Fix audit findings: budget editing, dead code, logging, multi-currency

- Add budget editing: updateBudget() API, edit button on budget cards,
  BudgetFormModal adapted for create/update (category locked on edit)
- Remove permanently-broken POST /auth/totp/verify stub and its unused
  TOTPVerifyRequest schema
- Wire getHoldingTransactions() to AssetDetail page — transaction history
  table now shows above the candlestick chart, sorted newest-first
- Fix multi-currency net worth in account_service: account balances are
  now converted to base_currency via ExchangeRate table before summing
- Replace silent bare pass exception handlers with logger.warning() in
  transactions.py (OCR/AI pipeline) and price_feed_service.py (search)
  — ValueError in date/number regex parsing left silent (control flow)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/api/v1/auth.py

@@ -19,7 +19,7 @@ from app.schemas.auth import (
     TOTPChallengeResponse,
     TOTPLoginRequest,
     TOTPSetupResponse,
-    TOTPVerifyRequest,
+
     TokenResponse,
 )
 from app.services.auth_service import (
@@ -297,20 +297,6 @@ async def totp_setup(
     return TOTPSetupResponse(secret=secret, qr_code_png_b64=qr_b64, backup_codes=backup_codes)
 
 
-@router.post("/totp/verify", status_code=200)
-async def totp_verify(
-    body: TOTPVerifyRequest,
-    request: Request,
-    db: AsyncSession = Depends(get_db),
-    user=Depends(get_current_user),
-):
-    # Secret must be passed back from setup — here we expect it stored temporarily in body
-    # In practice the client stores it until verification; it's never persisted until verified
-    # This endpoint receives the secret + verification code
-    # For simplicity we accept: {"secret": "...", "code": "..."}
-    # Redefine body inline:
-    raise HTTPException(status_code=400, detail="Use /totp/enable endpoint with secret and code")
-
 
 @router.post("/totp/enable", status_code=200)
 async def totp_enable(

backend/app/api/v1/transactions.py

@@ -1,11 +1,14 @@
 import csv
 import io
+import logging
 import mimetypes
 import os
 import uuid
 from pathlib import Path
 from typing import Annotated
 
+logger = logging.getLogger(__name__)
+
 from fastapi import APIRouter, Depends, File, Form, HTTPException, Query, UploadFile
 from fastapi.responses import FileResponse
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -265,8 +268,8 @@ async def delete_attachment(
     path = Path(settings.upload_dir) / str(user.id) / ref["stored_name"]
     try:
         path.unlink(missing_ok=True)
-    except OSError:
-        pass
+    except OSError as e:
+        logger.warning("Could not delete attachment file %s: %s", path, e)
 
     new_refs = [r for r in refs if r["id"] != attachment_id]
     await db.execute(
@@ -307,8 +310,8 @@ def _extract_ocr_text(file_bytes: bytes, mime_type: str) -> str:
             text = "\n".join(pages_text).strip()
             if text:
                 return text
-        except Exception:
-            pass
+        except Exception as e:
+            logger.warning("pdfplumber text extraction failed: %s", e)
         # Scanned PDF — convert first page to image then OCR
         try:
             from pdf2image import convert_from_bytes
@@ -316,8 +319,8 @@ def _extract_ocr_text(file_bytes: bytes, mime_type: str) -> str:
             images = convert_from_bytes(file_bytes, first_page=1, last_page=1, dpi=200)
             if images:
                 return pytesseract.image_to_string(images[0])
-        except Exception:
-            pass
+        except Exception as e:
+            logger.warning("pdf2image/tesseract OCR failed: %s", e)
         return ""
     else:
         import io
@@ -326,7 +329,8 @@ def _extract_ocr_text(file_bytes: bytes, mime_type: str) -> str:
         try:
             img = Image.open(io.BytesIO(file_bytes))
             return pytesseract.image_to_string(img)
-        except Exception:
+        except Exception as e:
+            logger.warning("Image OCR failed: %s", e)
             return ""
 
