'use client';

import { DailyMetrics } from '@/services/metrics';

interface ProductivityInsightsProps {
  data: DailyMetrics[];
  className?: string;
}

export function ProductivityInsights({ data, className }: ProductivityInsightsProps) {
  // Calculer les insights
  const totalCompleted = data.reduce((sum, day) => sum + day.completed, 0);
  const totalCreated = data.reduce((sum, day) => sum + day.newTasks, 0);
  // const averageCompletion = data.reduce((sum, day) => sum + day.completionRate, 0) / data.length;
  
  // Trouver le jour le plus productif
  const mostProductiveDay = data.reduce((best, day) => 
    day.completed > best.completed ? day : best
  );
  
  // Trouver le jour avec le plus de nouvelles tâches
  const mostCreativeDay = data.reduce((best, day) => 
    day.newTasks > best.newTasks ? day : best
  );
  
  // Analyser la tendance
  const firstHalf = data.slice(0, Math.ceil(data.length / 2));
  const secondHalf = data.slice(Math.ceil(data.length / 2));
  
  const firstHalfAvg = firstHalf.reduce((sum, day) => sum + day.completed, 0) / firstHalf.length;
  const secondHalfAvg = secondHalf.reduce((sum, day) => sum + day.completed, 0) / secondHalf.length;
  
  const trend = secondHalfAvg > firstHalfAvg ? 'up' : secondHalfAvg < firstHalfAvg ? 'down' : 'stable';
  
  // Calculer la consistance (écart-type faible = plus consistant)
  const avgCompleted = totalCompleted / data.length;
  const variance = data.reduce((sum, day) => {
    const diff = day.completed - avgCompleted;
    return sum + diff * diff;
  }, 0) / data.length;
  const standardDeviation = Math.sqrt(variance);
  const consistencyScore = Math.max(0, 100 - (standardDeviation * 10)); // Score sur 100

  // Ratio création/completion
  const creationRatio = totalCreated > 0 ? (totalCompleted / totalCreated) * 100 : 0;

  const getTrendIcon = () => {
    switch (trend) {
      case 'up': return { icon: '📈', color: 'text-green-600', label: 'En amélioration' };
      case 'down': return { icon: '📉', color: 'text-red-600', label: 'En baisse' };
      default: return { icon: '➡️', color: 'text-blue-600', label: 'Stable' };
    }
  };

  const getConsistencyLevel = () => {
    if (consistencyScore >= 80) return { label: 'Très régulier', color: 'text-green-600', icon: '🎯' };
    if (consistencyScore >= 60) return { label: 'Assez régulier', color: 'text-blue-600', icon: '📊' };
    if (consistencyScore >= 40) return { label: 'Variable', color: 'text-yellow-600', icon: '📊' };
    return { label: 'Très variable', color: 'text-red-600', icon: '📊' };
  };

  const getRatioStatus = () => {
    if (creationRatio >= 100) return { label: 'Équilibré+', color: 'text-green-600', icon: '⚖️' };
    if (creationRatio >= 80) return { label: 'Bien équilibré', color: 'text-blue-600', icon: '⚖️' };
    if (creationRatio >= 60) return { label: 'Légèrement en retard', color: 'text-yellow-600', icon: '⚖️' };
    return { label: 'Accumulation', color: 'text-red-600', icon: '⚖️' };
  };

  const trendInfo = getTrendIcon();
  const consistencyInfo = getConsistencyLevel();
  const ratioInfo = getRatioStatus();

  return (
    <div className={className}>
      <div className="space-y-4">
        {/* Insights principaux */}
        <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
          {/* Jour le plus productif */}
          <div className="p-4 bg-green-50 dark:bg-green-950/20 rounded-lg">
            <div className="flex items-center justify-between mb-2">
              <h4 className="font-medium text-green-900 dark:text-green-100">
                🏆 Jour champion
              </h4>
              <span className="text-2xl font-bold text-green-600">
                {mostProductiveDay.completed}
              </span>
            </div>
            <p className="text-sm text-green-800 dark:text-green-200">
              {mostProductiveDay.dayName} - {mostProductiveDay.completed} tâches terminées
            </p>
            <p className="text-xs text-green-600 mt-1">
              Taux: {mostProductiveDay.completionRate.toFixed(1)}%
            </p>
          </div>

