import { motion, useReducedMotion } from "framer-motion";
import Box from "@mui/material/Box";
import Typography from "@mui/material/Typography";
import { StatCard, type StatCardColor } from "../../ui";
import { formatCurrency } from "../../utils/formatters";

interface KpiCard {
  label: string;
  value: string;
  sub?: string;
  color: string;
  footer: string | null;
}

interface RevenueItem {
  amount: number;
  currency: string;
}

interface InvoicesData {
  revenue_this_month: RevenueItem[];
  revenue_czk?: number | null;
  unpaid_count: number;
}

interface DashData {
  attendance?: {
    present_today: number;
    total_active: number;
    on_leave: number;
  };
  offers?: {
    open_count: number;
    created_this_month: number;
  };
  invoices?: InvoicesData;
  leave_pending?: {
    count: number;
  };
}

interface DashKpiCardsProps {
  dashData: DashData | null;
}

function buildKpiCards(dashData: DashData | null): KpiCard[] {
  const cards: KpiCard[] = [];
  if (dashData?.attendance) {
    cards.push({
      label: "Přítomní dnes",
      value: `${dashData.attendance.present_today}`,
      sub: `/ ${dashData.attendance.total_active}`,
      color: "success",
      footer:
        dashData.attendance.on_leave > 0
          ? `${dashData.attendance.on_leave} nepřítomných`
          : null,
    });
  }
  if (dashData?.offers) {
    cards.push({
      label: "Otevřené nabídky",
      value: `${dashData.offers.open_count}`,
      color: "info",
      footer:
        dashData.offers.created_this_month > 0
          ? `${dashData.offers.created_this_month} tento měsíc`
          : null,
    });
  }
  if (dashData?.invoices) {
    cards.push(buildInvoiceKpi(dashData.invoices));
  }
  if (dashData?.leave_pending) {
    cards.push({
      label: "Žádosti o volno",
      value: `${dashData.leave_pending.count}`,
      color: "danger",
      footer: dashData.leave_pending.count > 0 ? "čeká na schválení" : null,
    });
  }
  return cards;
}

function buildInvoiceKpi(invoices: InvoicesData): KpiCard {
  const rev = invoices.revenue_this_month || [];
  const hasForeign = rev.some((r) => r.currency !== "CZK");
  const hasCzkTotal =
    hasForeign &&
    invoices.revenue_czk !== null &&
    invoices.revenue_czk !== undefined;
  const fallbackText =
    rev.length > 0
      ? rev.map((r) => formatCurrency(r.amount, r.currency)).join(" · ")
      : "0 Kč";
  const revenueText = hasCzkTotal
    ? formatCurrency(invoices.revenue_czk!, "CZK")
    : fallbackText;
  const detailText =
    hasForeign && rev.length > 0
      ? rev.map((r) => formatCurrency(r.amount, r.currency)).join(" · ")
      : null;
  const unpaidText =
    invoices.unpaid_count > 0 ? `${invoices.unpaid_count} neuhrazených` : null;
  const footerParts = [detailText, unpaidText].filter(Boolean);
  return {
    label: "Tržby (měsíc)",
    value: revenueText,
    color: "warning",
    footer: footerParts.length > 0 ? footerParts.join(" · ") : null,
  };
}

// Maps the legacy KPI color tokens to the StatCard color palette
// (danger → error; the rest are 1:1).
const KPI_COLOR_MAP: Record<string, StatCardColor> = {
  success: "success",
  info: "info",
  warning: "warning",
  danger: "error",
};

export default function DashKpiCards({ dashData }: DashKpiCardsProps) {
  const reduce = useReducedMotion();
  const kpiCards = buildKpiCards(dashData);
  if (kpiCards.length === 0) {
    return null;
  }

  return (
    <Box
      component={motion.div}
      initial={reduce ? false : { opacity: 0, y: 12 }}
      animate={reduce ? undefined : { opacity: 1, y: 0 }}
      transition={{ duration: 0.25, delay: 0.06 }}
      sx={{
        display: "grid",
        gridTemplateColumns: {
          xs: "1fr",
          sm: "repeat(2, 1fr)",
          lg: `repeat(${Math.min(kpiCards.length, 4)}, 1fr)`,
        },
        gap: 2,
        mb: 3,
      }}
    >
      {kpiCards.map((kpi) => (
        <StatCard
          key={kpi.label}
          color={KPI_COLOR_MAP[kpi.color] ?? "default"}
          label={kpi.label}
          value={
            <>
              {kpi.value}
              {kpi.sub && (
                <Typography
                  component="span"
                  color="text.secondary"
                  sx={{
                    fontSize: "0.75em",
                    fontWeight: 500,
                    ml: 0.5,
                    fontFamily: "inherit",
                  }}
                >
                  {kpi.sub}
                </Typography>
              )}
            </>
          }
          footer={kpi.footer ?? undefined}
        />
      ))}
    </Box>
  );
}
