Take deductible VAT into account for tax calculations

app/Filament/Resources/ExpenseResource.php

@@ -8,6 +8,7 @@
 use Closure;
 use Illuminate\Support\Arr;
 use Illuminate\Support\Facades\Storage;
+use Illuminate\Support\Number;
 use Filament\Actions\Action;
 use Filament\Actions\ActionGroup;
 use Filament\Actions\BulkActionGroup;
@@ -73,8 +74,18 @@ public static function table(Table $table): Table
                     ->label(__('vat'))
                     ->money('eur')
                     ->fontFamily(FontFamily::Mono)
-                    ->state(fn(Expense $record): float => $record->vat)
-                    ->color(fn(string $state): string => $state == 0 ? 'gray' : 'normal')
+                    ->state(fn(Expense $record): float => $record->deductibleVat)
+                    ->color(fn(Expense $record): string => match (true) {
+                        $record->taxable_ratio < 1 => 'warning',
+                        $record->deductibleVat == 0 => 'gray',
+                        default => 'normal',
+                    })
+                    ->tooltip(fn(Expense $record): ?string => $record->taxable_ratio < 1
+                        ? __('taxableRatioTooltip', [
+                            'ratio' => Number::percentage($record->taxable_ratio * 100),
+                            'vat' => Number::currency($record->vat, 'eur'),
+                        ])
+                        : null)
                     ->sortable(),
                 TextColumn::make('quantity')
                     ->label(__('quantity'))

app/Filament/Widgets/MinorAssetsList.php

@@ -14,6 +14,7 @@
 use Filament\Widgets\TableWidget;
 use Illuminate\Support\Collection;
 use Illuminate\Support\Facades\Storage;
+use Illuminate\Support\Number;
 
 class MinorAssetsList extends TableWidget
 {
@@ -60,8 +61,18 @@ public function table(Table $table): Table
                     ->label(__('vat'))
                     ->money('eur')
                     ->fontFamily(FontFamily::Mono)
-                    ->state(fn(Expense $record): float => $record->vat)
-                    ->color(fn(string $state): string => $state == 0 ? 'gray' : 'normal')
+                    ->state(fn(Expense $record): float => $record->deductibleVat)
+                    ->color(fn(Expense $record): string => match (true) {
+                        $record->taxable_ratio < 1 => 'warning',
+                        $record->deductibleVat == 0 => 'gray',
+                        default => 'normal',
+                    })
+                    ->tooltip(fn(Expense $record): ?string => $record->taxable_ratio < 1
+                        ? __('taxableRatioTooltip', [
+                            'ratio' => Number::percentage($record->taxable_ratio * 100),
+                            'vat' => Number::currency($record->vat, 'eur'),
+                        ])
+                        : null)
                     ->sortable(),
                 TextColumn::make('net')
                     ->label(__('net'))

app/Models/Expense.php

@@ -76,7 +76,7 @@ public static function ofTime(Carbon $d, TimeUnit $u, ?ExpenseCategory $category
             ->whereIn('category', $categories)
             ->get();
         $net = array_sum($records->map(fn(self $r) => $r->deductibleNet)->toArray());
-        $vat = array_sum($records->map(fn(self $r) => $r->vat)->toArray());
+        $vat = array_sum($records->map(fn(self $r) => $r->deductibleVat)->toArray());
         return [$net, $vat];
     }
 
@@ -136,4 +136,12 @@ protected function deductibleNet(): Attribute
     {
         return Attribute::make(fn(): float => round($this->net * $this->taxable_ratio, 2));
     }
+
+    /**
+     * Vat amount of this expense that is actually deductible, pro-rated by taxable_ratio
+     */
+    protected function deductibleVat(): Attribute
+    {
+        return Attribute::make(fn(): float => round($this->vat * $this->taxable_ratio, 2));
+    }
 }

lang/de.json

@@ -215,6 +215,7 @@
     "sumWorkingHoursPerYear": "Summe bezahlter Arbeitsstunden pro Jahr",
     "taxable": "Versteuert",
     "taxableRatio": "Abzugsfähiger Anteil",
+    "taxableRatioTooltip": "Anteilig :ratio von :vat USt.",
     "taxes": "Steuern",
     "taxOffice": "Finanzamt",
     "taxReport": "Steuererklärung",

lang/en.json

@@ -215,6 +215,7 @@
     "sumWorkingHoursPerYear": "Sum of paid working hours per year",
     "taxable": "Taxable",
     "taxableRatio": "Deductible share",
+    "taxableRatioTooltip": "Pro-rated to :ratio of :vat VAT",
     "taxes": "Taxes",
     "taxOffice": "Tax office",
     "taxReport": "Tax return",

tests/Feature/ExpenseResourceTest.php

@@ -49,6 +49,23 @@ public function it_lists_expenses_in_the_table(): void
             ->assertCanSeeTableRecords($expenses);
     }
 
+    #[Test]
+    public function it_shows_the_pro_rated_vat_in_the_table(): void
+    {
+        $this->actingAs(User::factory()->create());
+        $expense = Expense::factory()->create([
+            'price' => 100,
+            'quantity' => 1,
+            'taxable' => true,
+            'vat_rate' => 0.19,
+            'taxable_ratio' => 0.5,
+        ]);
+
+        Livewire::test(ListExpenses::class, ['activeTab' => 'all'])
+            ->loadTable()
+            ->assertTableColumnStateSet('vat', 7.99, $expense);
+    }
+
     #[Test]
     public function it_creates_an_expense(): void
     {

tests/Feature/MinorAssetsListTest.php

@@ -127,6 +127,26 @@ public function it_only_lists_minor_assets_expenses_from_the_selected_year(): vo
         $this->assertTrue($records->contains($inYear));
     }
 
