import { useState } from "react";
import { useQuery } from "@tanstack/react-query";
import {
  AreaChart,
  Area,
  XAxis,
  YAxis,
  Tooltip,
  ResponsiveContainer,
  PieChart,
  Pie,
  Cell,
  CartesianGrid,
} from "recharts";
import {
  DollarSign,
  CalendarCheck,
  TrendingUp,
  TrendingDown,
  Crown,
  Star,
  Scissors,
  Ticket as TicketIcon,
  Flame,
  Trophy,
  Coins,
  Wallet,
} from "lucide-react";
import { api } from "../lib/api";
import { useAuth } from "../lib/auth";
import { PageHeader, Avatar, Spinner, EmptyState } from "../components/ui";
import {
  formatCurrency,
  formatNumber,
  formatDate,
  paymentLabel,
  cn,
} from "../lib/format";

const RANGES = [
  { value: "7", label: "7 días" },
  { value: "30", label: "30 días" },
  { value: "60", label: "60 días" },
];

const PIE_COLORS = ["#3b66ff", "#f17616", "#10b981", "#a855f7", "#ec4899", "#14b8a6", "#f59e0b", "#6366f1"];

export function DashboardPage() {
  const { business } = useAuth();
  const [range, setRange] = useState("30");
  const symbol = business?.currency_symbol ?? "$";

  const { data: overview, isLoading: ovLoading } = useQuery({
    queryKey: ["dashboard", "overview", range],
    queryFn: () => api.dashboard.overview(Number(range)),
  });
  const { data: emp } = useQuery({
    queryKey: ["dashboard", "best-employees", range],
    queryFn: () => api.dashboard.bestEmployees(range),
  });
  const { data: svc } = useQuery({
    queryKey: ["dashboard", "best-services", range],
    queryFn: () => api.dashboard.bestServices(range),
  });
  const { data: tickets } = useQuery({
    queryKey: ["dashboard", "top-tickets", range],
    queryFn: () => api.dashboard.topTickets(range, 6),
  });
  const { data: topClients } = useQuery({
    queryKey: ["dashboard", "top-clients", range],
    queryFn: () => api.dashboard.topClients(range, 6),
  });
  const { data: freqClients } = useQuery({
    queryKey: ["dashboard", "frequent-clients", range],
    queryFn: () => api.dashboard.frequentClients(range, 6),
  });
  const { data: trend } = useQuery({
    queryKey: ["dashboard", "trend", range],
    queryFn: () => api.dashboard.revenueTrend(Number(range)),
  });
  const { data: cats } = useQuery({
    queryKey: ["dashboard", "categories", range],
    queryFn: () => api.dashboard.revenueByCategory(range),
  });
  const { data: commissions } = useQuery({
    queryKey: ["dashboard", "commissions", range],
    queryFn: () => api.dashboard.commissions(range),
  });

  const trendData = (trend?.points ?? []).map((p) => ({
    ...p,
    label: new Date(p.date).toLocaleDateString("es-MX", { day: "numeric", month: range === "7" ? "short" : undefined }),
  }));

  const totalCat = (cats?.slices ?? []).reduce((a, s) => a + s.revenue, 0) || 1;

  return (
    <div className="flex h-full flex-col">
      <PageHeader
        title="Tablero"
        subtitle={`Rendimiento de ${business?.name ?? "tu negocio"}`}
        actions={
          <div className="flex items-center gap-1 rounded-xl border border-slate-200 bg-white p-1">
            {RANGES.map((r) => (
              <button
                key={r.value}
                onClick={() => setRange(r.value)}
                className={cn(
                  "tap-target rounded-lg px-3 py-1.5 text-xs font-semibold transition-colors",
                  range === r.value ? "bg-brand-500 text-white" : "text-slate-600 hover:bg-slate-100"
                )}
              >
                {r.label}
              </button>
            ))}
          </div>
        }
      />

