Disposal

backend/app/main.py

@@ -73,6 +73,9 @@ class UserCreate(BaseModel):
     password: str
     role: Optional[str] = "user"  # admin, user, readonly
 
+class UserRoleUpdate(BaseModel):
+    role: str
+
 class PasswordChange(BaseModel):
     current_password: str
     new_password: str
@@ -297,6 +300,17 @@ class DispensingAllocationCreate(BaseModel):
     quantity: float
 
 
+class InventoryDisposeRequest(BaseModel):
+    drug_variant_id: int
+    quantity: Optional[float] = None
+    dispense_mode: str = "subunit"
+    dispense_source: str = "batch"
+    requested_pack_id: Optional[int] = None
+    requested_pack_count: Optional[float] = None
+    notes: Optional[str] = None
+    allocations: List[DispensingAllocationCreate] = []
+
+
 class DispensingCreate(BaseModel):
     drug_variant_id: int
     quantity: Optional[float] = None
@@ -876,6 +890,34 @@ def delete_user(user_id: int, db: Session = Depends(get_db), current_user: User
     db.commit()
     return {"message": "User deleted successfully"}
 
+@router.patch("/users/{user_id}/role", response_model=UserResponse)
+def update_user_role(user_id: int, role_data: UserRoleUpdate, db: Session = Depends(get_db), current_user: User = Depends(get_current_admin_user)):
+    """Update a user's role (admin only)"""
+    if current_user.id == user_id:
+        raise HTTPException(status_code=400, detail="Cannot change your own role")
+
+    valid_roles = ["admin", "user", "readonly"]
+    if role_data.role not in valid_roles:
+        raise HTTPException(status_code=400, detail=f"Invalid role. Must be one of: {', '.join(valid_roles)}")
+
+    user = db.query(User).filter(User.id == user_id).first()
+    if not user:
+        raise HTTPException(status_code=404, detail="User not found")
+
+    old_role = user.role
+    user.role = role_data.role
+    write_audit_log(
+        db,
+        action="user.role.update",
+        entity_type="user",
+        entity_id=user.id,
+        actor=current_user,
+        details={"username": user.username, "old_role": old_role, "new_role": user.role},
+    )
+    db.commit()
+    db.refresh(user)
+    return user
+
 @router.post("/auth/change-password")
 def change_own_password(password_data: PasswordChange, db: Session = Depends(get_db), current_user: User = Depends(get_current_user)):
     """Change current user's password"""
@@ -1620,6 +1662,110 @@ def dispense_drug(dispensing: DispensingCreate, db: Session = Depends(get_db), c
         "allocations": allocation_payload,
     }
 
+@router.post("/dispose")
+def dispose_inventory(payload: InventoryDisposeRequest, db: Session = Depends(get_db), current_user: User = Depends(get_current_admin_user)):
+    """Dispose selected inventory and reduce stock (admin only)"""
+    variant = db.query(DrugVariant).filter(DrugVariant.id == payload.drug_variant_id).first()
+    if not variant:
+        raise HTTPException(status_code=404, detail="Drug variant not found")
+
+    dispose_mode = (payload.dispense_mode or "subunit").strip().lower()
+    if dispose_mode not in {"subunit", "pack"}:
+        raise HTTPException(status_code=400, detail="dispose_mode must be either 'subunit' or 'pack'")
+
+    if dispose_mode == "pack":
+        if payload.requested_pack_id is None or payload.requested_pack_count is None:
+            raise HTTPException(status_code=400, detail="Pack disposal requires requested_pack_id and requested_pack_count")
+        if payload.requested_pack_count <= 0:
+            raise HTTPException(status_code=400, detail="Pack count must be greater than zero")
+        if abs(payload.requested_pack_count - round(payload.requested_pack_count)) > 1e-6:
+            raise HTTPException(status_code=400, detail="Whole-pack disposal requires an integer pack count")
+
+        resolved = resolve_pack_quantity(
+            db,
+            variant_id=variant.id,
+            quantity=None,
+            pack_id=payload.requested_pack_id,
+            pack_count=payload.requested_pack_count,
+        )
+    else:
+        if payload.quantity is None or payload.quantity <= 0:
+            raise HTTPException(status_code=400, detail="Quantity disposal requires quantity > 0")
+        resolved = resolve_pack_quantity(
+            db,
+            variant_id=variant.id,
+            quantity=payload.quantity,
+            pack_id=None,
+            pack_count=None,
+        )
+
+    dispose_qty = resolved["quantity"]
+    if variant.quantity < dispose_qty:
+        raise HTTPException(
+            status_code=400,
+            detail=f"Insufficient quantity. Available: {variant.quantity}, Requested: {dispose_qty}",
+        )
+
+    allocations = resolve_requested_allocations(
+        db,
+        variant_id=variant.id,
+        variant_quantity=variant.quantity,
+        requested_quantity=dispose_qty,
+        requested_allocations=payload.allocations,
+        dispense_mode=dispose_mode,
+        dispense_source=payload.dispense_source,
+        requested_pack_id=resolved["pack_id"],
+    )
+
+    selected_source = (payload.dispense_source or ("legacy" if not allocations else "batch")).strip().lower()
+    allocation_payload = []
+    disposed_at = datetime.utcnow()
+
+    for allocation in allocations:
+        batch = allocation["batch"]
+        qty = allocation["quantity"]
+        remaining_before = batch.quantity
+        batch.quantity -= qty
+        if batch.quantity <= 1e-6:
+            batch.quantity = 0
+            batch.disposed_at = disposed_at
+            batch.disposed_by_user_id = current_user.id
+            batch.disposed_quantity = remaining_before
+            batch.disposal_notes = payload.notes
+        recompute_batch_pack_state(batch)
+        allocation_payload.append({"batch_id": batch.id, "quantity": qty})
+
+    variant.quantity = max(0, variant.quantity - dispose_qty)
+
+    write_audit_log(
+        db,
+        action="inventory.dispose",
+        entity_type="drug_variant",
+        entity_id=variant.id,
+        actor=current_user,
+        details={
+            "drug_variant_id": variant.id,
+            "disposed_quantity": dispose_qty,
+            "dispose_mode": dispose_mode,
+            "dispose_source": selected_source,
+            "requested_pack_id": resolved["pack_id"],
+            "requested_pack_count": resolved["pack_count"],
+            "allocations": allocation_payload,
+            "notes": payload.notes,
+        },
+    )
+
+    db.commit()
+    db.refresh(variant)
+    return {
+        "message": "Inventory disposed successfully",
+        "drug_variant_id": variant.id,
+        "disposed_quantity": dispose_qty,
+        "dispose_mode": dispose_mode,
+        "dispose_source": selected_source,
+        "allocations": allocation_payload,
+    }
+
 @router.get("/dispense/history", response_model=List[DispensingResponse])
 def list_dispensings(skip: int = 0, limit: int = 100, db: Session = Depends(get_db), current_user: User = Depends(get_current_user)):
     """Get dispensing records (audit log)"""
@@ -2012,7 +2158,7 @@ def update_batch(batch_id: int, payload: BatchUpdate, db: Session = Depends(get_
 
 
 @router.post("/batches/{batch_id}/dispose", response_model=BatchResponse)
-def dispose_batch(batch_id: int, payload: BatchDisposeRequest, db: Session = Depends(get_db), current_user: User = Depends(get_current_non_readonly_user)):
+def dispose_batch(batch_id: int, payload: BatchDisposeRequest, db: Session = Depends(get_db), current_user: User = Depends(get_current_admin_user)):
     batch = db.query(Batch).filter(Batch.id == batch_id).first()
     if not batch:
         raise HTTPException(status_code=404, detail="Batch not found")

backend/requirements.txt

@@ -1,8 +1,8 @@
-fastapi==0.104.1
-uvicorn==0.24.0
-sqlalchemy==2.0.23
-pydantic==2.5.0
-python-multipart==0.0.6
-python-jose[cryptography]==3.3.0
+fastapi==0.137.2
+uvicorn==0.49.0
+sqlalchemy==2.0.51
+pydantic==2.13.4
+python-multipart==0.0.32
+python-jose[cryptography]==3.5.0
 passlib[argon2]==1.7.4
 paho-mqtt==1.6.1

frontend/app.js

@@ -15,6 +15,8 @@ let deliveryLineCounter = 0;
 let deliveryLocations = [];
 let currentDispenseBatches = [];
 let currentDispenseLegacyQuantity = 0;
+let currentDisposeBatches = [];
+let currentDisposeLegacyQuantity = 0;
 let _gtinMappingPendingRefresh = false;
 let _gtinMappingPendingVariantId = null;
 let _gtinMappingPendingRestore = null;  // { drugId, variantId, packId } — auto-select after reload
@@ -46,8 +48,10 @@ function resetDisposeBatchModal() {
     }
     const batchIdInput = document.getElementById('disposeBatchId');
     const batchNameInput = document.getElementById('disposeBatchName');
+    const stockSummaryInput = document.getElementById('disposeBatchStockSummary');
     if (batchIdInput) batchIdInput.value = '';
     if (batchNameInput) batchNameInput.value = '';
+    if (stockSummaryInput) stockSummaryInput.value = '';
 }
 
