<?php

namespace App\Models\Admin;

use App\Models\User;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Illuminate\Database\Eloquent\SoftDeletes;

/**
 * 프로젝트 관리 - 작업(Task) 모델
 *
 * @property int $id
 * @property int $project_id
 * @property string $title
 * @property string|null $description
 * @property string $status
 * @property string $priority
 * @property \Carbon\Carbon|null $due_date
 * @property int $sort_order
 * @property int|null $assignee_id
 * @property int|null $created_by
 * @property int|null $updated_by
 * @property int|null $deleted_by
 * @property \Carbon\Carbon $created_at
 * @property \Carbon\Carbon $updated_at
 * @property \Carbon\Carbon|null $deleted_at
 */
class AdminPmTask extends Model
{
    use SoftDeletes;

    protected $table = 'admin_pm_tasks';

    protected $fillable = [
        'project_id',
        'title',
        'description',
        'status',
        'priority',
        'is_urgent',
        'due_date',
        'sort_order',
        'assignee_id',
        'created_by',
        'updated_by',
        'deleted_by',
    ];

    protected $casts = [
        'project_id' => 'integer',
        'is_urgent' => 'boolean',
        'due_date' => 'date',
        'sort_order' => 'integer',
        'assignee_id' => 'integer',
        'created_by' => 'integer',
        'updated_by' => 'integer',
        'deleted_by' => 'integer',
    ];

    /**
     * 상태 상수
     */
    public const STATUS_TODO = 'todo';

    public const STATUS_IN_PROGRESS = 'in_progress';

    public const STATUS_DONE = 'done';

    /**
     * 우선순위 상수
     */
    public const PRIORITY_LOW = 'low';

    public const PRIORITY_MEDIUM = 'medium';

    public const PRIORITY_HIGH = 'high';

    /**
     * 상태 목록
     */
    public static function getStatuses(): array
    {
        return [
            self::STATUS_TODO => '예정',
            self::STATUS_IN_PROGRESS => '진행중',
            self::STATUS_DONE => '완료',
        ];
    }

    /**
     * 우선순위 목록
     */
    public static function getPriorities(): array
    {
        return [
            self::PRIORITY_LOW => '낮음',
            self::PRIORITY_MEDIUM => '보통',
            self::PRIORITY_HIGH => '높음',
        ];
    }

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

    /**
     * 우선순위별 필터
     */
    public function scopePriority($query, string $priority)
    {
        return $query->where('priority', $priority);
    }

    /**
     * 마감일 지난 작업
     */
    public function scopeOverdue($query)
    {
        return $query->whereNotNull('due_date')
            ->where('due_date', '<', now()->startOfDay())
            ->where('status', '!=', self::STATUS_DONE);
    }

    /**
     * 마감일 임박 (3일 이내)
     */
    public function scopeDueSoon($query, int $days = 3)
    {
        return $query->whereNotNull('due_date')
            ->whereBetween('due_date', [now()->startOfDay(), now()->addDays($days)->endOfDay()])
            ->where('status', '!=', self::STATUS_DONE);
    }

    /**
     * 관계: 프로젝트
     */
    public function project(): BelongsTo
    {
        return $this->belongsTo(AdminPmProject::class, 'project_id');
    }

    /**
     * 관계: 담당자
     */
    public function assignee(): BelongsTo
    {
        return $this->belongsTo(User::class, 'assignee_id');
    }

    /**
     * 관계: 연결된 이슈들
     */
    public function issues(): HasMany
    {
        return $this->hasMany(AdminPmIssue::class, 'task_id');
    }

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

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

    /**
     * D-day 계산 (마감일까지 남은 일수)
     */
    public function getDdayAttribute(): ?int
    {
        if (! $this->due_date) {
            return null;
        }

        return now()->startOfDay()->diffInDays($this->due_date, false);
    }

    /**
     * 마감 상태 (overdue, due_soon, normal, null)
     */
    public function getDueStatusAttribute(): ?string
    {
        if (! $this->due_date || $this->status === self::STATUS_DONE) {
            return null;
        }

        $dday = $this->dday;

        if ($dday < 0) {
            return 'overdue';
        }
        if ($dday <= 3) {
            return 'due_soon';
        }

        return 'normal';
    }
}