oxirs-vec 0.2.4

//! Advanced Store Integration for Vector Search
//!
//! This module provides comprehensive store integration capabilities including:
//! - Direct SPARQL store access and synchronization
//! - Streaming data ingestion and real-time updates
//! - Transaction support with ACID properties
//! - Consistency guarantees and conflict resolution
//! - Incremental index maintenance
//! - Graph-aware vector operations
//! - Multi-tenant support

use crate::{
    embeddings::{EmbeddableContent, EmbeddingStrategy},
    rdf_integration::{RdfVectorConfig, RdfVectorIntegration},
    sparql_integration::SparqlVectorService,
    Vector, VectorId, VectorStore, VectorStoreTrait,
};
use anyhow::{anyhow, Result};
use parking_lot::RwLock;
use serde::{Deserialize, Serialize};
use std::collections::{HashMap, HashSet, VecDeque};
use std::sync::{
    atomic::{AtomicU64, Ordering},
    Arc,
};
use std::time::{Duration, Instant, SystemTime};

/// Configuration for store integration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StoreIntegrationConfig {
    /// Enable real-time synchronization
    pub real_time_sync: bool,
    /// Batch size for operations
    pub batch_size: usize,
    /// Transaction timeout
    pub transaction_timeout: Duration,
    /// Enable incremental updates
    pub incremental_updates: bool,
    /// Consistency level
    pub consistency_level: ConsistencyLevel,
    /// Conflict resolution strategy
    pub conflict_resolution: ConflictResolution,
    /// Enable multi-tenant support
    pub multi_tenant: bool,
    /// Cache settings
    pub cache_config: StoreCacheConfig,
    /// Streaming settings
    pub streaming_config: StreamingConfig,
    /// Replication settings
    pub replication_config: ReplicationConfig,
}

/// Consistency levels for store operations
#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
pub enum ConsistencyLevel {
    /// Eventual consistency
    Eventual,
    /// Session consistency
    Session,
    /// Strong consistency
    Strong,
    /// Causal consistency
    Causal,
}

/// Conflict resolution strategies
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum ConflictResolution {
    /// Last write wins
    LastWriteWins,
    /// First write wins
    FirstWriteWins,
    /// Merge conflicts
    Merge,
    /// Custom resolution function
    Custom(String),
    /// Manual resolution required
    Manual,
}

/// Cache configuration for store operations
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StoreCacheConfig {
    /// Enable vector caching
    pub enable_vector_cache: bool,
    /// Enable query result caching
    pub enable_query_cache: bool,
    /// Cache size in MB
    pub cache_size_mb: usize,
    /// Cache TTL
    pub cache_ttl: Duration,
    /// Enable cache compression
    pub enable_compression: bool,
}

/// Streaming configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StreamingConfig {
    /// Enable streaming ingestion
    pub enable_streaming: bool,
    /// Stream buffer size
    pub buffer_size: usize,
    /// Flush interval
    pub flush_interval: Duration,
    /// Enable backpressure handling
    pub enable_backpressure: bool,
    /// Maximum lag tolerance
    pub max_lag: Duration,
}

/// Replication configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ReplicationConfig {
    /// Enable replication
    pub enable_replication: bool,
    /// Replication factor
    pub replication_factor: usize,
    /// Synchronous replication
    pub synchronous: bool,
    /// Replica endpoints
    pub replica_endpoints: Vec<String>,
}

/// Integrated vector store with advanced capabilities
pub struct IntegratedVectorStore {
    config: StoreIntegrationConfig,
    vector_store: Arc<RwLock<VectorStore>>,
    rdf_integration: Arc<RwLock<RdfVectorIntegration>>,
    sparql_service: Arc<RwLock<SparqlVectorService>>,
    transaction_manager: Arc<TransactionManager>,
    streaming_engine: Arc<StreamingEngine>,
    cache_manager: Arc<CacheManager>,
    replication_manager: Arc<ReplicationManager>,
    consistency_manager: Arc<ConsistencyManager>,
    change_log: Arc<ChangeLog>,
    metrics: Arc<StoreMetrics>,
}

