feat: add transaction deduplication feature and enhance filtering options in settings and transactions pages

app/statistics/page.tsx

@@ -23,6 +23,7 @@ import { CategoryFilterCombobox } from "@/components/ui/category-filter-combobox
 import { Card, CardContent } from "@/components/ui/card";
 import { Badge } from "@/components/ui/badge";
 import { CategoryIcon } from "@/components/ui/category-icon";
+import { Checkbox } from "@/components/ui/checkbox";
 import { Filter, X, Wallet, CircleSlash, Calendar } from "lucide-react";
 import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover";
 import { Calendar as CalendarComponent } from "@/components/ui/calendar";
@@ -38,6 +39,7 @@ export default function StatisticsPage() {
   const [period, setPeriod] = useState<Period>("6months");
   const [selectedAccounts, setSelectedAccounts] = useState<string[]>(["all"]);
   const [selectedCategories, setSelectedCategories] = useState<string[]>(["all"]);
+  const [excludeInternalTransfers, setExcludeInternalTransfers] = useState(true);
   const [customStartDate, setCustomStartDate] = useState<Date | undefined>(undefined);
   const [customEndDate, setCustomEndDate] = useState<Date | undefined>(undefined);
   const [isCustomDatePickerOpen, setIsCustomDatePickerOpen] = useState(false);
@@ -69,6 +71,14 @@ export default function StatisticsPage() {
     return undefined;
   }, [period, customEndDate]);
 
+  // Find "Virement interne" category
+  const internalTransferCategory = useMemo(() => {
+    if (!data) return null;
+    return data.categories.find(
+      (c) => c.name.toLowerCase() === "virement interne"
+    );
+  }, [data]);
+
   // Transactions filtered for account filter (by categories, period - not accounts)
   const transactionsForAccountFilter = useMemo(() => {
     if (!data) return [];
@@ -98,8 +108,14 @@ export default function StatisticsPage() {
         }
       }
       return true;
+    }).filter((t) => {
+      // Exclude "Virement interne" category if checkbox is checked
+      if (excludeInternalTransfers && internalTransferCategory) {
+        return t.categoryId !== internalTransferCategory.id;
+      }
+      return true;
     });
-  }, [data, startDate, endDate, selectedCategories]);
+  }, [data, startDate, endDate, selectedCategories, excludeInternalTransfers, internalTransferCategory]);
 
   // Transactions filtered for category filter (by accounts, period - not categories)
   const transactionsForCategoryFilter = useMemo(() => {
@@ -126,8 +142,14 @@ export default function StatisticsPage() {
         return selectedAccounts.includes(t.accountId);
       }
       return true;
+    }).filter((t) => {
+      // Exclude "Virement interne" category if checkbox is checked
+      if (excludeInternalTransfers && internalTransferCategory) {
+        return t.categoryId !== internalTransferCategory.id;
+      }
+      return true;
     });
-  }, [data, startDate, endDate, selectedAccounts]);
+  }, [data, startDate, endDate, selectedAccounts, excludeInternalTransfers, internalTransferCategory]);
 
   const stats = useMemo(() => {
     if (!data) return null;
@@ -163,6 +185,13 @@ export default function StatisticsPage() {
       }
     }
 
+    // Exclude "Virement interne" category if checkbox is checked
+    if (excludeInternalTransfers && internalTransferCategory) {
+      transactions = transactions.filter(
+        (t) => t.categoryId !== internalTransferCategory.id
+      );
+    }
+
     // Monthly breakdown
     const monthlyData = new Map<string, { income: number; expenses: number }>();
     transactions.forEach((t) => {
@@ -211,10 +240,20 @@ export default function StatisticsPage() {
       .sort((a, b) => b.value - a.value)
       .slice(0, 8);
 
-    // Top expenses
-    const topExpenses = transactions
+    // Top expenses - deduplicate by ID and sort by amount (most negative first)
+    const uniqueTransactions = Array.from(
+      new Map(transactions.map((t) => [t.id, t])).values()
+    );
+    const topExpenses = uniqueTransactions
       .filter((t) => t.amount < 0)
-      .sort((a, b) => a.amount - b.amount)
+      .sort((a, b) => {
+        // Sort by amount (most negative first)
+        if (a.amount !== b.amount) {
+          return a.amount - b.amount;
+        }
+        // If same amount, sort by date (most recent first) for stable sorting
+        return new Date(b.date).getTime() - new Date(a.date).getTime();
+      })
       .slice(0, 5);
 
     // Summary
@@ -259,6 +298,10 @@ export default function StatisticsPage() {
               return false;
           }
         }
+        // Exclude "Virement interne" category if checkbox is checked
+        if (excludeInternalTransfers && internalTransferCategory) {
+          if (t.categoryId === internalTransferCategory.id) return false;
+        }
         // Only transactions before startDate
         const transactionDate = new Date(t.date);
         return transactionDate < startDate;
@@ -308,6 +351,10 @@ export default function StatisticsPage() {
                 return false;
             }
           }
+          // Exclude "Virement interne" category if checkbox is checked
+          if (excludeInternalTransfers && internalTransferCategory) {
+            if (t.categoryId === internalTransferCategory.id) return false;
+          }
           const transactionDate = new Date(t.date);
           return transactionDate < startDate;
         })
@@ -373,7 +420,7 @@ export default function StatisticsPage() {
       perAccountBalanceData,
       transactionCount: transactions.length,
     };
-  }, [data, startDate, endDate, selectedAccounts, selectedCategories]);
+  }, [data, startDate, endDate, selectedAccounts, selectedCategories, excludeInternalTransfers, internalTransferCategory]);
 
   const formatCurrency = (amount: number) => {
     return new Intl.NumberFormat("fr-FR", {
@@ -517,6 +564,22 @@ export default function StatisticsPage() {
                 </PopoverContent>
               </Popover>
             )}
+
+            {internalTransferCategory && (
+              <div className="flex items-center gap-2 px-3 py-2 border border-border rounded-md bg-[var(--card)]">
+                <Checkbox
+                  id="exclude-internal-transfers"
+                  checked={excludeInternalTransfers}
+                  onCheckedChange={(checked) => setExcludeInternalTransfers(checked === true)}
+                />
+                <label
+                  htmlFor="exclude-internal-transfers"
+                  className="text-sm font-medium cursor-pointer select-none"
+                >
+                  Exclure Virement interne
+                </label>
+              </div>
+            )}
           </div>
 
           <ActiveFilters