Introduce spice_stock_movements ledger for traceable stock changes

Every delivery and batch now writes a signed movement entry instead of
directly incrementing/decrementing spice.quantity. The balance is always
the sum of all movements. Existing data is backfilled in the migration.
Rohstoff edit page shows the full movement history (Lagerbewegungen tab).

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

app/Filament/User/Resources/SpiceResource.php

@@ -78,7 +78,7 @@ class SpiceResource extends Resource
     public static function getRelations(): array
     {
         return [
-            //
+            RelationManagers\StockMovementsRelationManager::class,
         ];
     }
 

app/Filament/User/Resources/SpiceResource/RelationManagers/StockMovementsRelationManager.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace App\Filament\User\Resources\SpiceResource\RelationManagers;
+
+use Filament\Resources\RelationManagers\RelationManager;
+use Filament\Tables;
+use Filament\Tables\Table;
+
+class StockMovementsRelationManager extends RelationManager
+{
+    protected static string $relationship = 'stockMovements';
+    protected static ?string $title = 'Lagerbewegungen';
+
+    public function table(Table $table): Table
+    {
+        return $table
+            ->columns([
+                Tables\Columns\TextColumn::make('created_at')
+                    ->label('Datum')
+                    ->dateTime('d.m.Y H:i')
+                    ->sortable(),
+
+                Tables\Columns\TextColumn::make('description')
+                    ->label('Beschreibung'),
+
+                Tables\Columns\TextColumn::make('amount')
+                    ->label('Menge')
+                    ->formatStateUsing(fn ($state) => ($state > 0 ? '+' : '') . number_format($state, 2, ',', '.') . 'g')
+                    ->color(fn ($state) => $state > 0 ? 'success' : 'danger'),
+            ])
+            ->defaultSort('created_at', 'desc')
+            ->paginated([25, 50]);
+    }
+}

app/Filament/User/Resources/SpiceSupplierResource/Pages/CreateSpiceSupplier.php

@@ -4,17 +4,8 @@ namespace App\Filament\User\Resources\SpiceSupplierResource\Pages;
 
 use App\Filament\User\Resources\SpiceSupplierResource;
 use Filament\Resources\Pages\CreateRecord;
-use Illuminate\Database\Eloquent\Model;
-use App\Models\Spice;
 
 class CreateSpiceSupplier extends CreateRecord
 {
     protected static string $resource = SpiceSupplierResource::class;
-
-    protected function handleRecordCreation(array $data): Model {
-        $record = static::getModel()::create($data);
-
-        Spice::findOrFail($data['spice_id'])->increment('quantity', $data['amount']);
-        return $record;
-    }
 }

app/Filament/User/Resources/SpiceSupplierResource/Pages/EditSpiceSupplier.php

@@ -16,14 +16,9 @@ class EditSpiceSupplier extends EditRecord
                 ->requiresConfirmation()
                 ->modalHeading('Lieferung löschen')
                 ->modalDescription(fn ($record) => $record->spice && $record->spice->quantity < $record->amount
-                    ? 'Warnung: Nicht mehr genügend ' . $record->spice->name . ' im Lager. Der Bestand wird auf 0 gesetzt. Trotzdem löschen?'
+                    ? 'Warnung: Nach dem Löschen wird der Bestand von ' . $record->spice->name . ' negativ.'
                     : 'Soll diese Lieferung wirklich gelöscht werden?'
-                )
-                ->before(function ($record) {
-                    if ($record->spice) {
-                        $record->spice->decrement('quantity', $record->amount);
-                    }
-                }),
+                ),
         ];
     }
 }

app/Models/Batch.php

@@ -38,58 +38,62 @@ class Batch extends Model
 
     protected static function booted(): void
     {
-        // Auto-calculate quantity_g before saving
         static::saving(function (Batch $batch) {
             if ($batch->units_produced && $batch->size_id) {
-                $gramsPerUnit = $batch->size?->packing?->size ?? 0;
-                $batch->quantity_g = $batch->units_produced * $gramsPerUnit;
+                $batch->quantity_g = $batch->units_produced * ($batch->size?->packing?->size ?? 0);
             }
         });
 
         static::created(function (Batch $batch) {
-            $batch->deductSpices();
+            $batch->writeSpiceMovements();
         });
 
         static::updated(function (Batch $batch) {
             if ($batch->wasChanged(['recipe_id', 'size_id', 'units_produced'])) {
-                $batch->restoreSpices(
-                    $batch->getOriginal('recipe_id'),
-                    $batch->getOriginal('quantity_g'),
-                );
-                $batch->deductSpices();
+                $batch->deleteSpiceMovements();
+                $batch->writeSpiceMovements();
             }
         });
 
         static::deleting(function (Batch $batch) {
-            $batch->restoreSpices($batch->recipe_id, $batch->quantity_g);
+            $batch->deleteSpiceMovements();
         });
     }
 
-    private function deductSpices(): void
+    private function writeSpiceMovements(): void
     {
         if (! $this->quantity_g || ! $this->recipe_id) {
             return;
         }
 
         $recipe = Recipe::with('spices')->find($this->recipe_id);
-
-        foreach ($recipe->spices as $spice) {
-            $grams = $this->quantity_g * $spice->pivot->amount_in_percent / 100;
-            $spice->decrement('quantity', $grams);
-        }
-    }
-
-    private function restoreSpices(int $recipeId, float $quantityG): void
-    {
-        if (! $quantityG || ! $recipeId) {
+        if (! $recipe) {
             return;
         }
 