 function closeDisposeBatchModal() {
@@ -253,6 +257,7 @@ function setupEventListeners() {
     const variantForm = document.getElementById('variantForm');
     const editVariantForm = document.getElementById('editVariantForm');
     const dispenseForm = document.getElementById('dispenseForm');
+    const disposeInventoryForm = document.getElementById('disposeInventoryForm');
     const editForm = document.getElementById('editForm');
     const printNotesForm = document.getElementById('printNotesForm');
     const disposeBatchForm = document.getElementById('disposeBatchForm');
@@ -260,6 +265,7 @@ function setupEventListeners() {
     const addVariantModal = document.getElementById('addVariantModal');
     const editVariantModal = document.getElementById('editVariantModal');
     const dispenseModal = document.getElementById('dispenseModal');
+    const disposeInventoryModal = document.getElementById('disposeInventoryModal');
     const editModal = document.getElementById('editModal');
     const printNotesModal = document.getElementById('printNotesModal');
     const disposeBatchModal = document.getElementById('disposeBatchModal');
@@ -272,6 +278,7 @@ function setupEventListeners() {
     const cancelVariantBtn = document.getElementById('cancelVariantBtn');
     const cancelEditVariantBtn = document.getElementById('cancelEditVariantBtn');
     const cancelDispenseBtn = document.getElementById('cancelDispenseBtn');
+    const cancelDisposeInventoryBtn = document.getElementById('cancelDisposeInventoryBtn');
     const cancelEditBtn = document.getElementById('cancelEditBtn');
     const cancelDisposeBatchBtn = document.getElementById('cancelDisposeBatchBtn');
     const cancelBatchReceiveBtn = document.getElementById('cancelBatchReceiveBtn');
@@ -286,6 +293,8 @@ function setupEventListeners() {
     const editVariantUnitSelect = document.getElementById('editVariantUnit');
     const dispenseModeInputs = document.querySelectorAll('input[name="dispenseMode"]');
     const dispenseSourceInputs = document.querySelectorAll('input[name="dispenseSource"]');
+    const disposeModeInputs = document.querySelectorAll('input[name="disposeMode"]');
+    const disposeSourceInputs = document.querySelectorAll('input[name="disposeSource"]');
     const dispensePrintEnabled = document.getElementById('dispensePrintEnabled');
     const showAllBtn = document.getElementById('showAllBtn');
     const showLowStockBtn = document.getElementById('showLowStockBtn');
@@ -330,6 +339,7 @@ function setupEventListeners() {
     if (variantForm) variantForm.addEventListener('submit', handleAddVariant);
     if (editVariantForm) editVariantForm.addEventListener('submit', handleEditVariant);
     if (dispenseForm) dispenseForm.addEventListener('submit', handleDispenseDrug);
+    if (disposeInventoryForm) disposeInventoryForm.addEventListener('submit', handleDisposeInventory);
     if (editForm) editForm.addEventListener('submit', handleEditDrug);
     if (printNotesForm) printNotesForm.addEventListener('submit', handlePrintNotes);
     if (disposeBatchForm) disposeBatchForm.addEventListener('submit', handleDisposeBatch);
@@ -387,6 +397,11 @@ function setupEventListeners() {
         toggleDispensePrintFields();
         updateDispenseAllocationSummary();
     }));
+    disposeModeInputs.forEach(input => input.addEventListener('change', updateDisposeModeUi));
+    disposeSourceInputs.forEach(input => input.addEventListener('change', () => {
+        renderDisposeInventorySourceView();
+        updateDisposeAllocationSummary();
+    }));
     if (dispensePrintEnabled) {
         dispensePrintEnabled.addEventListener('change', toggleDispensePrintFields);
     }
@@ -404,6 +419,7 @@ function setupEventListeners() {
     if (cancelVariantBtn) cancelVariantBtn.addEventListener('click', () => closeModal(addVariantModal));
     if (cancelEditVariantBtn) cancelEditVariantBtn.addEventListener('click', () => closeModal(editVariantModal));
     if (cancelDispenseBtn) cancelDispenseBtn.addEventListener('click', () => closeModal(dispenseModal));
+    if (cancelDisposeInventoryBtn) cancelDisposeInventoryBtn.addEventListener('click', () => closeModal(disposeInventoryModal));
     if (cancelEditBtn) cancelEditBtn.addEventListener('click', closeEditModal);
     if (cancelDisposeBatchBtn) cancelDisposeBatchBtn.addEventListener('click', closeDisposeBatchModal);
     
@@ -537,6 +553,40 @@ function setupEventListeners() {
         }, { passive: false });
     }
 
+    const disposeQuantityInput = document.getElementById('disposeQuantity');
+    if (disposeQuantityInput) {
+        disposeQuantityInput.addEventListener('wheel', (event) => {
+            event.preventDefault();
+        }, { passive: false });
+
+        disposeQuantityInput.addEventListener('input', () => {
+            if (getSelectedDisposeMode() !== 'subunit') return;
+
+            const packSelect = document.getElementById('disposePackSelect');
+            const packCount = document.getElementById('disposePackCount');
+            const packPreview = document.getElementById('disposePackPreview');
+            const variantId = parseInt(document.getElementById('disposeDrugSelect')?.value || '', 10);
+            const variant = getVariantById(variantId);
+
+            if (packSelect) packSelect.value = '';
+            if (packCount) packCount.value = '';
+            if (packPreview && variant) {
+                packPreview.textContent = `Enter direct quantity in ${variant.unit}.`;
+            }
+
+            autoAllocateDisposeBatches();
+        });
+    }
+
+    const disposePackCountInput = document.getElementById('disposePackCount');
+    if (disposePackCountInput) {
+        disposePackCountInput.addEventListener('wheel', (event) => {
+            event.preventDefault();
+        }, { passive: false });
+
+        disposePackCountInput.addEventListener('input', updateDisposeQuantityFromPack);
+    }
+
     // Close modal when clicking outside
     window.addEventListener('click', (e) => {
         if (e.target.classList.contains('modal')) {
@@ -1016,7 +1066,7 @@ function isBatchExpired(batch) {
 
 function renderVariantInventoryDetails(variant, batches) {
     const activePacks = getActivePacksForVariant(variant);
-    const isReadOnly = currentUser?.role === 'readonly';
+    const isAdmin = currentUser?.role === 'admin';
     const sortedBatches = [...(batches || [])]
         .filter(batch => Number(batch.quantity) > 0)
         .sort((a, b) => new Date(a.expiry_date) - new Date(b.expiry_date));
@@ -1056,9 +1106,9 @@ function renderVariantInventoryDetails(variant, batches) {
                         <span style="${expiryStyles}">Expires ${formatDisplayDate(batch.expiry_date)}</span>
                     </div>
                     <div style="margin-top: 4px; color: #374151;">${escapeHtml(locationLabel)} | ${stocktakeLabel}</div>
-                    ${expired && !isReadOnly ? `
+                    ${expired && isAdmin ? `
                         <div style="margin-top: 8px; display: flex; justify-content: flex-end;">
-                            <button class="btn btn-danger btn-small" onclick="event.stopPropagation(); disposeBatch(${batch.id}, '${String(batch.batch_number).replace(/'/g, "\\'")}')">Dispose Expired Batch</button>
+                            <button class="btn btn-danger btn-small" onclick="event.stopPropagation(); disposeBatch(${batch.id}, '${String(batch.batch_number).replace(/'/g, "\\'")}', '${String(stocktakeLabel).replace(/'/g, "\\'")}')">Dispose Expired Batch</button>
                         </div>
                     ` : ''}
                 </div>
@@ -1082,19 +1132,21 @@ function renderVariantInventoryDetails(variant, batches) {
     `;
 }
 
-function disposeBatch(batchId, batchNumber) {
+function disposeBatch(batchId, batchNumber, stockSummary = '') {
     const modal = document.getElementById('disposeBatchModal');
     const batchIdInput = document.getElementById('disposeBatchId');
     const batchNameInput = document.getElementById('disposeBatchName');
+    const stockSummaryInput = document.getElementById('disposeBatchStockSummary');
     const notesInput = document.getElementById('disposeBatchNotes');
 
-    if (!modal || !batchIdInput || !batchNameInput || !notesInput) {
+    if (!modal || !batchIdInput || !batchNameInput || !stockSummaryInput || !notesInput) {
         showToast('Dispose batch modal is unavailable.', 'error');
         return;
     }
 
     batchIdInput.value = String(batchId);
     batchNameInput.value = batchNumber;
+    stockSummaryInput.value = stockSummary;
     notesInput.value = '';
     openModal(modal);
 }
@@ -1684,6 +1736,560 @@ function updateDispenseAllocationSummary() {
     summaryContent.innerHTML = `<span style="color: #d32f2f; font-weight: 600;">Reduce allocations by ${formatDisplayNumber(Math.abs(difference))} ${escapeHtml(unitLabel)} to match the requested total.</span>`;
 }
 
