feat: enhance HomePage with tag metrics and analytics integration

- Added TagAnalyticsService to fetch tag distribution metrics for the HomePage.
- Updated HomePageClient and ProductivityAnalytics components to utilize new tag metrics.
- Refactored TagsClient to use utility functions for color validation and generation.
- Simplified TagForm to use centralized tag colors from TAG_COLORS.

src/app/page.tsx

@@ -2,6 +2,7 @@ import { tasksService } from '@/services/task-management/tasks';
 import { tagsService } from '@/services/task-management/tags';
 import { AnalyticsService } from '@/services/analytics/analytics';
 import { DeadlineAnalyticsService } from '@/services/analytics/deadline-analytics';
+import { TagAnalyticsService } from '@/services/analytics/tag-analytics';
 import { HomePageClient } from '@/components/HomePageClient';
 
 // Force dynamic rendering (no static generation)
@@ -9,12 +10,13 @@ export const dynamic = 'force-dynamic';
 
 export default async function HomePage() {
   // SSR - Récupération des données côté serveur
-  const [initialTasks, initialTags, initialStats, productivityMetrics, deadlineMetrics] = await Promise.all([
+  const [initialTasks, initialTags, initialStats, productivityMetrics, deadlineMetrics, tagMetrics] = await Promise.all([
     tasksService.getTasks(),
     tagsService.getTags(),
     tasksService.getTaskStats(),
     AnalyticsService.getProductivityMetrics(),
-    DeadlineAnalyticsService.getDeadlineMetrics()
+    DeadlineAnalyticsService.getDeadlineMetrics(),
+    TagAnalyticsService.getTagDistributionMetrics()
   ]);
 
   return (
@@ -24,6 +26,7 @@ export default async function HomePage() {
       initialStats={initialStats}
       productivityMetrics={productivityMetrics}
       deadlineMetrics={deadlineMetrics}
+      tagMetrics={tagMetrics}
     />
   );
 }

src/clients/tags-client.ts

@@ -1,5 +1,6 @@
 import { HttpClient } from './base/http-client';
 import { Tag } from '@/lib/types';
+import { generateRandomTagColor, isValidTagColor } from '@/lib/tag-colors';
 
 // Types pour les requêtes (now only used for validation - CRUD operations moved to server actions)
 
@@ -85,27 +86,14 @@ export class TagsClient extends HttpClient {
    * Valide le format d'une couleur hexadécimale
    */
   static isValidColor(color: string): boolean {
-    return /^#[0-9A-F]{6}$/i.test(color);
+    return isValidTagColor(color);
   }
 
   /**
    * Génère une couleur aléatoire pour un nouveau tag
    */
   static generateRandomColor(): string {
-    const colors = [
+    return generateRandomTagColor();
-      '#3B82F6', // Blue
-      '#EF4444', // Red
-      '#10B981', // Green
-      '#F59E0B', // Yellow
-      '#8B5CF6', // Purple
-      '#EC4899', // Pink
-      '#06B6D4', // Cyan
-      '#84CC16', // Lime
-      '#F97316', // Orange
-      '#6366F1', // Indigo
-    ];
-    
-    return colors[Math.floor(Math.random() * colors.length)];
   }
 
   /**

src/components/HomePageClient.tsx

@@ -13,6 +13,7 @@ import { WelcomeSection } from '@/components/dashboard/WelcomeSection';
 import { IntegrationFilter } from '@/components/dashboard/IntegrationFilter';
 import { ProductivityMetrics } from '@/services/analytics/analytics';
 import { DeadlineMetrics } from '@/services/analytics/deadline-analytics';
+import { TagDistributionMetrics } from '@/services/analytics/tag-analytics';
 import { useGlobalKeyboardShortcuts } from '@/hooks/useGlobalKeyboardShortcuts';
 
 interface HomePageClientProps {
@@ -21,12 +22,14 @@ interface HomePageClientProps {
   initialStats: TaskStats;
   productivityMetrics: ProductivityMetrics;
   deadlineMetrics: DeadlineMetrics;
+  tagMetrics: TagDistributionMetrics;
 }
 