 
@@ -488,11 +492,10 @@ async def _call_ai_parse(file_bytes: bytes, mime_type: str, user_row) -> dict:
                         "ocr_text":    ocr_text,
                     }
                 except json.JSONDecodeError:
-                    # AI returned something non-JSON — fall through to rules, keep raw for debug
-                    pass
+                    logger.warning("AI returned non-JSON response, falling back to rule-based parser")
 
-        except (httpx.HTTPStatusError, httpx.RequestError):
-            pass  # fall through to rule-based
+        except (httpx.HTTPStatusError, httpx.RequestError) as e:
+            logger.warning("AI API request failed (%s), falling back to rule-based parser", type(e).__name__)
 
     # Step 3: rule-based fallback (also used when AI is not configured)
     if ocr_text.strip():

backend/app/schemas/auth.py

@@ -48,9 +48,6 @@ class TOTPSetupResponse(BaseModel):
     backup_codes: list[str]
 
 
-class TOTPVerifyRequest(BaseModel):
-    code: str
-
 
 class TOTPEnableRequest(BaseModel):
     secret: str

backend/app/services/account_service.py

@@ -9,6 +9,7 @@ from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.core.security import encrypt_field, decrypt_field
 from app.db.models.account import Account
+from app.db.models.currency import ExchangeRate
 from app.db.models.transaction import Transaction
 from app.schemas.account import AccountCreate, AccountUpdate
 
@@ -168,6 +169,19 @@ async def recalculate_balance(db: AsyncSession, account_id: uuid.UUID) -> None:
     await db.flush()
 
 
+async def _fx_rate(db: AsyncSession, from_currency: str, to_currency: str) -> Decimal:
+    if from_currency == to_currency:
+        return Decimal("1")
+    result = await db.execute(
+        select(ExchangeRate)
+        .where(ExchangeRate.base_currency == from_currency, ExchangeRate.quote_currency == to_currency)
+        .order_by(ExchangeRate.fetched_at.desc())
+        .limit(1)
+    )
+    er = result.scalar_one_or_none()
+    return er.rate if er else Decimal("1")
+
+
 async def get_net_worth(db: AsyncSession, user_id: uuid.UUID, base_currency: str) -> dict:
     accounts = await db.execute(
         select(Account).where(
@@ -180,8 +194,11 @@ async def get_net_worth(db: AsyncSession, user_id: uuid.UUID, base_currency: str
     total_liabilities = Decimal("0")
 
     for account in accounts.scalars():
-        # TODO Phase 3: convert to base_currency via FX rates
-        bal = account.current_balance
+        bal = account.current_balance or Decimal("0")
+        acct_currency = account.currency or base_currency
+        if acct_currency != base_currency:
+            rate = await _fx_rate(db, acct_currency, base_currency)
+            bal = bal * rate
         if account.type in LIABILITY_TYPES:
             total_liabilities += abs(bal)
         else:

backend/app/services/price_feed_service.py

@@ -118,6 +118,6 @@ def search_yahoo(query: str) -> list[dict]:
                 "data_source_id": None,
             })
         return out
-    except Exception:
-        pass
+    except Exception as exc:
+        logger.warning("yahoo_search_failed", query=query, error=str(exc))
     return []

frontend/src/api/budgets.ts

@@ -60,6 +60,21 @@ export async function createBudget(data: BudgetCreate): Promise<Budget> {
   return r.data;
 }
 
+export interface BudgetUpdate {
+  name?: string;
+  amount?: number;
+  period?: "weekly" | "monthly" | "quarterly" | "yearly";
+  end_date?: string | null;
+  rollover?: boolean;
+  alert_threshold?: number;
+  is_active?: boolean;
+}
+
+export async function updateBudget(id: string, data: BudgetUpdate): Promise<Budget> {
+  const r = await api.put(`/budgets/${id}`, data);
+  return r.data;
+}
+
 export async function deleteBudget(id: string): Promise<void> {
   await api.delete(`/budgets/${id}`);
 }

frontend/src/pages/budgets/BudgetFormModal.tsx

@@ -1,6 +1,6 @@
 import { useState } from "react";
 import { X } from "lucide-react";
-import { BudgetCreate } from "@/api/budgets";
+import type { Budget, BudgetCreate } from "@/api/budgets";
 import { format } from "date-fns";
 
 interface Category {
@@ -14,22 +14,24 @@ interface Props {
   onClose: () => void;
   onSubmit: (data: BudgetCreate) => void;
   isLoading: boolean;
+  budget?: Budget;
 }
 
