package repository

import (
	"bugulma/backend/internal/domain"
	"context"
	"fmt"
	"time"

	"github.com/neo4j/neo4j-go-driver/v5/neo4j"
)

// GraphAddressRepository manages Address nodes in Neo4j
type GraphAddressRepository struct {
	driver   neo4j.DriverWithContext
	database string
}

// NewGraphAddressRepository creates a new graph address repository
func NewGraphAddressRepository(driver neo4j.DriverWithContext, dbName string) *GraphAddressRepository {
	return &GraphAddressRepository{
		driver:   driver,
		database: dbName,
	}
}

// SyncToGraph syncs an address to the graph database
func (r *GraphAddressRepository) SyncToGraph(ctx context.Context, address *domain.Address) error {
	session := r.driver.NewSession(ctx, neo4j.SessionConfig{
		AccessMode:   neo4j.AccessModeWrite,
		DatabaseName: r.database,
	})
	defer session.Close(ctx)

	// Use ExecuteWrite for automatic retry logic
	_, err := session.ExecuteWrite(ctx, func(tx neo4j.ManagedTransaction) (interface{}, error) {
		cypher := `
			MERGE (a:Address {id: $id})
			SET a.street = $street,
				a.city = $city,
				a.region = $region,
				a.postal_code = $postal_code,
				a.country = $country,
				a.formatted_ru = $formatted_ru,
				a.formatted_en = $formatted_en,
				a.formatted_tt = $formatted_tt,
				a.latitude = $latitude,
				a.longitude = $longitude,
				a.address_type = $address_type,
				a.verified = $verified,
				a.source = $source,
				a.created_at = $created_at,
				a.updated_at = $updated_at
			RETURN a.id
		`

		params := map[string]interface{}{
			"id":           address.ID,
			"street":       address.Street,
			"city":         address.City,
			"region":       address.Region,
			"postal_code":  address.PostalCode,
			"country":      address.Country,
			"formatted_ru": address.FormattedRu,
			"formatted_en": address.FormattedEn,
			"formatted_tt": address.FormattedTt,
			"latitude":     address.Latitude,
			"longitude":    address.Longitude,
			"address_type": string(address.AddressType),
			"verified":     address.Verified,
			"source":       address.Source,
			"created_at":   address.CreatedAt.Format(time.RFC3339),
			"updated_at":   address.UpdatedAt.Format(time.RFC3339),
		}

		result, err := tx.Run(ctx, cypher, params)
		if err != nil {
			return nil, fmt.Errorf("failed to execute address merge: %w", err)
		}

		if err := result.Err(); err != nil {
			return nil, fmt.Errorf("failed to consume address result: %w", err)
		}

		return nil, nil
	})

	return err
}

// SyncWithRelationships syncs an address and creates LOCATED_AT relationships
// This is the recommended method for bulk sync as it handles both node and relationships atomically
func (r *GraphAddressRepository) SyncWithRelationships(ctx context.Context, address *domain.Address, orgIDs []string, siteIDs []string) error {
	session := r.driver.NewSession(ctx, neo4j.SessionConfig{
		AccessMode:   neo4j.AccessModeWrite,
		DatabaseName: r.database,
	})
	defer session.Close(ctx)

	// Use ExecuteWrite with a single transaction for atomicity
	_, err := session.ExecuteWrite(ctx, func(tx neo4j.ManagedTransaction) (interface{}, error) {
		// First, create/update the Address node
		addressCypher := `
			MERGE (a:Address {id: $id})
			SET a.street = $street,
				a.city = $city,
				a.region = $region,
				a.postal_code = $postal_code,
				a.country = $country,
				a.formatted_ru = $formatted_ru,
				a.formatted_en = $formatted_en,
				a.formatted_tt = $formatted_tt,
				a.latitude = $latitude,
				a.longitude = $longitude,
				a.address_type = $address_type,
				a.verified = $verified,
				a.source = $source,
				a.created_at = $created_at,
				a.updated_at = $updated_at
			RETURN a.id
		`

