import React, { useState } from 'react';
import {
  HardDrive,
  Database,
  Plus,
  RefreshCw,
  Clock,
  RotateCcw,
  CheckCircle2,
  AlertTriangle,
  FolderTree,
  FileBox,
  ShieldCheck,
} from 'lucide-react';
import type { ZfsPool, ZfsDataset, ZfsSnapshot, UnimportedPool } from '../types/index.js';

interface StorageViewProps {
  pools: ZfsPool[];
  datasets: ZfsDataset[];
  snapshots: ZfsSnapshot[];
  unimportedPools: UnimportedPool[];
  onRefresh: () => void;
  onImportPool: (poolName: string) => Promise<void>;
  onScrubPool: (poolName: string) => Promise<void>;
  onCreateSnapshot: (dataset: string, tag: string) => Promise<void>;
  onRollbackSnapshot: (snapshotName: string) => Promise<void>;
}

export const StorageView: React.FC<StorageViewProps> = ({
  pools,
  datasets,
  snapshots,
  unimportedPools,
  onRefresh,
  onImportPool,
  onScrubPool,
  onCreateSnapshot,
  onRollbackSnapshot,
}) => {
  const [activeSubTab, setActiveSubTab] = useState<'pools' | 'datasets' | 'snapshots' | 'migration'>('pools');
  const [selectedPool, setSelectedPool] = useState<string>(pools[0]?.name || 'tank');
  const [importingPoolName, setImportingPoolName] = useState<string | null>(null);
  const [importSuccess, setImportSuccess] = useState<string | null>(null);

  const handleImport = async (poolName: string) => {
    setImportingPoolName(poolName);
    try {
      await onImportPool(poolName);
      setImportSuccess(`Pool '${poolName}' was successfully imported without data loss!`);
      setTimeout(() => setImportSuccess(null), 6000);
    } finally {
      setImportingPoolName(null);
    }
  };

  return (
    <div className="space-y-6">
      {/* Sub-navigation Header */}
      <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-4 border-b border-slate-800 pb-4">
        <div>
          <h2 className="text-xl font-bold text-white tracking-tight">OpenZFS Storage Engine</h2>
          <p className="text-xs text-slate-400 mt-0.5">
            Enterprise storage layout, datasets, snapshot policies, and foreign pool migration
          </p>
        </div>

        <div className="flex items-center gap-1.5 p-1 bg-slate-900 border border-slate-800 rounded-xl">
          <button
            onClick={() => setActiveSubTab('pools')}
            className={`px-3 py-1.5 rounded-lg text-xs font-medium transition ${
              activeSubTab === 'pools'
                ? 'bg-emerald-600 text-white shadow-sm'
                : 'text-slate-400 hover:text-white'
            }`}
          >
            Storage Pools ({pools.length})
          </button>
          <button
            onClick={() => setActiveSubTab('datasets')}
            className={`px-3 py-1.5 rounded-lg text-xs font-medium transition ${
              activeSubTab === 'datasets'
                ? 'bg-emerald-600 text-white shadow-sm'
                : 'text-slate-400 hover:text-white'
            }`}
          >
            Datasets ({datasets.length})
          </button>
          <button
            onClick={() => setActiveSubTab('snapshots')}
            className={`px-3 py-1.5 rounded-lg text-xs font-medium transition ${
              activeSubTab === 'snapshots'
                ? 'bg-emerald-600 text-white shadow-sm'
                : 'text-slate-400 hover:text-white'
            }`}
          >
            Snapshots ({snapshots.length})
          </button>
          <button
            onClick={() => setActiveSubTab('migration')}
            className={`flex items-center gap-1 px-3 py-1.5 rounded-lg text-xs font-medium transition ${
              activeSubTab === 'migration'
                ? 'bg-amber-600 text-white shadow-sm'
                : 'text-amber-400 hover:bg-amber-500/10'
            }`}
          >
            <span>Pool Migration</span>
            {unimportedPools.length > 0 && (
              <span className="h-2 w-2 rounded-full bg-amber-400 animate-ping" />
            )}
          </button>
        </div>
      </div>

      {importSuccess && (
        <div className="p-4 rounded-xl bg-emerald-500/10 border border-emerald-500/30 flex items-center gap-3 text-emerald-300 text-xs">
          <CheckCircle2 className="h-5 w-5 text-emerald-400 shrink-0" />
          <span>{importSuccess}</span>
        </div>
      )}

      {/* Pools Tab */}
      {activeSubTab === 'pools' && (
        <div className="space-y-4">
          {pools.map((pool) => (
            <div key={pool.name} className="p-6 rounded-2xl bg-slate-900/80 border border-slate-800 space-y-4">
              <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-3">
                <div className="flex items-center gap-3">
                  <div className="p-2 rounded-xl bg-slate-800 text-emerald-400">
                    <Database className="h-5 w-5" />
                  </div>
                  <div>
                    <h3 className="text-base font-bold text-white flex items-center gap-2">
                      <span>{pool.name}</span>
                      <span className="text-[10px] px-2 py-0.5 rounded-full bg-emerald-500/10 text-emerald-400 border border-emerald-500/20 font-semibold font-mono">
                        {pool.health}
                      </span>
                    </h3>
                    <p className="text-xs text-slate-400 mt-0.5">
                      OpenZFS Pool • ashift=12 • Compression=lz4/zstd
                    </p>
                  </div>
                </div>