+function updateDisposeDrugSelect() {
+    const select = document.getElementById('disposeDrugSelect');
+    if (!select) return;
+
+    select.innerHTML = '<option value="">-- Select a drug variant --</option>';
+    allDrugs.forEach(drug => {
+        drug.variants.forEach(variant => {
+            const option = document.createElement('option');
+            option.value = variant.id;
+            option.textContent = `${drug.name} ${variant.strength} (${variant.quantity} ${variant.unit})`;
+            select.appendChild(option);
+        });
+    });
+
+    const packSelect = document.getElementById('disposePackSelect');
+    const packCount = document.getElementById('disposePackCount');
+    const packPreview = document.getElementById('disposePackPreview');
+    const quantityModeRadio = document.getElementById('disposeModeQuantity');
+    const batchSourceRadio = document.getElementById('disposeSourceBatch');
+    const legacySourceRadio = document.getElementById('disposeSourceLegacy');
+
+    if (packSelect) packSelect.innerHTML = '<option value="">-- Select pack --</option>';
+    if (packCount) packCount.value = '';
+    if (quantityModeRadio) quantityModeRadio.checked = true;
+    if (packPreview) packPreview.textContent = 'Select a pack and whole-number count.';
+    if (batchSourceRadio) batchSourceRadio.checked = true;
+    if (legacySourceRadio) legacySourceRadio.checked = false;
+
+    currentDisposeBatches = [];
+    currentDisposeLegacyQuantity = 0;
+    updateDisposeModeUi();
+}
+
+function getSelectedDisposeMode() {
+    return document.querySelector('input[name="disposeMode"]:checked')?.value || 'subunit';
+}
+
+function hasLegacyDisposeQuantity() {
+    return currentDisposeLegacyQuantity > 0;
+}
+
+function hasBatchDisposeStock() {
+    return currentDisposeBatches.length > 0;
+}
+
+function getSelectedDisposeSource() {
+    if (getSelectedDisposeMode() === 'pack') return 'batch';
+
+    const selected = document.querySelector('input[name="disposeSource"]:checked')?.value;
+    if (selected) return selected;
+    if (hasLegacyDisposeQuantity() && !hasBatchDisposeStock()) return 'legacy';
+    return 'batch';
+}
+
+function isLegacyDisposeSelected() {
+    return getSelectedDisposeMode() === 'subunit' && getSelectedDisposeSource() === 'legacy' && hasLegacyDisposeQuantity();
+}
+
+function updateDisposeSourceUi() {
+    const sourceGroup = document.getElementById('disposeSourceGroup');
+    const sourceHelp = document.getElementById('disposeSourceHelp');
+    const batchRadio = document.getElementById('disposeSourceBatch');
+    const legacyRadio = document.getElementById('disposeSourceLegacy');
+    const hasBatches = hasBatchDisposeStock();
+    const hasLegacy = hasLegacyDisposeQuantity();
+
+    if (!sourceGroup || !batchRadio || !legacyRadio) return;
+
+    if (getSelectedDisposeMode() === 'pack' || (!hasBatches && !hasLegacy)) {
+        sourceGroup.style.display = 'none';
+        batchRadio.checked = true;
+        batchRadio.disabled = !hasBatches;
+        legacyRadio.checked = false;
+        legacyRadio.disabled = true;
+        if (sourceHelp) sourceHelp.textContent = '';
+        return;
+    }
+
+    batchRadio.disabled = !hasBatches;
+    legacyRadio.disabled = !hasLegacy;
+
+    if (hasLegacy && !hasBatches) {
+        legacyRadio.checked = true;
+    } else if (!hasLegacy && hasBatches) {
+        batchRadio.checked = true;
+    } else if (!batchRadio.checked && !legacyRadio.checked) {
+        batchRadio.checked = true;
+    }
+
+    sourceGroup.style.display = hasLegacy ? '' : 'none';
+    if (sourceHelp) {
+        if (hasLegacy && hasBatches) {
+            sourceHelp.textContent = `Batch stock available alongside ${formatDisplayNumber(currentDisposeLegacyQuantity)} loose legacy units.`;
+        } else if (hasLegacy) {
+            sourceHelp.textContent = `Legacy loose stock available: ${formatDisplayNumber(currentDisposeLegacyQuantity)}.`;
+        } else {
+            sourceHelp.textContent = '';
+        }
+    }
+}
+
+function getDisposeRequestedQuantity() {
+    const quantity = parseFloat(document.getElementById('disposeQuantity')?.value || '');
+    return Number.isNaN(quantity) || quantity <= 0 ? 0 : quantity;
+}
+
+function getSelectedDisposePack() {
+    const variantId = parseInt(document.getElementById('disposeDrugSelect')?.value || '', 10);
+    const packId = parseInt(document.getElementById('disposePackSelect')?.value || '', 10);
+    const variant = getVariantById(variantId);
+    if (!variant || Number.isNaN(packId)) return null;
+    return getActivePacksForVariant(variant).find(pack => pack.id === packId) || null;
+}
+
+function getBatchAvailableDisposeQuantity(batch, mode = getSelectedDisposeMode(), selectedPack = getSelectedDisposePack()) {
+    if (mode !== 'pack') return Number(batch.quantity || 0);
+    if (!batchMatchesSelectedPack(batch, selectedPack)) return 0;
+    return Math.max(0, Math.floor(Number(batch.current_full_pack_count || 0))) * Number(selectedPack.pack_size_in_base_units || 0);
+}
+
+function getTotalAvailableDisposeQuantity(mode = getSelectedDisposeMode(), selectedPack = getSelectedDisposePack()) {
+    if (getSelectedDisposeSource() === 'legacy') {
+        return mode === 'pack' ? 0 : currentDisposeLegacyQuantity;
+    }
+    return currentDisposeBatches.reduce((sum, batch) => sum + getBatchAvailableDisposeQuantity(batch, mode, selectedPack), 0);
+}
+
+function getTotalAvailableDisposePackCount(selectedPack = getSelectedDisposePack()) {
+    if (getSelectedDisposeSource() === 'legacy' || !selectedPack) return 0;
+    return currentDisposeBatches.reduce((sum, batch) => {
+        if (!batchMatchesSelectedPack(batch, selectedPack)) return sum;
+        return sum + Math.max(0, Math.floor(Number(batch.current_full_pack_count || 0)));
+    }, 0);
+}
+
+function populateDisposePackSelect(variant) {
+    const packSelect = document.getElementById('disposePackSelect');
+    const packCount = document.getElementById('disposePackCount');
+    const packPreview = document.getElementById('disposePackPreview');
+    if (!packSelect) return;
+
+    const activePacks = getActivePacksForVariant(variant);
+    packSelect.innerHTML = '<option value="">-- Select pack --</option>';
+    activePacks.forEach(pack => {
+        const option = document.createElement('option');
+        option.value = String(pack.id);
+        option.textContent = `${packLabel(pack)} (${pack.pack_size_in_base_units} ${variant.unit})`;
+        packSelect.appendChild(option);
+    });
+
+    if (packCount) packCount.value = '';
+    if (activePacks.length > 0) packSelect.value = String(activePacks[0].id);
+    if (packPreview) {
+        packPreview.textContent = activePacks.length > 0
+            ? `Select a pack and whole-number count (${variant.unit} base unit).`
+            : 'No active packs for this variant.';
+    }
+    if (activePacks.length > 0) updateDisposeQuantityFromPack();
+}
+
+function updateDisposeModeUi() {
+    const mode = getSelectedDisposeMode();
+    const quantityGroup = document.getElementById('disposeQuantityGroup');
+    const packRow = document.getElementById('disposePackRow');
+    const quantityInput = document.getElementById('disposeQuantity');
+    const packSelect = document.getElementById('disposePackSelect');
+    const packCount = document.getElementById('disposePackCount');
+
+    if (quantityGroup) quantityGroup.style.display = mode === 'subunit' ? '' : 'none';
+    if (packRow) packRow.style.display = mode === 'pack' ? '' : 'none';
+    if (quantityInput) quantityInput.required = mode === 'subunit';
+    if (packSelect) packSelect.required = mode === 'pack';
+    if (packCount) packCount.required = mode === 'pack';
+
+    updateDisposeSourceUi();
+    renderDisposeInventorySourceView();
+}
+
+function updateDisposeQuantityFromPack() {
+    if (getSelectedDisposeMode() !== 'pack') return;
+
+    const variantId = parseInt(document.getElementById('disposeDrugSelect')?.value || '', 10);
+    const packId = parseInt(document.getElementById('disposePackSelect')?.value || '', 10);
+    const packCount = parseFloat(document.getElementById('disposePackCount')?.value || '');
+    const quantityInput = document.getElementById('disposeQuantity');
+    const preview = document.getElementById('disposePackPreview');
+    const variant = getVariantById(variantId);
+    if (!quantityInput || !preview || !variant) return;
+
+    const selectedPack = getActivePacksForVariant(variant).find(pack => pack.id === packId);
+    const totalAvailablePacks = selectedPack ? getTotalAvailableDisposePackCount(selectedPack) : 0;
+    if (selectedPack && !Number.isNaN(packCount) && packCount > 0) {
+        if (Math.abs(packCount - Math.round(packCount)) > 1e-6) {
+            preview.textContent = 'Whole-pack mode requires a whole-number pack count.';
+            return;
+        }
+        const quantity = packCount * selectedPack.pack_size_in_base_units;
+        quantityInput.value = String(quantity);
+        if (totalAvailablePacks <= 0) {
+            preview.textContent = `No full ${selectedPack.pack_unit_name} packs are currently available.`;
+        } else if (packCount > totalAvailablePacks) {
+            preview.textContent = `Only ${totalAvailablePacks} full ${selectedPack.pack_unit_name} pack${totalAvailablePacks === 1 ? '' : 's'} available.`;
+        } else {
+            preview.textContent = `${packCount} x ${selectedPack.pack_size_in_base_units} = ${quantity} ${variant.unit} | ${totalAvailablePacks} full pack${totalAvailablePacks === 1 ? '' : 's'} available`;
+        }
+        autoAllocateDisposeBatches();
+        return;
+    }
+
+    quantityInput.value = '';
+    preview.textContent = selectedPack
+        ? `${totalAvailablePacks} full ${selectedPack.pack_unit_name} pack${totalAvailablePacks === 1 ? '' : 's'} available.`
+        : 'Select a pack and whole-number count.';
+    autoAllocateDisposeBatches();
+}
+
+function renderDisposeBatchAllocationRows(activeBatches) {