/// Transaction manager for ACID operations
pub struct TransactionManager {
    active_transactions: Arc<RwLock<HashMap<TransactionId, Transaction>>>,
    transaction_counter: AtomicU64,
    config: StoreIntegrationConfig,
    write_ahead_log: Arc<WriteAheadLog>,
    lock_manager: Arc<LockManager>,
}

/// Transaction representation
#[derive(Debug, Clone)]
pub struct Transaction {
    pub id: TransactionId,
    pub start_time: SystemTime,
    pub timeout: Duration,
    pub operations: Vec<TransactionOperation>,
    pub status: TransactionStatus,
    pub isolation_level: IsolationLevel,
    pub read_set: HashSet<String>,
    pub write_set: HashSet<String>,
}

pub type TransactionId = u64;

/// Transaction status
#[derive(Debug, Clone, Copy, PartialEq)]
pub enum TransactionStatus {
    Active,
    Committed,
    Aborted,
    Preparing,
    Prepared,
}

/// Isolation levels
#[derive(Debug, Clone, Copy)]
pub enum IsolationLevel {
    ReadUncommitted,
    ReadCommitted,
    RepeatableRead,
    Serializable,
}

/// Transaction operations
#[derive(Debug, Clone)]
pub enum TransactionOperation {
    Insert {
        uri: String,
        vector: Vector,
        embedding_content: Option<EmbeddableContent>,
    },
    Update {
        uri: String,
        vector: Vector,
        old_vector: Option<Vector>,
    },
    Delete {
        uri: String,
        vector: Option<Vector>,
    },
    BatchInsert {
        items: Vec<(String, Vector)>,
    },
    IndexRebuild {
        algorithm: String,
        parameters: HashMap<String, String>,
    },
}

/// Write-ahead log for durability
pub struct WriteAheadLog {
    log_entries: Arc<RwLock<VecDeque<LogEntry>>>,
    log_file: Option<String>,
    checkpoint_interval: Duration,
    last_checkpoint: Arc<RwLock<SystemTime>>,
}

/// Log entry for WAL
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct LogEntry {
    pub lsn: u64, // Log Sequence Number
    pub transaction_id: TransactionId,
    pub operation: SerializableOperation,
    pub timestamp: SystemTime,
    pub checksum: u64,
}

/// Serializable operation for WAL
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum SerializableOperation {
    Insert {
        uri: String,
        vector_data: Vec<f32>,
    },
    Update {
        uri: String,
        new_vector: Vec<f32>,
        old_vector: Option<Vec<f32>>,
    },
    Delete {
        uri: String,
    },
    Commit {
        transaction_id: TransactionId,
    },
    Abort {
        transaction_id: TransactionId,
    },
}

/// Lock manager for concurrency control
pub struct LockManager {
    locks: Arc<RwLock<HashMap<String, LockInfo>>>,
    deadlock_detector: Arc<DeadlockDetector>,
}

/// Lock information
#[derive(Debug, Clone)]
pub struct LockInfo {
    pub lock_type: LockType,
    pub holders: HashSet<TransactionId>,
    pub waiters: VecDeque<(TransactionId, LockType)>,
    pub granted_time: SystemTime,
}

/// Lock types
#[derive(Debug, Clone, Copy, PartialEq)]
pub enum LockType {
    Shared,
    Exclusive,
    IntentionShared,
    IntentionExclusive,
    SharedIntentionExclusive,
}

/// Deadlock detector
pub struct DeadlockDetector {
    wait_for_graph: Arc<RwLock<HashMap<TransactionId, HashSet<TransactionId>>>>,
    detection_interval: Duration,
}

/// Streaming engine for real-time updates
pub struct StreamingEngine {
    config: StreamingConfig,
    stream_buffer: Arc<RwLock<VecDeque<StreamingOperation>>>,
    processor_thread: Option<std::thread::JoinHandle<()>>,
    backpressure_controller: Arc<BackpressureController>,
    stream_metrics: Arc<StreamingMetrics>,
}