                <div className="flex items-center gap-2">
                  <button
                    onClick={() => onScrubPool(pool.name)}
                    className="flex items-center gap-1.5 px-3 py-1.5 rounded-lg bg-slate-800 hover:bg-slate-700 text-slate-200 text-xs font-medium border border-slate-700 transition"
                  >
                    <RefreshCw className="h-3.5 w-3.5" />
                    <span>Run Scrub</span>
                  </button>
                </div>
              </div>

              {/* Pool Capacity Bar */}
              <div className="space-y-1.5">
                <div className="flex justify-between text-xs text-slate-300">
                  <span>Capacity Used: <strong>{pool.allocated}</strong> / {pool.size} ({pool.capacityPercent}%)</span>
                  <span>Available Free: <strong>{pool.free}</strong></span>
                </div>
                <div className="w-full bg-slate-800 h-2.5 rounded-full overflow-hidden">
                  <div
                    className="bg-emerald-500 h-full rounded-full transition-all duration-500"
                    style={{ width: `${pool.capacityPercent}%` }}
                  />
                </div>
              </div>

              {/* Status summary */}
              <div className="pt-2 border-t border-slate-800/80 flex flex-wrap items-center justify-between text-xs text-slate-400 gap-2">
                <span>Last Scrub: {pool.scanStatus || 'Completed with 0 errors'}</span>
                <span>Fragmentation: <strong className="text-slate-200 font-mono">{pool.fragmentation}</strong></span>
              </div>
            </div>
          ))}
        </div>
      )}

      {/* Datasets Tab */}
      {activeSubTab === 'datasets' && (
        <div className="rounded-2xl bg-slate-900/80 border border-slate-800 overflow-hidden">
          <div className="p-4 border-b border-slate-800 flex items-center justify-between">
            <h3 className="text-sm font-semibold text-white flex items-center gap-2">
              <FolderTree className="h-4 w-4 text-emerald-400" />
              <span>ZFS Datasets & Mountpoints</span>
            </h3>
            <span className="text-xs text-slate-400">Total {datasets.length} datasets</span>
          </div>

          <div className="overflow-x-auto">
            <table className="w-full text-left text-xs">
              <thead className="bg-slate-950/60 text-slate-400 border-b border-slate-800 font-medium">
                <tr>
                  <th className="px-5 py-3">Dataset Name</th>
                  <th className="px-4 py-3">Mountpoint</th>
                  <th className="px-4 py-3">Used</th>
                  <th className="px-4 py-3">Available</th>
                  <th className="px-4 py-3">Compression</th>
                  <th className="px-4 py-3">Record Size</th>
                  <th className="px-4 py-3">Quota</th>
                </tr>
              </thead>
              <tbody className="divide-y divide-slate-800/60 text-slate-300">
                {datasets.map((ds) => (
                  <tr key={ds.name} className="hover:bg-slate-800/30 transition">
                    <td className="px-5 py-3.5 font-medium text-white flex items-center gap-2 font-mono">
                      <FileBox className="h-3.5 w-3.5 text-slate-400 shrink-0" />
                      <span>{ds.name}</span>
                    </td>
                    <td className="px-4 py-3.5 font-mono text-slate-400">{ds.mountpoint}</td>
                    <td className="px-4 py-3.5 font-mono text-emerald-400 font-semibold">{ds.used}</td>
                    <td className="px-4 py-3.5 font-mono text-slate-400">{ds.available}</td>
                    <td className="px-4 py-3.5 font-mono">
                      <span className="px-2 py-0.5 rounded bg-slate-800 text-slate-300">
                        {ds.compression}
                      </span>
                    </td>
                    <td className="px-4 py-3.5 font-mono text-slate-400">{ds.recordsize}</td>
                    <td className="px-4 py-3.5 font-mono text-slate-400">
                      {ds.quota === 'none' ? <span className="text-slate-600">None</span> : ds.quota}
                    </td>
                  </tr>
                ))}
              </tbody>
            </table>
          </div>
        </div>
      )}

      {/* Snapshots Tab */}
      {activeSubTab === 'snapshots' && (
        <div className="rounded-2xl bg-slate-900/80 border border-slate-800 overflow-hidden">
          <div className="p-4 border-b border-slate-800 flex items-center justify-between">
            <h3 className="text-sm font-semibold text-white flex items-center gap-2">
              <Clock className="h-4 w-4 text-emerald-400" />
              <span>ZFS Point-in-Time Snapshots</span>
            </h3>
            <span className="text-xs text-slate-400">Total {snapshots.length} snapshots</span>
          </div>

