package model

import (
	"encoding/json"
	"time"
)

const (
	BackgroundJobStatusQueued    = "queued"
	BackgroundJobStatusRunning   = "running"
	BackgroundJobStatusRetrying  = "retrying"
	BackgroundJobStatusCompleted = "completed"
	BackgroundJobStatusDead      = "dead"
)

const DefaultBackgroundJobQueue = "default"

// BackgroundJob stores durable background work in the database.
// Reference: Chatwoot ActiveJob/Sidekiq jobs with retry, delayed scheduling,
// mutex/idempotency, and observable failure state.
type BackgroundJob struct {
	ID             uint            `gorm:"primaryKey" json:"id"`
	Queue          string          `gorm:"size:100;not null;default:'default';index:idx_background_jobs_ready,priority:2" json:"queue"`
	JobType        string          `gorm:"size:150;not null;index" json:"job_type"`
	Payload        json.RawMessage `gorm:"type:jsonb;not null;default:'{}'" json:"payload"`
	Status         string          `gorm:"size:50;not null;default:'queued';index:idx_background_jobs_ready,priority:1" json:"status"`
	Priority       int             `gorm:"not null;default:0" json:"priority"`
	Attempts       int             `gorm:"not null;default:0" json:"attempts"`
	MaxAttempts    int             `gorm:"not null;default:3" json:"max_attempts"`
	ScheduledAt    time.Time       `gorm:"not null;index:idx_background_jobs_ready,priority:3" json:"scheduled_at"`
	LockedAt       *time.Time      `gorm:"index" json:"locked_at,omitempty"`
	LockedBy       string          `gorm:"size:150" json:"locked_by,omitempty"`
	IdempotencyKey string          `gorm:"size:255;index" json:"idempotency_key,omitempty"`
	LastError      string          `gorm:"type:text" json:"last_error,omitempty"`
	FinishedAt     *time.Time      `json:"finished_at,omitempty"`
	FailedAt       *time.Time      `json:"failed_at,omitempty"`
	CreatedAt      time.Time       `gorm:"autoCreateTime" json:"created_at"`
	UpdatedAt      time.Time       `gorm:"autoUpdateTime" json:"updated_at"`
}

func (BackgroundJob) TableName() string { return "background_jobs" }