<?php

namespace App\Models;

use App\User;
use Carbon\Carbon;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Database\Eloquent\Collection;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Illuminate\Database\Eloquent\SoftDeletes;

/**
 * Angebot (Modul 6).
 *
 * Ein Offer ist der logische Angebots-Kopf (Angebotsnummer, Status,
 * Referenzen). Die Inhalte (Texte, Positionen, PDF) liegen versionsweise
 * in {@see OfferVersion}. Nach dem ersten Versand ist jede Änderung
 * eine neue Version (Entscheidung 17.1 Entwicklungsplan).
 *
 * @property int $id
 * @property string $offer_number
 * @property int $contact_id
 * @property int|null $inquiry_id
 * @property int|null $booking_id
 * @property string $status
 * @property int|null $current_version_id
 * @property int $created_by
 * @property Carbon $created_at
 * @property Carbon $updated_at
 * @property Carbon|null $deleted_at
 * @property-read Contact $contact
 * @property-read Lead|null $inquiry
 * @property-read Booking|null $booking
 * @property-read OfferVersion|null $currentVersion
 * @property-read Collection|OfferVersion[] $versions
 * @property-read Collection|OfferAccessToken[] $accessTokens
 * @property-read User $creator
 */
class Offer extends Model
{
    use HasFactory, SoftDeletes;

    public const STATUS_DRAFT     = 'draft';
    public const STATUS_SENT      = 'sent';
    public const STATUS_ACCEPTED  = 'accepted';
    public const STATUS_DECLINED  = 'declined';
    public const STATUS_EXPIRED   = 'expired';
    public const STATUS_WITHDRAWN = 'withdrawn';

    public const STATUSES = [
        self::STATUS_DRAFT,
        self::STATUS_SENT,
        self::STATUS_ACCEPTED,
        self::STATUS_DECLINED,
        self::STATUS_EXPIRED,
        self::STATUS_WITHDRAWN,
    ];

    protected $table = 'offers';

    protected $fillable = [
        'offer_number',
        'contact_id',
        'inquiry_id',
        'booking_id',
        'status',
        'current_version_id',
        'created_by',
    ];

    protected $casts = [
        'contact_id'         => 'int',
        'inquiry_id'         => 'int',
        'booking_id'         => 'int',
        'current_version_id' => 'int',
        'created_by'         => 'int',
    ];

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

    public function inquiry(): BelongsTo
    {
        // Nach Modul 3 Phase 2: `Lead`-Model bildet die `inquiries`-Tabelle ab
        return $this->belongsTo(Lead::class, 'inquiry_id');
    }

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

    public function currentVersion(): BelongsTo
    {
        return $this->belongsTo(OfferVersion::class, 'current_version_id');
    }

    public function versions(): HasMany
    {
        return $this->hasMany(OfferVersion::class)->orderBy('version_no');
    }

    public function accessTokens(): HasMany
    {
        return $this->hasMany(OfferAccessToken::class);
    }

    public function creator(): BelongsTo
    {
        return $this->belongsTo(User::class, 'created_by');
    }

    public function scopeStatus(Builder $q, string $status): Builder
    {
        return $q->where('status', $status);
    }

    public function scopeOpen(Builder $q): Builder
    {
        return $q->whereIn('status', [self::STATUS_DRAFT, self::STATUS_SENT]);
    }

    public function isEditable(): bool
    {
        return in_array($this->status, [self::STATUS_DRAFT, self::STATUS_SENT], true);
    }
}