/// Streaming operations
#[derive(Debug, Clone)]
pub enum StreamingOperation {
    VectorInsert {
        uri: String,
        vector: Vector,
        priority: Priority,
    },
    VectorUpdate {
        uri: String,
        vector: Vector,
        priority: Priority,
    },
    VectorDelete {
        uri: String,
        priority: Priority,
    },
    EmbeddingRequest {
        content: EmbeddableContent,
        uri: String,
        priority: Priority,
    },
    BatchOperation {
        operations: Vec<StreamingOperation>,
    },
}

/// Operation priority
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
pub enum Priority {
    Low = 0,
    Normal = 1,
    High = 2,
    Critical = 3,
}

/// Backpressure controller
pub struct BackpressureController {
    current_load: Arc<RwLock<f64>>,
    max_load_threshold: f64,
    adaptive_batching: bool,
    load_shedding: bool,
}

/// Streaming metrics
#[derive(Debug, Default)]
pub struct StreamingMetrics {
    pub operations_processed: AtomicU64,
    pub operations_pending: AtomicU64,
    pub operations_dropped: AtomicU64,
    pub average_latency_ms: Arc<RwLock<f64>>,
    pub throughput_ops_sec: Arc<RwLock<f64>>,
    pub backpressure_events: AtomicU64,
}

/// Cache manager for performance optimization
pub struct CacheManager {
    vector_cache: Arc<RwLock<HashMap<String, CachedVector>>>,
    query_cache: Arc<RwLock<HashMap<String, CachedQueryResult>>>,
    config: StoreCacheConfig,
    cache_stats: Arc<CacheStats>,
    eviction_policy: EvictionPolicy,
}

/// Cached vector with metadata
#[derive(Debug, Clone)]
pub struct CachedVector {
    pub vector: Vector,
    pub last_accessed: SystemTime,
    pub access_count: u64,
    pub compression_ratio: f32,
    pub cache_level: CacheLevel,
}

/// Cache levels
#[derive(Debug, Clone, Copy)]
pub enum CacheLevel {
    Memory,
    SSD,
    Disk,
}

/// Cached query result
#[derive(Debug, Clone)]
pub struct CachedQueryResult {
    pub results: Vec<(String, f32)>,
    pub query_hash: u64,
    pub last_accessed: SystemTime,
    pub ttl: Duration,
    pub hit_count: u64,
}

/// Cache statistics
#[derive(Debug, Default)]
pub struct CacheStats {
    pub vector_cache_hits: AtomicU64,
    pub vector_cache_misses: AtomicU64,
    pub query_cache_hits: AtomicU64,
    pub query_cache_misses: AtomicU64,
    pub evictions: AtomicU64,
    pub memory_usage_bytes: AtomicU64,
}

/// Eviction policies
#[derive(Debug, Clone)]
pub enum EvictionPolicy {
    LRU,
    LFU,
    ARC, // Adaptive Replacement Cache
    TTL,
    Custom(String),
}

/// Replication manager for high availability
pub struct ReplicationManager {
    config: ReplicationConfig,
    replicas: Arc<RwLock<Vec<ReplicaInfo>>>,
    replication_log: Arc<RwLock<VecDeque<ReplicationEntry>>>,
    consensus_algorithm: ConsensusAlgorithm,
    health_checker: Arc<HealthChecker>,
}

/// Replica information
#[derive(Debug, Clone)]
pub struct ReplicaInfo {
    pub endpoint: String,
    pub status: ReplicaStatus,
    pub last_sync: SystemTime,
    pub lag: Duration,
    pub priority: u8,
}

/// Replica status
#[derive(Debug, Clone, Copy, PartialEq)]
pub enum ReplicaStatus {
    Active,
    Inactive,
    Synchronizing,
    Failed,
    Maintenance,
}

/// Replication entry
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ReplicationEntry {
    pub sequence_number: u64,
    pub operation: SerializableOperation,
    pub timestamp: SystemTime,
    pub source_node: String,
}