+    #[Test]
+    public function it_shows_the_pro_rated_vat_in_the_table(): void
+    {
+        $this->actingAs(User::factory()->create());
+        $year = now()->year - 1;
+        $expense = Expense::factory()->create([
+            'expended_at' => "$year-06-01",
+            'category' => ExpenseCategory::MinorAssets,
+            'price' => 500,
+            'quantity' => 1,
+            'taxable' => true,
+            'vat_rate' => 0.19,
+            'taxable_ratio' => 0.5,
+        ]);
+
+        Livewire::test(MinorAssetsList::class)
+            ->loadTable()
+            ->assertTableColumnStateSet('vat', round($expense->vat * 0.5, 2), $expense);
+    }
+
     #[Test]
     public function it_hides_the_bill_download_until_a_document_exists(): void
     {

tests/Feature/TaxOverviewTest.php

@@ -60,6 +60,26 @@ public function it_summarizes_taxable_net_and_vat_for_the_current_month(): void
         $this->assertSame(174.03, $record['totalVat']);
     }
 
+    #[Test]
+    public function it_pro_rates_the_expense_vat_by_taxable_ratio(): void
+    {
+        Expense::factory()->create([
+            'expended_at' => now(),
+            'category' => ExpenseCategory::Good,
+            'price' => 100,
+            'quantity' => 1,
+            'taxable' => true,
+            'vat_rate' => 0.19,
+            'taxable_ratio' => 0.5,
+        ]);
+
+        $widget = new TaxOverview();
+        $record = $widget->getTableRecords()->first();
+
+        $this->assertSame(7.99, $record['vatExpenses']);
+        $this->assertSame(-7.99, $record['totalVat']);
+    }
+
     #[Test]
     public function it_disables_the_last_advance_vat_action_when_it_already_exists(): void
     {

tests/Feature/TaxReturnFormInputTest.php

@@ -129,6 +129,29 @@ public function it_computes_the_tax_return_lines_for_the_selected_year(): void
         $this->assertSame(161.0, $records[1]['value']); // itr1 - taxable profit, rounded to whole euros for Elster (raw value is 160.76)
     }
 
+    #[Test]
+    public function it_pro_rates_expense_vat_by_taxable_ratio(): void
+    {
+        $year = now()->year - 1;
+
+        Expense::factory()->create([
+            'expended_at' => "$year-06-01",
+            'category' => ExpenseCategory::Good,
+            'price' => 100,
+            'quantity' => 1,
+            'taxable' => true,
+            'vat_rate' => 0.19,
+            'taxable_ratio' => 0.5,
+        ]);
+
+        $widget = new TaxReturnFormInput();
+        $widget->filter = $year;
+        $records = $widget->getTableRecords()->keyBy('__key');
+
+        $this->assertSame(7.99, $records[11]['value']); // rsc57 - vat expended, pro-rated by taxable_ratio
+        $this->assertSame(-7.99, $records[14]['value']); // vr118 - vat payable, must reflect the pro-rated vat
+    }
+
     #[Test]
     public function it_rounds_the_final_profit_line_to_cents_despite_floating_point_noise(): void
     {

tests/Unit/Models/ExpenseTest.php

@@ -82,6 +82,30 @@
     expect($expense->deductibleNet)->toBe($expense->net);
 });
 
+it('pro-rates the deductible vat amount by taxable_ratio', function () {
+    $expense = Expense::factory()->create([
+        'price' => 100,
+        'quantity' => 1,
+        'taxable' => true,
+        'vat_rate' => 0.19,
+        'taxable_ratio' => 0.5,
+    ]);
+
+    expect($expense->vat)->toBe(15.97)
+        ->and($expense->deductibleVat)->toBe(7.99);
+});
+
+it('leaves the deductible vat amount unchanged when taxable_ratio is 1', function () {
+    $expense = Expense::factory()->create([
+        'price' => 100,
+        'quantity' => 1,
+        'taxable' => true,
+        'vat_rate' => 0.19,
+    ])->refresh();
+
+    expect($expense->deductibleVat)->toBe($expense->vat);
+});
+
 it('calculates gross, net and vat amounts based on price, quantity and vat rate', function () {
     $expense = Expense::factory()->create([
         'price' => 100,
@@ -201,7 +225,7 @@
         ->and($vat)->toBe(0.0);
 });
 
-it('sums the deductible net amount honoring taxable_ratio within a time range', function () {
+it('sums the deductible net and vat amounts honoring taxable_ratio within a time range', function () {
     $month = Carbon::parse('2026-03-15');
 
     Expense::factory()->create([
@@ -214,7 +238,8 @@
         'category' => ExpenseCategory::Good,
     ]);
 
-    [$net] = Expense::ofTime($month, TimeUnit::MONTH, ExpenseCategory::Good);
+    [$net, $vat] = Expense::ofTime($month, TimeUnit::MONTH, ExpenseCategory::Good);
 
-    expect($net)->toBe(42.02);
+    expect($net)->toBe(42.02)
+        ->and($vat)->toBe(7.99);
 });