-        $recipe = Recipe::with('spices')->find($recipeId);
-
         foreach ($recipe->spices as $spice) {
-            $grams = $quantityG * $spice->pivot->amount_in_percent / 100;
-            $spice->increment('quantity', $grams);
+            $grams = $this->quantity_g * $spice->pivot->amount_in_percent / 100;
+            SpiceStockMovement::create([
+                'spice_id'    => $spice->id,
+                'amount'      => -$grams,
+                'source_type' => 'batch',
+                'source_id'   => $this->id,
+                'description' => 'Charge ' . $this->lot_number . ' (' . $spice->pivot->amount_in_percent . '%)',
+            ]);
+            $spice->recalculateQuantity();
         }
     }
+
+    private function deleteSpiceMovements(): void
+    {
+        $spiceIds = SpiceStockMovement::where('source_type', 'batch')
+            ->where('source_id', $this->id)
+            ->pluck('spice_id');
+
+        SpiceStockMovement::where('source_type', 'batch')
+            ->where('source_id', $this->id)
+            ->delete();
+
+        Spice::whereIn('id', $spiceIds)->get()->each->recalculateQuantity();
+    }
 }

app/Models/Spice.php

@@ -14,4 +14,14 @@ class Spice extends Model
                     ->withPivot('amount_in_percent')
                     ->withTimestamps();
     }
+
+    public function stockMovements()
+    {
+        return $this->hasMany(SpiceStockMovement::class);
+    }
+
+    public function recalculateQuantity(): void
+    {
+        $this->update(['quantity' => $this->stockMovements()->sum('amount')]);
+    }
 }

app/Models/SpiceStockMovement.php

@@ -0,0 +1,15 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class SpiceStockMovement extends Model
+{
+    protected $fillable = ['spice_id', 'amount', 'source_type', 'source_id', 'description'];
+
+    public function spice()
+    {
+        return $this->belongsTo(Spice::class);
+    }
+}

app/Models/SpiceSupplier.php

@@ -18,7 +18,6 @@ class SpiceSupplier extends Model
         'supplied_at',
     ];
 
-    // Beziehungen
     public function spice()
     {
         return $this->belongsTo(Spice::class);
@@ -28,4 +27,25 @@ class SpiceSupplier extends Model
     {
         return $this->belongsTo(Supplier::class);
     }
+
+    protected static function booted(): void
+    {
+        static::created(function (SpiceSupplier $ss) {
+            SpiceStockMovement::create([
+                'spice_id'    => $ss->spice_id,
+                'amount'      => $ss->amount,
+                'source_type' => 'delivery',
+                'source_id'   => $ss->id,
+                'description' => 'Lieferung' . ($ss->supplier ? ' von ' . $ss->supplier->name : ''),
+            ]);
+            $ss->spice->recalculateQuantity();
+        });
+
+        static::deleted(function (SpiceSupplier $ss) {
+            SpiceStockMovement::where('source_type', 'delivery')
+                ->where('source_id', $ss->id)
+                ->delete();
+            $ss->spice->recalculateQuantity();
+        });
+    }
 }

database/migrations/2026_09_12_250000_create_spice_stock_movements.php

@@ -0,0 +1,67 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('spice_stock_movements', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('spice_id')->constrained('spices')->cascadeOnDelete();
+            $table->decimal('amount', 10, 2); // positiv = Zugang, negativ = Abgang
+            $table->enum('source_type', ['delivery', 'batch']);
+            $table->unsignedBigInteger('source_id');
+            $table->string('description');
+            $table->timestamps();
+
+            $table->index(['spice_id', 'created_at']);
+        });
+
+        // Bestehende Lieferungen als Bewegungen einlesen
+        DB::table('spices_suppliers')->orderBy('id')->each(function ($row) {
+            DB::table('spice_stock_movements')->insert([
+                'spice_id'    => $row->spice_id,
+                'amount'      => $row->amount,
+                'source_type' => 'delivery',
+                'source_id'   => $row->id,
+                'description' => 'Lieferung',
+                'created_at'  => $row->created_at,
+                'updated_at'  => $row->updated_at,
+            ]);
+        });
+
+        // Bestehende Chargen als Bewegungen einlesen
+        DB::table('batches')->orderBy('id')->each(function ($batch) {
+            $spices = DB::table('recipes_spices')->where('recipe_id', $batch->recipe_id)->get();
+            foreach ($spices as $pivot) {
+                $grams = $batch->quantity_g * $pivot->amount_in_percent / 100;
+                DB::table('spice_stock_movements')->insert([
+                    'spice_id'    => $pivot->spice_id,
+                    'amount'      => -$grams,
+                    'source_type' => 'batch',
+                    'source_id'   => $batch->id,
+                    'description' => 'Charge ' . $batch->lot_number,
+                    'created_at'  => $batch->created_at,
+                    'updated_at'  => $batch->updated_at,
+                ]);
+            }
+        });
+
+        // Bestand aller Rohstoffe aus den Bewegungen neu berechnen
+        DB::table('spices')->orderBy('id')->each(function ($spice) {
+            $balance = DB::table('spice_stock_movements')
+                ->where('spice_id', $spice->id)
+                ->sum('amount');
+            DB::table('spices')->where('id', $spice->id)->update(['quantity' => $balance]);
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('spice_stock_movements');
+    }
+};