+    const batchInfoContent = document.getElementById('disposeBatchInfoContent');
+    const variantId = parseInt(document.getElementById('disposeDrugSelect').value || '', 10);
+    const variant = getVariantById(variantId);
+    const unitLabel = variant?.unit || 'units';
+    if (!batchInfoContent) return;
+
+    if (!activeBatches.length) {
+        batchInfoContent.innerHTML = '<p style="color: #d32f2f; margin: 0;">No active batches available for this variant</p>';
+        return;
+    }
+
+    const mode = getSelectedDisposeMode();
+    const selectedPack = getSelectedDisposePack();
+
+    batchInfoContent.innerHTML = activeBatches.map((batch, index) => {
+        const expiryDate = new Date(batch.expiry_date);
+        const locationLabel = getBatchLocationLabel(batch);
+        const expiryLabel = formatDisplayDate(batch.expiry_date);
+        const today = new Date();
+        const daysToExpiry = Math.ceil((expiryDate - today) / (1000 * 60 * 60 * 24));
+        const statusColor = daysToExpiry <= 7 ? '#ff9800' : '#4caf50';
+        const expiryStatus = daysToExpiry <= 7 ? `${daysToExpiry}d left` : 'OK';
+        const availableFullPacks = batchMatchesSelectedPack(batch, selectedPack)
+            ? Math.max(0, Math.floor(Number(batch.current_full_pack_count || 0)))
+            : 0;
+        const allocationLabel = mode === 'pack' ? 'Dispose Packs' : 'Dispose';
+        const allocationMax = mode === 'pack' ? availableFullPacks : getBatchAvailableDisposeQuantity(batch, mode, selectedPack);
+        const allocationStep = mode === 'pack' ? '1' : '1.0';
+        const batchAvailabilityNote = mode === 'pack'
+            ? (selectedPack && batchMatchesSelectedPack(batch, selectedPack) && availableFullPacks <= 0 ? 'No full packs available in this batch' : '')
+            : `Available to dispose: ${formatDisplayNumber(batch.quantity)} ${escapeHtml(unitLabel)}`;
+
+        return `
+            <div style="padding: 10px; margin: 6px 0; background: white; border: 1px solid #e0e0e0; border-radius: 4px; ${index === 0 ? 'border-left: 3px solid #2196F3; background: #f8fbff;' : ''}">
+                <div style="display: grid; grid-template-columns: minmax(0, 1.8fr) minmax(0, 1fr) 140px; gap: 12px; align-items: end;">
+                    <div>
+                        <div><strong>${escapeHtml(batch.batch_number)}</strong>${index === 0 ? ' <span style="background: #2196F3; color: white; padding: 2px 6px; border-radius: 2px; font-size: 0.8em; margin-left: 5px;">FEFO</span>' : ''}</div>
+                        <div style="font-size: 0.9em; color: #666; margin-top: 4px;">
+                            Available: <strong>${formatDisplayNumber(batch.quantity)} ${escapeHtml(unitLabel)}</strong> |
+                            Location: <strong>${escapeHtml(locationLabel)}</strong> |
+                            Expiry: <strong>${expiryLabel}</strong> <span style="color: ${statusColor};">(${expiryStatus})</span>
+                        </div>
+                    </div>
+                    <div style="font-size: 0.9em; color: #374151;">
+                        ${batch.current_full_pack_count != null && batch.current_loose_base_units != null && batch.received_pack_unit_name
+                            ? `Stock: ${formatDisplayNumber(batch.current_full_pack_count)} full ${escapeHtml(packLabel(batch.received_pack_unit_name, batch.received_pack_size_snapshot))} + ${formatDisplayNumber(batch.current_loose_base_units)} ${escapeHtml(unitLabel)} loose`
+                            : ''}
+                        ${batchAvailabilityNote ? `<div style="margin-top: 4px; color: #d32f2f;">${batchAvailabilityNote}</div>` : ''}
+                    </div>
+                    <div class="form-group" style="margin-bottom: 0;">
+                        <label for="disposeBatchAllocation-${batch.id}">${allocationLabel}</label>
+                        <input type="number" id="disposeBatchAllocation-${batch.id}" class="dispose-batch-allocation" data-batch-id="${batch.id}" min="0" max="${allocationMax}" step="${allocationStep}" value="0">
+                    </div>
+                </div>
+            </div>
+        `;
+    }).join('');
+
+    batchInfoContent.querySelectorAll('.dispose-batch-allocation').forEach(input => {
+        input.addEventListener('wheel', (event) => {
+            event.preventDefault();
+        }, { passive: false });
+        input.addEventListener('input', updateDisposeAllocationSummary);
+    });
+}
+
+function renderExpiredDisposeBatches(expiredBatches) {
+    const expiredDetails = document.getElementById('disposeExpiredBatchDetails');
+    const expiredContent = document.getElementById('disposeExpiredBatchContent');
+    const variantId = parseInt(document.getElementById('disposeDrugSelect').value || '', 10);
+    const variant = getVariantById(variantId);
+    const unitLabel = variant?.unit || 'units';
+    if (!expiredDetails || !expiredContent) return;
+
+    if (!expiredBatches.length) {
+        expiredDetails.style.display = 'none';
+        expiredDetails.open = false;
+        expiredContent.innerHTML = '';
+        return;
+    }
+
+    expiredDetails.style.display = 'block';
+    expiredContent.innerHTML = expiredBatches.map(batch => {
+        const locationLabel = getBatchLocationLabel(batch);
+        const stocktakeLabel = batch.current_full_pack_count != null && batch.current_loose_base_units != null && batch.received_pack_unit_name
+            ? `${formatDisplayNumber(batch.current_full_pack_count)} full ${escapeHtml(packLabel(batch.received_pack_unit_name, batch.received_pack_size_snapshot))} + ${formatDisplayNumber(batch.current_loose_base_units)} ${escapeHtml(unitLabel)} loose`
+            : `${formatDisplayNumber(batch.quantity)} ${escapeHtml(unitLabel)}`;
+
+        return `
+            <div style="padding: 8px; margin: 6px 0; background: white; border: 1px solid #f0d7a1; border-radius: 4px;">
+                <div style="display: flex; justify-content: space-between; gap: 8px; flex-wrap: wrap;">
+                    <strong>${escapeHtml(batch.batch_number)}</strong>
+                    <span style="color: #b45309; font-weight: 600;">Expired ${formatDisplayDate(batch.expiry_date)}</span>
+                </div>
+                <div style="font-size: 0.9em; color: #666; margin-top: 4px;">
+                    Qty: <strong>${formatDisplayNumber(batch.quantity)} ${escapeHtml(unitLabel)}</strong> |
+                    Location: <strong>${escapeHtml(locationLabel)}</strong>
+                </div>
+                <div style="font-size: 0.9em; color: #374151; margin-top: 4px;">${stocktakeLabel}</div>
+            </div>
+        `;
+    }).join('');
+}
+
+function renderDisposeInventorySourceView() {
+    const batchInfoContent = document.getElementById('disposeBatchInfoContent');
+    const variantId = parseInt(document.getElementById('disposeDrugSelect')?.value || '', 10);
+    const variant = getVariantById(variantId);
+    if (!batchInfoContent || !variant) return;
+
+    if (getSelectedDisposeMode() === 'pack') {
+        if (hasBatchDisposeStock()) {
+            renderDisposeBatchAllocationRows(currentDisposeBatches);
+            autoAllocateDisposeBatches();
+        } else if (hasLegacyDisposeQuantity()) {
+            batchInfoContent.innerHTML = `<div style="padding: 10px; background: #fff8e8; border: 1px solid #f3d18d; border-radius: 4px; color: #7a4f01;"><strong>Legacy stock only.</strong> ${formatDisplayNumber(currentDisposeLegacyQuantity)} ${escapeHtml(variant.unit || 'units')} available outside the batch system. Whole-pack disposal is unavailable.</div>`;
+            updateDisposeAllocationSummary();
+        } else {
+            batchInfoContent.innerHTML = '<p style="color: #d32f2f; margin: 0;">No active batches available for this variant</p>';
+            updateDisposeAllocationSummary();
+        }
+        return;
+    }
+
+    if (isLegacyDisposeSelected()) {
+        const extraText = hasBatchDisposeStock() ? ' Batch stock is also available; switch source to allocate from batches.' : ' Dispose by quantity only.';
+        batchInfoContent.innerHTML = `<div style="padding: 10px; background: #fff8e8; border: 1px solid #f3d18d; border-radius: 4px; color: #7a4f01;"><strong>Legacy loose stock selected.</strong> ${formatDisplayNumber(currentDisposeLegacyQuantity)} ${escapeHtml(variant.unit || 'units')} available outside the batch system.${extraText}</div>`;
+        updateDisposeAllocationSummary();
+        return;
+    }
+
+    if (hasBatchDisposeStock()) {
+        renderDisposeBatchAllocationRows(currentDisposeBatches);
+        autoAllocateDisposeBatches();
+        return;
+    }
+
+    if (hasLegacyDisposeQuantity()) {
+        batchInfoContent.innerHTML = `<div style="padding: 10px; background: #fff8e8; border: 1px solid #f3d18d; border-radius: 4px; color: #7a4f01;"><strong>Legacy stock only.</strong> ${formatDisplayNumber(currentDisposeLegacyQuantity)} ${escapeHtml(variant.unit || 'units')} available outside the batch system. Dispose by quantity only.</div>`;
+        updateDisposeAllocationSummary();
+        return;
+    }
+
+    batchInfoContent.innerHTML = '<p style="color: #d32f2f; margin: 0;">No active batches available for this variant</p>';
+    updateDisposeAllocationSummary();
+}
+
+async function updateDisposeBatchInfo() {
+    const variantId = parseInt(document.getElementById('disposeDrugSelect').value);
+    const batchInfoSection = document.getElementById('disposeBatchInfoSection');
+    const batchInfoContent = document.getElementById('disposeBatchInfoContent');
+
+    if (!variantId) {
+        batchInfoSection.style.display = 'none';
+        const packSelect = document.getElementById('disposePackSelect');
+        if (packSelect) packSelect.innerHTML = '<option value="">-- Select pack --</option>';
+        currentDisposeBatches = [];
+        currentDisposeLegacyQuantity = 0;
+        renderExpiredDisposeBatches([]);
+        updateDisposeSourceUi();
+        updateDisposeAllocationSummary();
+        return;