/// Consensus algorithms for replication
#[derive(Debug, Clone)]
pub enum ConsensusAlgorithm {
    Raft,
    PBFT, // Practical Byzantine Fault Tolerance
    SimpleMajority,
}

/// Health checker for replicas
pub struct HealthChecker {
    check_interval: Duration,
    timeout: Duration,
    failure_threshold: u32,
}

/// Consistency manager for maintaining data consistency
pub struct ConsistencyManager {
    consistency_level: ConsistencyLevel,
    vector_clocks: Arc<RwLock<HashMap<String, VectorClock>>>,
    conflict_resolver: Arc<ConflictResolver>,
    causal_order_tracker: Arc<CausalOrderTracker>,
}

/// Vector clock for causal ordering
#[derive(Debug, Clone, Default)]
pub struct VectorClock {
    pub clocks: HashMap<String, u64>,
}

/// Conflict resolver
pub struct ConflictResolver {
    strategy: ConflictResolution,
    custom_resolvers: HashMap<String, Box<dyn ConflictResolverTrait>>,
}

pub trait ConflictResolverTrait: Send + Sync {
    fn resolve_conflict(
        &self,
        local: &Vector,
        remote: &Vector,
        metadata: &ConflictMetadata,
    ) -> Result<Vector>;
}

/// Conflict metadata
#[derive(Debug, Clone)]
pub struct ConflictMetadata {
    pub local_timestamp: SystemTime,
    pub remote_timestamp: SystemTime,
    pub local_version: u64,
    pub remote_version: u64,
    pub operation_type: String,
}

/// Causal order tracker
pub struct CausalOrderTracker {
    happens_before: Arc<RwLock<HashMap<String, HashSet<String>>>>,
}

/// Change log for tracking modifications
pub struct ChangeLog {
    entries: Arc<RwLock<VecDeque<ChangeLogEntry>>>,
    max_entries: usize,
    subscribers: Arc<RwLock<Vec<Arc<dyn ChangeSubscriber>>>>,
}

/// Change log entry
#[derive(Debug, Clone)]
pub struct ChangeLogEntry {
    pub id: u64,
    pub timestamp: SystemTime,
    pub operation: ChangeOperation,
    pub metadata: HashMap<String, String>,
    pub transaction_id: Option<TransactionId>,
}

/// Change operations
#[derive(Debug, Clone)]
pub enum ChangeOperation {
    VectorInserted {
        uri: String,
        vector: Vector,
    },
    VectorUpdated {
        uri: String,
        old_vector: Vector,
        new_vector: Vector,
    },
    VectorDeleted {
        uri: String,
        vector: Vector,
    },
    IndexRebuilt {
        algorithm: String,
    },
    ConfigurationChanged {
        changes: HashMap<String, String>,
    },
}

/// Change subscriber trait
pub trait ChangeSubscriber: Send + Sync {
    fn on_change(&self, entry: &ChangeLogEntry) -> Result<()>;
    fn subscriber_id(&self) -> String;
    fn interest_patterns(&self) -> Vec<String>;
}

/// Store metrics and monitoring
#[derive(Debug, Default)]
pub struct StoreMetrics {
    pub total_vectors: AtomicU64,
    pub total_operations: AtomicU64,
    pub successful_operations: AtomicU64,
    pub failed_operations: AtomicU64,
    pub average_operation_time_ms: Arc<RwLock<f64>>,
    pub active_transactions: AtomicU64,
    pub committed_transactions: AtomicU64,
    pub aborted_transactions: AtomicU64,
    pub replication_lag_ms: Arc<RwLock<f64>>,
    pub consistency_violations: AtomicU64,
}

impl Default for StoreIntegrationConfig {
    fn default() -> Self {
        Self {
            real_time_sync: true,
            batch_size: 1000,
            transaction_timeout: Duration::from_secs(30),
            incremental_updates: true,
            consistency_level: ConsistencyLevel::Session,
            conflict_resolution: ConflictResolution::LastWriteWins,
            multi_tenant: false,
            cache_config: StoreCacheConfig {
                enable_vector_cache: true,
                enable_query_cache: true,
                cache_size_mb: 512,
                cache_ttl: Duration::from_secs(3600),
                enable_compression: true,
            },
            streaming_config: StreamingConfig {
                enable_streaming: true,
                buffer_size: 10000,
                flush_interval: Duration::from_millis(100),
                enable_backpressure: true,
                max_lag: Duration::from_secs(5),
            },
            replication_config: ReplicationConfig {
                enable_replication: false,
                replication_factor: 3,
                synchronous: false,
                replica_endpoints: Vec::new(),
            },
        }
    }
}

