'use client';

import { useEffect, useState } from 'react';
import { getPeers, listPins, checkHealth, getRepoStats, getBWStats } from '@/lib/api';
import type { RepoStats, BWStats } from '@/lib/api';
import PortalLayout from '@/app/layout-portal';
import Link from 'next/link';
import {
  HardDrive,
  Globe,
  Wifi,
  Database,
  Server,
  ArrowUpRight,
  ArrowDownLeft,
  BarChart3,
  Fingerprint,
} from 'lucide-react';

interface PeerData { id: string; addr: string; latency: string }
interface PinData { cid: string; name: string; size: number }

export default function DashboardPage() {
  const [peers, setPeers] = useState<PeerData[]>([]);
  const [pins, setPins] = useState<PinData[]>([]);
  const [health, setHealth] = useState<{ status: string; node: string } | null>(null);
  const [repo, setRepo] = useState<RepoStats | null>(null);
  const [bw, setBW] = useState<BWStats | null>(null);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    async function load() {
      try {
        const [h, p, pinList, r, b] = await Promise.all([
          checkHealth().catch(() => null),
          getPeers().catch(() => [] as PeerData[]),
          listPins().catch(() => [] as PinData[]),
          getRepoStats().catch(() => null),
          getBWStats().catch(() => null),
        ]);
        setHealth(h);
        setPeers(p);
        setPins(pinList);
        setRepo(r);
        setBW(b);
      } finally {
        setLoading(false);
      }
    }
    load();
    const iv = setInterval(load, 15000);
    return () => clearInterval(iv);
  }, []);

  const repoSizeGb = repo ? (repo.repoSize / 1e9).toFixed(2) : '—';
  const bwIn = bw ? (bw.totalIn / 1e6).toFixed(1) : '—';
  const bwOut = bw ? (bw.totalOut / 1e6).toFixed(1) : '—';

  const stats = [
    { label: 'Peers', value: peers.length, icon: Wifi, color: 'text-accent-cyan', bg: 'bg-accent-cyan/10' },
    { label: 'Pins', value: pins.length, icon: HardDrive, color: 'text-accent-purple', bg: 'bg-accent-purple/10' },
    { label: 'Node', value: health?.status ?? '—', icon: Server, color: 'text-accent-green', bg: 'bg-accent-green/10' },
    { label: 'Repo', value: `${repoSizeGb} GB`, icon: Database, color: 'text-accent-amber', bg: 'bg-accent-amber/10' },
  ];

  return (
    <PortalLayout>
      {/* Page header */}
      <div className="mb-8 flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-bold text-white">Dashboard</h1>
          <p className="text-sm text-surface-400 mt-1">IPFS node overview, storage, and bandwidth</p>
        </div>
        {loading && (
          <div className="flex items-center gap-2 text-xs text-surface-500">
            <div className="w-3 h-3 rounded-full border border-surface-600 border-t-transparent animate-spin" />
            refreshing…
          </div>
        )}
      </div>

      {/* Stat cards */}
      <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4 mb-8">
        {stats.map((s) => (
          <div key={s.label} className="glass rounded-xl p-5 animate-fade-in">
            <div className="flex items-center justify-between mb-3">
              <div className={`p-2 rounded-lg ${s.bg}`}>
                <s.icon className={`w-4 h-4 ${s.color}`} />
              </div>
              <ArrowUpRight className="w-3.5 h-3.5 text-surface-500" />
            </div>
            <div className="text-2xl font-bold text-white">{s.value}</div>
            <div className="text-xs text-surface-400 mt-1">{s.label}</div>
          </div>
        ))}
      </div>

      {/* Row 2: Peer + Bandwidth */}
      <div className="grid grid-cols-1 lg:grid-cols-3 gap-6 mb-6">
        {/* Peers list */}
        <div className="glass rounded-xl p-5 animate-fade-in">
          <h2 className="text-sm font-semibold text-white mb-4 flex items-center justify-between">
            <span className="flex items-center gap-2"><Wifi className="w-4 h-4 text-accent-cyan" />Connected Peers</span>
            <span className="text-xs text-surface-500">{peers.length} peer{peers.length !== 1 ? 's' : ''}</span>
          </h2>
          {peers.length === 0 ? (
            <p className="text-sm text-surface-500">No peers connected</p>
          ) : (
            <div className="space-y-1.5 max-h-56 overflow-y-auto">
              {peers.slice(0, 20).map((p) => (
                <div key={p.id} className="flex items-center justify-between py-1.5 border-b border-surface-800/50 last:border-0">
                  <div className="truncate max-w-[180px] text-sm text-surface-300 font-mono text-[11px]">
                    {p.id.slice(0, 20)}…
                  </div>
                  <div className="flex items-center gap-2">
                    <span className="text-[11px] text-surface-500">{p.latency}</span>
                    <span className="w-1.5 h-1.5 rounded-full bg-accent-green" />
                  </div>
                </div>
              ))}
            </div>
          )}
          <div className="mt-3 pt-3 border-t border-surface-800">
            <Link href="/peers" className="text-xs text-brand-400 hover:text-brand-300 transition-colors">
              View all peers →
            </Link>
          </div>
        </div>