      <div className="flex-1 space-y-5 px-5 py-5 sm:px-7">
        {/* KPIs */}
        <div className="grid grid-cols-1 gap-3 sm:grid-cols-2 xl:grid-cols-5">
          <KpiCard
            title="Ingresos de hoy"
            value={ovLoading ? "…" : formatCurrency(overview?.revenue_today ?? 0, symbol)}
            sub="día de hoy"
            icon={Wallet}
            color="#10b981"
          />
          <KpiCard
            title="Ingresos del período"
            value={ovLoading ? "…" : formatCurrency(overview?.revenue_range ?? 0, symbol)}
            sub={`últimos ${range} días`}
            delta={overview?.revenue_change_pct}
            deltaSuffix="% vs período anterior"
            icon={DollarSign}
            color="#3b66ff"
          />
          <KpiCard
            title="Citas programadas"
            value={ovLoading ? "…" : formatNumber(overview?.appts_upcoming ?? 0)}
            sub="próximas"
            icon={CalendarCheck}
            color="#6366f1"
          />
          <KpiCard
            title="Ticket promedio"
            value={ovLoading ? "…" : formatCurrency(overview?.avg_ticket ?? 0, symbol)}
            sub="por venta"
            icon={TrendingUp}
            color="#a855f7"
          />
          <KpiCard
            title="Finalización"
            value={ovLoading ? "…" : `${overview?.completion_pct ?? 0}%`}
            sub={`${overview?.cancel_rate ?? 0}% cancelación`}
            icon={Flame}
            color="#f17616"
          />
        </div>

        {/* Revenue chart + Category pie */}
        <div className="grid grid-cols-1 gap-5 lg:grid-cols-3">
          <div className="card p-5 lg:col-span-2">
            <div className="mb-4 flex items-center justify-between">
              <div>
                <h3 className="text-sm font-bold text-slate-900">Ingresos del período</h3>
                <p className="text-xs text-slate-500">Tendencia diaria</p>
              </div>
              <div className="flex items-center gap-1.5 text-xs font-bold text-brand-600">
                <div className="h-2 w-2 rounded-full bg-brand-500" />
                Ingresos
              </div>
            </div>
            {!trend ? (
              <div className="flex h-64 items-center justify-center"><Spinner /></div>
            ) : (
              <ResponsiveContainer width="100%" height={260}>
                <AreaChart data={trendData} margin={{ left: -10, right: 8, top: 4 }}>
                  <defs>
                    <linearGradient id="rev" x1="0" y1="0" x2="0" y2="1">
                      <stop offset="0%" stopColor="#3b66ff" stopOpacity={0.35} />
                      <stop offset="100%" stopColor="#3b66ff" stopOpacity={0} />
                    </linearGradient>
                  </defs>
                  <CartesianGrid stroke="#eef0f4" vertical={false} />
                  <XAxis dataKey="label" tick={{ fontSize: 11, fill: "#94a3b8" }} axisLine={false} tickLine={false} />
                  <YAxis
                    tick={{ fontSize: 11, fill: "#94a3b8" }}
                    axisLine={false}
                    tickLine={false}
                    tickFormatter={(v) => `${symbol}${v >= 1000 ? `${(v / 1000).toFixed(0)}k` : v}`}
                  />
                  <Tooltip
                    contentStyle={{
                      borderRadius: 12,
                      border: "1px solid #eef0f4",
                      boxShadow: "0 8px 24px -8px rgba(0,0,0,0.15)",
                      fontSize: 12,
                    }}
                    formatter={(v: any) => [formatCurrency(Number(v), symbol), "Ingresos"]}
                    labelStyle={{ fontWeight: 700, color: "#0f172a" }}
                  />
                  <Area type="monotone" dataKey="revenue" stroke="#3b66ff" strokeWidth={2.5} fill="url(#rev)" />
                </AreaChart>
              </ResponsiveContainer>
            )}
          </div>

          <div className="card p-5">
            <div className="mb-4">
              <h3 className="text-sm font-bold text-slate-900">Por categoría</h3>
              <p className="text-xs text-slate-500">Distribución de ingresos</p>
            </div>
            {!cats ? (
              <div className="flex h-64 items-center justify-center"><Spinner /></div>
            ) : cats.slices.length === 0 ? (
              <EmptyState title="Sin datos" />
            ) : (
              <div className="flex flex-col items-center">
                <ResponsiveContainer width="100%" height={180}>
                  <PieChart>
                    <Pie
                      data={cats.slices}
                      dataKey="revenue"
                      nameKey="category"
                      innerRadius={48}
                      outerRadius={72}
                      paddingAngle={2}
                    >
                      {cats.slices.map((_, i) => (
                        <Cell key={i} fill={PIE_COLORS[i % PIE_COLORS.length]} />
                      ))}
                    </Pie>
                    <Tooltip
                      contentStyle={{ borderRadius: 12, border: "1px solid #eef0f4", fontSize: 12 }}
                      formatter={(v: any, _n, p: any) => [
                        `${formatCurrency(Number(v), symbol)} (${Math.round((Number(v) / totalCat) * 100)}%)`,
                        p.payload.category,
                      ]}
                    />
                  </PieChart>
                </ResponsiveContainer>
                <div className="mt-2 w-full space-y-1.5">
                  {cats.slices.slice(0, 5).map((s, i) => (
                    <div key={s.category} className="flex items-center gap-2 text-xs">
                      <span className="h-2.5 w-2.5 rounded-sm" style={{ background: PIE_COLORS[i % PIE_COLORS.length] }} />
                      <span className="flex-1 font-medium text-slate-600">{s.category}</span>
                      <span className="font-bold text-slate-800">{formatCurrency(s.revenue, symbol)}</span>
                    </div>
                  ))}
                </div>
              </div>
            )}
          </div>
        </div>

