<?php

namespace App\Http\Controllers;

use App\Models\Disease;
use App\Models\Notification;
use App\Models\Symptom;
use App\Models\Treatment;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Facades\DB;

class DiseaseController extends Controller
{
    // Helper untuk simpan foto langsung ke public/storage
    private function savePhoto($file, $folder)
    {
        $filename = uniqid() . '_' . time() . '.' . $file->getClientOriginalExtension();
        $file->move(public_path('storage/' . $folder), $filename);
        return $folder . '/' . $filename;
    }

    private function deletePhoto($path)
    {
        $fullPath = public_path('storage/' . $path);
        if (file_exists($fullPath)) {
            unlink($fullPath);
        }
    }

    public function index()
    {
        $diseases = Disease::with(['symptoms','treatments'])->get();
        return view('diseases.index', compact('diseases'));
    }

    public function create()
    {
        $nextDiseaseCode   = 'P' . str_pad(Disease::count() + 1, 2, '0', STR_PAD_LEFT);
        $nextSymptomCode   = 'G' . str_pad(Symptom::count() + 1, 2, '0', STR_PAD_LEFT);
        $nextTreatmentCode = 'S' . str_pad(Treatment::count() + 1, 2, '0', STR_PAD_LEFT);

        return view('diseases.create', compact(
            'nextDiseaseCode',
            'nextSymptomCode',
            'nextTreatmentCode'
        ));
    }

    public function edit(Disease $disease)
    {
        $disease->load(['symptoms','treatments']);

        return view('diseases.create', [
            'disease'         => $disease,
            'isEdit'          => true,
            'nextDiseaseCode' => $disease->code,
        ]);
    }

    public function update(Request $request, Disease $disease)
    {
        $request->validate([
            'name'        => 'required|string|max:255',
            'latin_name'  => 'nullable|string|max:255',
            'description' => 'nullable|string',
        ]);

        DB::transaction(function () use ($request, $disease) {

            $disease->update([
                'name'        => $request->name,
                'latin_name'  => $request->latin_name,
                'description' => $request->description,
            ]);

            // Handle foto penyakit
            if ($request->hasFile('photo')) {
                if ($disease->photo) {
                    $this->deletePhoto($disease->photo);
                }
                $disease->update(['photo' => $this->savePhoto($request->file('photo'), 'diseases')]);
            }

            // RESET RELASI
            $disease->symptoms()->detach();
            $disease->treatments()->delete();

            // SYMPTOMS
            foreach ($request->symptoms as $i => $s) {
                if (empty($s['name'])) continue;

                $symptomPhoto = null;
                if (isset($s['photo']) && $s['photo'] instanceof \Illuminate\Http\UploadedFile) {
                    $symptomPhoto = $this->savePhoto($s['photo'], 'symptoms');
                }

                $symptom = Symptom::where('name', $s['name'])->first();
                if (!$symptom) {
                    $symptom = Symptom::create([
                        'code'  => 'G' . str_pad(Symptom::count() + 1, 2, '0', STR_PAD_LEFT),
                        'name'  => $s['name'],
                        'photo' => $symptomPhoto,
                    ]);
                }

                $disease->symptoms()->attach($symptom->id, ['cf_value' => $s['cf'] ?? 0.7]);
            }

            // TREATMENTS
            $maxRow = DB::select('SELECT MAX(CAST(SUBSTRING(code, 2) AS UNSIGNED)) as maxnum FROM treatments')[0];
            $lastNum = $maxRow->maxnum ?? 0;

            foreach ($request->treatments as $i => $t) {
                if (!isset($t['description']) || trim($t['description']) === '') continue;

                $lastNum++;
                DB::table('treatments')->insert([
                    'code'        => 'S' . str_pad($lastNum, 2, '0', STR_PAD_LEFT),
                    'disease_id'  => $disease->id,
                    'description' => trim($t['description']),
                    'order'       => $i + 1,
                    'created_at'  => now(),
                    'updated_at'  => now(),
                ]);
            }
        });

        return redirect()->route('diseases.show', $disease->id)
            ->with('status', 'Penyakit berhasil diupdate!');
    }

    public function store(Request $request)
    {
        $request->validate([
            'name'                     => 'required|string|max:255',
            'latin_name'               => 'nullable|string|max:255',
            'description'              => 'nullable|string',
            'photo'                    => 'nullable|image|mimes:jpg,jpeg,png|max:3072',
            'symptoms'                 => 'required|array|min:3',
            'symptoms.*.name'          => 'required|string',
            'treatments'               => 'required|array|min:3',
            'treatments.*.description' => 'nullable|string',
        ]);

