import type { ResourceSample, ResourceScope, SystemResources } from "@umt/contracts";
import { Activity, Cpu, HardDrive, MemoryStick, Network } from "lucide-react";
import { type ReactNode, useState } from "react";
import { Line, LineChart, ResponsiveContainer, Tooltip, YAxis } from "recharts";
import { useSystemResources } from "~/api/system.ts";
import { ErrorState, LoadingState } from "~/components/console/empty-state.tsx";
import { Tabs, TabsList, TabsTrigger } from "~/components/ui/tabs.tsx";
import { formatDuration } from "~/lib/labels.ts";
import { cn, formatBytes } from "~/lib/utils.ts";

// 资源监控(界面第二轮,参考 MP 仪表盘的 CPU / 内存 / 网络组件):四块磁贴,每块一个当前值 + 小趋势线。
// 图表沿用运行状态页的无彩口径:前景色细线,一张图一个量;网络收 / 发两条线靠线型与图例区分。

const SCOPE_LABEL: Record<ResourceScope, string> = { cgroup: "本容器", host: "整机", none: "取不到" };

const pct = (v: number | null | undefined) => (v == null ? "—" : `${Math.round(v)}%`);
const rate = (v: number | null | undefined) => (v == null ? "—" : `${formatBytes(v, 1)}/s`);

/** 用量分档:≥ 90% 红、≥ 75% 黄(只给数值上色,文字仍写清) */
export function usageTone(v: number | null | undefined): string {
  if (v == null) return "text-foreground";
  return v >= 90 ? "text-destructive" : v >= 75 ? "text-warning" : "text-foreground";
}

type Key = Exclude<keyof ResourceSample, "at">;

function clock(iso: string) {
  return new Date(iso).toLocaleTimeString("zh-CN", {
    hour: "2-digit",
    minute: "2-digit",
    second: "2-digit",
    hour12: false,
  });
}

/** 小趋势线:无坐标轴,悬停看时间与数值 */
export function Sparkline({
  samples,
  keys,
  format,
  max,
  height = 48,
  label,
}: {
  samples: ResourceSample[];
  keys: { key: Key; name: string; dash?: string }[];
  format: (v: number) => string;
  /** 纵轴上限(百分比类给 100,保持刻度稳定) */
  max?: number;
  height?: number;
  label: string;
}) {
  const has = samples.some((s) => keys.some((k) => s[k.key] != null));
  if (!has)
    return (
      <div className="flex items-center text-meta text-muted-foreground" style={{ height }}>
        采样中…
      </div>
    );
  return (
    <div role="img" aria-label={label} className="text-muted-foreground" style={{ height }}>
      <ResponsiveContainer width="100%" height="100%">
        <LineChart data={samples} margin={{ top: 4, right: 2, bottom: 2, left: 2 }}>
          <YAxis hide domain={[0, max ?? "auto"]} />
          <Tooltip
            labelFormatter={(_, p) => (p?.[0]?.payload?.at ? clock(String(p[0].payload.at)) : "")}
            formatter={(v, name) => [format(Number(v)), String(name)]}
            contentStyle={{
              background: "var(--color-popover)",
              border: "1px solid var(--color-border)",
              borderRadius: 12,
              fontSize: 12,
              color: "var(--color-foreground)",
            }}
            cursor={{ stroke: "var(--color-muted-foreground)", strokeDasharray: "3 3" }}
          />
          {keys.map((k, i) => (
            <Line
              key={k.key}
              type="monotone"
              dataKey={k.key}
              name={k.name}
              stroke="var(--color-foreground)"
              strokeOpacity={i ? 0.5 : 0.85}
              strokeDasharray={k.dash}
              strokeWidth={2}
              dot={false}
              activeDot={{ r: 4, strokeWidth: 2, stroke: "var(--color-background)" }}
              connectNulls
              isAnimationActive={false}
            />
          ))}
        </LineChart>
      </ResponsiveContainer>
    </div>
  );
}

function Tile({
  icon: Icon,
  title,
  scope,
  value,
  valueClass,
  hint,
  children,
}: {
  icon: typeof Cpu;
  title: string;
  scope: ResourceScope;
  value: ReactNode;
  valueClass?: string;
  hint: ReactNode;
  children: ReactNode;
}) {
  return (
    <section className="pg-slab min-w-0 rounded-xl p-4">
      <div className="flex items-center gap-1.5 text-meta text-muted-foreground">
        <Icon className="h-3.5 w-3.5" aria-hidden />
        <span>{title}</span>
        <span className="ml-auto">{SCOPE_LABEL[scope]}</span>
      </div>
      <p className={cn("mt-1 text-title-sm font-semibold tabular-nums", valueClass)}>{value}</p>
      <p className="mt-0.5 truncate text-meta text-muted-foreground tabular-nums">{hint}</p>
      <div className="mt-2">{children}</div>
    </section>
  );
}