        {/* Best employees + best services */}
        <div className="grid grid-cols-1 gap-5 lg:grid-cols-2">
          <RankCard
            title="Mejores empleados"
            subtitle="Por ingresos generados"
            icon={Crown}
            iconColor="#f59e0b"
            items={(emp?.employees ?? []).slice(0, 5).map((r, i) => ({
              id: r.employee.id,
              rank: i + 1,
              title: r.employee.name,
              subtitle: r.employee.role,
              value: formatCurrency(r.revenue, symbol),
              extra: `${r.appointments} citas · ⭐ ${r.avg_rating}`,
              color: r.employee.color,
            }))}
          />
          <RankCard
            title="Servicios más rentables"
            subtitle="Por ingresos generados"
            icon={Scissors}
            iconColor="#3b66ff"
            barMode
            items={(svc?.services ?? []).slice(0, 5).map((r, i) => ({
              id: r.service.id,
              rank: i + 1,
              title: r.service.name,
              subtitle: r.service.category,
              value: formatCurrency(r.revenue, symbol),
              extra: `${r.count} ventas`,
              color: r.service.color,
            }))}
          />
        </div>

        {/* Top tickets */}
        <div className="card p-5">
          <div className="mb-3 flex items-center justify-between">
            <div className="flex items-center gap-2">
              <TicketIcon className="h-4 w-4 text-accent-600" />
              <h3 className="text-sm font-bold text-slate-900">Tickets más altos</h3>
            </div>
            <span className="text-xs text-slate-500">últimos {range} días</span>
          </div>
          {!tickets ? (
            <div className="flex h-24 items-center justify-center"><Spinner /></div>
          ) : tickets.tickets.length === 0 ? (
            <EmptyState title="Sin tickets" />
          ) : (
            <>
              {/* Mobile cards */}
              <div className="divide-y divide-slate-50 sm:hidden">
                {tickets.tickets.map(({ ticket }) => (
                  <div key={ticket.id} className="flex items-center gap-2 py-2">
                    <Avatar name={ticket.client?.name ?? "?"} size={30} color="#94a3b8" />
                    <div className="min-w-0 flex-1">
                      <div className="truncate text-sm font-bold text-slate-800">{ticket.client?.name}</div>
                      <div className="flex items-center gap-1.5">
                        <span className="chip" style={{ background: `${ticket.service?.color}1a`, color: ticket.service?.color }}>
                          {ticket.service?.name}
                        </span>
                      </div>
                      <div className="text-[11px] text-slate-400">{ticket.employee?.name} · {paymentLabel(ticket.payment_method)}</div>
                    </div>
                    <div className="shrink-0 text-right font-bold text-slate-900">
                      {formatCurrency(ticket.amount + ticket.tip, symbol)}
                    </div>
                  </div>
                ))}
              </div>
              {/* Desktop table */}
              <div className="hidden overflow-x-auto sm:block">
                <table className="w-full text-sm">
                  <thead>
                    <tr className="text-left text-[11px] font-bold uppercase tracking-wider text-slate-400">
                      <th className="px-2 py-1.5">Cliente</th>
                      <th className="px-2 py-1.5">Servicio</th>
                      <th className="px-2 py-1.5">Especialista</th>
                      <th className="px-2 py-1.5">Pago</th>
                      <th className="px-2 py-1.5 text-right">Total</th>
                    </tr>
                  </thead>
                  <tbody>
                    {tickets.tickets.map(({ ticket }) => (
                      <tr key={ticket.id} className="border-t border-slate-50">
                        <td className="px-2 py-2">
                          <div className="flex items-center gap-2">
                            <Avatar name={ticket.client?.name ?? "?"} size={26} color="#94a3b8" />
                            <span className="font-semibold text-slate-800">{ticket.client?.name}</span>
                          </div>
                        </td>
                        <td className="px-2 py-2">
                          <span className="chip" style={{ background: `${ticket.service?.color}1a`, color: ticket.service?.color }}>
                            {ticket.service?.name}
                          </span>
                        </td>
                        <td className="px-2 py-2 text-slate-600">{ticket.employee?.name}</td>
                        <td className="px-2 py-2 text-xs text-slate-500">{paymentLabel(ticket.payment_method)}</td>
                        <td className="px-2 py-2 text-right font-bold text-slate-900">
                          {formatCurrency(ticket.amount + ticket.tip, symbol)}
                        </td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            </>
          )}
        </div>