          {/* Jour le plus créatif */}
          <div className="p-4 bg-blue-50 dark:bg-blue-950/20 rounded-lg">
            <div className="flex items-center justify-between mb-2">
              <h4 className="font-medium text-blue-900 dark:text-blue-100">
                💡 Jour créatif
              </h4>
              <span className="text-2xl font-bold text-blue-600">
                {mostCreativeDay.newTasks}
              </span>
            </div>
            <p className="text-sm text-blue-800 dark:text-blue-200">
              {mostCreativeDay.dayName} - {mostCreativeDay.newTasks} nouvelles tâches
            </p>
            <p className="text-xs text-blue-600 mt-1">
              {mostCreativeDay.dayName === mostProductiveDay.dayName ? 
                'Également jour le plus productif!' : 
                'Journée de planification'}
            </p>
          </div>
        </div>

        {/* Analyses comportementales */}
        <div className="grid grid-cols-1 md:grid-cols-3 gap-4">
          {/* Tendance */}
          <div className="p-4 bg-[var(--card)] border border-[var(--border)] rounded-lg">
            <div className="flex items-center gap-2 mb-2">
              <span className="text-2xl">{trendInfo.icon}</span>
              <h4 className="font-medium text-[var(--foreground)]">Tendance</h4>
            </div>
            <p className={`text-sm font-medium ${trendInfo.color}`}>
              {trendInfo.label}
            </p>
            <p className="text-xs text-[var(--muted-foreground)] mt-1">
              {secondHalfAvg > firstHalfAvg ? 
                `+${(((secondHalfAvg - firstHalfAvg) / firstHalfAvg) * 100).toFixed(1)}%` :
                `${(((secondHalfAvg - firstHalfAvg) / firstHalfAvg) * 100).toFixed(1)}%`}
            </p>
          </div>

          {/* Consistance */}
          <div className="p-4 bg-[var(--card)] border border-[var(--border)] rounded-lg">
            <div className="flex items-center gap-2 mb-2">
              <span className="text-2xl">{consistencyInfo.icon}</span>
              <h4 className="font-medium text-[var(--foreground)]">Régularité</h4>
            </div>
            <p className={`text-sm font-medium ${consistencyInfo.color}`}>
              {consistencyInfo.label}
            </p>
            <p className="text-xs text-[var(--muted-foreground)] mt-1">
              Score: {consistencyScore.toFixed(0)}/100
            </p>
          </div>

          {/* Ratio Création/Completion */}
          <div className="p-4 bg-[var(--card)] border border-[var(--border)] rounded-lg">
            <div className="flex items-center gap-2 mb-2">
              <span className="text-2xl">{ratioInfo.icon}</span>
              <h4 className="font-medium text-[var(--foreground)]">Équilibre</h4>
            </div>
            <p className={`text-sm font-medium ${ratioInfo.color}`}>
              {ratioInfo.label}
            </p>
            <p className="text-xs text-[var(--muted-foreground)] mt-1">
              {creationRatio.toFixed(0)}% de completion
            </p>
          </div>
        </div>

        {/* Recommandations */}
        <div className="p-4 bg-yellow-50 dark:bg-yellow-950/20 rounded-lg">
          <h4 className="font-medium text-yellow-900 dark:text-yellow-100 mb-2 flex items-center gap-2">
            💡 Recommandations
          </h4>
          <div className="space-y-1 text-sm text-yellow-800 dark:text-yellow-200">
            {trend === 'down' && (
              <p>• Essayez de retrouver votre rythme du début de semaine</p>
            )}
            {consistencyScore < 60 && (
              <p>• Essayez de maintenir un rythme plus régulier</p>
            )}
            {creationRatio < 80 && (
              <p>• Concentrez-vous plus sur terminer les tâches existantes</p>
            )}
            {creationRatio > 120 && (
              <p>• Excellent rythme! Peut-être ralentir la création de nouvelles tâches</p>
            )}
            {mostProductiveDay.dayName === mostCreativeDay.dayName && (
              <p>• Excellente synergie création/exécution le {mostProductiveDay.dayName}</p>
            )}
          </div>
        </div>
      </div>
    </div>
  );
}