import { DemandSignal, DemandItem } from '../../lib/demand/types';

interface DemandSignalCardProps {
  signal: DemandSignal;
  onViewDetails?: () => void;
}

const STATUS_COLORS: Record<DemandSignal['supplyStatus'], { bg: string; text: string; icon: string }> = {
  surplus: { bg: 'bg-green-100', text: 'text-green-800', icon: '📈' },
  balanced: { bg: 'bg-blue-100', text: 'text-blue-800', icon: '⚖️' },
  shortage: { bg: 'bg-yellow-100', text: 'text-yellow-800', icon: '⚠️' },
  critical: { bg: 'bg-red-100', text: 'text-red-800', icon: '🚨' },
};

function formatCategory(category: string): string {
  return category.replace(/_/g, ' ').replace(/\b\w/g, (l) => l.toUpperCase());
}

export default function DemandSignalCard({ signal, onViewDetails }: DemandSignalCardProps) {
  const statusStyle = STATUS_COLORS[signal.supplyStatus];

  // Get top demand items
  const topItems = [...signal.demandItems]
    .sort((a, b) => b.weeklyDemandKg - a.weeklyDemandKg)
    .slice(0, 5);

  const gapPercentage = signal.totalWeeklyDemandKg > 0
    ? (signal.supplyGapKg / signal.totalWeeklyDemandKg) * 100
    : 0;

  return (
    <div className="bg-white rounded-lg shadow-lg overflow-hidden">
      {/* Header */}
      <div className="bg-gradient-to-r from-blue-600 to-indigo-600 text-white p-4">
        <div className="flex items-center justify-between">
          <div>
            <h3 className="text-lg font-bold">{signal.region.name}</h3>
            <p className="text-blue-200 text-sm">
              {signal.seasonalPeriod.charAt(0).toUpperCase() + signal.seasonalPeriod.slice(1)} Season
            </p>
          </div>
          <div className={`px-3 py-1 rounded-full ${statusStyle.bg}`}>
            <span className={`text-sm font-semibold ${statusStyle.text}`}>
              {statusStyle.icon} {signal.supplyStatus.charAt(0).toUpperCase() + signal.supplyStatus.slice(1)}
            </span>
          </div>
        </div>
      </div>

      <div className="p-6 space-y-4">
        {/* Key metrics */}
        <div className="grid grid-cols-3 gap-4">
          <div className="text-center p-3 bg-gray-50 rounded-lg">
            <p className="text-2xl font-bold text-gray-900">{signal.totalConsumers}</p>
            <p className="text-xs text-gray-500">Consumers</p>
          </div>
          <div className="text-center p-3 bg-blue-50 rounded-lg">
            <p className="text-2xl font-bold text-blue-600">{signal.totalWeeklyDemandKg.toFixed(0)}</p>
            <p className="text-xs text-gray-500">Weekly Demand (kg)</p>
          </div>
          <div className="text-center p-3 bg-green-50 rounded-lg">
            <p className="text-2xl font-bold text-green-600">{signal.currentSupplyKg.toFixed(0)}</p>
            <p className="text-xs text-gray-500">Current Supply (kg)</p>
          </div>
        </div>

        {/* Supply Gap Indicator */}
        <div className="p-4 bg-gray-50 rounded-lg">
          <div className="flex justify-between items-center mb-2">
            <span className="text-sm font-medium text-gray-700">Supply Coverage</span>
            <span className={`text-sm font-bold ${gapPercentage > 20 ? 'text-red-600' : 'text-green-600'}`}>
              {(100 - gapPercentage).toFixed(0)}% covered
            </span>
          </div>
          <div className="w-full bg-gray-200 rounded-full h-3">
            <div
              className={`h-3 rounded-full transition-all ${
                gapPercentage > 50 ? 'bg-red-500' : gapPercentage > 20 ? 'bg-yellow-500' : 'bg-green-500'
              }`}
              style={{ width: `${Math.min(100 - gapPercentage, 100)}%` }}
            ></div>
          </div>
          {signal.supplyGapKg > 0 && (
            <p className="text-xs text-red-600 mt-2">
              Gap: {signal.supplyGapKg.toFixed(0)} kg needed
            </p>
          )}
        </div>

        {/* Top Demand Items */}
        <div>
          <h4 className="text-sm font-semibold text-gray-900 mb-3">Top Demanded Items</h4>
          <div className="space-y-2">
            {topItems.map((item, index) => (
              <DemandItemRow key={index} item={item} rank={index + 1} />
            ))}
          </div>
        </div>

        {/* Confidence indicator */}
        <div className="flex items-center justify-between pt-4 border-t border-gray-200">
          <div className="flex items-center gap-2">
            <span className="text-sm text-gray-500">Confidence:</span>
            <div className="flex gap-1">
              {[1, 2, 3, 4, 5].map((level) => (
                <div
                  key={level}
                  className={`w-2 h-4 rounded-sm ${
                    level <= signal.confidenceLevel / 20 ? 'bg-green-500' : 'bg-gray-200'
                  }`}
                ></div>
              ))}
            </div>
            <span className="text-sm text-gray-600">{signal.confidenceLevel}%</span>
          </div>
          <span className="text-xs text-gray-400">
            Updated: {new Date(signal.timestamp).toLocaleDateString()}
          </span>
        </div>

        {/* View Details Button */}
        {onViewDetails && (
          <button
            onClick={onViewDetails}
            className="w-full mt-4 py-2 px-4 bg-indigo-600 hover:bg-indigo-700 text-white font-medium rounded-lg transition"
          >
            View Full Details
          </button>
        )}
      </div>
    </div>
  );
}

function DemandItemRow({ item, rank }: { item: DemandItem; rank: number }) {
  const urgencyColors: Record<DemandItem['urgency'], string> = {
    immediate: 'bg-red-100 text-red-700',
    this_week: 'bg-orange-100 text-orange-700',
    this_month: 'bg-yellow-100 text-yellow-700',
    next_season: 'bg-blue-100 text-blue-700',
  };

  return (
    <div className="flex items-center p-2 bg-gray-50 rounded-lg hover:bg-gray-100 transition">
      <span className="w-6 h-6 flex items-center justify-center bg-indigo-100 text-indigo-700 rounded-full text-xs font-bold">
        {rank}
      </span>
      <div className="ml-3 flex-1">
        <p className="text-sm font-medium text-gray-900">{item.produceType}</p>
        <p className="text-xs text-gray-500">{formatCategory(item.category)}</p>
      </div>
      <div className="text-right">
        <p className="text-sm font-bold text-gray-900">{item.weeklyDemandKg.toFixed(1)} kg</p>
        <span className={`text-xs px-2 py-0.5 rounded-full ${urgencyColors[item.urgency]}`}>
          {item.urgency.replace(/_/g, ' ')}
        </span>
      </div>
      {item.inSeason && (
        <span className="ml-2 text-green-500" title="In Season">🌿</span>
      )}
    </div>
  );
}