<?php

namespace App\Models\Documents;

use App\Models\DocumentTemplate;
use App\Models\User;
use App\Traits\BelongsToTenant;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Illuminate\Database\Eloquent\Relations\MorphTo;
use Illuminate\Database\Eloquent\SoftDeletes;

class Document extends Model
{
    use BelongsToTenant, SoftDeletes;

    protected $table = 'documents';

    // 상태 상수
    public const STATUS_DRAFT = 'DRAFT';

    public const STATUS_PENDING = 'PENDING';

    public const STATUS_APPROVED = 'APPROVED';

    public const STATUS_REJECTED = 'REJECTED';

    public const STATUS_CANCELLED = 'CANCELLED';

    public const STATUSES = [
        self::STATUS_DRAFT,
        self::STATUS_PENDING,
        self::STATUS_APPROVED,
        self::STATUS_REJECTED,
        self::STATUS_CANCELLED,
    ];

    public const STATUS_LABELS = [
        self::STATUS_DRAFT => '작성중',
        self::STATUS_PENDING => '결재중',
        self::STATUS_APPROVED => '승인',
        self::STATUS_REJECTED => '반려',
        self::STATUS_CANCELLED => '취소',
    ];

    protected $fillable = [
        'tenant_id',
        'template_id',
        'document_no',
        'title',
        'status',
        'linkable_type',
        'linkable_id',
        'submitted_at',
        'completed_at',
        'created_by',
        'updated_by',
        'deleted_by',
    ];

    protected $casts = [
        'submitted_at' => 'datetime',
        'completed_at' => 'datetime',
    ];

    protected $attributes = [
        'status' => self::STATUS_DRAFT,
    ];

    // =========================================================================
    // Relationships
    // =========================================================================

    public function template(): BelongsTo
    {
        return $this->belongsTo(DocumentTemplate::class, 'template_id');
    }

    public function approvals(): HasMany
    {
        return $this->hasMany(DocumentApproval::class)->orderBy('step');
    }

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

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

    public function linkable(): MorphTo
    {
        return $this->morphTo();
    }

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

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

    // =========================================================================
    // Accessors
    // =========================================================================

    public function getStatusLabelAttribute(): string
    {
        return self::STATUS_LABELS[$this->status] ?? $this->status;
    }

    public function getStatusColorAttribute(): string
    {
        return match ($this->status) {
            self::STATUS_DRAFT => 'gray',
            self::STATUS_PENDING => 'yellow',
            self::STATUS_APPROVED => 'green',
            self::STATUS_REJECTED => 'red',
            self::STATUS_CANCELLED => 'gray',
            default => 'gray',
        };
    }

    // =========================================================================
    // Scopes
    // =========================================================================

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

    public function scopeDraft($query)
    {
        return $query->where('status', self::STATUS_DRAFT);
    }

    public function scopePending($query)
    {
        return $query->where('status', self::STATUS_PENDING);
    }

    // =========================================================================
    // Helper Methods
    // =========================================================================

    public function isDraft(): bool
    {
        return $this->status === self::STATUS_DRAFT;
    }

    public function isPending(): bool
    {
        return $this->status === self::STATUS_PENDING;
    }

    public function isApproved(): bool
    {
        return $this->status === self::STATUS_APPROVED;
    }

    public function isRejected(): bool
    {
        return $this->status === self::STATUS_REJECTED;
    }

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