<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use App\Models\QuestionnaireQuestion;
use App\Models\QuestionnaireSet;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;

class QuestionController extends Controller
{
    public function store(Request $request, QuestionnaireSet $set): RedirectResponse
    {
        if ($request->has('options')) {
            $request->merge(['options' => array_values(array_filter($request->input('options', [])))]);
        }

        $data = $request->validate([
            'question_text'   => 'required|string|max:1000',
            'question_type'   => 'required|in:tajuk,rating,single_choice,multiple_choice,short_text,long_text',
            'is_required'     => 'boolean',
            'parent_id'       => 'nullable|integer|exists:questionnaire_questions,id',
            'options'         => 'nullable|array',
            'options.*'       => 'required|string|max:255',
            'rating_labels'   => 'nullable|array',
            'rating_labels.*' => 'nullable|string|max:100',
        ]);

        if ($data['question_type'] === 'rating') {
            if (empty($data['parent_id'])) {
                return back()->withErrors(['parent_id' => 'Soalan rating mesti diletakkan di bawah tajuk.'])->withInput();
            }
            $parent = QuestionnaireQuestion::find($data['parent_id']);
            if (! $parent || $parent->question_type !== 'tajuk') {
                return back()->withErrors(['parent_id' => 'Parent mesti jenis Tajuk.'])->withInput();
            }
        }

        $needsOptions = in_array($data['question_type'], ['single_choice', 'multiple_choice']);
        if ($needsOptions && empty($data['options'])) {
            return back()->withErrors(['options' => 'Pilihan jawapan diperlukan untuk jenis soalan ini.'])->withInput();
        }

        $parentId = $data['question_type'] === 'rating' ? ($data['parent_id'] ?? null) : null;

        $maxOrder = $set->questions()
            ->when($parentId,
                fn($q) => $q->where('parent_id', $parentId),
                fn($q) => $q->whereNull('parent_id')
            )
            ->max('sort_order') ?? 0;

        $ratingLabels = null;
        if ($data['question_type'] === 'tajuk') {
            $filtered = array_filter($data['rating_labels'] ?? [], fn($v) => $v !== null && $v !== '');
            $ratingLabels = ! empty($filtered) ? $filtered : null;
        }

        $set->questions()->create([
            'question_text' => $data['question_text'],
            'question_type' => $data['question_type'],
            'parent_id'     => $parentId,
            'is_required'   => $data['question_type'] === 'tajuk' ? false : ($data['is_required'] ?? true),
            'options_json'  => $needsOptions ? array_values(array_filter($data['options'] ?? [])) : null,
            'rating_labels' => $ratingLabels,
            'sort_order'    => $maxOrder + 1,
        ]);

        return redirect()->route('admin.questionnaires.show', $set)
            ->with('success', 'Soalan berjaya ditambah.');
    }

    public function update(Request $request, QuestionnaireQuestion $question): RedirectResponse
    {
        if ($request->has('options')) {
            $request->merge(['options' => array_values(array_filter($request->input('options', [])))]);
        }

        $data = $request->validate([
            'question_text'   => 'required|string|max:1000',
            'question_type'   => 'required|in:tajuk,rating,single_choice,multiple_choice,short_text,long_text',
            'is_required'     => 'boolean',
            'parent_id'       => 'nullable|integer|exists:questionnaire_questions,id',
            'options'         => 'nullable|array',
            'options.*'       => 'required|string|max:255',
            'rating_labels'   => 'nullable|array',
            'rating_labels.*' => 'nullable|string|max:100',
        ]);

        if ($data['question_type'] === 'rating') {
            if (empty($data['parent_id'])) {
                return back()->withErrors(['parent_id' => 'Soalan rating mesti diletakkan di bawah tajuk.'])->withInput();
            }
            $parent = QuestionnaireQuestion::find($data['parent_id']);
            if (! $parent || $parent->question_type !== 'tajuk') {
                return back()->withErrors(['parent_id' => 'Parent mesti jenis Tajuk.'])->withInput();
            }
        }

        $needsOptions = in_array($data['question_type'], ['single_choice', 'multiple_choice']);

        $parentId = $data['question_type'] === 'rating' ? ($data['parent_id'] ?? null) : null;

        $ratingLabels = null;
        if ($data['question_type'] === 'tajuk') {
            $filtered = array_filter($data['rating_labels'] ?? [], fn($v) => $v !== null && $v !== '');
            $ratingLabels = ! empty($filtered) ? $filtered : null;
        }

        $question->update([
            'question_text' => $data['question_text'],
            'question_type' => $data['question_type'],
            'parent_id'     => $parentId,
            'is_required'   => $data['question_type'] === 'tajuk' ? false : ($data['is_required'] ?? true),
            'options_json'  => $needsOptions ? array_values(array_filter($data['options'] ?? [])) : null,
            'rating_labels' => $ratingLabels,
        ]);

        return redirect()->route('admin.questionnaires.show', $question->questionnaire_set_id)
            ->with('success', 'Soalan berjaya dikemaskini.');
    }

    public function destroy(QuestionnaireQuestion $question): RedirectResponse
    {
        $setId = $question->questionnaire_set_id;

        // Cascade-delete children if this is a tajuk (DB cascade handles it too, but be explicit)
        if ($question->question_type === 'tajuk') {
            $question->children()->delete();
        }

        $question->delete();

        return redirect()->route('admin.questionnaires.show', $setId)
            ->with('success', 'Soalan berjaya dipadam.');
    }

    public function reorder(Request $request): JsonResponse
    {
        $data = $request->validate([
            'order'     => 'required|array',
            'order.*'   => 'integer|exists:questionnaire_questions,id',
            'parent_id' => 'nullable|integer|exists:questionnaire_questions,id',
        ]);

        foreach ($data['order'] as $sortOrder => $questionId) {
            QuestionnaireQuestion::where('id', $questionId)
                ->update(['sort_order' => $sortOrder + 1]);
        }

        return response()->json(['ok' => true]);
    }
}