 
-function HomePageContent({ productivityMetrics, deadlineMetrics }: { 
+function HomePageContent({ productivityMetrics, deadlineMetrics, tagMetrics }: { 
   productivityMetrics: ProductivityMetrics;
   deadlineMetrics: DeadlineMetrics;
+  tagMetrics: TagDistributionMetrics;
 }) {
   const { syncing, createTask, tasks } = useTasksContext();
   const [selectedSources, setSelectedSources] = useState<string[]>([]);
@@ -83,6 +86,7 @@ function HomePageContent({ productivityMetrics, deadlineMetrics }: {
         <ProductivityAnalytics 
           metrics={productivityMetrics}
           deadlineMetrics={deadlineMetrics}
+          tagMetrics={tagMetrics}
           selectedSources={selectedSources}
           hiddenSources={hiddenSources}
         />
@@ -99,7 +103,8 @@ export function HomePageClient({
   initialTags, 
   initialStats, 
   productivityMetrics, 
-  deadlineMetrics 
+  deadlineMetrics,
+  tagMetrics
 }: HomePageClientProps) {
   return (
     <TasksProvider 
@@ -110,6 +115,7 @@ export function HomePageClient({
       <HomePageContent 
         productivityMetrics={productivityMetrics}
         deadlineMetrics={deadlineMetrics}
+        tagMetrics={tagMetrics}
       />
     </TasksProvider>
   );

src/components/dashboard/ProductivityAnalytics.tsx

@@ -1,21 +1,24 @@
 import { useMemo } from 'react';
 import { ProductivityMetrics } from '@/services/analytics/analytics';
 import { DeadlineMetrics } from '@/services/analytics/deadline-analytics';
+import { TagDistributionMetrics } from '@/services/analytics/tag-analytics';
 import { CompletionTrendChart } from '@/components/charts/CompletionTrendChart';
 import { VelocityChart } from '@/components/charts/VelocityChart';
 import { PriorityDistributionChart } from '@/components/charts/PriorityDistributionChart';
 import { WeeklyStatsCard } from '@/components/charts/WeeklyStatsCard';
+import { TagDistributionChart } from '@/components/dashboard/TagDistributionChart';
 import { Card, MetricCard } from '@/components/ui';
 import { DeadlineOverview } from '@/components/deadline/DeadlineOverview';
 
 interface ProductivityAnalyticsProps {
   metrics: ProductivityMetrics;
   deadlineMetrics: DeadlineMetrics;
+  tagMetrics: TagDistributionMetrics;
   selectedSources: string[];
   hiddenSources?: string[];
 }
 
-export function ProductivityAnalytics({ metrics, deadlineMetrics, selectedSources, hiddenSources = [] }: ProductivityAnalyticsProps) {
+export function ProductivityAnalytics({ metrics, deadlineMetrics, tagMetrics, selectedSources, hiddenSources = [] }: ProductivityAnalyticsProps) {
 
   // Filtrer les métriques selon les sources sélectionnées
   const filteredMetrics = useMemo(() => {
@@ -133,6 +136,9 @@ export function ProductivityAnalytics({ metrics, deadlineMetrics, selectedSource
         </Card>
       </div>
 
+      {/* Distribution par Tags */}
+      <TagDistributionChart metrics={tagMetrics} />
+
       {/* Insights automatiques */}
       <Card className="p-6">
         <h3 className="text-lg font-semibold mb-4">💡 Insights</h3>

