package monitoring

import (
	"strings"

	"github.com/rcourtman/pulse-go-rewrite/internal/alerts"
	"github.com/rcourtman/pulse-go-rewrite/internal/logging"
	"github.com/rcourtman/pulse-go-rewrite/internal/models"
	"github.com/rcourtman/pulse-go-rewrite/internal/unifiedresources"
	"github.com/rs/zerolog"
	"github.com/rs/zerolog/log"
)

// syncAlertsToState copies the latest alert manager data into the shared state snapshot.
// This keeps WebSocket broadcasts aligned with in-memory acknowledgement updates.
func (m *Monitor) syncAlertsToState() {
	if m.pruneStaleDockerAlerts() {
		if logging.IsLevelEnabled(zerolog.DebugLevel) {
			log.Debug().Msg("pruned stale docker alerts during sync")
		}
	}

	modelAlerts := m.activeAlertsSnapshot()
	for _, alert := range modelAlerts {
		if alert.Acknowledged && logging.IsLevelEnabled(zerolog.DebugLevel) {
			log.Debug().Str("alertID", alert.ID).Interface("ackTime", alert.AckTime).Msg("syncing acknowledged alert")
		}
	}
	m.state.UpdateActiveAlerts(modelAlerts)

	recentlyResolved := m.alertManager.GetRecentlyResolved()
	if len(recentlyResolved) > 0 && logging.IsLevelEnabled(zerolog.DebugLevel) {
		log.Debug().Int("count", len(recentlyResolved)).Msg("syncing recently resolved alerts")
	}
	m.state.UpdateRecentlyResolved(recentlyResolved)
}

// SyncAlertState is the exported wrapper used by APIs that mutate alerts outside the poll loop.
func (m *Monitor) SyncAlertState() {
	m.syncAlertsToState()
}

func (m *Monitor) activeAlertsSnapshot() []models.Alert {
	if m == nil {
		return nil
	}
	if m.alertManager == nil {
		if m.state == nil {
			return nil
		}
		return m.state.GetSnapshot().ActiveAlerts
	}

	activeAlerts := m.alertManager.GetActiveAlerts()
	modelAlerts := make([]models.Alert, 0, len(activeAlerts))
	for _, alert := range activeAlerts {
		modelAlerts = append(modelAlerts, models.Alert{
			ID:              alert.ID,
			Type:            alert.Type,
			Level:           string(alert.Level),
			ResourceID:      alert.ResourceID,
			ResourceName:    alert.ResourceName,
			Node:            alert.Node,
			NodeDisplayName: alert.NodeDisplayName,
			Instance:        alert.Instance,
			Message:         alert.Message,
			Value:           alert.Value,
			Threshold:       alert.Threshold,
			StartTime:       alert.StartTime,
			Acknowledged:    alert.Acknowledged,
			AckTime:         alert.AckTime,
			AckUser:         alert.AckUser,
			// GetActiveAlerts returns deep clones, so the map is already private.
			Metadata: alert.Metadata,
		})
	}
	return modelAlerts
}

func (m *Monitor) recentlyResolvedAlertsSnapshot() []models.ResolvedAlert {
	if m == nil {
		return nil
	}
	if m.alertManager == nil {
		if m.state == nil {
			return nil
		}
		return m.state.GetSnapshot().RecentlyResolved
	}

	return m.alertManager.GetRecentlyResolved()
}

func (m *Monitor) syncUnifiedResourceAlertsToState(resources []unifiedresources.Resource) {
	if m == nil || m.alertManager == nil {
		return
	}

	config := m.alertManager.GetConfig()
	migrated := alerts.MigrateCanonicalOverrideKeys(&config, resources)
	if alerts.MigrateDockerContainerOverrideKeys(&config, resources) {
		migrated = true
	}
	if migrated {
		if m.configPersist == nil {
			log.Warn().Msg("cannot persist canonical alert override migration without config persistence")
		} else if err := m.configPersist.SaveAlertConfig(config); err != nil {
			log.Error().Err(err).Msg("failed to persist canonical alert override migration")
		} else {
			m.alertManager.UpdateConfig(config)
		}
	}

	m.migrateAvailabilityLinksToCanonicalIDs(resources)

	m.alertManager.CheckUnifiedResourceMetrics(resources)
	m.alertManager.SyncUnifiedResourceIncidents(resources)
	m.syncAlertsToState()
}

// pruneStaleDockerAlerts removes docker alerts that reference hosts no longer present in state.
func (m *Monitor) pruneStaleDockerAlerts() bool {
	if m.alertManager == nil {
		return false
	}

	readState := m.GetUnifiedReadStateOrSnapshot()
	if readState == nil {
		return false
	}

	hosts := readState.DockerHosts()
	knownHosts := make(map[string]struct{}, len(hosts)*2)
	for _, host := range hosts {
		hostID := strings.TrimSpace(host.ID())
		if hostID != "" {
			knownHosts[hostID] = struct{}{}
		}
		if sourceID := strings.TrimSpace(host.HostSourceID()); sourceID != "" {
			knownHosts[sourceID] = struct{}{}
		}
	}

	if len(knownHosts) == 0 {
		// Still allow stale entries to be cleared if no hosts remain.
	}

	active := m.alertManager.GetActiveAlerts()
	processed := make(map[string]struct{})
	cleared := false

	for _, alert := range active {
		var hostID string

		switch {
		case alert.Type == "docker-host-offline":
			hostID = strings.TrimPrefix(strings.TrimSpace(alert.ResourceID), "docker:")
		case strings.HasPrefix(alert.ResourceID, "docker:"):
			resource := strings.TrimPrefix(alert.ResourceID, "docker:")
			if idx := strings.Index(resource, "/"); idx >= 0 {
				hostID = resource[:idx]
			} else {
				hostID = resource
			}
		default:
			continue
		}

		hostID = strings.TrimSpace(hostID)
		if hostID == "" {
			continue
		}

		if _, known := knownHosts[hostID]; known {
			continue
		}
		if _, alreadyCleared := processed[hostID]; alreadyCleared {
			continue
		}

		host := models.DockerHost{
			ID:          hostID,
			DisplayName: alert.ResourceName,
			Hostname:    alert.Node,
		}
		if host.DisplayName == "" {
			host.DisplayName = hostID
		}
		if host.Hostname == "" {
			host.Hostname = hostID
		}

		m.alertManager.HandleDockerHostRemoved(host)
		processed[hostID] = struct{}{}
		cleared = true
	}

	return cleared
}