package nostr

import (
	"context"
	"fmt"

	"gitcitadel-online/internal/logger"

	"github.com/nbd-wtf/go-nostr"
)

// logFilter logs the exact filter being used for debugging
func logFilter(filter nostr.Filter, context string) {
	logger.WithFields(map[string]interface{}{
		"context": context,
		"kinds":   filter.Kinds,
		"authors": filter.Authors,
		"ids":     filter.IDs,
		"tags":    filter.Tags,
		"limit":   filter.Limit,
	}).Debug("Nostr filter")
}

// WikiService handles wiki-specific operations
type WikiService struct {
	client             *Client
	articleKinds       []int  // Allowed article kinds (from config)
	wikiKind           int    // Primary wiki kind constant (first from wiki_kinds config)
	blogKind           int    // Primary blog kind constant (first from blog_kinds config)
	additionalFallback string // Additional fallback relay URL (from config)
	indexKind          int    // Index event kind (from config)
}

// NewWikiService creates a new wiki service
func NewWikiService(client *Client, articleKinds []int, wikiKind int, additionalFallback string, indexKind int, blogKind int) *WikiService {
	return &WikiService{
		client:             client,
		articleKinds:       articleKinds,
		wikiKind:           wikiKind,
		blogKind:           blogKind,
		additionalFallback: additionalFallback,
		indexKind:          indexKind,
	}
}

// FetchWikiIndex fetches a wiki index by naddr
func (ws *WikiService) FetchWikiIndex(ctx context.Context, naddrStr string) (*IndexEvent, error) {
	// Parse naddr
	naddr, err := ParseNaddr(naddrStr)
	if err != nil {
		return nil, fmt.Errorf("failed to parse naddr: %w", err)
	}

	// Create filter for the index event
	filter := naddr.ToFilter()
	logFilter(filter, fmt.Sprintf("wiki index (kind %d)", ws.indexKind))

	// Fetch the event
	event, err := ws.client.FetchEvent(ctx, filter)
	if err != nil {
		return nil, fmt.Errorf("failed to fetch index event: %w", err)
	}

	// Parse the index event
	index, err := ParseIndexEvent(event, ws.indexKind)
	if err != nil {
		return nil, fmt.Errorf("failed to parse index event: %w", err)
	}

	return index, nil
}

// FetchWikiEvents fetches all wiki events referenced in an index
func (ws *WikiService) FetchWikiEvents(ctx context.Context, index *IndexEvent) ([]*WikiEvent, error) {
	var wikiEvents []*WikiEvent

	for _, item := range index.Items {
		if item.Kind != ws.wikiKind {
			continue // Skip non-wiki items
		}

		// Create filter for this wiki event
		filter := nostr.Filter{
			Kinds:   []int{ws.wikiKind},
			Authors: []string{item.Pubkey},
			Tags: map[string][]string{
				"d": {item.DTag},
			},
		}

		// If event ID is specified, use it for more reliable fetching
		if item.EventID != "" {
			filter.IDs = []string{item.EventID}
			logger.WithFields(map[string]interface{}{
				"event_id": item.EventID[:16] + "...",
				"dtag":     item.DTag,
			}).Debug("Using event ID for wiki event")
		}

		logFilter(filter, fmt.Sprintf("wiki event %s", item.DTag))

		// Use relay hint if available, otherwise use default client relays
		var event *nostr.Event
		var err error
		if item.RelayHint != "" {
			// Connect to the relay hint
			logger.WithFields(map[string]interface{}{
				"relay_hint": item.RelayHint,
				"dtag":       item.DTag,
			}).Debug("Trying relay hint")
			relay, relayErr := ws.client.ConnectToRelay(ctx, item.RelayHint)
			if relayErr == nil {
				events, queryErr := relay.QuerySync(ctx, filter)
				relay.Close()
				if queryErr == nil {
					if len(events) > 0 {
						event = events[0]
						logger.WithFields(map[string]interface{}{
							"dtag":       item.DTag,
							"relay_hint": item.RelayHint,
						}).Debug("Successfully fetched from relay hint")
					} else {
						logger.WithFields(map[string]interface{}{
							"relay_hint":   item.RelayHint,
							"dtag":         item.DTag,
							"has_event_id": item.EventID != "",
						}).Debug("Relay hint returned 0 events")
					}
				} else {
					logger.WithFields(map[string]interface{}{
						"relay_hint": item.RelayHint,
						"dtag":       item.DTag,
					}).Debugf("Error querying relay hint: %v", queryErr)
				}
			} else {
				logger.WithFields(map[string]interface{}{
					"relay_hint": item.RelayHint,
					"dtag":       item.DTag,
				}).Debugf("Error connecting to relay hint: %v", relayErr)
			}
		}