+    }
+
+    const variant = getVariantById(variantId);
+    if (variant) {
+        const drugOfVariant = allDrugs.find(d => (d.variants || []).some(v => v.id === variantId));
+        if (drugOfVariant) await ensureDrugDetailLoaded(drugOfVariant.id);
+        populateDisposePackSelect(getVariantById(variantId));
+    }
+    updateDisposeModeUi();
+
+    batchInfoSection.style.display = 'block';
+    batchInfoContent.innerHTML = '<p class="loading">Loading batches...</p>';
+    renderExpiredDisposeBatches([]);
+
+    try {
+        const response = await apiCall(`/variants/${variantId}/batches`);
+        if (!response.ok) throw new Error('Failed to load batches');
+        const batches = await response.json();
+        const stockedBatches = batches.filter(b => b.quantity > 0);
+        const expiredBatches = stockedBatches.filter(isBatchExpired);
+        const activeBatches = stockedBatches.filter(batch => !isBatchExpired(batch));
+        const totalBatchQuantity = stockedBatches.reduce((sum, batch) => sum + Number(batch.quantity || 0), 0);
+        currentDisposeLegacyQuantity = Math.max(0, Number(variant?.quantity || 0) - totalBatchQuantity);
+        activeBatches.sort((a, b) => new Date(a.expiry_date) - new Date(b.expiry_date));
+        currentDisposeBatches = activeBatches;
+        renderExpiredDisposeBatches(expiredBatches);
+        updateDisposeSourceUi();
+        renderDisposeInventorySourceView();
+    } catch (error) {
+        console.error('Error loading disposal batches:', error);
+        batchInfoContent.innerHTML = '<p style="color: #d32f2f; margin: 0;">Error loading batches</p>';
+        currentDisposeBatches = [];
+        currentDisposeLegacyQuantity = 0;
+        renderExpiredDisposeBatches([]);
+        updateDisposeSourceUi();
+        updateDisposeAllocationSummary();
+    }
+}
+
+function autoAllocateDisposeBatches() {
+    const requestedQuantity = getDisposeRequestedQuantity();
+    const allocationInputs = Array.from(document.querySelectorAll('.dispose-batch-allocation'));
+    const mode = getSelectedDisposeMode();
+    const selectedPack = getSelectedDisposePack();
+    if (!allocationInputs.length) {
+        updateDisposeAllocationSummary();
+        return;
+    }
+
+    if (isLegacyDisposeSelected()) {
+        allocationInputs.forEach(input => { input.value = '0'; });
+        updateDisposeAllocationSummary();
+        return;
+    }
+
+    let remaining = mode === 'pack'
+        ? Math.max(0, Math.round(parseFloat(document.getElementById('disposePackCount')?.value || '0')) || 0)
+        : requestedQuantity;
+    allocationInputs.forEach(input => {
+        const batchId = parseInt(input.dataset.batchId || '', 10);
+        const batch = currentDisposeBatches.find(row => row.id === batchId);
+        if (!batch || requestedQuantity <= 0) {
+            input.value = '0';
+            return;
+        }
+
+        let allocation = 0;
+        if (mode === 'pack' && selectedPack) {
+            const availableFullPacks = batchMatchesSelectedPack(batch, selectedPack)
+                ? Math.max(0, Math.floor(Number(batch.current_full_pack_count || 0)))
+                : 0;
+            allocation = Math.min(availableFullPacks, Math.max(remaining, 0));
+            input.value = allocation > 0 ? String(allocation) : '0';
+        } else {
+            allocation = Math.min(getBatchAvailableDisposeQuantity(batch, mode, selectedPack), Math.max(remaining, 0));
+            input.value = allocation > 0 ? String(Number(allocation.toFixed(3))) : '0';
+        }
+        remaining -= allocation;
+    });
+
+    updateDisposeAllocationSummary();
+}
+
+function updateDisposeAllocationSummary() {
+    const summarySection = document.getElementById('disposeAllocationSummary');
+    const summaryContent = document.getElementById('disposeAllocationSummaryContent');
+    const requestedQuantity = getDisposeRequestedQuantity();
+    const variantId = parseInt(document.getElementById('disposeDrugSelect').value || '', 10);
+    const unitLabel = getVariantById(variantId)?.unit || 'units';
+    const inputs = Array.from(document.querySelectorAll('.dispose-batch-allocation'));
+    const mode = getSelectedDisposeMode();
+    const selectedPack = getSelectedDisposePack();
+    const legacyStockOnly = isLegacyDisposeSelected();
+    const totalAvailableQuantity = getTotalAvailableDisposeQuantity(mode, selectedPack);
+    const totalAvailablePacks = mode === 'pack' ? getTotalAvailableDisposePackCount(selectedPack) : 0;
+
+    if (!summarySection || !summaryContent || !variantId || (!inputs.length && !legacyStockOnly)) {
+        if (summarySection) summarySection.style.display = 'none';
+        return;
+    }
+
+    const allocated = inputs.reduce((sum, input) => {
+        const value = parseFloat(input.value || '0');
+        return sum + (Number.isNaN(value) ? 0 : value);
+    }, 0);
+    const allocatedQuantity = mode === 'pack' && selectedPack ? allocated * selectedPack.pack_size_in_base_units : allocated;
+    const invalidInput = inputs.find(input => {
+        const batchId = parseInt(input.dataset.batchId || '', 10);
+        const batch = currentDisposeBatches.find(row => row.id === batchId);
+        const value = parseFloat(input.value || '0');
+        if (!batch || Number.isNaN(value)) return false;
+        if (mode === 'pack' && selectedPack) {
+            const availableFullPacks = batchMatchesSelectedPack(batch, selectedPack)
+                ? Math.max(0, Math.floor(Number(batch.current_full_pack_count || 0)))
+                : 0;
+            return value - availableFullPacks > 1e-6 || Math.abs(value - Math.round(value)) > 1e-6;
+        }
+        return value - getBatchAvailableDisposeQuantity(batch, mode, selectedPack) > 1e-6;
+    });
+
+    const difference = requestedQuantity - allocatedQuantity;
+    summarySection.style.display = 'block';
+
+    if (requestedQuantity <= 0) {
+        summaryContent.innerHTML = legacyStockOnly
+            ? `<span style="color: #666;">Enter a disposal quantity. ${formatDisplayNumber(currentDisposeLegacyQuantity)} ${escapeHtml(unitLabel)} of legacy stock is available outside batches.</span>`
+            : '<span style="color: #666;">Enter a disposal amount to allocate batches.</span>';
+        return;
+    }
+
+    if (legacyStockOnly) {
+        if (requestedQuantity - currentDisposeLegacyQuantity > 1e-6) {
+            summaryContent.innerHTML = `<span style="color: #d32f2f; font-weight: 600;">Requested ${formatDisplayNumber(requestedQuantity)} ${escapeHtml(unitLabel)} but only ${formatDisplayNumber(currentDisposeLegacyQuantity)} ${escapeHtml(unitLabel)} of legacy stock is available.</span>`;
+            return;
+        }
+        summaryContent.innerHTML = `<span style="color: #1565c0; font-weight: 600;">Disposing ${formatDisplayNumber(requestedQuantity)} ${escapeHtml(unitLabel)} from legacy stock outside batches.</span>`;
+        return;
+    }
+
+    if (mode === 'pack' && selectedPack) {
+        const requestedPackCount = parseFloat(document.getElementById('disposePackCount')?.value || '0');
+        if (totalAvailablePacks <= 0) {
+            summaryContent.innerHTML = `<span style="color: #d32f2f; font-weight: 600;">No full ${escapeHtml(selectedPack.pack_unit_name)} packs are available to dispose.</span>`;
+            return;
+        }
+        if (!Number.isNaN(requestedPackCount) && requestedPackCount > totalAvailablePacks) {
+            summaryContent.innerHTML = `<span style="color: #d32f2f; font-weight: 600;">Only ${totalAvailablePacks} full ${escapeHtml(selectedPack.pack_unit_name)} pack${totalAvailablePacks === 1 ? '' : 's'} are available.</span>`;
+            return;
+        }
+    }
+
+    if (requestedQuantity - totalAvailableQuantity > 1e-6) {
+        summaryContent.innerHTML = `<span style="color: #d32f2f; font-weight: 600;">Requested ${formatDisplayNumber(requestedQuantity)} ${escapeHtml(unitLabel)} but only ${formatDisplayNumber(totalAvailableQuantity)} ${escapeHtml(unitLabel)} available.</span>`;
+        return;
+    }
+    if (invalidInput) {
+        summaryContent.innerHTML = '<span style="color: #d32f2f; font-weight: 600;">One or more batch allocations exceed available stock or are not valid full-pack amounts.</span>';
+        return;
+    }
+    if (Math.abs(difference) <= 1e-6) {
+        if (mode === 'pack' && selectedPack) {
+            const requestedPackCount = parseFloat(document.getElementById('disposePackCount')?.value || '0');
+            summaryContent.innerHTML = `<span style="color: #1565c0; font-weight: 600;">Allocated ${formatDisplayNumber(allocated)} pack${allocated === 1 ? '' : 's'} of ${formatDisplayNumber(requestedPackCount)} requested (${formatDisplayNumber(allocatedQuantity)} ${escapeHtml(unitLabel)}).</span>`;
+        } else {
+            summaryContent.innerHTML = `<span style="color: #1565c0; font-weight: 600;">Allocated ${formatDisplayNumber(allocatedQuantity)} ${escapeHtml(unitLabel)} of ${formatDisplayNumber(requestedQuantity)} requested.</span>`;
+        }
+        return;
+    }
+    if (difference > 0) {
+        summaryContent.innerHTML = `<span style="color: #d32f2f; font-weight: 600;">Allocate ${formatDisplayNumber(difference)} more ${escapeHtml(unitLabel)} to match the requested total.</span>`;
+        return;
+    }
+    summaryContent.innerHTML = `<span style="color: #d32f2f; font-weight: 600;">Reduce allocations by ${formatDisplayNumber(Math.abs(difference))} ${escapeHtml(unitLabel)} to match the requested total.</span>`;
+}
+
 // Render drugs list
 function renderDrugs() {
     const drugsList = document.getElementById('drugsList');
@@ -1729,6 +2335,7 @@ function renderDrugs() {
         const isLowStock = lowStockVariants > 0;
         const isExpanded = expandedDrugs.has(drug.id);
         const isReadOnly = currentUser.role === 'readonly';
+        const isAdmin = currentUser.role === 'admin';
         const isControlled = drug.is_controlled;
         const drugDetail = loadedDrugDetails.get(drug.id);
 
