variation}
                    inflation={row.inflation}
                    prev={row.BLUE.prev}
                    current={row.BLUE.current}
                  />
                </td>
                <td className="px-3 py-2.5 text-right">
                  <VariationIndicator
                    variation={row.BNA.variation}
                    inflation={row.inflation}
                    prev={row.BNA.prev}
                    current={row.BNA.current}
                  />
                </td>
                <td className="px-3 py-2.5 text-right">
                  {row.inflation !== null ? (
                    <span className="text-xs text-muted-foreground tabular-nums">
                      {formatPct(row.inflation)}
                    </span>
                  ) : (
                    <span className="text-xs text-muted-foreground">--</span>
                  )}
                </td>
              </tr>
            ))}
          </tbody>
        </table>
      </div>
    </>
  );
}