		// Fallback to default client relays if relay hint failed or wasn't provided
		// Client now queries all three relays automatically
		if event == nil {
			logger.WithField("dtag", item.DTag).Debug("Querying all relays")
			event, err = ws.client.FetchEvent(ctx, filter)
			if err != nil {
				// If still not found and event ID was specified, try without event ID to get latest replaceable event
				if item.EventID != "" {
					logger.WithField("dtag", item.DTag).Debug("Trying without event ID to get latest replaceable event")
					filterWithoutID := nostr.Filter{
						Kinds:   []int{ws.wikiKind},
						Authors: []string{item.Pubkey},
						Tags: map[string][]string{
							"d": {item.DTag},
						},
					}
					logFilter(filterWithoutID, fmt.Sprintf("wiki event %s (without event ID)", item.DTag))
					event, err = ws.client.FetchEvent(ctx, filterWithoutID)
					if err == nil {
						logger.WithField("dtag", item.DTag).Debug("Successfully fetched latest from all relays")
					}
				}
			} else {
				logger.WithField("dtag", item.DTag).Debug("Successfully fetched from all relays")
			}

			if event == nil {
				// Log error but continue with other events
				logger.WithFields(map[string]interface{}{
					"dtag":         item.DTag,
					"pubkey":       item.Pubkey,
					"has_event_id": item.EventID != "",
				}).Warnf("Error fetching wiki event: %v", err)
				continue
			}
		}

		// Parse the wiki event
		wiki, err := ParseWikiEvent(event, ws.wikiKind)
		if err != nil {
			logger.WithFields(map[string]interface{}{
				"dtag": item.DTag,
			}).Warnf("Error parsing wiki event: %v", err)
			continue
		}

		wikiEvents = append(wikiEvents, wiki)
	}

	if len(wikiEvents) == 0 && len(index.Items) > 0 {
		logger.WithField("items", len(index.Items)).Warn("No wiki events could be fetched from index items")
		// Return empty slice instead of error to allow landing page generation
	}

	return wikiEvents, nil
}

// GetBlogKind returns the blog kind configured in this service
func (ws *WikiService) GetBlogKind() int {
	return ws.blogKind
}

// FetchIndexEvents fetches all events of a specific kind referenced in an index
// Only supports article kinds configured in the service
func (ws *WikiService) FetchIndexEvents(ctx context.Context, index *IndexEvent, targetKind int) ([]*nostr.Event, error) {
	// Check if the target kind is in the allowed article kinds
	allowed := false
	for _, kind := range ws.articleKinds {
		if kind == targetKind {
			allowed = true
			break
		}
	}
	if !allowed {
		return nil, fmt.Errorf("unsupported event kind: %d (only %v are supported)", targetKind, ws.articleKinds)
	}

	var events []*nostr.Event

	for _, item := range index.Items {
		// Only process items of the target kind
		if item.Kind != targetKind {
			continue // Skip items that don't match the target kind
		}

		// Create filter for this event
		filter := nostr.Filter{
			Kinds:   []int{targetKind},
			Authors: []string{item.Pubkey},
			Tags: map[string][]string{
				"d": {item.DTag},
			},
		}

		// If event ID is specified, use it for more reliable fetching
		if item.EventID != "" {
			filter.IDs = []string{item.EventID}
		}

		logFilter(filter, fmt.Sprintf("index event kind %d %s", targetKind, item.DTag))