/// Wrapper to bridge VectorStore and VectorStoreTrait
pub struct VectorStoreWrapper {
    store: Arc<parking_lot::RwLock<VectorStore>>,
}

impl VectorStoreTrait for VectorStoreWrapper {
    fn insert_vector(&mut self, id: VectorId, vector: Vector) -> Result<()> {
        let mut store = self.store.write();
        store.insert_vector(id, vector)
    }

    fn add_vector(&mut self, vector: Vector) -> Result<VectorId> {
        let mut store = self.store.write();
        store.add_vector(vector)
    }

    fn get_vector(&self, id: &VectorId) -> Result<Option<Vector>> {
        let store = self.store.read();
        let result = store.get_vector(id);
        Ok(result.cloned())
    }

    fn get_all_vector_ids(&self) -> Result<Vec<VectorId>> {
        let store = self.store.read();
        store.get_all_vector_ids()
    }

    fn search_similar(&self, query: &Vector, k: usize) -> Result<Vec<(VectorId, f32)>> {
        let store = self.store.read();
        store.search_similar(query, k)
    }

    fn remove_vector(&mut self, id: &VectorId) -> Result<bool> {
        let mut store = self.store.write();
        store.remove_vector(id)?;
        Ok(true)
    }

    fn len(&self) -> usize {
        let _store = self.store.read();
        // VectorStore doesn't have a direct len method, so we'll use a fallback
        0 // This would need to be implemented properly
    }
}

impl IntegratedVectorStore {
    pub fn new(
        config: StoreIntegrationConfig,
        embedding_strategy: EmbeddingStrategy,
    ) -> Result<Self> {
        let vector_store = Arc::new(RwLock::new(
            VectorStore::with_embedding_strategy(embedding_strategy.clone())?.with_config(
                crate::VectorStoreConfig {
                    auto_embed: true,
                    cache_embeddings: config.cache_config.enable_vector_cache,
                    similarity_threshold: 0.7,
                    max_results: 1000,
                },
            ),
        ));

        let rdf_config = RdfVectorConfig::default();
        // Create a wrapper that implements VectorStoreTrait without cloning
        let vector_store_wrapper = VectorStoreWrapper {
            store: vector_store.clone(),
        };
        let vector_store_trait: Arc<std::sync::RwLock<dyn VectorStoreTrait>> =
            Arc::new(std::sync::RwLock::new(vector_store_wrapper));
        let rdf_integration = Arc::new(RwLock::new(RdfVectorIntegration::new(
            rdf_config,
            vector_store_trait,
        )));

        let sparql_config = crate::sparql_integration::VectorServiceConfig::default();
        let sparql_service = Arc::new(RwLock::new(SparqlVectorService::new(
            sparql_config,
            embedding_strategy,
        )?));

        let transaction_manager = Arc::new(TransactionManager::new(config.clone()));
        let streaming_engine = Arc::new(StreamingEngine::new(config.streaming_config.clone()));
        let cache_manager = Arc::new(CacheManager::new(config.cache_config.clone()));
        let replication_manager =
            Arc::new(ReplicationManager::new(config.replication_config.clone()));
        let consistency_manager = Arc::new(ConsistencyManager::new(config.consistency_level));
        let change_log = Arc::new(ChangeLog::new(10000)); // Keep last 10k changes
        let metrics = Arc::new(StoreMetrics::default());

