feat: Establish one-to-many relationship between lecturers and courses, adding UI fields and table columns for assignment and display.

app/Filament/Resources/Master/Courses/CourseResource.php

@@ -12,6 +12,7 @@
 use App\Models\Course;
 use BackedEnum;
 use Filament\Actions\BulkActionGroup;
+use Filament\Forms\Components\Select;
 use Filament\Forms\Components\TextInput;
 use Filament\Resources\Resource;
 use Filament\Schemas\Schema;
@@ -80,6 +81,15 @@ public static function form(Schema $schema): Schema
                     ->maxValue(8)
                     ->helperText('Semester ke berapa mata kuliah ini diajarkan (1-8).'),
 
+                Select::make('lecturer_id')
+                    ->label('Dosen Pengampu')
+                    ->placeholder('Pilih Dosen')
+                    ->relationship('lecturer', 'full_name')
+                    ->preload()
+                    ->searchable()
+                    ->helperText('Pilih dosen yang mengampu mata kuliah ini.')
+                    ->required(),
+
             ])
             ->columns(1);
     }
@@ -101,6 +111,10 @@ public static function table(Table $table): Table
                     ->label('SKS')
                     ->sortable(),
 
+                TextColumn::make('lecturer.full_name')
+                    ->label('Dosen Pengampu')
+                    ->searchable(),
+
                 ...TimestampColumns::make(),
             ])
             ->filters([

app/Filament/Resources/Master/Lecturers/Schemas/LecturerForm.php

@@ -3,9 +3,11 @@
 namespace App\Filament\Resources\Master\Lecturers\Schemas;
 
 use App\Enums\Sex;
+use App\Models\Course;
 use Carbon\Carbon;
 use Filament\Forms\Components\DatePicker;
 use Filament\Forms\Components\Radio;
+use Filament\Forms\Components\Select;
 use Filament\Forms\Components\Textarea;
 use Filament\Forms\Components\TextInput;
 use Filament\Schemas\Components\Grid;
@@ -115,6 +117,29 @@ public static function configure(Schema $schema): Schema
                             ->columnSpanFull(),
                     ])
                     ->columns(2),
+
+                Section::make('Mata Kuliah')
+                    ->description('Daftar mata kuliah yang diampu oleh dosen ini.')
+                    ->schema([
+                        Select::make('courses')
+                            ->label('Mata Kuliah')
+                            ->multiple()
+                            ->relationship('courses', 'name')
+                            ->options(function () {
+                                return Course::all()
+                                    ->groupBy('semester')
+                                    ->mapWithKeys(function ($courses, $semester) {
+                                        return [
+                                            "Semester $semester" => $courses->pluck('name', 'id')->toArray(),
+                                        ];
+                                    })
+                                    ->toArray();
+                            })
+                            ->searchable()
+                            ->preload()
+                            ->live()
+                            ->required(),
+                    ]),
             ])
             ->columns(1);
     }

app/Filament/Resources/Master/Lecturers/Tables/LecturersTable.php

@@ -77,6 +77,12 @@ public static function configure(Table $table): Table
                     ->label('Alamat')
                     ->limit(50),
 
+                TextColumn::make('courses.name')
+                    ->label('Mata Kuliah')
+                    ->badge()
+                    ->searchable()
+                    ->listWithLineBreaks(),
+
                 ...TimestampColumns::make(),
             ])
             ->filters([
@@ -85,6 +91,12 @@ public static function configure(Table $table): Table
                     ->options(Sex::class)
                     ->native(false),
 
+                SelectFilter::make('courses')
+                    ->label('Mata Kuliah')
+                    ->relationship('courses', 'name')
+                    ->multiple()
+                    ->preload(),
+
                 TrashedFilter::make()
                     ->native(false),
             ])

app/Models/Course.php

@@ -4,6 +4,7 @@
 
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\SoftDeletes;
 
 class Course extends Model
@@ -11,4 +12,9 @@ class Course extends Model
     use HasFactory, SoftDeletes;
 
     protected $guarded = ['id'];
+
+    public function lecturer(): BelongsTo
+    {
+        return $this->belongsTo(Lecturer::class);
+    }
 }

app/Models/Lecturer.php

@@ -8,6 +8,7 @@
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Database\Eloquent\SoftDeletes;
 
 class Lecturer extends Model
@@ -40,4 +41,9 @@ public function user(): BelongsTo
     {
         return $this->belongsTo(User::class);
     }
+
+    public function courses(): HasMany
+    {
+        return $this->hasMany(Course::class);
+    }
 }

database/migrations/2026_02_25_024503_create_courses_table.php

@@ -13,6 +13,7 @@ public function up(): void
     {
         Schema::create('courses', function (Blueprint $table) {
             $table->id();
+            $table->foreignId('lecturer_id')->nullable()->constrained()->nullOnDelete();
             $table->string('code', 20)->unique();
             $table->string('name', 100);
             $table->integer('credit')->default(3);