-export default function BudgetFormModal({ categories, onClose, onSubmit, isLoading }: Props) {
+export default function BudgetFormModal({ categories, onClose, onSubmit, isLoading, budget }: Props) {
   const today = format(new Date(), "yyyy-MM-dd");
   const [form, setForm] = useState<BudgetCreate>({
-    category_id: "",
-    name: "",
-    amount: 0,
-    currency: "GBP",
-    period: "monthly",
-    start_date: today,
-    end_date: null,
-    rollover: false,
-    alert_threshold: 80,
+    category_id: budget?.category_id ?? "",
+    name: budget?.name ?? "",
+    amount: budget?.amount ?? 0,
+    currency: budget?.currency ?? "GBP",
+    period: (budget?.period as BudgetCreate["period"]) ?? "monthly",
+    start_date: budget?.start_date ?? today,
+    end_date: budget?.end_date ?? null,
+    rollover: budget?.rollover ?? false,
+    alert_threshold: budget?.alert_threshold ?? 80,
   });
 
+  const isEdit = !!budget;
   const expenseCategories = categories.filter((c) => c.type === "expense" || c.type === "system");
 
   function set<K extends keyof BudgetCreate>(key: K, value: BudgetCreate[K]) {
@@ -46,7 +48,7 @@ export default function BudgetFormModal({ categories, onClose, onSubmit, isLoadi
     <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50 backdrop-blur-sm p-4">
       <div className="bg-card border border-border rounded-2xl w-full max-w-md shadow-xl">
         <div className="flex items-center justify-between p-5 border-b border-border">
-          <h2 className="font-semibold text-lg">New Budget</h2>
+          <h2 className="font-semibold text-lg">{isEdit ? "Edit Budget" : "New Budget"}</h2>
           <button onClick={onClose} className="p-1.5 rounded-lg hover:bg-secondary text-muted-foreground">
             <X className="w-4 h-4" />
           </button>
@@ -71,12 +73,14 @@ export default function BudgetFormModal({ categories, onClose, onSubmit, isLoadi
               onChange={(e) => set("category_id", e.target.value)}
               className="w-full rounded-md border border-input bg-background px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-ring"
               required
+              disabled={isEdit}
             >
               <option value="">Select category...</option>
               {expenseCategories.map((c) => (
                 <option key={c.id} value={c.id}>{c.name}</option>
               ))}
             </select>
+            {isEdit && <p className="text-xs text-muted-foreground mt-1">Category cannot be changed after creation.</p>}
           </div>
 
           <div className="grid grid-cols-2 gap-3">
@@ -154,7 +158,7 @@ export default function BudgetFormModal({ categories, onClose, onSubmit, isLoadi
               disabled={isLoading}
               className="flex-1 py-2.5 rounded-lg bg-primary text-primary-foreground text-sm font-medium hover:bg-primary/90 disabled:opacity-50 transition-colors"
             >
-              {isLoading ? "Creating..." : "Create Budget"}
+              {isLoading ? (isEdit ? "Saving..." : "Creating...") : (isEdit ? "Save changes" : "Create Budget")}
             </button>
           </div>
         </form>

frontend/src/pages/budgets/BudgetPage.tsx

@@ -1,10 +1,10 @@
 import { useState } from "react";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
-import { getBudgetSummary, createBudget, deleteBudget } from "@/api/budgets";
+import { getBudgets, getBudgetSummary, createBudget, updateBudget, deleteBudget, type Budget } from "@/api/budgets";
 import { getCategories } from "@/api/transactions";
 import { formatCurrency } from "@/utils/currency";
 import { cn } from "@/utils/cn";
-import { Plus, Trash2, AlertTriangle, CheckCircle } from "lucide-react";
+import { Plus, Trash2, Pencil, AlertTriangle, CheckCircle } from "lucide-react";
 import BudgetFormModal from "./BudgetFormModal";
 
