// purgeArchivedMetric deletes an archived fingerprint and its corresponding
// metric entirely. It also queues the metric for un-indexing (no need to call
// unindexMetric for the deleted metric.) It does not touch the series file,
// though. The caller must have locked the fingerprint.
func (p *persistence) purgeArchivedMetric(fp clientmodel.Fingerprint) (err error) {
	defer func() {
		if err != nil {
			p.setDirty(true)
		}
	}()

	metric, err := p.archivedMetric(fp)
	if err != nil || metric == nil {
		return err
	}
	deleted, err := p.archivedFingerprintToMetrics.Delete(codable.Fingerprint(fp))
	if err != nil {
		return err
	}
	if !deleted {
		log.Errorf("Tried to delete non-archived fingerprint %s from archivedFingerprintToMetrics index. This should never happen.", fp)
	}
	deleted, err = p.archivedFingerprintToTimeRange.Delete(codable.Fingerprint(fp))
	if err != nil {
		return err
	}
	if !deleted {
		log.Errorf("Tried to delete non-archived fingerprint %s from archivedFingerprintToTimeRange index. This should never happen.", fp)
	}
	p.unindexMetric(fp, metric)
	return nil
}

// unarchiveMetric deletes an archived fingerprint and its metric, but (in
// contrast to purgeArchivedMetric) does not un-index the metric.  If a metric
// was actually deleted, the method returns true and the first time of the
// deleted metric. The caller must have locked the fingerprint.
func (p *persistence) unarchiveMetric(fp clientmodel.Fingerprint) (
	deletedAnything bool,
	firstDeletedTime clientmodel.Timestamp,
	err error,
) {
	defer func() {
		if err != nil {
			p.setDirty(true)
		}
	}()

	firstTime, _, has, err := p.archivedFingerprintToTimeRange.Lookup(fp)
	if err != nil || !has {
		return false, firstTime, err
	}
	deleted, err := p.archivedFingerprintToMetrics.Delete(codable.Fingerprint(fp))
	if err != nil {
		return false, firstTime, err
	}
	if !deleted {
		log.Errorf("Tried to delete non-archived fingerprint %s from archivedFingerprintToMetrics index. This should never happen.", fp)
	}
	deleted, err = p.archivedFingerprintToTimeRange.Delete(codable.Fingerprint(fp))
	if err != nil {
		return false, firstTime, err
	}
	if !deleted {
		log.Errorf("Tried to delete non-archived fingerprint %s from archivedFingerprintToTimeRange index. This should never happen.", fp)
	}
	return true, firstTime, nil
}

// archiveMetric persists the mapping of the given fingerprint to the given
// metric, together with the first and last timestamp of the series belonging to
// the metric. The caller must have locked the fingerprint.
func (p *persistence) archiveMetric(
	fp model.Fingerprint, m model.Metric, first, last model.Time,
) {
	if err := p.archivedFingerprintToMetrics.Put(codable.Fingerprint(fp), codable.Metric(m)); err != nil {
		p.setDirty(fmt.Errorf("error in method archiveMetric inserting fingerprint %v into FingerprintToMetrics: %s", fp, err))
		return
	}
	if err := p.archivedFingerprintToTimeRange.Put(codable.Fingerprint(fp), codable.TimeRange{First: first, Last: last}); err != nil {
		p.setDirty(fmt.Errorf("error in method archiveMetric inserting fingerprint %v into FingerprintToTimeRange: %s", fp, err))
	}
}

// archiveMetric persists the mapping of the given fingerprint to the given
// metric, together with the first and last timestamp of the series belonging to
// the metric. The caller must have locked the fingerprint.
func (p *persistence) archiveMetric(
	fp clientmodel.Fingerprint, m clientmodel.Metric, first, last clientmodel.Timestamp,
) error {
	if err := p.archivedFingerprintToMetrics.Put(codable.Fingerprint(fp), codable.Metric(m)); err != nil {
		p.setDirty(true)
		return err
	}
	if err := p.archivedFingerprintToTimeRange.Put(codable.Fingerprint(fp), codable.TimeRange{First: first, Last: last}); err != nil {
		p.setDirty(true)
		return err
	}
	return nil
}

// unarchiveMetric deletes an archived fingerprint and its metric, but (in
// contrast to purgeArchivedMetric) does not un-index the metric.  If a metric
// was actually deleted, the method returns true and the first time and last
// time of the deleted metric. The caller must have locked the fingerprint.
func (p *persistence) unarchiveMetric(fp model.Fingerprint) (deletedAnything bool, err error) {
	// An error returned here will bubble up and lead to quarantining of the
	// series, so no setDirty required.
	deleted, err := p.archivedFingerprintToMetrics.Delete(codable.Fingerprint(fp))
	if err != nil || !deleted {
		return false, err
	}
	deleted, err = p.archivedFingerprintToTimeRange.Delete(codable.Fingerprint(fp))
	if err != nil {
		return false, err
	}
	if !deleted {
		log.Errorf("Tried to delete non-archived fingerprint %s from archivedFingerprintToTimeRange index. This should never happen.", fp)
	}
	return true, nil
}

