package entities

import (
	"time"

	"github.com/google/uuid"
	"gorm.io/gorm"
)

// TaskStatus 任务状态
type TaskStatus string

const (
	TaskStatusPending   TaskStatus = "pending"
	TaskStatusRunning   TaskStatus = "running"
	TaskStatusCompleted TaskStatus = "completed"
	TaskStatusFailed    TaskStatus = "failed"
	TaskStatusCancelled TaskStatus = "cancelled"
)

// AsyncTask 异步任务实体
type AsyncTask struct {
	ID          string     `gorm:"type:char(36);primaryKey"`
	Type        string     `gorm:"not null;index"`
	Payload     string     `gorm:"type:text"`
	Status      TaskStatus `gorm:"not null;index"`
	ScheduledAt *time.Time `gorm:"index"`
	StartedAt   *time.Time
	CompletedAt *time.Time
	ErrorMsg    string
	RetryCount  int `gorm:"default:0"`
	MaxRetries  int `gorm:"default:5"`
	CreatedAt   time.Time
	UpdatedAt   time.Time
}

// TableName 指定表名
func (AsyncTask) TableName() string {
	return "async_tasks"
}

// BeforeCreate GORM钩子，在创建前生成UUID
func (t *AsyncTask) BeforeCreate(tx *gorm.DB) error {
	if t.ID == "" {
		t.ID = uuid.New().String()
	}
	return nil
}

// IsCompleted 检查任务是否已完成
func (t *AsyncTask) IsCompleted() bool {
	return t.Status == TaskStatusCompleted
}

// IsFailed 检查任务是否失败
func (t *AsyncTask) IsFailed() bool {
	return t.Status == TaskStatusFailed
}

// IsCancelled 检查任务是否已取消
func (t *AsyncTask) IsCancelled() bool {
	return t.Status == TaskStatusCancelled
}

// CanRetry 检查任务是否可以重试
func (t *AsyncTask) CanRetry() bool {
	return t.Status == TaskStatusFailed && t.RetryCount < t.MaxRetries
}