/**
 * Admin Dashboard Page
 * Main dashboard for admin users showing ML models, agents, and system health
 */

import { useState, useEffect } from 'react';
import {
  CpuChipIcon,
  ChartBarIcon,
  UserGroupIcon,
  ServerIcon,
  ArrowTrendingUpIcon,
  ArrowTrendingDownIcon,
  CheckCircleIcon,
  ExclamationTriangleIcon,
  XCircleIcon,
} from '@heroicons/react/24/solid';
import {
  getAdminDashboard,
  getSystemHealth,
  getMLModels,
  getAgents,
  type AdminStats,
  type SystemHealth,
  type MLModel,
  type AgentPerformance,
} from '../../../services/adminService';

export default function AdminDashboard() {
  const [stats, setStats] = useState<AdminStats | null>(null);
  const [health, setHealth] = useState<SystemHealth | null>(null);
  const [models, setModels] = useState<MLModel[]>([]);
  const [agents, setAgents] = useState<AgentPerformance[]>([]);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    loadDashboardData();
  }, []);

  const loadDashboardData = async () => {
    setLoading(true);
    try {
      const [dashboardData, healthData, modelsData, agentsData] = await Promise.all([
        getAdminDashboard(),
        getSystemHealth(),
        getMLModels(),
        getAgents(),
      ]);

      setStats(dashboardData);
      setHealth(healthData);
      setModels(Array.isArray(modelsData) ? modelsData : []);
      setAgents(Array.isArray(agentsData) ? agentsData : []);
    } catch (error) {
      console.error('Error loading dashboard data:', error);
    } finally {
      setLoading(false);
    }
  };

  const getHealthIcon = (status: string) => {
    switch (status) {
      case 'healthy':
        return <CheckCircleIcon className="w-5 h-5 text-green-400" />;
      case 'degraded':
        return <ExclamationTriangleIcon className="w-5 h-5 text-yellow-400" />;
      default:
        return <XCircleIcon className="w-5 h-5 text-red-400" />;
    }
  };

  const formatCurrency = (value: number) => {
    return new Intl.NumberFormat('en-US', {
      style: 'currency',
      currency: 'USD',
      minimumFractionDigits: 2,
    }).format(value);
  };

  if (loading) {
    return (
      <div className="flex items-center justify-center min-h-screen">
        <div className="animate-spin rounded-full h-12 w-12 border-t-2 border-b-2 border-primary-500"></div>
      </div>
    );
  }

  return (
    <div className="p-6 space-y-6">
      {/* Header */}
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-bold text-white">Admin Dashboard</h1>
          <p className="text-gray-400">OrbiQuant IA Platform Overview</p>
        </div>
        <button
          onClick={loadDashboardData}
          className="px-4 py-2 bg-primary-600 hover:bg-primary-700 text-white rounded-lg transition-colors"
        >
          Refresh Data
        </button>
      </div>

      {/* System Health Banner */}
      {health && (
        <div className={`p-4 rounded-lg ${
          health.status === 'healthy' ? 'bg-green-900/30 border border-green-700' :
          health.status === 'degraded' ? 'bg-yellow-900/30 border border-yellow-700' :
          'bg-red-900/30 border border-red-700'
        }`}>
          <div className="flex items-center gap-3">
            {getHealthIcon(health.status)}
            <span className="text-white font-semibold">
              System Status: {health.status.charAt(0).toUpperCase() + health.status.slice(1)}
            </span>
            <span className="text-gray-400 text-sm ml-auto">
              Last updated: {new Date(health.timestamp).toLocaleString()}
            </span>
          </div>
        </div>
      )}

      {/* Stats Grid */}
      <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-4">
        {/* ML Models Card */}
        <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
          <div className="flex items-center gap-3 mb-3">
            <div className="p-2 bg-blue-600 rounded-lg">
              <CpuChipIcon className="w-6 h-6 text-white" />
            </div>
            <span className="text-gray-400">ML Models</span>
          </div>
          <p className="text-3xl font-bold text-white">{models.length}</p>
          <p className="text-sm text-green-400">
            {models.filter(m => m.status === 'active' || m.status === 'training').length} active
          </p>
        </div>

        {/* Trading Agents Card */}
        <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
          <div className="flex items-center gap-3 mb-3">
            <div className="p-2 bg-purple-600 rounded-lg">
              <UserGroupIcon className="w-6 h-6 text-white" />
            </div>
            <span className="text-gray-400">Trading Agents</span>
          </div>
          <p className="text-3xl font-bold text-white">{agents.length}</p>
          <p className="text-sm text-green-400">
            {agents.filter(a => a.status === 'active').length} running
          </p>
        </div>

        {/* Total P&L Card */}
        <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
          <div className="flex items-center gap-3 mb-3">
            <div className="p-2 bg-green-600 rounded-lg">
              <ChartBarIcon className="w-6 h-6 text-white" />
            </div>
            <span className="text-gray-400">Today's P&L</span>
          </div>
          <p className={`text-3xl font-bold ${(stats?.total_pnl_today || 0) >= 0 ? 'text-green-400' : 'text-red-400'}`}>
            {formatCurrency(stats?.total_pnl_today || 0)}
          </p>
          <div className="flex items-center gap-1 text-sm">
            {(stats?.total_pnl_today || 0) >= 0 ? (
              <ArrowTrendingUpIcon className="w-4 h-4 text-green-400" />
            ) : (
              <ArrowTrendingDownIcon className="w-4 h-4 text-red-400" />
            )}
            <span className="text-gray-400">vs yesterday</span>
          </div>
        </div>