@@ -1771,6 +2378,7 @@ function renderDrugs() {
                             <div class="variant-actions">
                                 ${!isReadOnly ? `
                                     <button class="btn btn-success btn-small" onclick="event.stopPropagation(); dispenseVariant(${summaryVariant.id})">💊 Dispense</button>
+                                    ${isAdmin ? `<button class="btn btn-danger btn-small" onclick="event.stopPropagation(); disposeVariant(${summaryVariant.id})">Dispose</button>` : ''}
                                     <button class="btn btn-warning btn-small" onclick="event.stopPropagation(); openEditVariantModal(${summaryVariant.id})">Edit</button>
                                     <button class="btn btn-danger btn-small" onclick="event.stopPropagation(); deleteVariant(${summaryVariant.id})" title="${summaryVariant.has_inventory_history ? 'Variant has history and cannot be deleted' : ''}">Delete</button>
                                 ` : ''}
@@ -2046,6 +2654,144 @@ async function handleDispenseDrug(e) {
     }
 }
 
+async function handleDisposeInventory(e) {
+    e.preventDefault();
+
+    const variantId = parseInt(document.getElementById('disposeDrugSelect').value);
+    let quantity = parseFloat(document.getElementById('disposeQuantity').value);
+    const disposeMode = getSelectedDisposeMode();
+    const disposeSource = getSelectedDisposeSource();
+    const requestedPackIdValue = document.getElementById('disposePackSelect').value;
+    const requestedPackCountValue = document.getElementById('disposePackCount').value;
+    const notes = document.getElementById('disposeNotes')?.value.trim() || '';
+
+    const selectedPackId = requestedPackIdValue ? parseInt(requestedPackIdValue, 10) : null;
+    const selectedPackCount = requestedPackCountValue ? parseFloat(requestedPackCountValue) : null;
+    const variant = getVariantById(variantId);
+    const legacyStockOnly = isLegacyDisposeSelected();
+    const selectedPack = variant && selectedPackId
+        ? getActivePacksForVariant(variant).find(pack => pack.id === selectedPackId)
+        : null;
+
+    if (!['subunit', 'pack'].includes(disposeMode)) {
+        showToast('Please select a valid disposal mode.', 'warning');
+        return;
+    }
+
+    if (disposeMode === 'pack') {
+        if (legacyStockOnly) {
+            showToast('Whole-pack disposal is unavailable for stock that is not attached to batches.', 'warning');
+            return;
+        }
+        if (!selectedPack) {
+            showToast('Please select a pack type for whole-pack disposal.', 'warning');
+            return;
+        }
+        if (selectedPackCount == null || Number.isNaN(selectedPackCount) || selectedPackCount <= 0) {
+            showToast('Please enter a valid pack count greater than zero.', 'warning');
+            return;
+        }
+        if (Math.abs(selectedPackCount - Math.round(selectedPackCount)) > 1e-6) {
+            showToast('Whole-pack disposal requires a whole-number pack count.', 'warning');
+            return;
+        }
+        quantity = selectedPackCount * selectedPack.pack_size_in_base_units;
+    }
+
+    const allocationEntries = Array.from(document.querySelectorAll('.dispose-batch-allocation'))
+        .map(input => ({
+            batch_id: parseInt(input.dataset.batchId || '', 10),
+            entered_value: parseFloat(input.value || '0')
+        }))
+        .filter(entry => !Number.isNaN(entry.batch_id) && !Number.isNaN(entry.entered_value) && entry.entered_value > 0);
+
+    const allocations = allocationEntries.map(entry => ({
+        batch_id: entry.batch_id,
+        quantity: disposeMode === 'pack' && selectedPack
+            ? entry.entered_value * selectedPack.pack_size_in_base_units
+            : entry.entered_value
+    }));
+
+    const allocatedTotal = allocations.reduce((sum, entry) => sum + entry.quantity, 0);
+    const totalAvailableQuantity = getTotalAvailableDisposeQuantity(disposeMode, selectedPack);
+    const totalAvailablePacks = disposeMode === 'pack' ? getTotalAvailableDisposePackCount(selectedPack) : 0;
+
+    if (!variantId || Number.isNaN(quantity) || quantity <= 0) {
+        showToast('Please fill in all required fields (Drug Variant and Quantity > 0)', 'warning');
+        return;
+    }
+
+    if (quantity - totalAvailableQuantity > 1e-6) {
+        if (disposeMode === 'pack' && selectedPack) {
+            showToast(`Only ${totalAvailablePacks} full ${selectedPack.pack_unit_name} pack${totalAvailablePacks === 1 ? '' : 's'} available.`, 'warning');
+        } else {
+            showToast(`Requested quantity exceeds available stock (${formatDisplayNumber(totalAvailableQuantity)} available).`, 'warning');
+        }
+        return;
+    }
+
+    if (!legacyStockOnly && allocations.length === 0) {
+        showToast('Allocate quantity against at least one batch.', 'warning');
+        return;
+    }
+
+    if (disposeMode === 'pack' && selectedPack) {
+        const invalidPackAllocation = allocationEntries.find(entry => {
+            const batch = currentDisposeBatches.find(row => row.id === entry.batch_id);
+            const availableFullPacks = batchMatchesSelectedPack(batch, selectedPack)
+                ? Math.max(0, Math.floor(Number(batch.current_full_pack_count || 0)))
+                : 0;
+            return !batch
+                || entry.entered_value - availableFullPacks > 1e-6
+                || Math.abs(entry.entered_value - Math.round(entry.entered_value)) > 1e-6;
+        });
+
+        if (invalidPackAllocation) {
+            showToast('Whole-pack allocations must use batches with available full packs and whole-pack multiples only.', 'warning');
+            return;
+        }
+    }
+
+    if (!legacyStockOnly && Math.abs(allocatedTotal - quantity) > 1e-6) {
+        showToast('Batch allocations must exactly match the requested disposal quantity.', 'warning');
+        return;
+    }
+
+    if (!confirm(`Dispose ${formatDisplayNumber(quantity)} ${variant?.unit || 'units'} from inventory?`)) {
+        return;
+    }
+
+    try {
+        const response = await apiCall('/dispose', {
+            method: 'POST',
+            body: JSON.stringify({
+                drug_variant_id: variantId,
+                quantity,
+                dispense_mode: disposeMode,
+                requested_pack_id: disposeMode === 'pack' ? selectedPackId : null,
+                requested_pack_count: disposeMode === 'pack' ? selectedPackCount : null,
+                dispense_source: disposeSource,
+                notes: notes || null,
+                allocations
+            })
+        });
+
+        if (!response.ok) {
+            const error = await response.json();
+            throw new Error(error.detail || 'Failed to dispose inventory');
+        }
+
+        document.getElementById('disposeInventoryForm').reset();
+        closeModal(document.getElementById('disposeInventoryModal'));
+        loadedVariantBatches.delete(variantId);
+        await loadDrugs();
+        showToast('Inventory disposed successfully.', 'success');
+    } catch (error) {
+        console.error('Error disposing inventory:', error);
+        showToast('Failed to dispose inventory: ' + error.message, 'error');
+    }
+}
+
 // Open edit modal
 function openEditModal(drugId) {
     const drug = allDrugs.find(d => d.id === drugId);
@@ -2518,6 +3264,22 @@ function dispenseVariant(variantId) {
     openModal(document.getElementById('dispenseModal'));
 }
 