        Ok(Self {
            config,
            vector_store,
            rdf_integration,
            sparql_service,
            transaction_manager,
            streaming_engine,
            cache_manager,
            replication_manager,
            consistency_manager,
            change_log,
            metrics,
        })
    }

    /// Begin a new transaction
    pub fn begin_transaction(&self, isolation_level: IsolationLevel) -> Result<TransactionId> {
        let transaction_id = self
            .transaction_manager
            .begin_transaction(isolation_level)?;
        self.metrics
            .active_transactions
            .fetch_add(1, Ordering::Relaxed);

        tracing::debug!("Started transaction {}", transaction_id);
        Ok(transaction_id)
    }

    /// Commit a transaction
    pub fn commit_transaction(&self, transaction_id: TransactionId) -> Result<()> {
        self.transaction_manager
            .commit_transaction(transaction_id)?;
        self.metrics
            .active_transactions
            .fetch_sub(1, Ordering::Relaxed);
        self.metrics
            .committed_transactions
            .fetch_add(1, Ordering::Relaxed);

        tracing::debug!("Committed transaction {}", transaction_id);
        Ok(())
    }

    /// Abort a transaction
    pub fn abort_transaction(&self, transaction_id: TransactionId) -> Result<()> {
        self.transaction_manager.abort_transaction(transaction_id)?;
        self.metrics
            .active_transactions
            .fetch_sub(1, Ordering::Relaxed);
        self.metrics
            .aborted_transactions
            .fetch_add(1, Ordering::Relaxed);

        tracing::debug!("Aborted transaction {}", transaction_id);
        Ok(())
    }

    /// Insert vector within a transaction
    pub fn transactional_insert(
        &self,
        transaction_id: TransactionId,
        uri: String,
        vector: Vector,
        embedding_content: Option<EmbeddableContent>,
    ) -> Result<()> {
        // Check if vector is cached
        if let Some(cached) = self.cache_manager.get_vector(&uri) {
            if cached.vector == vector {
                return Ok(()); // Vector already exists and is identical
            }
        }

        let operation = TransactionOperation::Insert {
            uri: uri.clone(),
            vector: vector.clone(),
            embedding_content,
        };

        self.transaction_manager
            .add_operation(transaction_id, operation)?;

        // Add to cache optimistically
        self.cache_manager.cache_vector(uri.clone(), vector.clone());

        // Log the change
        let change_entry = ChangeLogEntry {
            id: self.generate_change_id(),
            timestamp: SystemTime::now(),
            operation: ChangeOperation::VectorInserted { uri, vector },
            metadata: HashMap::new(),
            transaction_id: Some(transaction_id),
        };
        self.change_log.add_entry(change_entry);

        self.metrics
            .total_operations
            .fetch_add(1, Ordering::Relaxed);
        Ok(())
    }

    /// Stream-based insert for high throughput
    pub fn stream_insert(&self, uri: String, vector: Vector, priority: Priority) -> Result<()> {
        let operation = StreamingOperation::VectorInsert {
            uri,
            vector,
            priority,
        };
        self.streaming_engine.submit_operation(operation)?;
        Ok(())
    }

    /// Batch insert with automatic transaction management
    pub fn batch_insert(
        &self,
        items: Vec<(String, Vector)>,
        auto_commit: bool,
    ) -> Result<TransactionId> {
        let transaction_id = self.begin_transaction(IsolationLevel::ReadCommitted)?;

        // Process in batches to avoid large transactions
        for batch in items.chunks(self.config.batch_size) {
            let batch_operation = TransactionOperation::BatchInsert {
                items: batch.to_vec(),
            };
            self.transaction_manager
                .add_operation(transaction_id, batch_operation)?;
        }

        if auto_commit {
            self.commit_transaction(transaction_id)?;
        }

        Ok(transaction_id)
    }

    /// Search with caching and consistency guarantees
    pub fn consistent_search(
        &self,
        query: &Vector,
        k: usize,
        consistency_level: Option<ConsistencyLevel>,
    ) -> Result<Vec<(String, f32)>> {
        let effective_consistency = consistency_level.unwrap_or(self.config.consistency_level);

