package useCases

import (
	"RenewCMS/internal/domain/audit"
	"RenewCMS/internal/domain/purge"
	"context"
	"errors"
	"time"
)

type PurgeRunner interface {
	Execute(fingerprint *string) (purge.RunResult, error)
}

type PurgeSchedulerUseCase struct {
	repository purge.Repository
	runner     PurgeRunner
	recorder   audit.Recorder
}

func NewPurgeSchedulerUseCase(repository purge.Repository, runner PurgeRunner, recorder audit.Recorder) *PurgeSchedulerUseCase {
	return &PurgeSchedulerUseCase{repository, runner, recorder}
}

func (u *PurgeSchedulerUseCase) Tick(now time.Time) (purge.RunResult, bool, error) {
	settings, err := u.repository.Get()
	if err != nil {
		return purge.RunResult{}, false, err
	}
	next := settings.NextPurgeAt()
	if next == nil || now.Before(*next) {
		return purge.RunResult{}, false, nil
	}
	result, err := u.runner.Execute(nil)
	if err != nil {
		u.recordFailedRun(err)
		return purge.RunResult{}, false, err
	}
	if result.GroupsTotal > 0 {
		event := systemPurgeEvent()
		event.Params = purgeParams(result)
		u.recorder.Record(context.Background(), event)
	}
	return result, true, nil
}

func (u *PurgeSchedulerUseCase) recordFailedRun(err error) {
	if errors.Is(err, purge.ErrPurgeBusy) {
		return
	}
	failFrom(context.Background(), u.recorder, systemPurgeEvent(), reasonFor(err))
}

func systemPurgeEvent() audit.Event {
	event := audit.NewEvent(audit.ActionMediaPurgeScheduled, audit.CategorySystem)
	event.Actor = audit.SystemActor()
	event.Source = audit.SourceSystem
	return event
}