'use client'

import { useState } from 'react'
import { Panel } from '@/components/cluster/Panel'
import { SlotMeter } from '@/components/cluster/SlotMeter'
import { models, namespaces, nodes, type Node } from '@/lib/clusterMock'

function Cells({ filled, total, tone = 'flux' }: { filled: number; total: number; tone?: 'flux' | 'rose' }) {
  return (
    <div className="flex gap-[2px]" aria-label={`${filled} of ${total} running`}>
      {Array.from({ length: total }, (_, i) => (
        <span
          key={i}
          className={`h-2.5 w-[5px] rounded-[1px] ${i < filled ? (tone === 'rose' ? 'bg-rose' : 'bg-flux') : 'bg-wire'}`}
        />
      ))}
    </div>
  )
}

function NodeCard({ node, active, onSelect }: { node: Node; active: boolean; onSelect: () => void }) {
  const isGpu = node.gpu > 0
  return (
    <button
      onClick={onSelect}
      aria-pressed={active}
      className={[
        'group relative border p-4 text-left transition-colors',
        'focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-lamp',
        active ? 'border-lamp bg-riser' : 'border-wire bg-deck hover:border-wire-lit',
      ].join(' ')}
    >
      {isGpu && <span className="absolute right-0 top-0 h-6 w-px bg-lamp" />}
      <div className="flex items-baseline justify-between">
        <h3 className="font-signage text-xl font-semibold tracking-signage">{node.name}</h3>
        <span className={`h-1.5 w-1.5 rounded-full ${node.health === 'healthy' ? 'bg-flux' : 'bg-rose'}`} />
      </div>
      <p className={`mt-1 font-data text-[10px] uppercase tracking-[0.14em] ${isGpu ? 'text-lamp' : 'text-dim'}`}>
        {node.role}
      </p>

      <dl className="mt-4 space-y-1.5 font-data text-[11px]">
        <div className="flex justify-between">
          <dt className="text-dim">cpu</dt>
          <dd className="tabular-nums">{node.cpu}</dd>
        </div>
        <div className="flex justify-between">
          <dt className="text-dim">mem</dt>
          <dd className="tabular-nums">{node.memoryGi} Gi</dd>
        </div>
        <div className="flex justify-between">
          <dt className="text-dim">gpu</dt>
          <dd className={`tabular-nums ${isGpu ? 'text-lamp' : 'text-dim'}`}>{node.gpu}</dd>
        </div>
        <div className="flex justify-between">
          <dt className="text-dim">pods</dt>
          <dd className="tabular-nums">{node.pods}</dd>
        </div>
      </dl>
    </button>
  )
}

export default function TopologyPage() {
  const [selected, setSelected] = useState('worker-1')

  return (
    <div className="space-y-6">
      {/* Thesis: the constraint that shaped everything downstream. */}
      <header className="border border-wire bg-deck p-6 md:p-8">
        <p className="font-data text-[10px] uppercase tracking-[0.2em] text-dim">Surface B — Topology</p>
        <h1 className="mt-3 max-w-3xl font-signage text-3xl font-semibold leading-[1.1] tracking-signage md:text-5xl">
          Four nodes. One GPU. <span className="text-lamp">Eight sequence slots</span> for everything that thinks.
        </h1>
        <div className="mt-6 flex flex-wrap items-center gap-4">
          <SlotMeter used={3} size="lg" showCap />
        </div>
        <p className="mt-6 max-w-2xl font-plex text-sm leading-relaxed text-dim">
          Every workload below runs on hardware sitting in one room. The scarcest thing in it is inference
          capacity, so that is the number this page keeps in front of you.
        </p>
      </header>

      <div className="grid gap-4 sm:grid-cols-2 xl:grid-cols-4">
        {nodes.map((n) => (
          <NodeCard key={n.name} node={n} active={selected === n.name} onSelect={() => setSelected(n.name)} />
        ))}
      </div>

      <div className="grid gap-6 lg:grid-cols-[1.4fr_1fr]">
        <Panel label="Namespaces" hint="pods running / scheduled">
          <ul className="space-y-1.5">
            {namespaces.map((ns) => {
              const short = ns.running < ns.total
              return (
                <li key={ns.name} className="flex items-center gap-4 py-0.5">
                  <span className="w-40 shrink-0 truncate font-data text-[11px] text-chalk">{ns.name}</span>
                  <Cells filled={ns.running} total={ns.total} tone={ns.running === 0 ? 'rose' : 'flux'} />
                  <span
                    className={`ml-auto shrink-0 font-data text-[11px] tabular-nums ${short ? 'text-lamp' : 'text-dim'}`}
                  >
                    {ns.running}/{ns.total}
                  </span>
                </li>
              )
            })}
          </ul>
        </Panel>

        <div className="space-y-6">
          <Panel label="Inference" hint="KServe · worker-1">
            <ul className="space-y-3">
              {models.map((m) => (
                <li key={m.name} className="border-b border-wire pb-3 last:border-0 last:pb-0">
                  <div className="flex items-baseline justify-between">
                    <span className="font-signage text-base font-semibold tracking-signage">{m.name}</span>
                    <span className={`font-data text-[10px] uppercase tracking-[0.14em] ${m.ready ? 'text-flux' : 'text-rose'}`}>
                      {m.ready ? 'ready' : 'down'}
                    </span>
                  </div>
                  <p className="mt-1 font-data text-[10px] text-dim">
                    {m.replicas}× replica · {m.seqPerReplica} seq · {m.contextTokens.toLocaleString()} ctx
                  </p>
                </li>
              ))}
            </ul>
          </Panel>

          <Panel label="Withheld" hint="redaction allowlist">
            <ul className="space-y-1.5 font-data text-[10px] text-dim">
              {['node and pod addresses', 'container arguments', 'image tags and digests', 'source repository URLs', 'Secret names', 'condition messages'].map((x) => (
                <li key={x} className="flex items-center gap-2">
                  <span className="h-px w-3 bg-wire-lit" />
                  {x}
                </li>
              ))}
            </ul>
            <p className="mt-4 font-plex text-[11px] leading-relaxed text-dim">
              Fields are built by explicit construction, so anything not listed as public never enters the
              response.
            </p>
          </Panel>
        </div>
      </div>
    </div>
  )
}