src/components/dashboard/TagDistributionChart.tsx

@@ -0,0 +1,204 @@
+'use client';
+
+import { Card } from '@/components/ui/Card';
+import { PieChart, Pie, Cell, ResponsiveContainer, Tooltip, Legend, BarChart, Bar, XAxis, YAxis, CartesianGrid, PieLabelRenderProps } from 'recharts';
+import { TagDistributionMetrics } from '@/services/analytics/tag-analytics';
+
+interface TagDistributionChartProps {
+  metrics: TagDistributionMetrics;
+  className?: string;
+}
+
+export function TagDistributionChart({ metrics, className }: TagDistributionChartProps) {
+  // Préparer les données pour le graphique en camembert
+  const pieData = metrics.tagDistribution.slice(0, 8).map((tag) => ({
+    name: tag.tagName,
+    value: tag.count,
+    percentage: tag.percentage,
+    color: tag.tagColor
+  }));
+
+  // Préparer les données pour le graphique en barres (top tags)
+  const barData = metrics.topTags.slice(0, 10).map(tag => ({
+    name: tag.tagName.length > 12 ? `${tag.tagName.substring(0, 12)}...` : tag.tagName,
+    usage: tag.usage,
+    completionRate: tag.completionRate,
+    avgPriority: tag.avgPriority,
+    color: tag.tagColor
+  }));
+
+  // Tooltip personnalisé pour le camembert
+  const PieTooltip = ({ active, payload }: { active?: boolean; payload?: Array<{ payload: { name: string; value: number; percentage: number } }> }) => {
+    if (active && payload && payload.length) {
+      const data = payload[0].payload;
+      return (
+        <div className="bg-[var(--card)] border border-[var(--border)] rounded-lg p-3 shadow-lg">
+          <p className="font-medium mb-1">{data.name}</p>
+          <p className="text-sm text-[var(--foreground)]">
+            {data.value} tâches ({data.percentage.toFixed(1)}%)
+          </p>
+        </div>
+      );
+    }
+    return null;
+  };
+
+  // Tooltip personnalisé pour les barres
+  const BarTooltip = ({ active, payload }: { active?: boolean; payload?: Array<{ payload: { name: string; usage: number; completionRate: number } }> }) => {
+    if (active && payload && payload.length) {
+      const data = payload[0].payload;
+      return (
+        <div className="bg-[var(--card)] border border-[var(--border)] rounded-lg p-3 shadow-lg">
+          <p className="font-medium mb-1">{data.name}</p>
+          <p className="text-sm text-[var(--foreground)]">
+            {data.usage} tâches
+          </p>
+          <p className="text-sm text-[var(--muted-foreground)]">
+            Taux de completion: {data.completionRate.toFixed(1)}%
+          </p>
+        </div>
+      );
+    }
+    return null;
+  };
+
+  // Légende personnalisée
+  const CustomLegend = ({ payload }: { payload?: Array<{ value: string; color: string }> }) => {
+    if (!payload) return null;
+    
+    return (
+      <div className="flex flex-wrap gap-2 mt-4">
+        {payload.map((entry, index) => (
+          <div key={index} className="flex items-center gap-2 text-sm">
+            <div 
+              className="w-3 h-3 rounded-full" 
+              style={{ backgroundColor: entry.color }}
+            />
+            <span className="text-[var(--foreground)]">{entry.value}</span>
+          </div>
+        ))}
+      </div>
+    );
+  };
+
+  return (
+    <div className={className}>
+      <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
+        {/* Distribution par tags - Camembert */}
+        <Card className="p-6">
+          <h3 className="text-lg font-semibold mb-4">🏷️ Distribution par Tags</h3>
+          
+          <div className="h-64">
+            <ResponsiveContainer width="100%" height="100%">
+              <PieChart>
+                <Pie
+                  data={pieData}
+                  cx="50%"
+                  cy="50%"
+                  labelLine={false}
+                  label={(props: PieLabelRenderProps) => {
+                    const { name, percent } = props;
+                    const percentValue = typeof percent === 'number' ? percent : 0;
+                    return percentValue > 0.05 ? `${name}: ${(percentValue * 100).toFixed(1)}%` : '';
+                  }}
+                  outerRadius={80}
+                  fill="#8884d8"
+                  dataKey="value"
+                  nameKey="name"
+                >
+                  {pieData.map((entry, index) => (
+                    <Cell key={`cell-${index}`} fill={entry.color} />
+                  ))}
+                </Pie>
+                <Tooltip content={<PieTooltip />} />
+                <Legend content={<CustomLegend />} />
+              </PieChart>
+            </ResponsiveContainer>
+          </div>
+        </Card>
+
+        {/* Top tags - Barres */}
+        <Card className="p-6">
+          <h3 className="text-lg font-semibold mb-4">📊 Top Tags par Usage</h3>
+          
+          <div className="h-64">
+            <ResponsiveContainer width="100%" height="100%">
+              <BarChart data={barData} margin={{ top: 20, right: 30, left: 20, bottom: 5 }}>
+                <CartesianGrid strokeDasharray="3 3" stroke="var(--border)" />
+                <XAxis 
+                  dataKey="name" 
+                  tick={{ fontSize: 12 }}
+                  angle={-45}
+                  textAnchor="end"
+                  height={80}
+                />
+                <YAxis tick={{ fontSize: 12 }} />
+                <Tooltip content={<BarTooltip />} />
+                <Bar 
+                  dataKey="usage" 
+                  radius={[4, 4, 0, 0]}
+                >
+                  {barData.map((entry, index) => (
+                    <Cell key={`cell-${index}`} fill={entry.color} />
+                  ))}
+                </Bar>
+              </BarChart>
+            </ResponsiveContainer>
+          </div>
+        </Card>
+      </div>
+
+      {/* Statistiques des tags */}
+      <Card className="p-6 mt-6">
+        <h3 className="text-lg font-semibold mb-4">📈 Statistiques des Tags</h3>
+        
+        <div className="grid grid-cols-2 md:grid-cols-5 gap-4">
+          <div className="text-center">
+            <div className="text-2xl font-bold text-[var(--primary)]">
+              {metrics.tagStats.totalTags}
+            </div>
+            <div className="text-sm text-[var(--muted-foreground)]">
+              Tags totaux
+            </div>
+          </div>
+          
+          <div className="text-center">
+            <div className="text-2xl font-bold text-[var(--success)]">
+              {metrics.tagStats.activeTags}
+            </div>
+            <div className="text-sm text-[var(--muted-foreground)]">
+              Tags actifs
+            </div>
+          </div>
+          
+          <div className="text-center">
+            <div className="text-lg font-semibold text-[var(--foreground)] truncate">
+              {metrics.tagStats.mostUsedTag}
+            </div>
+            <div className="text-sm text-[var(--muted-foreground)]">
+              Plus utilisé
+            </div>
+          </div>
+          
+          <div className="text-center">
+            <div className="text-lg font-semibold text-[var(--foreground)] truncate">
+              {metrics.tagStats.leastUsedTag}
+            </div>
+            <div className="text-sm text-[var(--muted-foreground)]">
+              Moins utilisé
+            </div>
+          </div>
+          
+          <div className="text-center">
+            <div className="text-2xl font-bold text-[var(--accent)]">
+              {metrics.tagStats.avgTasksPerTag.toFixed(1)}
+            </div>
+            <div className="text-sm text-[var(--muted-foreground)]">
+              Moy. tâches/tag
+            </div>
+          </div>
+        </div>
+      </Card>
+    </div>
+  );
+}