        {/* Top + frequent clients */}
        <div className="grid grid-cols-1 gap-5 lg:grid-cols-2">
          <RankCard
            title="Top clientes"
            subtitle="Por gasto total"
            icon={Trophy}
            iconColor="#a855f7"
            items={(topClients?.clients ?? []).slice(0, 6).map((r, i) => ({
              id: r.client.id,
              rank: i + 1,
              title: r.client.name,
              subtitle: r.last_visit ? `Última visita ${formatDate(r.last_visit)}` : "—",
              value: formatCurrency(r.total_spent, symbol),
              extra: `${r.visits} visitas`,
              tags: r.client.tags,
            }))}
          />
          <RankCard
            title="Clientes frecuentes"
            subtitle="Por número de visitas"
            icon={Flame}
            iconColor="#f17616"
            items={(freqClients?.clients ?? []).slice(0, 6).map((r, i) => ({
              id: r.client.id,
              rank: i + 1,
              title: r.client.name,
              subtitle: r.last_visit ? `Última visita ${formatDate(r.last_visit)}` : "—",
              value: `${r.visits} visitas`,
              extra: formatCurrency(r.total_spent, symbol),
              tags: r.client.tags,
            }))}
          />
        </div>

        {/* Commissions */}
        <div className="card overflow-hidden">
          <div className="flex items-center justify-between border-b border-slate-100 px-5 py-4">
            <div className="flex items-center gap-2">
              <Coins className="h-4 w-4 text-emerald-600" />
              <h3 className="text-sm font-bold text-slate-900">Comisiones del equipo</h3>
            </div>
            <span className="text-xs text-slate-500">últimos {range} días</span>
          </div>
          {!commissions ? (
            <div className="flex h-24 items-center justify-center"><Spinner /></div>
          ) : (
            <div className="grid grid-cols-1 gap-2 p-4 sm:grid-cols-2 lg:grid-cols-3">
              <div className="rounded-xl bg-emerald-50 p-3">
                <div className="text-[10px] font-semibold uppercase tracking-wide text-emerald-700">Total comisiones</div>
                <div className="text-xl font-extrabold text-emerald-700">{formatCurrency(commissions.total, symbol)}</div>
              </div>
              {(commissions.rows ?? []).slice(0, 6).map((r: any) => (
                <div key={r.employee.id} className="flex items-center gap-2 rounded-xl bg-slate-50/70 px-3 py-2">
                  <Avatar name={r.employee.name} color={r.employee.color} size={32} />
                  <div className="min-w-0 flex-1">
                    <div className="truncate text-sm font-bold text-slate-800">{r.employee.name}</div>
                    <div className="text-[11px] text-slate-500">{r.sales} ventas · {formatCurrency(r.revenue, symbol)}</div>
                  </div>
                  <div className="text-right">
                    <div className="text-sm font-extrabold text-emerald-600">{formatCurrency(r.commission, symbol)}</div>
                    <div className="text-[10px] text-slate-400">comisión</div>
                  </div>
                </div>
              ))}
            </div>
          )}
        </div>
      </div>
    </div>
  );
}