 function RadialGauge({ percent, size = 80 }: { percent: number; size?: number }) {
@@ -55,6 +55,7 @@ function RadialGauge({ percent, size = 80 }: { percent: number; size?: number })
 export default function BudgetPage() {
   const qc = useQueryClient();
   const [showForm, setShowForm] = useState(false);
+  const [editing, setEditing] = useState<Budget | null>(null);
 
   const { data: summary = [], isLoading } = useQuery({
     queryKey: ["budget-summary"],
@@ -62,23 +63,32 @@ export default function BudgetPage() {
     refetchInterval: 60_000,
   });
 
+  const { data: budgets = [] } = useQuery({
+    queryKey: ["budgets"],
+    queryFn: () => getBudgets(false),
+  });
+
   const { data: categories = [] } = useQuery({ queryKey: ["categories"], queryFn: getCategories });
 
+  const invalidate = () => {
+    qc.invalidateQueries({ queryKey: ["budget-summary"] });
+    qc.invalidateQueries({ queryKey: ["budgets"] });
+  };
+
   const createMutation = useMutation({
     mutationFn: createBudget,
-    onSuccess: () => {
-      qc.invalidateQueries({ queryKey: ["budget-summary"] });
-      qc.invalidateQueries({ queryKey: ["budgets"] });
-      setShowForm(false);
-    },
+    onSuccess: () => { invalidate(); setShowForm(false); },
+  });
+
+  const updateMutation = useMutation({
+    mutationFn: ({ id, data }: { id: string; data: Parameters<typeof updateBudget>[1] }) =>
+      updateBudget(id, data),
+    onSuccess: () => { invalidate(); setEditing(null); },
   });
 
   const deleteMutation = useMutation({
     mutationFn: deleteBudget,
-    onSuccess: () => {
-      qc.invalidateQueries({ queryKey: ["budget-summary"] });
-      qc.invalidateQueries({ queryKey: ["budgets"] });
-    },
+    onSuccess: invalidate,
   });
 
   const overBudget = summary.filter((s) => s.is_over_budget).length;
@@ -133,12 +143,25 @@ export default function BudgetPage() {
                   : "border-border"
               )}
             >
+              <div className="absolute top-3 right-3 flex gap-1 opacity-0 group-hover:opacity-100 transition-all">
+                <button
+                  onClick={() => {
+                    const b = budgets.find((b) => b.id === item.budget_id);
+                    if (b) setEditing(b);
+                  }}
+                  className="p-1 rounded text-muted-foreground hover:text-foreground hover:bg-secondary"
+                  title="Edit budget"
+                >
+                  <Pencil className="w-3.5 h-3.5" />
+                </button>
                 <button
                   onClick={() => deleteMutation.mutate(item.budget_id)}
-                className="absolute top-3 right-3 p-1 rounded text-muted-foreground hover:text-destructive opacity-0 group-hover:opacity-100 transition-all"
+                  className="p-1 rounded text-muted-foreground hover:text-destructive hover:bg-destructive/10"
+                  title="Delete budget"
                 >
                   <Trash2 className="w-3.5 h-3.5" />
                 </button>
+              </div>
 
               <div className="flex items-start gap-4">
                 <RadialGauge percent={Number(item.percent_used)} />
@@ -192,6 +215,16 @@ export default function BudgetPage() {
           isLoading={createMutation.isPending}
         />
       )}
+
+      {editing && (
+        <BudgetFormModal
+          categories={categories}
+          budget={editing}
+          onClose={() => setEditing(null)}
+          onSubmit={(data) => updateMutation.mutate({ id: editing.id, data })}
+          isLoading={updateMutation.isPending}
+        />
+      )}
     </div>
   );
 }

frontend/src/pages/investments/AssetDetail.tsx

@@ -1,6 +1,6 @@
 import { useParams, Link } from "react-router-dom";
 import { useQuery } from "@tanstack/react-query";
-import { getPriceHistory, getPortfolio } from "@/api/investments";
+import { getPriceHistory, getPortfolio, getHoldingTransactions } from "@/api/investments";
 import { formatCurrency } from "@/utils/currency";
 import { useUiStore } from "@/store/uiStore";
 import { cn } from "@/utils/cn";
@@ -20,6 +20,12 @@ export default function AssetDetail() {
     enabled: !!assetId,
   });
 