          <div className="overflow-x-auto">
            <table className="w-full text-left text-xs">
              <thead className="bg-slate-950/60 text-slate-400 border-b border-slate-800 font-medium">
                <tr>
                  <th className="px-5 py-3">Snapshot Name</th>
                  <th className="px-4 py-3">Dataset</th>
                  <th className="px-4 py-3">Created</th>
                  <th className="px-4 py-3">Unique Used</th>
                  <th className="px-4 py-3 text-right">Actions</th>
                </tr>
              </thead>
              <tbody className="divide-y divide-slate-800/60 text-slate-300">
                {snapshots.map((snap) => (
                  <tr key={snap.name} className="hover:bg-slate-800/30 transition">
                    <td className="px-5 py-3 font-mono font-medium text-white">{snap.name}</td>
                    <td className="px-4 py-3 font-mono text-slate-400">{snap.dataset}</td>
                    <td className="px-4 py-3 text-slate-400">{snap.creationTime}</td>
                    <td className="px-4 py-3 font-mono text-emerald-400">{snap.usedBytes}</td>
                    <td className="px-4 py-3 text-right">
                      <button
                        onClick={() => onRollbackSnapshot(snap.name)}
                        className="inline-flex items-center gap-1 px-2.5 py-1 rounded bg-slate-800 hover:bg-rose-500/20 text-slate-300 hover:text-rose-300 text-[11px] font-medium transition border border-slate-700"
                        title="Rollback dataset to this exact snapshot state"
                      >
                        <RotateCcw className="h-3 w-3" />
                        <span>Rollback</span>
                      </button>
                    </td>
                  </tr>
                ))}
              </tbody>
            </table>
          </div>
        </div>
      )}

      {/* Foreign Pool Migration Wizard */}
      {activeSubTab === 'migration' && (
        <div className="space-y-4">
          <div className="p-6 rounded-2xl bg-amber-500/5 border border-amber-500/20 space-y-3">
            <div className="flex items-center gap-2.5 text-amber-400 font-semibold text-sm">
              <ShieldCheck className="h-5 w-5" />
              <span>Zero-Data-Loss Migration Engine</span>
            </div>
            <p className="text-xs text-slate-300 leading-relaxed">
              NaxOS provides first-class support for discovering and safely importing existing ZFS storage pools created on <strong>TrueNAS CORE/SCALE</strong> or raw <strong>NixOS systems (such as nixos-lukas)</strong>. The migration engine operates with safety-first guarantees: existing datasets, quotas, and critical application assets (such as your Immich photo library in <code>tank/media/photos</code>) are preserved untouched.
            </p>
          </div>

          <div className="p-6 rounded-2xl bg-slate-900/80 border border-slate-800 space-y-4">
            <div className="flex items-center justify-between">
              <div>
                <h3 className="text-sm font-semibold text-white">Detected Foreign ZFS Pools</h3>
                <p className="text-xs text-slate-400 mt-0.5">Unimported pools ready for adoption</p>
              </div>
              <button
                onClick={onRefresh}
                className="flex items-center gap-1.5 px-3 py-1.5 rounded-lg bg-slate-800 hover:bg-slate-700 text-xs font-medium text-slate-200 border border-slate-700 transition"
              >
                <RefreshCw className="h-3.5 w-3.5" />
                <span>Re-scan Disks</span>
              </button>
            </div>

            {unimportedPools.length === 0 ? (
              <div className="py-8 text-center text-xs text-slate-500">
                No foreign unimported pools detected. All connected pools are currently active.
              </div>
            ) : (
              <div className="space-y-3">
                {unimportedPools.map((pool) => (
                  <div key={pool.name} className="p-4 rounded-xl bg-slate-950/70 border border-slate-800 flex flex-col md:flex-row md:items-center justify-between gap-4">
                    <div>
                      <div className="flex items-center gap-2">
                        <span className="font-bold text-white font-mono">{pool.name}</span>
                        <span className="text-[10px] px-2 py-0.5 rounded-full bg-emerald-500/10 text-emerald-400 font-semibold border border-emerald-500/20">
                          {pool.state}
                        </span>
                        <span className="text-xs text-slate-500 font-mono">ID: {pool.id}</span>
                      </div>
                      <p className="text-xs text-slate-400 mt-1">{pool.status}</p>
                      <div className="flex items-center gap-2 mt-2 text-[11px] text-slate-500">
                        <span>Member Disks:</span>
                        {pool.disks.map((d) => (
                          <span key={d} className="px-1.5 py-0.5 rounded bg-slate-800 text-slate-300 font-mono">
                            {d}
                          </span>
                        ))}
                      </div>
                    </div>

                    <button
                      onClick={() => handleImport(pool.name)}
                      disabled={importingPoolName === pool.name}
                      className="px-4 py-2 rounded-xl bg-emerald-600 hover:bg-emerald-500 disabled:opacity-50 text-white text-xs font-semibold shadow-sm transition shrink-0"
                    >
                      {importingPoolName === pool.name ? 'Importing Safely...' : 'Safe Import & Adopt'}
                    </button>
                  </div>
                ))}
              </div>
            )}
          </div>
        </div>
      )}
    </div>
  );
};