		params := map[string]interface{}{
			"id":           address.ID,
			"street":       address.Street,
			"city":         address.City,
			"region":       address.Region,
			"postal_code":  address.PostalCode,
			"country":      address.Country,
			"formatted_ru": address.FormattedRu,
			"formatted_en": address.FormattedEn,
			"formatted_tt": address.FormattedTt,
			"latitude":     address.Latitude,
			"longitude":    address.Longitude,
			"address_type": string(address.AddressType),
			"verified":     address.Verified,
			"source":       address.Source,
			"created_at":   address.CreatedAt.Format(time.RFC3339),
			"updated_at":   address.UpdatedAt.Format(time.RFC3339),
		}

		result, err := tx.Run(ctx, addressCypher, params)
		if err != nil {
			return nil, fmt.Errorf("failed to execute address merge: %w", err)
		}

		if err := result.Err(); err != nil {
			return nil, fmt.Errorf("failed to consume address result: %w", err)
		}

		// Create Organization -> LOCATED_AT -> Address relationships using UNWIND for batch efficiency
		if len(orgIDs) > 0 {
			orgCypher := `
				MATCH (a:Address {id: $address_id})
				UNWIND $org_ids AS org_id
				MATCH (o:Organization {id: org_id})
				MERGE (o)-[:LOCATED_AT]->(a)
			`

			orgResult, err := tx.Run(ctx, orgCypher, map[string]interface{}{
				"address_id": address.ID,
				"org_ids":    orgIDs,
			})
			if err != nil {
				return nil, fmt.Errorf("failed to create organization relationships: %w", err)
			}

			if err := orgResult.Err(); err != nil {
				return nil, fmt.Errorf("failed to consume organization relationship result: %w", err)
			}
		}

		// Create Site -> LOCATED_AT -> Address relationships using UNWIND for batch efficiency
		if len(siteIDs) > 0 {
			siteCypher := `
				MATCH (a:Address {id: $address_id})
				UNWIND $site_ids AS site_id
				MATCH (s:Site {id: site_id})
				MERGE (s)-[:LOCATED_AT]->(a)
			`

			siteResult, err := tx.Run(ctx, siteCypher, map[string]interface{}{
				"address_id": address.ID,
				"site_ids":   siteIDs,
			})
			if err != nil {
				return nil, fmt.Errorf("failed to create site relationships: %w", err)
			}

			if err := siteResult.Err(); err != nil {
				return nil, fmt.Errorf("failed to consume site relationship result: %w", err)
			}
		}

		return nil, nil
	})

	return err
}

// DeleteFromGraph deletes an address from the graph database
func (r *GraphAddressRepository) DeleteFromGraph(ctx context.Context, id string) error {
	session := r.driver.NewSession(ctx, neo4j.SessionConfig{
		AccessMode:   neo4j.AccessModeWrite,
		DatabaseName: r.database,
	})
	defer session.Close(ctx)

	_, err := session.ExecuteWrite(ctx, func(tx neo4j.ManagedTransaction) (interface{}, error) {
		cypher := `
			MATCH (a:Address {id: $id})
			DETACH DELETE a
		`

		result, err := tx.Run(ctx, cypher, map[string]interface{}{"id": id})
		if err != nil {
			return nil, fmt.Errorf("failed to delete address: %w", err)
		}

		if err := result.Err(); err != nil {
			return nil, fmt.Errorf("failed to consume delete result: %w", err)
		}

		return nil, nil
	})

	return err
}

// GetByID retrieves an address from the graph
func (r *GraphAddressRepository) GetByID(ctx context.Context, id string) (*domain.Address, error) {
	session := r.driver.NewSession(ctx, neo4j.SessionConfig{
		AccessMode:   neo4j.AccessModeRead,
		DatabaseName: r.database,
	})
	defer session.Close(ctx)