/** 最近 n 分钟平均(MP 的 1m / 5m / 15m 平均) */
function avg(samples: ResourceSample[], key: Key, minutes: number): number | null {
  const from = Date.now() - minutes * 60_000;
  const v = samples
    .filter((s) => Date.parse(s.at) >= from)
    .map((s) => s[key])
    .filter((x): x is number => x != null);
  return v.length ? v.reduce((a, b) => a + b, 0) / v.length : null;
}

export function ResourceTiles({ d }: { d: SystemResources }) {
  const m = d.memory;
  return (
    <div className="grid gap-4 sm:grid-cols-2 xl:grid-cols-4">
      <Tile
        icon={Cpu}
        title="CPU"
        scope={d.cpu.scope}
        value={pct(d.cpu.percent)}
        valueClass={usageTone(d.cpu.percent)}
        hint={
          <>
            {d.cpu.cores ? `${d.cpu.cores} 核` : ""}
            {d.cpu.load ? ` · 负载 ${d.cpu.load.map((x) => x.toFixed(2)).join(" / ")}` : ""}
            {` · 5 分钟平均 ${pct(avg(d.samples, "cpuPercent", 5))}`}
          </>
        }
      >
        <Sparkline
          samples={d.samples}
          keys={[{ key: "cpuPercent", name: "CPU" }]}
          format={(v) => `${v.toFixed(1)}%`}
          max={100}
          label="CPU 占用趋势"
        />
      </Tile>
      <Tile
        icon={MemoryStick}
        title="内存"
        scope={m.scope}
        value={pct(m.percent)}
        valueClass={usageTone(m.percent)}
        hint={
          <>
            {m.usedBytes != null ? formatBytes(m.usedBytes, 1) : "—"}
            {m.limitBytes != null ? ` / ${formatBytes(m.limitBytes, 1)}` : ""}
            {m.scope === "cgroup" && m.hostTotalBytes != null && m.hostAvailableBytes != null
              ? ` · 整机可用 ${formatBytes(m.hostAvailableBytes, 1)}`
              : ""}
          </>
        }
      >
        <Sparkline
          samples={d.samples}
          keys={[{ key: "memoryPercent", name: "内存" }]}
          format={(v) => `${v.toFixed(1)}%`}
          max={100}
          label="内存占用趋势"
        />
      </Tile>
      <Tile
        icon={Network}
        title="网络"
        scope={d.network.scope}
        value={
          <>
            <span className="text-caption font-normal text-muted-foreground">↓ </span>
            {rate(d.network.rxBps)}
          </>
        }
        hint={`↑ ${rate(d.network.txBps)}${d.network.rxTotalBytes != null ? ` · 累计收 ${formatBytes(d.network.rxTotalBytes, 1)}` : ""}`}
      >
        <Sparkline
          samples={d.samples}
          keys={[
            { key: "netRxBps", name: "接收" },
            { key: "netTxBps", name: "发送", dash: "4 3" },
          ]}
          format={(v) => `${formatBytes(v, 1)}/s`}
          label="网络吞吐趋势（实线接收，虚线发送）"
        />
      </Tile>
      <Tile
        icon={HardDrive}
        title="磁盘读写"
        scope={d.diskIo.scope}
        value={
          <>
            <span className="text-caption font-normal text-muted-foreground">读 </span>
            {rate(d.diskIo.readBps)}
          </>
        }
        hint={`写 ${rate(d.diskIo.writeBps)}${d.hostUptimeSec != null ? ` · 主机已运行 ${formatDuration(d.hostUptimeSec)}` : ""}`}
      >
        <Sparkline
          samples={d.samples}
          keys={[
            { key: "diskReadBps", name: "读" },
            { key: "diskWriteBps", name: "写", dash: "4 3" },
          ]}
          format={(v) => `${formatBytes(v, 1)}/s`}
          label="磁盘读写趋势（实线读，虚线写）"
        />
      </Tile>
    </div>
  );
}

const WINDOWS = [15, 60, 360];

/** 运行状态页「资源」节:窗口切换 + 四块磁贴 */
export function ResourceSection() {
  const [minutes, setMinutes] = useState(60);
  const q = useSystemResources(minutes);
  return (
    <section className="min-w-0">
      <div className="mb-3 flex flex-wrap items-center gap-2">
        <Activity className="h-4 w-4 text-muted-foreground" aria-hidden />
        <h2 className="text-body font-semibold text-foreground">资源</h2>
        <span className="text-meta text-muted-foreground">
          每 {q.data?.intervalSec ?? 5} 秒采样一次，只保留最近 6 小时（重启后重新累计）
        </span>
        <Tabs value={String(minutes)} onValueChange={(v) => setMinutes(Number(v))} className="ml-auto">
          <TabsList className="pb-0">
            {WINDOWS.map((n) => (
              <TabsTrigger key={n} value={String(n)} className="h-7 px-2.5 text-caption">
                {n < 60 ? `${n} 分钟` : `${n / 60} 小时`}
              </TabsTrigger>
            ))}
          </TabsList>
        </Tabs>
      </div>
      {q.isPending ? (
        <LoadingState rows={3} />
      ) : q.isError ? (
        <ErrorState plain error={q.error} onRetry={() => q.refetch()} />
      ) : (
        <ResourceTiles d={q.data} />
      )}
    </section>
  );
}