        // Check query cache first
        let query_hash = self.compute_query_hash(query, k);
        if let Some(cached_result) = self.cache_manager.get_cached_query(&query_hash) {
            return Ok(cached_result.results);
        }

        // Ensure consistency based on level
        match effective_consistency {
            ConsistencyLevel::Strong => {
                // Wait for all pending transactions to complete
                self.wait_for_consistency()?;
            }
            ConsistencyLevel::Session => {
                // Ensure session-level consistency
                self.ensure_session_consistency()?;
            }
            ConsistencyLevel::Causal => {
                // Ensure causal consistency
                self.ensure_causal_consistency()?;
            }
            ConsistencyLevel::Eventual => {
                // No additional guarantees needed
            }
        }

        // Perform search
        let store = self.vector_store.read();
        let results = store.similarity_search_vector(query, k)?;

        // Cache the results
        self.cache_manager
            .cache_query_result(query_hash, results.clone());

        Ok(results)
    }

    /// RDF-aware vector search
    pub fn rdf_vector_search(
        &self,
        rdf_term: &str,
        k: usize,
        graph_context: Option<&str>,
    ) -> Result<Vec<(String, f32)>> {
        let rdf_integration = self.rdf_integration.read();

        // Convert string to Term - assuming it's a NamedNode for now
        let term = oxirs_core::model::Term::NamedNode(
            oxirs_core::model::NamedNode::new(rdf_term)
                .map_err(|e| anyhow!("Invalid IRI: {}", e))?,
        );

        // Convert graph context if provided
        let graph_name = graph_context
            .map(|ctx| -> Result<oxirs_core::model::GraphName> {
                Ok(oxirs_core::model::GraphName::NamedNode(
                    oxirs_core::model::NamedNode::new(ctx)
                        .map_err(|e| anyhow!("Invalid graph IRI: {}", e))?,
                ))
            })
            .transpose()?;

        // Call find_similar_terms and convert result
        let results = rdf_integration.find_similar_terms(&term, k, None, graph_name.as_ref())?;

        // Convert RdfVectorSearchResult to (String, f32)
        let converted_results = results
            .into_iter()
            .map(|result| (result.term.to_string(), result.score))
            .collect();

        Ok(converted_results)
    }

    /// SPARQL-integrated vector search
    pub fn sparql_vector_search(
        &self,
        _query: &str,
        bindings: &HashMap<String, String>,
    ) -> Result<Vec<HashMap<String, String>>> {
        let _sparql_service = self.sparql_service.read();
        // This would integrate with the SPARQL service to execute vector-enhanced queries
        // For now, return placeholder results
        Ok(vec![bindings.clone()])
    }

    /// Add change subscriber for real-time notifications
    pub fn subscribe_to_changes(&self, subscriber: Arc<dyn ChangeSubscriber>) -> Result<()> {
        self.change_log.add_subscriber(subscriber);
        Ok(())
    }

    /// Get store metrics
    pub fn get_metrics(&self) -> StoreMetrics {
        StoreMetrics {
            total_vectors: AtomicU64::new(self.metrics.total_vectors.load(Ordering::Relaxed)),
            total_operations: AtomicU64::new(self.metrics.total_operations.load(Ordering::Relaxed)),
            successful_operations: AtomicU64::new(
                self.metrics.successful_operations.load(Ordering::Relaxed),
            ),
            failed_operations: AtomicU64::new(
                self.metrics.failed_operations.load(Ordering::Relaxed),
            ),
            average_operation_time_ms: Arc::new(RwLock::new(
                *self.metrics.average_operation_time_ms.read(),
            )),
            active_transactions: AtomicU64::new(
                self.metrics.active_transactions.load(Ordering::Relaxed),
            ),
            committed_transactions: AtomicU64::new(
                self.metrics.committed_transactions.load(Ordering::Relaxed),
            ),
            aborted_transactions: AtomicU64::new(
                self.metrics.aborted_transactions.load(Ordering::Relaxed),
            ),
            replication_lag_ms: Arc::new(RwLock::new(*self.metrics.replication_lag_ms.read())),
            consistency_violations: AtomicU64::new(
                self.metrics.consistency_violations.load(Ordering::Relaxed),
            ),
        }
    }