+function disposeVariant(variantId) {
+    if (currentUser?.role !== 'admin') {
+        showToast('Only admin users can dispose inventory.', 'warning');
+        return;
+    }
+
+    document.getElementById('disposeInventoryForm')?.reset();
+    updateDisposeDrugSelect();
+
+    const drugSelect = document.getElementById('disposeDrugSelect');
+    drugSelect.value = variantId;
+
+    updateDisposeBatchInfo();
+    openModal(document.getElementById('disposeInventoryModal'));
+}
+
 // Handle print notes form submission
 async function handlePrintNotes(e) {
     e.preventDefault();
@@ -2879,21 +3641,38 @@ async function openUserManagement() {
 
         const users = await response.json();
         
+        const roleOptions = [
+            { value: 'admin', label: 'Admin' },
+            { value: 'user', label: 'Regular User' },
+            { value: 'readonly', label: 'Read-Only' }
+        ];
+
         const usersHtml = `
             <h3>Users</h3>
             <div class="users-table">
                 ${users.map(user => {
-                    const roleLabel = user.role.charAt(0).toUpperCase() + user.role.slice(1);
                     const roleBadge = user.role === 'admin' ? '👑 Admin' : 
                                      user.role === 'readonly' ? '👁️ Read-Only' : '👤 Regular';
+                    const isCurrentUser = user.id === currentUser.id;
                     return `
                         <div class="user-item">
-                            <span>${user.username}</span>
-                            <span class="admin-badge">${roleBadge}</span>
-                            <button class="btn btn-secondary btn-small" onclick="openAdminChangePasswordModal(${user.id}, '${escapeHtml(user.username)}')">🔑 Password</button>
-                            ${user.id !== currentUser.id ? `
-                                <button class="btn btn-danger btn-small" onclick="deleteUser(${user.id})">Delete</button>
-                            ` : ''}
+                            <div class="user-identity">
+                                <strong>${escapeHtml(user.username)}</strong>
+                                ${isCurrentUser ? '<span class="current-user-label">You</span>' : ''}
+                            </div>
+                            <span class="admin-badge role-${escapeHtml(user.role)}">${roleBadge}</span>
+                            <label class="role-control">
+                                <span>Role</span>
+                                <select class="user-role-select" data-user-id="${user.id}" ${isCurrentUser ? 'disabled' : ''}>
+                                    ${roleOptions.map(role => `<option value="${role.value}" ${role.value === user.role ? 'selected' : ''}>${role.label}</option>`).join('')}
+                                </select>
+                            </label>
+                            <div class="user-actions">
+                                ${!isCurrentUser ? `
+                                    <button class="btn btn-secondary btn-small admin-password-btn" data-user-id="${user.id}" data-username="${escapeHtml(user.username)}">Password</button>
+                                    <button class="btn btn-danger btn-small delete-user-btn" data-user-id="${user.id}">Delete</button>
+                                ` : '<span class="self-note">Use account menu for your password</span>'}
+                            </div>
                         </div>
                     `;
                 }).join('')}
@@ -2901,6 +3680,15 @@ async function openUserManagement() {
         `;
         
         usersList.innerHTML = usersHtml;
+        usersList.querySelectorAll('.user-role-select').forEach(select => {
+            select.addEventListener('change', (e) => updateUserRole(e.target.dataset.userId, e.target.value));
+        });
+        usersList.querySelectorAll('.admin-password-btn').forEach(button => {
+            button.addEventListener('click', () => openAdminChangePasswordModal(button.dataset.userId, button.dataset.username));
+        });
+        usersList.querySelectorAll('.delete-user-btn').forEach(button => {
+            button.addEventListener('click', () => deleteUser(button.dataset.userId));
+        });
     } catch (error) {
         console.error('Error loading users:', error);
         usersList.innerHTML = '<h3>Users</h3><p class="empty">Error loading users</p>';
@@ -2949,6 +3737,28 @@ async function createUser(e) {
     }
 }
 
+// Update user role
+async function updateUserRole(userId, role) {
+    try {
+        const response = await apiCall(`/users/${userId}/role`, {
+            method: 'PATCH',
+            body: JSON.stringify({ role })
+        });
+
+        if (!response.ok) {
+            const error = await response.json();
+            throw new Error(error.detail || 'Failed to update user role');
+        }
+
+        showToast('User role updated successfully!', 'success');
+        openUserManagement();
+    } catch (error) {
+        console.error('Error updating user role:', error);
+        showToast('Failed to update user role: ' + error.message, 'error');
+        openUserManagement();
+    }
+}
+
 // Delete user
 async function deleteUser(userId) {
     if (!confirm('Are you sure you want to delete this user?')) return;