+  const { data: transactions = [] } = useQuery({
+    queryKey: ["holding-transactions", holding?.id],
+    queryFn: () => getHoldingTransactions(holding!.id),
+    enabled: !!holding?.id,
+  });
+
   const dates = prices.map(p => p.date);
   const opens = prices.map(p => p.open ?? p.close);
   const highs = prices.map(p => p.high ?? p.close);
@@ -73,6 +79,62 @@ export default function AssetDetail() {
         </div>
       )}
 
+      {/* Transaction history */}
+      {holding && (
+        <div className="bg-card border border-border rounded-xl overflow-hidden">
+          <div className="px-4 py-3 border-b border-border">
+            <p className="text-sm font-medium">Transaction History</p>
+          </div>
+          {transactions.length === 0 ? (
+            <p className="text-sm text-muted-foreground text-center py-8">No transactions recorded</p>
+          ) : (
+            <table className="w-full text-sm">
+              <thead>
+                <tr className="text-xs text-muted-foreground uppercase tracking-wider border-b border-border">
+                  <th className="text-left px-4 py-2">Date</th>
+                  <th className="text-left px-4 py-2">Type</th>
+                  <th className="text-right px-4 py-2">Quantity</th>
+                  <th className="text-right px-4 py-2">Price</th>
+                  <th className="text-right px-4 py-2 hidden sm:table-cell">Fees</th>
+                  <th className="text-right px-4 py-2">Total</th>
+                </tr>
+              </thead>
+              <tbody>
+                {[...transactions].sort((a, b) => b.date.localeCompare(a.date)).map((t) => {
+                  const isBuy = t.type === "buy" || t.type === "transfer_in";
+                  const isSell = t.type === "sell" || t.type === "transfer_out";
+                  return (
+                    <tr key={t.id} className="border-b border-border/50 last:border-0 hover:bg-secondary/20 transition-colors">
+                      <td className="px-4 py-2.5 tabular-nums text-muted-foreground">{t.date}</td>
+                      <td className="px-4 py-2.5">
+                        <span className={cn(
+                          "inline-flex items-center px-2 py-0.5 rounded text-xs font-medium",
+                          isBuy ? "bg-success/15 text-success" :
+                          isSell ? "bg-destructive/15 text-destructive" :
+                          "bg-secondary text-muted-foreground"
+                        )}>
+                          {t.type.replace("_", " ")}
+                        </span>
+                      </td>
+                      <td className="px-4 py-2.5 text-right tabular-nums">{Number(t.quantity).toLocaleString()}</td>
+                      <td className="px-4 py-2.5 text-right tabular-nums">{formatCurrency(t.price, t.currency)}</td>
+                      <td className="px-4 py-2.5 text-right tabular-nums hidden sm:table-cell text-muted-foreground">
+                        {t.fees > 0 ? formatCurrency(t.fees, t.currency) : "—"}
+                      </td>
+                      <td className={cn("px-4 py-2.5 text-right tabular-nums font-medium",
+                        isBuy ? "text-destructive" : isSell ? "text-success" : ""
+                      )}>
+                        {isSell ? "+" : isBuy ? "-" : ""}{formatCurrency(t.total_amount, t.currency)}
+                      </td>
+                    </tr>
+                  );
+                })}
+              </tbody>
+            </table>
+          )}
+        </div>
+      )}
+
       {/* Candlestick chart */}
       <div className="bg-card border border-border rounded-xl p-4">
         <p className="text-sm font-medium mb-3">Price History (1 Year)</p>