		// Use relay hint if available, otherwise use default client relays
		var event *nostr.Event
		var err error
		if item.RelayHint != "" {
			// Connect to the relay hint
			relay, relayErr := ws.client.ConnectToRelay(ctx, item.RelayHint)
			if relayErr == nil {
				relayEvents, queryErr := relay.QuerySync(ctx, filter)
				relay.Close()
				if queryErr == nil {
					if len(relayEvents) > 0 {
						event = relayEvents[0]
					} else {
						logger.WithFields(map[string]interface{}{
							"relay_hint":   item.RelayHint,
							"dtag":         item.DTag,
							"kind":         targetKind,
							"has_event_id": item.EventID != "",
						}).Debug("Relay hint returned 0 events")
					}
				} else {
					logger.WithFields(map[string]interface{}{
						"relay_hint": item.RelayHint,
						"dtag":       item.DTag,
						"kind":       targetKind,
					}).Debugf("Error querying relay hint: %v", queryErr)
				}
			} else {
				logger.WithFields(map[string]interface{}{
					"relay_hint": item.RelayHint,
					"dtag":       item.DTag,
					"kind":       targetKind,
				}).Debugf("Error connecting to relay hint: %v", relayErr)
			}
		}

		// Fallback to default client relays if relay hint failed or wasn't provided
		// Client now queries all three relays automatically
		if event == nil {
			logger.WithFields(map[string]interface{}{
				"dtag": item.DTag,
				"kind": targetKind,
			}).Debug("Querying all relays")
			event, err = ws.client.FetchEvent(ctx, filter)
			if err != nil {
				// If still not found and event ID was specified, try without event ID to get latest replaceable event
				if item.EventID != "" {
					logger.WithFields(map[string]interface{}{
						"dtag": item.DTag,
						"kind": targetKind,
					}).Debug("Trying without event ID to get latest replaceable event")
					filterWithoutID := nostr.Filter{
						Kinds:   []int{targetKind},
						Authors: []string{item.Pubkey},
						Tags: map[string][]string{
							"d": {item.DTag},
						},
					}
					logFilter(filterWithoutID, fmt.Sprintf("index event kind %d %s (without event ID)", targetKind, item.DTag))
					event, err = ws.client.FetchEvent(ctx, filterWithoutID)
					if err == nil {
						logger.WithFields(map[string]interface{}{
							"dtag": item.DTag,
							"kind": targetKind,
						}).Debug("Successfully fetched latest from all relays")
					}
				}
			} else {
				logger.WithFields(map[string]interface{}{
					"dtag": item.DTag,
					"kind": targetKind,
				}).Debug("Successfully fetched from all relays")
			}

			if event == nil {
				// Log error but continue with other events
				logger.WithFields(map[string]interface{}{
					"dtag":         item.DTag,
					"kind":         targetKind,
					"pubkey":       item.Pubkey,
					"has_event_id": item.EventID != "",
				}).Warnf("Error fetching event: %v", err)
				continue
			}
		}

		events = append(events, event)
	}

	if len(events) == 0 && len(index.Items) > 0 {
		logger.WithFields(map[string]interface{}{
			"kind":  targetKind,
			"items": len(index.Items),
		}).Warn("No events could be fetched from index items")
	}

	return events, nil
}

// FetchWikiEventByDTag fetches a single wiki event by d tag
func (ws *WikiService) FetchWikiEventByDTag(ctx context.Context, pubkey, dTag string) (*WikiEvent, error) {
	filter := nostr.Filter{
		Kinds:   []int{ws.wikiKind},
		Authors: []string{pubkey},
		Tags: map[string][]string{
			"d": {dTag},
		},
		Limit: 1,
	}
	logFilter(filter, fmt.Sprintf("wiki by d-tag %s", dTag))

	event, err := ws.client.FetchEvent(ctx, filter)
	if err != nil {
		return nil, fmt.Errorf("failed to fetch wiki event: %w", err)
	}

	return ParseWikiEvent(event, ws.wikiKind)
}