	result, err := session.ExecuteRead(ctx, func(tx neo4j.ManagedTransaction) (interface{}, error) {
		cypher := `
			MATCH (a:Address {id: $id})
			RETURN a
		`

		result, err := tx.Run(ctx, cypher, map[string]interface{}{"id": id})
		if err != nil {
			return nil, err
		}

		if result.Next(ctx) {
			record := result.Record()
			node, ok := record.Get("a")
			if !ok {
				return nil, fmt.Errorf("address node not found in result")
			}

			return r.nodeToAddress(node.(neo4j.Node))
		}

		return nil, fmt.Errorf("address not found: %s", id)
	})

	if err != nil {
		return nil, err
	}

	return result.(*domain.Address), nil
}

// GetNearby finds addresses within a radius using spatial point.distance
func (r *GraphAddressRepository) GetNearby(ctx context.Context, lat, lng, radiusKm float64, limit int) ([]*domain.Address, error) {
	session := r.driver.NewSession(ctx, neo4j.SessionConfig{
		AccessMode:   neo4j.AccessModeRead,
		DatabaseName: r.database,
	})
	defer session.Close(ctx)

	result, err := session.ExecuteRead(ctx, func(tx neo4j.ManagedTransaction) (interface{}, error) {
		cypher := `
			MATCH (a:Address)
			WHERE a.latitude IS NOT NULL AND a.longitude IS NOT NULL
			WITH a, point.distance(
				point({latitude: $lat, longitude: $lng}),
				point({latitude: a.latitude, longitude: a.longitude})
			) / 1000.0 AS distance_km
			WHERE distance_km <= $radius_km
			RETURN a, distance_km
			ORDER BY distance_km
			LIMIT $limit
		`

		params := map[string]interface{}{
			"lat":       lat,
			"lng":       lng,
			"radius_km": radiusKm,
			"limit":     limit,
		}

		result, err := tx.Run(ctx, cypher, params)
		if err != nil {
			return nil, err
		}

		var addresses []*domain.Address
		for result.Next(ctx) {
			record := result.Record()
			node, ok := record.Get("a")
			if !ok {
				continue
			}

			address, err := r.nodeToAddress(node.(neo4j.Node))
			if err != nil {
				return nil, err
			}

			addresses = append(addresses, address)
		}

		if err := result.Err(); err != nil {
			return nil, err
		}

		return addresses, nil
	})

	if err != nil {
		return nil, err
	}

	return result.([]*domain.Address), nil
}

// nodeToAddress converts a Neo4j node to an Address domain object
func (r *GraphAddressRepository) nodeToAddress(node neo4j.Node) (*domain.Address, error) {
	props := node.Props

	address := &domain.Address{
		ID:          props["id"].(string),
		Street:      getStringProp(props, "street"),
		City:        getStringProp(props, "city"),
		Region:      getStringProp(props, "region"),
		PostalCode:  getStringProp(props, "postal_code"),
		Country:     getStringProp(props, "country"),
		FormattedRu: getStringProp(props, "formatted_ru"),
		FormattedEn: getStringProp(props, "formatted_en"),
		FormattedTt: getStringProp(props, "formatted_tt"),
		Source:      getStringProp(props, "source"),
		Verified:    getBoolProp(props, "verified"),
	}

	// Parse address type enum
	if typeStr, ok := props["address_type"].(string); ok {
		address.AddressType = domain.AddressType(typeStr)
	}

	// Parse numeric fields
	if val, ok := props["latitude"].(float64); ok {
		address.Latitude = val
	}
	if val, ok := props["longitude"].(float64); ok {
		address.Longitude = val
	}

	// Parse timestamps
	if createdAt, ok := props["created_at"].(string); ok {
		if t, err := time.Parse(time.RFC3339, createdAt); err == nil {
			address.CreatedAt = t
		}
	}
	if updatedAt, ok := props["updated_at"].(string); ok {
		if t, err := time.Parse(time.RFC3339, updatedAt); err == nil {
			address.UpdatedAt = t
		}
	}

	return address, nil
}