src/components/forms/TagForm.tsx

@@ -3,6 +3,7 @@
 import { useState, useEffect, useTransition } from 'react';
 import { Tag } from '@/lib/types';
 import { TagsClient } from '@/clients/tags-client';
+import { TAG_COLORS } from '@/lib/tag-colors';
 import { Modal } from '@/components/ui/Modal';
 import { Input } from '@/components/ui/Input';
 import { Button } from '@/components/ui/Button';
@@ -15,20 +16,7 @@ interface TagFormProps {
   tag?: Tag | null; // Si fourni, mode édition
 }
 
-const PRESET_COLORS = [
+const PRESET_COLORS = TAG_COLORS;
-  '#3B82F6', // Blue
-  '#EF4444', // Red
-  '#10B981', // Green
-  '#F59E0B', // Yellow
-  '#8B5CF6', // Purple
-  '#EC4899', // Pink
-  '#06B6D4', // Cyan
-  '#84CC16', // Lime
-  '#F97316', // Orange
-  '#6366F1', // Indigo
-  '#14B8A6', // Teal
-  '#F43F5E', // Rose
-];
 
 export function TagForm({ isOpen, onClose, onSuccess, tag }: TagFormProps) {
   const [isPending, startTransition] = useTransition();

src/lib/tag-colors.ts

@@ -0,0 +1,67 @@
+/**
+ * Lib centralisée pour la gestion des couleurs des tags
+ */
+
+// Couleurs prédéfinies pour les tags (cohérentes avec TagForm et TagsClient)
+export const TAG_COLORS = [
+  '#3B82F6', // Blue
+  '#EF4444', // Red
+  '#10B981', // Green
+  '#F59E0B', // Yellow
+  '#8B5CF6', // Purple
+  '#EC4899', // Pink
+  '#06B6D4', // Cyan
+  '#84CC16', // Lime
+  '#F97316', // Orange
+  '#6366F1', // Indigo
+  '#14B8A6', // Teal
+  '#F43F5E', // Rose
+  '#22C55E', // Emerald
+  '#EAB308', // Amber
+  '#A855F7', // Violet
+  '#D946EF', // Fuchsia
+] as const;
+
+/**
+ * Génère une couleur pour un tag basée sur son nom (hash déterministe)
+ */
+export function generateTagColor(tagName: string): string {
+  // Hash simple du nom pour choisir une couleur
+  let hash = 0;
+  for (let i = 0; i < tagName.length; i++) {
+    hash = tagName.charCodeAt(i) + ((hash << 5) - hash);
+  }
+  
+  return TAG_COLORS[Math.abs(hash) % TAG_COLORS.length];
+}
+
+/**
+ * Génère une couleur aléatoire pour un nouveau tag
+ */
+export function generateRandomTagColor(): string {
+  return TAG_COLORS[Math.floor(Math.random() * TAG_COLORS.length)];
+}
+
+/**
+ * Valide si une couleur est valide (format hex)
+ */
+export function isValidTagColor(color: string): boolean {
+  return /^#[0-9A-F]{6}$/i.test(color);
+}
+
+/**
+ * Récupère la couleur d'un tag, en générant une couleur par défaut si nécessaire
+ */
+export function getTagColor(tagName: string, existingColor?: string): string {
+  if (existingColor && isValidTagColor(existingColor)) {
+    return existingColor;
+  }
+  return generateTagColor(tagName);
+}
+
+/**
+ * Génère un tableau de couleurs pour les graphiques en respectant les couleurs des tags
+ */
+export function generateChartColors(tags: Array<{ name: string; color?: string }>): string[] {
+  return tags.map(tag => getTagColor(tag.name, tag.color));
+}