frontend/index.html

@@ -264,6 +264,95 @@
             </div>
         </div>
 
+        <!-- Dispose Inventory Modal -->
+        <div id="disposeInventoryModal" class="modal">
+            <div class="modal-content modal-large dispense-modal-content">
+                <span class="close">&times;</span>
+                <h2>Dispose Inventory</h2>
+                <form id="disposeInventoryForm" novalidate>
+                    <div class="form-group">
+                        <label for="disposeDrugSelect">Drug Variant *</label>
+                        <select id="disposeDrugSelect" onchange="updateDisposeBatchInfo()">
+                            <option value="">-- Select a drug variant --</option>
+                        </select>
+                    </div>
+
+                    <div class="form-group">
+                        <label>Disposal Mode *</label>
+                        <div style="display: flex; gap: 18px; align-items: center; flex-wrap: wrap; margin-top: 6px;">
+                            <label style="display: inline-flex; align-items: center; gap: 8px; margin: 0; font-weight: 500;">
+                                <input type="radio" name="disposeMode" id="disposeModeQuantity" value="subunit" checked>
+                                Quantity
+                            </label>
+                            <label style="display: inline-flex; align-items: center; gap: 8px; margin: 0; font-weight: 500;">
+                                <input type="radio" name="disposeMode" id="disposeModePack" value="pack">
+                                Whole Pack
+                            </label>
+                        </div>
+                    </div>
+
+                    <div class="form-group" id="disposeQuantityGroup">
+                        <label for="disposeQuantity">Quantity *</label>
+                        <input type="number" id="disposeQuantity" step="1.0">
+                    </div>
+
+                    <div class="form-row" id="disposePackRow" style="display: none;">
+                        <div class="form-group">
+                            <label for="disposePackSelect">Pack Type *</label>
+                            <select id="disposePackSelect" onchange="updateDisposeQuantityFromPack()">
+                                <option value="">-- Select pack --</option>
+                            </select>
+                        </div>
+                        <div class="form-group">
+                            <label for="disposePackCount">Pack Count *</label>
+                            <input type="number" id="disposePackCount" min="1" step="1" onchange="updateDisposeQuantityFromPack()">
+                            <small id="disposePackPreview" style="display: block; margin-top: 6px; color: #666;">Select a pack and whole-number count.</small>
+                        </div>
+                    </div>
+
+                    <div class="form-group" id="disposeSourceGroup" style="display: none;">
+                        <label>Stock Source *</label>
+                        <div style="display: flex; gap: 18px; align-items: center; flex-wrap: wrap; margin-top: 6px;">
+                            <label style="display: inline-flex; align-items: center; gap: 8px; margin: 0; font-weight: 500;">
+                                <input type="radio" name="disposeSource" id="disposeSourceBatch" value="batch" checked>
+                                Batch stock
+                            </label>
+                            <label style="display: inline-flex; align-items: center; gap: 8px; margin: 0; font-weight: 500;">
+                                <input type="radio" name="disposeSource" id="disposeSourceLegacy" value="legacy">
+                                Legacy loose stock
+                            </label>
+                        </div>
+                        <small id="disposeSourceHelp" style="display: block; margin-top: 6px; color: #666;"></small>
+                    </div>
+
+                    <div id="disposeBatchInfoSection" style="display: none; margin: 15px 0; padding: 12px; background: #f5f5f5; border-radius: 4px;">
+                        <h4 style="margin-top: 0; margin-bottom: 4px;">Batch Allocation</h4>
+                        <p style="margin: 0 0 10px; color: #666;">Batches are shown in FEFO order. Adjust the allocation against each batch so the total matches the requested disposal amount.</p>
+                        <details id="disposeExpiredBatchDetails" style="display: none; margin-bottom: 10px; background: #fffaf0; border: 1px solid #f5d08a; border-radius: 4px; padding: 8px 10px;">
+                            <summary style="cursor: pointer; font-weight: 600; color: #7a4f01;">Show expired batches</summary>
+                            <div id="disposeExpiredBatchContent" style="margin-top: 10px;"></div>
+                        </details>
+                        <div id="disposeAllocationSummary" style="display: none; margin-bottom: 10px; padding: 8px 10px; background: #f0f8ff; border-left: 3px solid #2196F3; border-radius: 4px;">
+                            <div id="disposeAllocationSummaryContent"></div>
+                        </div>
+                        <div id="disposeBatchInfoContent">
+                            <p class="loading">Loading batches...</p>
+                        </div>
+                    </div>
+
+                    <div class="form-group">
+                        <label for="disposeNotes">Disposal Note</label>
+                        <textarea id="disposeNotes" rows="4" placeholder="Optional note for the audit log"></textarea>
+                    </div>
+
+                    <div class="form-actions">
+                        <button type="submit" class="btn btn-danger">Dispose</button>
+                        <button type="button" class="btn btn-secondary" id="cancelDisposeInventoryBtn">Cancel</button>
+                    </div>
+                </form>
+            </div>
+        </div>
+
         <!-- Add Variant Modal -->
         <div id="addVariantModal" class="modal">
             <div class="modal-content">
@@ -432,7 +521,7 @@
                 <span class="close">&times;</span>
                 <h2>User Management</h2>
                 <div class="user-management-content">
-                    <div class="form-group">
+                    <section class="user-create-panel">
                         <h3>Create New User</h3>
                         <form id="createUserForm">
                             <div class="form-row">
@@ -447,7 +536,7 @@
                             </div>
                             <button type="submit" class="btn btn-primary btn-small">Create User</button>
                         </form>
-                    </div>
+                    </section>
                     <div id="usersList" class="users-list">
                         <h3>Users</h3>
                         <p class="loading">Loading users...</p>
@@ -522,6 +611,11 @@
                         <input type="text" id="disposeBatchName" disabled>
                     </div>
 
+                    <div class="form-group">
+                        <label for="disposeBatchStockSummary">Stock to Dispose</label>
+                        <input type="text" id="disposeBatchStockSummary" disabled>
+                    </div>
+
                     <div class="form-group">
                         <p style="margin: 0; color: #666;">This will mark the expired batch as disposed and remove its remaining stock from inventory.</p>
                     </div>

frontend/styles.css

@@ -685,7 +685,8 @@ footer {
     max-height: calc(100vh - 48px) !important;
 }
 
-#dispenseModal.show {
+#dispenseModal.show,
+#disposeInventoryModal.show {
     align-items: flex-start;
     overflow-y: auto;
     padding: 24px 0;
@@ -697,19 +698,22 @@ footer {
     overflow-y: auto;
 }
 
-#dispenseForm {
+#dispenseForm,
+#disposeInventoryForm {
     display: block;
     padding-right: 6px;
 }
 
 #batchInfoSection,
+#disposeBatchInfoSection,
 #allocationPreviewSection {
     max-height: 220px;
     overflow-y: auto;
     min-height: fit-content;
 }
 
-#dispenseModal .form-actions {
+#dispenseModal .form-actions,
+#disposeInventoryModal .form-actions {
     margin-top: 16px;
     padding-top: 14px;
     background: var(--white);
@@ -1069,11 +1073,13 @@ footer {
         max-height: calc(100vh - 24px);
     }
 
-    #dispenseModal.show {
+    #dispenseModal.show,
+    #disposeInventoryModal.show {
         padding: 12px 0;
     }
 
     #batchInfoSection,
+    #disposeBatchInfoSection,
     #allocationPreviewSection {
         max-height: 160px;
     }
@@ -1195,22 +1201,29 @@ footer {
 }
 
 .user-management-content h3 {
-    margin-top: 20px;
+    margin-top: 0;
     margin-bottom: 15px;
     color: var(--primary-color);
 }
 
+.user-create-panel {
+    padding: 16px;
+    border: 1px solid var(--border-color);
+    border-radius: 8px;
+    background: #f8fafc;
+}
+
 .user-management-content .form-row {
-    display: flex;
+    display: grid;
+    grid-template-columns: minmax(150px, 1fr) minmax(150px, 1fr) minmax(150px, 0.8fr);
     gap: 10px;
     margin-bottom: 15px;
-    flex-wrap: wrap;
 }
 
 .user-management-content input,
 .user-management-content select {
-    flex: 1;
-    min-width: 150px;
+    width: 100%;
+    min-width: 0;
     padding: 10px;
     border: 1px solid var(--border-color);
     border-radius: 6px;
@@ -1222,33 +1235,103 @@ footer {
 }
 
 .users-list {
-    margin-top: 20px;
+    margin-top: 24px;
 }
 
 .users-table {
     display: flex;
     flex-direction: column;
-    gap: 10px;
+    gap: 8px;
 }
 
 .user-item {
-    display: flex;
-    justify-content: space-between;
+    display: grid;
+    grid-template-columns: minmax(140px, 1fr) minmax(110px, auto) minmax(170px, 0.8fr) minmax(190px, auto);
     align-items: center;
-    padding: 12px;
-    background: #f8f9fa;
+    padding: 12px 14px;
+    background: var(--white);
     border: 1px solid var(--border-color);
-    border-radius: 6px;
-    gap: 15px;
+    border-radius: 8px;
+    gap: 12px;
+}
+
+.user-identity {
+    display: flex;
+    align-items: center;
+    gap: 8px;
+    min-width: 0;
+}
+
+.user-identity strong {
+    overflow-wrap: anywhere;
+}
+
+.current-user-label,
+.self-note {
+    color: #64748b;
+    font-size: 0.85em;
+}
+
+.current-user-label {
+    padding: 2px 8px;
+    border-radius: 999px;
+    background: #e2e8f0;
+    color: #334155;
 }
 
 .admin-badge {
-    padding: 4px 12px;
-    background: var(--warning-color);
+    justify-self: start;
+    padding: 5px 10px;
     color: var(--white);
-    border-radius: 20px;
-    font-size: 0.9em;
+    border-radius: 999px;
+    font-size: 0.85em;
     font-weight: 500;
+    white-space: nowrap;
+}
+
+.admin-badge.role-admin {
+    background: var(--warning-color);
+}
+
+.admin-badge.role-user {
+    background: var(--secondary-color);
+}
+
+.admin-badge.role-readonly {
+    background: #64748b;
+}
+
+.role-control {
+    display: flex;
+    align-items: center;
+    gap: 8px;
+}
+
+.role-control span {
+    color: #64748b;
+    font-size: 0.85em;
+}
+
+.role-control select {
+    margin: 0;
+}
+
+.role-control select:disabled {
+    color: #64748b;
+    background: #f1f5f9;
+    cursor: not-allowed;
+}
+
+.user-actions {
+    display: flex;
+    justify-content: flex-end;
+    align-items: center;
+    gap: 8px;
+    flex-wrap: wrap;
+}
+
+.user-actions .btn {
+    margin-bottom: 0;
 }
 
 /* Responsive Styles */
@@ -1278,6 +1361,15 @@ footer {
         max-width: none;
     }
 
+    .user-management-content .form-row,
+    .user-item {
+        grid-template-columns: 1fr;
+    }
+
+    .user-actions {
+        justify-content: flex-start;
+    }
+
     .drug-item {
         flex-direction: column;
     }