        {/* Bandwidth */}
        <div className="glass rounded-xl p-5 animate-fade-in">
          <h2 className="text-sm font-semibold text-white mb-4 flex items-center gap-2">
            <BarChart3 className="w-4 h-4 text-accent-amber" />
            Bandwidth
          </h2>
          <div className="space-y-4">
            <div className="flex items-center justify-between p-3 rounded-lg bg-surface-900/50 border border-surface-800">
              <div className="flex items-center gap-2">
                <ArrowDownLeft className="w-4 h-4 text-accent-green" />
                <span className="text-xs text-surface-400">In</span>
              </div>
              <span className="text-sm font-semibold text-surface-200">{bwIn} MB</span>
            </div>
            <div className="flex items-center justify-between p-3 rounded-lg bg-surface-900/50 border border-surface-800">
              <div className="flex items-center gap-2">
                <ArrowUpRight className="w-4 h-4 text-accent-rose" />
                <span className="text-xs text-surface-400">Out</span>
              </div>
              <span className="text-sm font-semibold text-surface-200">{bwOut} MB</span>
            </div>
            <div className="text-xs text-surface-500 text-center">Total since node start</div>
          </div>
        </div>

        {/* IPNS quick */}
        <div className="glass rounded-xl p-5 animate-fade-in">
          <h2 className="text-sm font-semibold text-white mb-4 flex items-center gap-2">
            <Fingerprint className="w-4 h-4 text-accent-purple" />
            IPNS Names
          </h2>
          <p className="text-xs text-surface-400 mb-4">
            Publish CIDs to human-readable IPNS names, or resolve existing names.
          </p>
          <div className="flex flex-col gap-2">
            <Link
              href="/ipns"
              className="flex items-center justify-between px-3 py-2.5 rounded-lg bg-surface-900/50 border border-surface-800 hover:border-surface-700 text-sm text-surface-300 hover:text-white transition-colors"
            >
              <span>Manage IPNS Keys</span>
              <ArrowUpRight className="w-3.5 h-3.5 text-surface-500" />
            </Link>
            <Link
              href="/explorer"
              className="flex items-center justify-between px-3 py-2.5 rounded-lg bg-surface-900/50 border border-surface-800 hover:border-surface-700 text-sm text-surface-300 hover:text-white transition-colors"
            >
              <span>Browse Explorer</span>
              <ArrowUpRight className="w-3.5 h-3.5 text-surface-500" />
            </Link>
          </div>
        </div>
      </div>

      {/* Row 3: Pins + Repo details */}
      <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
        {/* Pins */}
        <div className="glass rounded-xl p-5 animate-fade-in">
          <h2 className="text-sm font-semibold text-white mb-4 flex items-center justify-between">
            <span className="flex items-center gap-2"><HardDrive className="w-4 h-4 text-accent-purple" />Recent Pins</span>
            <span className="text-xs text-surface-500">{pins.length} total</span>
          </h2>
          {pins.length === 0 ? (
            <p className="text-sm text-surface-500">No pins yet — upload or add content to get started.</p>
          ) : (
            <div className="space-y-1.5 max-h-56 overflow-y-auto">
              {pins.slice(0, 8).map((pin) => (
                <div key={pin.cid} className="flex items-center justify-between py-1.5 border-b border-surface-800/50 last:border-0">
                  <div className="truncate max-w-[240px] text-sm text-surface-300 font-mono text-[11px]">
                    {pin.name || pin.cid.slice(0, 24) + '…'}
                  </div>
                  <div className="text-[11px] text-surface-500">
                    {(pin.size / 1024).toFixed(1)} KB
                  </div>
                </div>
              ))}
            </div>
          )}
          <div className="mt-3 pt-3 border-t border-surface-800 flex gap-3">
            <Link href="/pins" className="text-xs text-brand-400 hover:text-brand-300 transition-colors">
              Manage pins →
            </Link>
            <Link href="/upload" className="text-xs text-brand-400 hover:text-brand-300 transition-colors">
              Upload new →
            </Link>
          </div>
        </div>

        {/* Repo Details */}
        <div className="glass rounded-xl p-5 animate-fade-in">
          <h2 className="text-sm font-semibold text-white mb-4 flex items-center gap-2">
            <Database className="w-4 h-4 text-accent-amber" />
            Repository
          </h2>
          {repo ? (
            <div className="space-y-3">
              <div className="flex justify-between py-2 border-b border-surface-800/50">
                <span className="text-xs text-surface-400">Size</span>
                <span className="text-xs text-surface-200 font-mono">{repoSizeGb} GB</span>
              </div>
              <div className="flex justify-between py-2 border-b border-surface-800/50">
                <span className="text-xs text-surface-400">Objects</span>
                <span className="text-xs text-surface-200">{repo.numObjects.toLocaleString()}</span>
              </div>
              <div className="flex justify-between py-2 border-b border-surface-800/50">
                <span className="text-xs text-surface-400">Storage Max</span>
                <span className="text-xs text-surface-200">{(repo.storageMax / 1e9).toFixed(1)} GB</span>
              </div>
              <div className="flex justify-between py-2 border-b border-surface-800/50">
                <span className="text-xs text-surface-400">Version</span>
                <span className="text-xs text-surface-200 font-mono">{repo.version || health?.node || '—'}</span>
              </div>
              <div className="flex justify-between py-2">
                <span className="text-xs text-surface-400">Path</span>
                <span className="text-xs text-surface-500 font-mono truncate max-w-[200px]" title={repo.repoPath}>{repo.repoPath}</span>
              </div>
            </div>
          ) : (
            <p className="text-sm text-surface-500">Repo stats unavailable (Kubo may not expose /api/v0/repo/stat via gateway).</p>
          )}
        </div>
      </div>
    </PortalLayout>
  );
}