<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;

use function PHPUnit\Framework\isInstanceOf;

class Doubler extends Model
{
    // Specify that we're not using a single primary key
    protected $primaryKey = null;

    public $incrementing = false;

    protected $guarded = [];

    public function student(): BelongsTo
    {
        return $this->belongsTo(Student::class);
    }

    public function event(): BelongsTo
    {
        return $this->belongsTo(Event::class);
    }

    // Find a doubler based on both keys
    public static function findDoubler($studentId, $eventId)
    {
        return static::where('student_id', $studentId)
            ->where('event_id', $eventId)
            ->first();
    }

    /**
     * Sync doubler records for a specified event
     */
    public static function syncForEvent($eventId): void
    {
        if (isInstanceOf(Event::class, $eventId)) {
            $eventId = $eventId->id;
        }

        // Get students with multiple entries in this event's auditions
        $studentsWithMultipleEntries = Student::query()
            ->select('students.id')
            ->join('entries', 'students.id', '=', 'entries.student_id')
            ->join('auditions', 'entries.audition_id', '=', 'auditions.id')
            ->where('auditions.event_id', $eventId)
            ->groupBy('students.id')
            ->havingRaw('COUNT(entries.id) > 1')
            ->get();

        foreach ($studentsWithMultipleEntries as $student) {
            // Get entries that are not declined. If only one, they're our accepted entry.
            $availableEntries = $student->entries()->available()->get();
            if ($availableEntries->count() === 1) {
                $acceptedEntryId = $availableEntries->first()->id;
            } else {
                $acceptedEntryId = null;
            }
            // Create or update the doubler record
            static::updateOrCreate(
                [
                    'student_id' => $student->id,
                    'event_id' => $eventId,
                ],
                [
                    'accepted_entry' => $acceptedEntryId,
                ]
            );
        }

        // remove doubler records for students who no longer have multiple entries
        static::where('event_id', $eventId)
            ->whereNotIn('student_id', $studentsWithMultipleEntries->pluck('id'))
            ->delete();
    }

    public static function syncDoublers(): void
    {
        $events = Event::all();
        foreach ($events as $event) {
            static::syncForEvent($event);
        }
    }
}