src/services/analytics/tag-analytics.ts

@@ -0,0 +1,274 @@
+import { prisma } from '@/services/core/database';
+import { Task, TaskStatus, TaskPriority, TaskSource } from '@/lib/types';
+import { getToday, subtractDays } from '@/lib/date-utils';
+import { getTagColor } from '@/lib/tag-colors';
+
+export interface TagDistributionMetrics {
+  tagDistribution: Array<{
+    tagName: string;
+    tagColor: string;
+    count: number;
+    percentage: number;
+    tasks: Array<{
+      id: string;
+      title: string;
+      status: TaskStatus;
+      priority: TaskPriority;
+    }>;
+  }>;
+  topTags: Array<{
+    tagName: string;
+    tagColor: string;
+    usage: number;
+    completionRate: number;
+    avgPriority: number;
+  }>;
+  tagTrends: Array<{
+    date: string;
+    tagName: string;
+    count: number;
+  }>;
+  tagStats: {
+    totalTags: number;
+    activeTags: number;
+    mostUsedTag: string;
+    leastUsedTag: string;
+    avgTasksPerTag: number;
+  };
+}
+
+export interface TimeRange {
+  start: Date;
+  end: Date;
+}
+
+export class TagAnalyticsService {
+  /**
+   * Calcule les métriques de distribution par tags
+   */
+  static async getTagDistributionMetrics(
+    timeRange?: TimeRange, 
+    sources?: string[]
+  ): Promise<TagDistributionMetrics> {
+    try {
+      const now = getToday();
+      const defaultStart = subtractDays(now, 30); // 30 jours
+      
+      const start = timeRange?.start || defaultStart;
+      const end = timeRange?.end || now;
+
+      // Récupérer toutes les tâches avec leurs tags
+      const dbTasks = await prisma.task.findMany({
+        where: {
+          createdAt: {
+            gte: start,
+            lte: end
+          }
+        },
+        include: {
+          taskTags: {
+            include: {
+              tag: true
+            }
+          }
+        }
+      });
+
+      // Récupérer aussi tous les tags pour avoir leurs couleurs
+      const allTags = await prisma.tag.findMany({
+        select: {
+          name: true,
+          color: true
+        }
+      });
+      
+      const tagColorMap = new Map(
+        allTags.map(tag => [tag.name, tag.color])
+      );
+
+      // Convertir en format Task
+      let tasks: Task[] = dbTasks.map(task => ({
+        id: task.id,
+        title: task.title,
+        description: task.description || undefined,
+        status: task.status as TaskStatus,
+        priority: task.priority as TaskPriority,
+        source: task.source as TaskSource,
+        sourceId: task.sourceId || undefined,
+        tags: task.taskTags.map(taskTag => taskTag.tag.name),
+        dueDate: task.dueDate || undefined,
+        completedAt: task.completedAt || undefined,
+        createdAt: task.createdAt,
+        updatedAt: task.updatedAt,
+        jiraProject: task.jiraProject || undefined,
+        jiraKey: task.jiraKey || undefined,
+        jiraType: task.jiraType || undefined,
+        assignee: task.assignee || undefined
+      }));
+
+      // Filtrer par sources si spécifié
+      if (sources && sources.length > 0) {
+        tasks = tasks.filter(task => sources.includes(task.source));
+      }
+
+      return {
+        tagDistribution: this.calculateTagDistribution(tasks, tagColorMap),
+        topTags: this.calculateTopTags(tasks, tagColorMap),
+        tagTrends: this.calculateTagTrends(tasks),
+        tagStats: this.calculateTagStats(tasks)
+      };
+    } catch (error) {
+      console.error('Erreur lors du calcul des métriques de tags:', error);
+      throw new Error('Impossible de calculer les métriques de distribution par tags');
+    }
+  }
+
+  /**
+   * Calcule la distribution des tags
+   */
+  private static calculateTagDistribution(tasks: Task[], tagColorMap: Map<string, string>) {
+    const tagCounts = new Map<string, { color: string; tasks: Task[] }>();
+    
+    // Compter les tâches par tag
+    tasks.forEach(task => {
+      task.tags.forEach(tagName => {
+        if (!tagCounts.has(tagName)) {
+          const tagColor = getTagColor(tagName, tagColorMap.get(tagName));
+          tagCounts.set(tagName, { color: tagColor, tasks: [] });
+        }
+        tagCounts.get(tagName)!.tasks.push(task);
+      });
+    });
