Build the stuff for payments.

app/Http/Controllers/Api/InvoiceController.php

@@ -19,6 +19,11 @@ class InvoiceController extends Controller
         return response()->json(Invoice::whereBetween('created_at', [$from, $end])->with('address')->orderBy('created_at', 'desc')->get());
     }
 
+    public function open(): JsonResponse
+    {
+        return response()->json(Invoice::where('status', '=', 'sent')->orderBy('created_at', 'desc')->with(['customer', 'address', 'payments'])->get());
+    }
+
     /**
      * Store a newly created resource in storage.
      */

app/Http/Controllers/Api/PaymentController.php

@@ -0,0 +1,82 @@
+<?php
+
+namespace App\Http\Controllers\Api;
+
+use App\Http\Controllers\Controller;
+use App\Models\Invoice;
+use App\Models\Payment;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Http\Request;
+
+class PaymentController extends Controller
+{
+    /**
+     * Display a listing of the resource.
+     */
+    public function indexFilter($from = null, $end = null): JsonResponse
+    {
+        return response()->json(Payment::whereBetween('payment_date', [$from, $end])->with(['invoice'])->orderBy('payment_date', 'desc')->get());
+    }
+
+    public function index(Invoice $invoice): JsonResponse
+    {
+        return response()->json($invoice->payments);
+    }
+
+    /**
+     * Store a newly created resource in storage.
+     */
+    public function store(Request $request, Invoice $invoice): JsonResponse
+    {
+        $paymentData = $request->validate([
+            'invoice_id' => 'required|integer|exists:invoices,id',
+            'paid_amount' => 'required|numeric',
+            'payment_date' => 'required|date',
+            'payment_method' => 'nullable|string',
+            'status' => 'required|string|in:full,partial',
+        ]);
+
+        if ($paymentData['status'] == 'full') {
+            $invoice->update(['status' => 'paid']);
+        }
+
+        return response()->json($invoice->payments()->create($request->all()));
+    }
+
+    /**
+     * Display the specified resource.
+     */
+    public function show(Payment $payment)
+    {
+        //
+    }
+
+    /**
+     * Update the specified resource in storage.
+     */
+    public function update(Request $request, Payment $payment): JsonResponse
+    {
+        $paymentData = $request->validate([
+            'invoice_id' => 'required|integer|exists:invoices,id',
+            'paid_amount' => 'required|numeric',
+            'payment_date' => 'required|date',
+            'payment_method' => 'nullable|string',
+            'status' => 'required|string|in:full,partial',
+        ]);
+
+        $payment->update($paymentData);
+        if ($payment->invoice->payments->where('status', 'full')->count() === 0) {
+            $payment->invoice->update(['status' => 'sent']);
+        }
+
+        return response()->json($payment);
+    }
+
+    /**
+     * Remove the specified resource from storage.
+     */
+    public function destroy(Payment $payment)
+    {
+        //
+    }
+}

app/Http/Controllers/PaymentController.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace App\Http\Controllers;
+
+use App\Models\Payment;
+use Illuminate\Contracts\View\View;
+use Illuminate\Http\Request;
+
+class PaymentController extends Controller
+{
+    /**
+     * Display a listing of the resource.
+     */
+    public function index(): View
+    {
+        return view('payment.index');
+    }
+
+    /**
+     * Show the form for creating a new resource.
+     */
+    public function create(): View
+    {
+        return view('payment.create');
+    }
+
+    /**
+     * Show the form for editing the specified resource.
+     */
+    public function edit(Payment $payment): View
+    {
+        return view('payment.edit', ['payment' => $payment->load('invoice')]);
+    }
+
+}

app/Models/Invoice.php

@@ -38,8 +38,6 @@ class Invoice extends Model
 
     /**
      * Get the invoice state as translated string.
-     *
-     * @return string
      */
     public function getLocalizedStateAttribute(): string
     {
@@ -56,35 +54,57 @@ class Invoice extends Model
 
     /**
      * Get the created_at attribute in local time format.
-     *
-     * @return string
      */
     public function getCreatedAttribute(): string
     {
         return $this->created_at->format('d.m.Y');
     }
+
+    /**
+     * Get the user, that has created the invoice.
+     */
     public function user(): BelongsTo
     {
         return $this->belongsTo(User::class);
     }
 
+    /**
+     * Get the invoice's customer.
+     */
     public function customer(): BelongsTo
     {
         return $this->belongsTo(Customer::class);
     }
 
+    /**
+     * Get the invoice's address.
+     */
     public function address(): BelongsTo
     {
         return $this->belongsTo(Address::class)->withTrashed();
     }
 
+    /**
+     * Get the invoice's delivery address.
+     */
     public function delivery(): BelongsTo
     {
         return $this->belongsTo(Address::class)->withTrashed();
     }
 
+    /**
+     * Get the items (invoice positions) of this invoice.
+     */
     public function items(): HasMany
     {
         return $this->hasMany(Invoiceitem::class);
     }
+
+    /**
+     * Get the payments for the invoice
+     */
+    public function payments(): HasMany
+    {
+        return $this->hasMany(Payment::class);
+    }
 }

app/Models/Payment.php

@@ -3,9 +3,58 @@
 namespace App\Models;
 
 use Illuminate\Database\Eloquent\Model;
-use Illuminate\Database\Eloquent\SoftDeletes;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Support\Facades\Date;
 
 class Payment extends Model
 {
-    use SoftDeletes;
+    public $timestamps = false;
+
+    /**
+     * The attributes that are mass assignable.
+     *
+     * @var array<int, string>
+     */
+    protected $fillable = [
+        'invoice_id',
+        'paid_amount',
+        'status',
+        'payment_method',
+        'payment_date',
+    ];
+
+    /**
+     * The attributes that are appended with attribute getters.
+     *
+     * @var string[]
+     */
+    protected $appends = [
+        'date',
+        'localized_state'
+    ];
+
+    /**
+     * Get the payment state as translated string.
+     */
+    public function getLocalizedStateAttribute(): string
+    {
+        return __('invoice.Payment state ' . $this->status);
+    }
+
+    /**
+     * Get the payment date as localized string.
+     */
+    public function getDateAttribute(): string
+    {
+        return Date::createFromFormat('Y-m-d', $this->payment_date)->format('d.m.Y');
+    }
+
+    /**
+     * Get the invoice the payment belongs to.
+     */
+    public function invoice(): BelongsTo
+    {
+        return $this->belongsTo(Invoice::class);
+    }
+
 }