        {/* Predictions Card */}
        <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
          <div className="flex items-center gap-3 mb-3">
            <div className="p-2 bg-orange-600 rounded-lg">
              <ServerIcon className="w-6 h-6 text-white" />
            </div>
            <span className="text-gray-400">Predictions Today</span>
          </div>
          <p className="text-3xl font-bold text-white">{stats?.total_predictions_today || 0}</p>
          <p className="text-sm text-blue-400">
            {((stats?.overall_accuracy || 0) * 100).toFixed(1)}% accuracy
          </p>
        </div>
      </div>

      {/* Services Health */}
      {health && (
        <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
          <h2 className="text-lg font-bold text-white mb-4">Services Health</h2>
          <div className="grid grid-cols-1 md:grid-cols-3 gap-4">
            <div className="flex items-center justify-between p-4 bg-gray-900 rounded-lg">
              <div className="flex items-center gap-3">
                <ServerIcon className="w-5 h-5 text-gray-400" />
                <span className="text-white">Database</span>
              </div>
              {getHealthIcon(health.services.database.status)}
            </div>
            <div className="flex items-center justify-between p-4 bg-gray-900 rounded-lg">
              <div className="flex items-center gap-3">
                <CpuChipIcon className="w-5 h-5 text-gray-400" />
                <span className="text-white">ML Engine</span>
              </div>
              {getHealthIcon(health.services.mlEngine.status)}
            </div>
            <div className="flex items-center justify-between p-4 bg-gray-900 rounded-lg">
              <div className="flex items-center gap-3">
                <UserGroupIcon className="w-5 h-5 text-gray-400" />
                <span className="text-white">Trading Agents</span>
              </div>
              {getHealthIcon(health.services.tradingAgents.status)}
            </div>
          </div>
        </div>
      )}

      {/* ML Models Overview */}
      <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
        <div className="flex items-center justify-between mb-4">
          <h2 className="text-lg font-bold text-white">ML Models</h2>
          <a href="/admin/models" className="text-primary-400 hover:text-primary-300 text-sm">
            View All
          </a>
        </div>
        <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4">
          {models.slice(0, 6).map((model, index) => (
            <div key={index} className="p-4 bg-gray-900 rounded-lg">
              <div className="flex items-center justify-between mb-2">
                <span className="text-white font-semibold">{model.name || model.type}</span>
                <span className={`px-2 py-1 rounded-full text-xs font-semibold ${
                  model.status === 'active' ? 'bg-green-900/50 text-green-400' :
                  model.status === 'training' ? 'bg-yellow-900/50 text-yellow-400' :
                  'bg-gray-700 text-gray-400'
                }`}>
                  {model.status}
                </span>
              </div>
              <div className="text-sm text-gray-400">
                <span>Accuracy: {((model.accuracy || 0) * 100).toFixed(1)}%</span>
              </div>
            </div>
          ))}
        </div>
      </div>

      {/* Trading Agents Overview */}
      <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
        <div className="flex items-center justify-between mb-4">
          <h2 className="text-lg font-bold text-white">Trading Agents</h2>
          <a href="/admin/agents" className="text-primary-400 hover:text-primary-300 text-sm">
            View All
          </a>
        </div>
        <div className="grid grid-cols-1 md:grid-cols-3 gap-4">
          {agents.map((agent, index) => (
            <div key={index} className="p-4 bg-gray-900 rounded-lg">
              <div className="flex items-center justify-between mb-3">
                <span className="text-white font-semibold">{agent.name}</span>
                <span className={`px-2 py-1 rounded-full text-xs font-semibold ${
                  agent.status === 'active' ? 'bg-green-900/50 text-green-400' :
                  agent.status === 'paused' ? 'bg-yellow-900/50 text-yellow-400' :
                  'bg-red-900/50 text-red-400'
                }`}>
                  {agent.status}
                </span>
              </div>
              <div className="space-y-2">
                <div className="flex justify-between text-sm">
                  <span className="text-gray-400">Win Rate</span>
                  <span className="text-white">{((agent.win_rate || 0) * 100).toFixed(1)}%</span>
                </div>
                <div className="flex justify-between text-sm">
                  <span className="text-gray-400">Total P&L</span>
                  <span className={agent.total_pnl >= 0 ? 'text-green-400' : 'text-red-400'}>
                    {formatCurrency(agent.total_pnl || 0)}
                  </span>
                </div>
                <div className="flex justify-between text-sm">
                  <span className="text-gray-400">Trades</span>
                  <span className="text-white">{agent.total_trades || 0}</span>
                </div>
              </div>
            </div>
          ))}
          {agents.length === 0 && (
            <div className="col-span-3 text-center text-gray-500 py-8">
              No trading agents configured yet
            </div>
          )}
        </div>
      </div>

      {/* System Info */}
      {health && (
        <div className="bg-gray-800 rounded-xl p-5 border border-gray-700">
          <h2 className="text-lg font-bold text-white mb-4">System Info</h2>
          <div className="grid grid-cols-1 md:grid-cols-3 gap-4">
            <div className="p-4 bg-gray-900 rounded-lg">
              <span className="text-gray-400 text-sm">Uptime</span>
              <p className="text-white font-semibold">
                {Math.floor(health.system.uptime / 3600)}h {Math.floor((health.system.uptime % 3600) / 60)}m
              </p>
            </div>
            <div className="p-4 bg-gray-900 rounded-lg">
              <span className="text-gray-400 text-sm">Memory Usage</span>
              <p className="text-white font-semibold">
                {health.system.memory.percentage.toFixed(1)}%
              </p>
            </div>
            <div className="p-4 bg-gray-900 rounded-lg">
              <span className="text-gray-400 text-sm">Last Update</span>
              <p className="text-white font-semibold">
                {new Date(health.timestamp).toLocaleTimeString()}
              </p>
            </div>
          </div>
        </div>
      )}
    </div>
  );
}