+
+    const totalTasks = tasks.length;
+    
+    return Array.from(tagCounts.entries())
+      .map(([tagName, data]) => ({
+        tagName,
+        tagColor: data.color,
+        count: data.tasks.length,
+        percentage: totalTasks > 0 ? (data.tasks.length / totalTasks) * 100 : 0,
+        tasks: data.tasks.map(task => ({
+          id: task.id,
+          title: task.title,
+          status: task.status,
+          priority: task.priority
+        }))
+      }))
+      .sort((a, b) => b.count - a.count);
+  }
+
+  /**
+   * Calcule les tags les plus utilisés avec métriques
+   */
+  private static calculateTopTags(tasks: Task[], tagColorMap: Map<string, string>) {
+    const tagMetrics = new Map<string, {
+      color: string;
+      totalTasks: number;
+      completedTasks: number;
+      prioritySum: number;
+      priorityCount: number;
+    }>();
+
+    // Calculer les métriques par tag
+    tasks.forEach(task => {
+      task.tags.forEach(tagName => {
+        if (!tagMetrics.has(tagName)) {
+          const tagColor = getTagColor(tagName, tagColorMap.get(tagName));
+          tagMetrics.set(tagName, {
+            color: tagColor,
+            totalTasks: 0,
+            completedTasks: 0,
+            prioritySum: 0,
+            priorityCount: 0
+          });
+        }
+        
+        const metrics = tagMetrics.get(tagName)!;
+        metrics.totalTasks++;
+        
+        if (task.status === 'done') {
+          metrics.completedTasks++;
+        }
+        
+        // Convertir la priorité en nombre pour le calcul de moyenne
+        const priorityValue = task.priority === 'high' ? 3 : 
+                            task.priority === 'medium' ? 2 : 1;
+        metrics.prioritySum += priorityValue;
+        metrics.priorityCount++;
+      });
+    });
+
+    return Array.from(tagMetrics.entries())
+      .map(([tagName, metrics]) => ({
+        tagName,
+        tagColor: metrics.color,
+        usage: metrics.totalTasks,
+        completionRate: metrics.totalTasks > 0 ? 
+          (metrics.completedTasks / metrics.totalTasks) * 100 : 0,
+        avgPriority: metrics.priorityCount > 0 ? 
+          metrics.prioritySum / metrics.priorityCount : 0
+      }))
+      .sort((a, b) => b.usage - a.usage)
+      .slice(0, 10); // Top 10
+  }
+
+  /**
+   * Calcule les tendances des tags dans le temps
+   */
+  private static calculateTagTrends(tasks: Task[]) {
+    const trends = new Map<string, Map<string, number>>();
+    
+    // Grouper par jour et par tag
+    tasks.forEach(task => {
+      const day = task.createdAt.toISOString().split('T')[0];
+      task.tags.forEach(tagName => {
+        if (!trends.has(tagName)) {
+          trends.set(tagName, new Map());
+        }
+        const dayMap = trends.get(tagName)!;
+        dayMap.set(day, (dayMap.get(day) || 0) + 1);
+      });
+    });
+
+    // Convertir en format pour le graphique
+    const result: Array<{ date: string; tagName: string; count: number }> = [];
+    trends.forEach((dayMap, tagName) => {
+      dayMap.forEach((count, date) => {
+        result.push({ date, tagName, count });
+      });
+    });
+
+    return result.sort((a, b) => a.date.localeCompare(b.date));
+  }
+
+  /**
+   * Calcule les statistiques générales des tags
+   */
+  private static calculateTagStats(tasks: Task[]) {
+    const allTags = new Set<string>();
+    const tagUsage = new Map<string, number>();
+    
+    tasks.forEach(task => {
+      task.tags.forEach(tagName => {
+        allTags.add(tagName);
+        tagUsage.set(tagName, (tagUsage.get(tagName) || 0) + 1);
+      });
+    });
+
+    const usageValues = Array.from(tagUsage.values());
+    const mostUsedTag = Array.from(tagUsage.entries())
+      .sort((a, b) => b[1] - a[1])[0]?.[0] || 'Aucun';
+    const leastUsedTag = Array.from(tagUsage.entries())
+      .sort((a, b) => a[1] - b[1])[0]?.[0] || 'Aucun';
+
+    return {
+      totalTags: allTags.size,
+      activeTags: Array.from(tagUsage.values()).filter(count => count > 0).length,
+      mostUsedTag,
+      leastUsedTag,
+      avgTasksPerTag: allTags.size > 0 ? 
+        usageValues.reduce((sum, count) => sum + count, 0) / allTags.size : 0
+    };
+  }
+}

