<?php

declare(strict_types=1);

namespace App\Services\Badges;

use App\Models\Student;
use App\Models\StudentClass;

class BadgeStudentLookupService
{
    public function __construct(
        protected BadgeTextFormatter $formatter
    ) {
    }

    /**
     * Load students for badge printing: valid school_id (QR payload), ordered by name.
     *
     * @param  int[]  $studentIds
     * @return array<int, array{student_id:int, fullname:string, grade:string, academic_year:string, school_id:string}>
     */
    public function fetchForBadges(array $studentIds, ?string $schoolYear): array
    {
        $studentIds = $this->formatter->normalizeIds($studentIds);
        if ($studentIds === []) {
            return [];
        }

        $rows = Student::query()
            ->whereIn('id', $studentIds)
            ->where('is_active', 1)
            ->orderBy('lastname')
            ->orderBy('firstname')
            ->get();

        $out = [];
        foreach ($rows as $student) {
            $schoolId = trim((string) ($student->school_id ?? ''));
            if ($schoolId === '' || !preg_match('/^[A-Za-z0-9_-]+$/', $schoolId)) {
                continue;
            }

            $fullname = Student::getFullName($student->toArray());
            $grade = $this->resolveGrade((int) $student->id, (string) ($student->registration_grade ?? ''));

            $academicYear = $schoolYear ?? (string) ($student->school_year ?? '');
            $academicYear = $this->formatter->norm($academicYear);

            $out[] = [
                'student_id' => (int) $student->id,
                'fullname' => $fullname !== '' ? $fullname : 'Student',
                'grade' => $grade,
                'academic_year' => $academicYear,
                'school_id' => $schoolId,
            ];
        }

        return $out;
    }

    protected function resolveGrade(int $studentId, string $registrationGrade): string
    {
        $registrationGrade = $this->formatter->norm($registrationGrade);
        if ($registrationGrade !== '') {
            return $registrationGrade;
        }

        try {
            $g = StudentClass::getStudentGrade($studentId);
            $g = $this->formatter->norm((string) $g);

            return $g !== '' ? $g : '—';
        } catch (\Throwable) {
            return '—';
        }
    }
}