        $disease = DB::transaction(function () use ($request) {

            $photoPath = null;
            if ($request->hasFile('photo')) {
                $photoPath = $this->savePhoto($request->file('photo'), 'diseases');
            }

            $disease = Disease::create([
                'code'        => 'P' . str_pad(Disease::count() + 1, 2, '0', STR_PAD_LEFT),
                'name'        => $request->name,
                'latin_name'  => $request->latin_name,
                'description' => $request->description,
                'photo'       => $photoPath,
            ]);

            // SYMPTOMS
            foreach ($request->symptoms as $s) {
                if (empty($s['name'])) continue;

                $symptomPhoto = null;
                if (isset($s['photo']) && $s['photo'] instanceof \Illuminate\Http\UploadedFile) {
                    $symptomPhoto = $this->savePhoto($s['photo'], 'symptoms');
                }

                $symptom = Symptom::where('name', $s['name'])->first();
                if (!$symptom) {
                    $symptom = Symptom::create([
                        'code'  => 'G' . str_pad(Symptom::count() + 1, 2, '0', STR_PAD_LEFT),
                        'name'  => $s['name'],
                        'photo' => $symptomPhoto,
                    ]);
                }

                $disease->symptoms()->attach(
                    $symptom->id,
                    ['cf_value' => $s['cf'] ?? 0.7]
                );
            }

            // TREATMENTS
            if ($request->has('treatments')) {
                $maxRow = DB::select('SELECT MAX(CAST(SUBSTRING(code, 2) AS UNSIGNED)) as maxnum FROM treatments')[0];
                $lastNum = $maxRow->maxnum ?? 0;

                foreach ($request->treatments as $i => $t) {
                    if (!isset($t['description']) || trim($t['description']) === '') continue;

                    $lastNum++;
                    DB::table('treatments')->insert([
                        'code'        => 'S' . str_pad($lastNum, 2, '0', STR_PAD_LEFT),
                        'disease_id'  => $disease->id,
                        'description' => trim($t['description']),
                        'order'       => $i + 1,
                        'created_at'  => now(),
                        'updated_at'  => now(),
                    ]);
                }
            }

            return $disease;
        });

        Notification::create([
            'user_id' => auth()->id(),
            'type'    => 'system',
            'title'   => 'Penyakit Baru Ditambahkan',
            'message' => "Penyakit \"{$disease->name}\" ({$disease->code}) berhasil ditambahkan dengan "
                        . $disease->symptoms()->count() . " gejala.",
            'is_read' => false,
        ]);

        return redirect()->route('diseases.index')
            ->with('status', 'Penyakit berhasil ditambahkan!');
    }

    public function show(Disease $disease)
    {
        $disease->load(['symptoms','treatments']);
        return view('diseases.show', compact('disease'));
    }

    public function destroy(Disease $disease)
    {
        $diseaseName  = $disease->name;
        $diseaseCode  = $disease->code;

        DB::transaction(function () use ($disease) {

            if ($disease->photo) {
                $this->deletePhoto($disease->photo);
            }

            foreach ($disease->symptoms as $symptom) {
                $usedByOthers = $symptom->diseases()
                    ->where('diseases.id', '!=', $disease->id)
                    ->exists();

                if (!$usedByOthers) {
                    if ($symptom->photo) {
                        $this->deletePhoto($symptom->photo);
                    }
                    $symptom->delete();
                }
            }

            $disease->symptoms()->detach();
            $disease->treatments()->delete();
            $disease->delete();
        });

        Notification::create([
            'user_id' => auth()->id(),
            'type'    => 'system',
            'title'   => 'Penyakit Dihapus',
            'message' => "Penyakit \"{$diseaseName}\" ({$diseaseCode}) telah dihapus.",
            'is_read' => false,
        ]);

        return redirect()->route('diseases.index')
            ->with('status', 'Penyakit berhasil dihapus!');
    }
}