src/services/task-management/tasks.ts

@@ -2,6 +2,7 @@ import { prisma } from '@/services/core/database';
 import { Task, TaskStatus, TaskPriority, TaskSource, BusinessError, DailyCheckbox, DailyCheckboxType, Tag } from '@/lib/types';
 import { Prisma } from '@prisma/client';
 import { getToday } from '@/lib/date-utils';
+import { generateTagColor } from '@/lib/tag-colors';
 
 /**
  * Service pour la gestion des tâches (version standalone)
@@ -336,20 +337,7 @@ export class TasksService {
    * Génère une couleur pour un tag basée sur son nom
    */
   private generateTagColor(tagName: string): string {
-    const colors = [
+    return generateTagColor(tagName);
-      '#ef4444', '#f97316', '#f59e0b', '#eab308',
-      '#84cc16', '#22c55e', '#10b981', '#14b8a6',
-      '#06b6d4', '#0ea5e9', '#3b82f6', '#6366f1',
-      '#8b5cf6', '#a855f7', '#d946ef', '#ec4899'
-    ];
-    
-    // Hash simple du nom pour choisir une couleur
-    let hash = 0;
-    for (let i = 0; i < tagName.length; i++) {
-      hash = tagName.charCodeAt(i) + ((hash << 5) - hash);
-    }
-    
-    return colors[Math.abs(hash) % colors.length];
   }
 
   /**