function KpiCard({
  title,
  value,
  sub,
  delta,
  deltaSuffix,
  icon: Icon,
  color,
}: {
  title: string;
  value: string;
  sub?: string;
  delta?: number;
  deltaSuffix?: string;
  icon: React.ComponentType<{ className?: string }>;
  color: string;
}) {
  const positive = (delta ?? 0) >= 0;
  return (
    <div className="card relative overflow-hidden p-5">
      <div className="absolute -right-6 -top-6 h-24 w-24 rounded-full opacity-10" style={{ background: color }} />
      <div className="flex items-start justify-between">
        <div className="min-w-0">
          <div className="text-xs font-semibold uppercase tracking-wider text-slate-500">{title}</div>
          <div className="mt-1 text-2xl font-extrabold tracking-tight text-slate-900">{value}</div>
          {sub && <div className="mt-0.5 text-xs text-slate-500">{sub}</div>}
        </div>
        <div
          className="flex h-10 w-10 shrink-0 items-center justify-center rounded-xl text-white shadow-soft"
          style={{ background: color }}
        >
          <Icon className="h-5 w-5" />
        </div>
      </div>
      {delta !== undefined && (
        <div
          className={cn(
            "mt-3 inline-flex items-center gap-1 rounded-full px-2 py-0.5 text-xs font-bold",
            positive ? "bg-emerald-50 text-emerald-700" : "bg-rose-50 text-rose-700"
          )}
        >
          {positive ? <TrendingUp className="h-3 w-3" /> : <TrendingDown className="h-3 w-3" />}
          {positive ? "+" : ""}{delta}%
          <span className="font-medium opacity-70">{deltaSuffix}</span>
        </div>
      )}
    </div>
  );
}

interface RankItem {
  id: number;
  rank: number;
  title: string;
  subtitle?: string;
  value: string;
  extra?: string;
  color?: string;
  tags?: string | null;
}

function RankCard({
  title,
  subtitle,
  icon: Icon,
  iconColor,
  items,
  barMode,
}: {
  title: string;
  subtitle?: string;
  icon: React.ComponentType<{ className?: string }>;
  iconColor: string;
  items: RankItem[];
  barMode?: boolean;
}) {
  const maxVal = Math.max(...items.map((i) => parseFloat(i.value.replace(/[^0-9.]/g, "")) || 0), 1);
  return (
    <div className="card p-5">
      <div className="mb-4 flex items-center gap-2">
        <div
          className="flex h-8 w-8 items-center justify-center rounded-lg text-white"
          style={{ background: iconColor }}
        >
          <Icon className="h-4 w-4" />
        </div>
        <div>
          <h3 className="text-sm font-bold text-slate-900">{title}</h3>
          {subtitle && <p className="text-xs text-slate-500">{subtitle}</p>}
        </div>
      </div>
      {items.length === 0 ? (
        <EmptyState title="Sin datos" />
      ) : (
        <div className="space-y-2.5">
          {items.map((it) => (
            <div key={it.id} className="flex items-center gap-3">
              <div
                className={cn(
                  "flex h-7 w-7 shrink-0 items-center justify-center rounded-lg text-xs font-bold",
                  it.rank === 1
                    ? "bg-amber-100 text-amber-700"
                    : it.rank === 2
                    ? "bg-slate-200 text-slate-600"
                    : it.rank === 3
                    ? "bg-orange-100 text-orange-700"
                    : "bg-slate-100 text-slate-500"
                )}
              >
                {it.rank === 1 ? <Star className="h-3.5 w-3.5 fill-current" /> : it.rank}
              </div>
              <div className="min-w-0 flex-1">
                <div className="flex items-center justify-between gap-2">
                  <div className="flex min-w-0 items-center gap-1.5">
                    {it.color && <span className="h-2 w-2 shrink-0 rounded-full" style={{ background: it.color }} />}
                    <span className="truncate text-sm font-bold text-slate-800">{it.title}</span>
                    {it.tags?.split(",")[0] && (
                      <span className="chip bg-slate-100 text-slate-500">{it.tags.split(",")[0]}</span>
                    )}
                  </div>
                  <span className="shrink-0 text-sm font-bold text-slate-900">{it.value}</span>
                </div>
                <div className="mt-0.5 flex items-center justify-between gap-2">
                  {it.subtitle && <span className="truncate text-[11px] text-slate-500">{it.subtitle}</span>}
                  {it.extra && <span className="shrink-0 text-[11px] font-medium text-slate-400">{it.extra}</span>}
                </div>
                {barMode && (
                  <div className="mt-1 h-1 overflow-hidden rounded-full bg-slate-100">
                    <div
                      className="h-full rounded-full"
                      style={{
                        width: `${(parseFloat(it.value.replace(/[^0-9.]/g, "")) / maxVal) * 100}%`,
                        background: it.color ?? iconColor,
                      }}
                    />
                  </div>
                )}
              </div>
            </div>
          ))}
        </div>
      )}
    </div>
  );
}