// UnindexBatch unindexes a batch of mappings from fingerprints to metrics.
//
// This method is goroutine-safe, but note that no specific order of execution
// can be guaranteed (especially critical if IndexBatch and UnindexBatch are
// called concurrently for the same fingerprint).
func (i *FingerprintMetricIndex) UnindexBatch(mapping FingerprintMetricMapping) error {
	b := i.NewBatch()

	for fp := range mapping {
		b.Delete(codable.Fingerprint(fp))
	}

	return i.Commit(b)
}

// IndexBatch indexes a batch of mappings from fingerprints to metrics.
//
// This method is goroutine-safe, but note that no specific order of execution
// can be guaranteed (especially critical if IndexBatch and UnindexBatch are
// called concurrently for the same fingerprint).
func (i *FingerprintMetricIndex) IndexBatch(mapping FingerprintMetricMapping) error {
	b := i.NewBatch()

	for fp, m := range mapping {
		b.Put(codable.Fingerprint(fp), codable.Metric(m))
	}

	return i.Commit(b)
}

// unarchiveMetric deletes an archived fingerprint and its metric, but (in
// contrast to purgeArchivedMetric) does not un-index the metric.  If a metric
// was actually deleted, the method returns true and the first time and last
// time of the deleted metric. The caller must have locked the fingerprint.
func (p *persistence) unarchiveMetric(fp model.Fingerprint) (deletedAnything bool, err error) {
	defer func() {
		if err != nil {
			p.setDirty(true)
		}
	}()

	deleted, err := p.archivedFingerprintToMetrics.Delete(codable.Fingerprint(fp))
	if err != nil || !deleted {
		return false, err
	}
	deleted, err = p.archivedFingerprintToTimeRange.Delete(codable.Fingerprint(fp))
	if err != nil {
		return false, err
	}
	if !deleted {
		log.Errorf("Tried to delete non-archived fingerprint %s from archivedFingerprintToTimeRange index. This should never happen.", fp)
	}
	return true, nil
}

// dropArchivedMetric deletes an archived fingerprint and its corresponding
// metric entirely. It also queues the metric for un-indexing (no need to call
// unindexMetric for the deleted metric.)  The caller must have locked the
// fingerprint.
func (p *persistence) dropArchivedMetric(fp clientmodel.Fingerprint) (err error) {
	defer func() {
		if err != nil {
			p.setDirty(true)
		}
	}()

	metric, err := p.getArchivedMetric(fp)
	if err != nil || metric == nil {
		return err
	}
	if err := p.archivedFingerprintToMetrics.Delete(codable.Fingerprint(fp)); err != nil {
		return err
	}
	if err := p.archivedFingerprintToTimeRange.Delete(codable.Fingerprint(fp)); err != nil {
		return err
	}
	p.unindexMetric(fp, metric)
	return nil
}

// unarchiveMetric deletes an archived fingerprint and its metric, but (in
// contrast to dropArchivedMetric) does not un-index the metric.  If a metric
// was actually deleted, the method returns true and the first time of the
// deleted metric. The caller must have locked the fingerprint.
func (p *persistence) unarchiveMetric(fp clientmodel.Fingerprint) (
	deletedAnything bool,
	firstDeletedTime clientmodel.Timestamp,
	err error,
) {
	defer func() {
		if err != nil {
			p.setDirty(true)
		}
	}()

	firstTime, _, has, err := p.archivedFingerprintToTimeRange.Lookup(fp)
	if err != nil || !has {
		return false, firstTime, err
	}
	if err := p.archivedFingerprintToMetrics.Delete(codable.Fingerprint(fp)); err != nil {
		return false, firstTime, err
	}
	if err := p.archivedFingerprintToTimeRange.Delete(codable.Fingerprint(fp)); err != nil {
		return false, firstTime, err
	}
	return true, firstTime, nil
}

// Lookup looks up a metric by fingerprint. Looking up a non-existing
// fingerprint is not an error. In that case, (nil, false, nil) is returned.
//
// This method is goroutine-safe.
func (i *FingerprintMetricIndex) Lookup(fp model.Fingerprint) (metric model.Metric, ok bool, err error) {
	ok, err = i.Get(codable.Fingerprint(fp), (*codable.Metric)(&metric))
	return
}

// updateArchivedTimeRange updates an archived time range. The caller must make
// sure that the fingerprint is currently archived (the time range will
// otherwise be added without the corresponding metric in the archive).
func (p *persistence) updateArchivedTimeRange(
	fp clientmodel.Fingerprint, first, last clientmodel.Timestamp,
) error {
	return p.archivedFingerprintToTimeRange.Put(codable.Fingerprint(fp), codable.TimeRange{First: first, Last: last})
}