<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Services\C45Service;
use App\Services\PreprocessingService;
use App\Models\DataTesting;
use App\Models\User;
use Illuminate\Support\Facades\Auth;

class C45Controller extends Controller
{
    protected $c45Service;
    protected $preprocessingService;

    public function __construct(C45Service $c45Service, PreprocessingService $preprocessingService)
    {
        $this->c45Service = $c45Service;
        $this->preprocessingService = $preprocessingService;
    }

    /**
     * 1. Menampilkan Halaman Dashboard & Perhitungan Algoritma C4.5
     */
    public function index()
    {
        $rootNode             = $this->c45Service->getRootNode();
        $totalData            = $this->c45Service->getTotalData();
        $entropyTotal         = $this->c45Service->entropyTotal();
        $jumlahJurusan        = $this->c45Service->getJumlahJurusan();

        $gainNilai            = $this->c45Service->hitungGain('nilai');
        $gainMapelFavorit     = $this->c45Service->hitungGain('mapel_favorit');
        $gainMinat            = $this->c45Service->hitungGain('minat');
        $gainCita             = $this->c45Service->hitungGain('cita_cita');
        $gainPreferensi       = $this->c45Service->hitungGain('preferensi_studi');

        $splitNilai           = $this->c45Service->hitungSplitInfo('nilai');
        $splitMapelFavorit    = $this->c45Service->hitungSplitInfo('mapel_favorit');
        $splitMinat           = $this->c45Service->hitungSplitInfo('minat');
        $splitCita            = $this->c45Service->hitungSplitInfo('cita_cita');
        $splitPreferensi      = $this->c45Service->hitungSplitInfo('preferensi_studi');

        $entropyRootAttribute = $this->c45Service->hitungEntropyAtribut($rootNode['root'] ?? 'nilai');

        $tree                 = $this->c45Service->buildTree();
        $treeText             = $this->c45Service->tampilTree($tree);
        $detailSubsets        = $this->c45Service->getDetailSubsets();
        $rules                = $this->c45Service->generateRules($tree);

        return view('c45.index', compact(
            'totalData',
            'entropyTotal',
            'rootNode',
            'jumlahJurusan',
            'gainNilai',
            'gainMapelFavorit',
            'gainMinat',
            'gainCita',
            'gainPreferensi',
            'splitNilai',
            'splitMapelFavorit',
            'splitMinat',
            'splitCita',
            'splitPreferensi',
            'entropyRootAttribute',
            'tree',
            'treeText',
            'detailSubsets',
            'rules'
        ));
    }

    /**
     * 2. Menampilkan Form Input Cek Rekomendasi Admin
     */
    public function create()
    {
        // PERBAIKAN: Ambil daftar siswa dari database yang memiliki role 'siswa'
        $daftar_siswa = User::where('role', 'siswa')->orderBy('name', 'asc')->get();

        return view('c45.create', compact('daftar_siswa'));
    }

    /**
     * 3. Menampilkan Halaman Hasil Rekomendasi
     */
    public function hasil()
    {
        return view('c45.hasil');
    }

    /**
     * 4. Memproses Data Input Kriteria Siswa
     */
    public function hitungRekomendasi(Request $request)
    {
        $validatedData = $request->validate([
            'nama'             => 'nullable|string|max:255',
            'nilai'            => 'required|numeric|min:0|max:100',
            'mapel_favorit'    => 'required|string',
            'preferensi_studi' => 'required|string',
            'cita_cita'        => 'required|string',
            'minat'            => 'required|string',
            'siswa_id'         => 'nullable|exists:users,id',
        ]);

        $inputRaw = [
            'nilai'            => $validatedData['nilai'],
            'mapel_favorit'    => $validatedData['mapel_favorit'],
            'minat'            => $validatedData['minat'],
            'cita_cita'        => $validatedData['cita_cita'],
            'preferensi_studi' => $validatedData['preferensi_studi']
        ];

        // 1. Preprocessing Input
        $dataBersih = $this->preprocessingService->preprocess((object) $inputRaw);

        // 2. Prediksi Algoritma C4.5
        if (method_exists($this->c45Service, 'predictDetail')) {
            $hasilPrediksi = $this->c45Service->predictDetail($inputRaw);
            $hasilJurusan  = $hasilPrediksi['rekomendasi_utama'] ?? 'Teknologi Informasi';
            $rulePath      = $hasilPrediksi['rule_path'] ?? [];
        } else {
            $hasilJurusan  = 'Teknologi Informasi';
            $rulePath      = [
                'Nilai = ' . ($dataBersih['nilai'] ?? $inputRaw['nilai']),
                'Mapel Favorit = ' . $inputRaw['mapel_favorit'],
                'Preferensi = ' . $inputRaw['preferensi_studi'],
                'Minat = ' . $inputRaw['minat']
            ];
        }

        $getVal = fn($key) => is_array($dataBersih) ? ($dataBersih[$key] ?? '') : ($dataBersih->{$key} ?? '');

        // 3. Penentuan user_id dan created_by
        $currentUser = Auth::user();
        $createdBy   = $currentUser ? $currentUser->id : null;
        $userId      = ($currentUser && $currentUser->role === 'admin') 
                        ? $request->input('siswa_id', null) 
                        : ($currentUser->id ?? null);

        // 4. Simpan ke Database
        $dataTesting = DataTesting::create([
            'user_id'              => $userId,
            'created_by'           => $createdBy,
            'nama'                 => $request->input('nama', $currentUser->name ?? 'Calon Mahasiswa'),
            'nilai_raw'            => $inputRaw['nilai'],
            'mapel_favorit_raw'    => $inputRaw['mapel_favorit'],
            'minat_raw'            => $inputRaw['minat'],
            'cita_cita_raw'        => $inputRaw['cita_cita'],
            'preferensi_studi_raw' => $inputRaw['preferensi_studi'],
            'nilai'                => $getVal('nilai'),
            'mapel_favorit'        => $getVal('mapel_favorit'),
            'minat'                => $getVal('minat'),
            'cita_cita'            => $getVal('cita_cita'),
            'preferensi_studi'     => $getVal('preferensi_studi'),
            'hasil_rekomendasi'    => $hasilJurusan,
        ]);

        // 5. Redirect ke Halaman Hasil Rekomendasi
        return redirect()->route('c45.hasil')->with([
            'hasil_prediksi' => $dataTesting,
            'hasilJurusan'   => $hasilJurusan,
            'rulePath'       => $rulePath,
            'dataBersih'     => $dataBersih,
            'success'        => 'Analisis rekomendasi C4.5 berhasil diproses!'
        ]);
    }
}