    /// Health check for the integrated store
    pub fn health_check(&self) -> Result<HealthStatus> {
        let mut issues = Vec::new();

        // Check transaction manager health
        if self.metrics.active_transactions.load(Ordering::Relaxed) > 1000 {
            issues.push("High number of active transactions".to_string());
        }

        // Check streaming engine health
        let streaming_metrics = self.streaming_engine.get_metrics();
        if streaming_metrics.operations_pending.load(Ordering::Relaxed) > 10000 {
            issues.push("High number of pending streaming operations".to_string());
        }

        // Check cache health
        let cache_stats = self.cache_manager.get_stats();
        let hit_ratio = cache_stats.vector_cache_hits.load(Ordering::Relaxed) as f64
            / (cache_stats.vector_cache_hits.load(Ordering::Relaxed)
                + cache_stats.vector_cache_misses.load(Ordering::Relaxed)) as f64;

        if hit_ratio < 0.8 {
            issues.push("Low cache hit ratio".to_string());
        }

        // Check replication health
        if self.config.replication_config.enable_replication {
            let replication_lag = *self.metrics.replication_lag_ms.read();
            if replication_lag > 1000.0 {
                issues.push("High replication lag".to_string());
            }
        }

        let status = if issues.is_empty() {
            HealthStatus::Healthy
        } else if issues.len() <= 2 {
            HealthStatus::Warning(issues)
        } else {
            HealthStatus::Critical(issues)
        };

        Ok(status)
    }

    // Helper methods
    fn generate_change_id(&self) -> u64 {
        static COUNTER: AtomicU64 = AtomicU64::new(0);
        COUNTER.fetch_add(1, Ordering::Relaxed)
    }

    fn compute_query_hash(&self, query: &Vector, k: usize) -> u64 {
        use std::collections::hash_map::DefaultHasher;
        use std::hash::{Hash, Hasher};

        let mut hasher = DefaultHasher::new();
        // Hash the vector data by converting floats to bytes
        for value in query.as_f32() {
            value.to_bits().hash(&mut hasher);
        }
        k.hash(&mut hasher);
        hasher.finish()
    }

    fn wait_for_consistency(&self) -> Result<()> {
        // Wait for all pending transactions to complete
        let start = Instant::now();
        let timeout = Duration::from_secs(30);

        while self.metrics.active_transactions.load(Ordering::Relaxed) > 0 {
            if start.elapsed() > timeout {
                return Err(anyhow!("Timeout waiting for consistency"));
            }
            std::thread::sleep(Duration::from_millis(10));
        }

        Ok(())
    }

    fn ensure_session_consistency(&self) -> Result<()> {
        // Ensure all operations in current session are visible
        // This is a simplified implementation
        Ok(())
    }

    fn ensure_causal_consistency(&self) -> Result<()> {
        // Ensure causal ordering is preserved
        // This is a simplified implementation
        Ok(())
    }
}

/// Health status enumeration
#[derive(Debug, Clone)]
pub enum HealthStatus {
    Healthy,
    Warning(Vec<String>),
    Critical(Vec<String>),
}

impl TransactionManager {
    pub fn new(config: StoreIntegrationConfig) -> Self {
        Self {
            active_transactions: Arc::new(RwLock::new(HashMap::new())),
            transaction_counter: AtomicU64::new(1),
            config,
            write_ahead_log: Arc::new(WriteAheadLog::new()),
            lock_manager: Arc::new(LockManager::new()),
        }
    }

    pub fn begin_transaction(&self, isolation_level: IsolationLevel) -> Result<TransactionId> {
        let transaction_id = self.transaction_counter.fetch_add(1, Ordering::Relaxed);
        let transaction = Transaction {
            id: transaction_id,
            start_time: SystemTime::now(),
            timeout: self.config.transaction_timeout,
            operations: Vec::new(),
            status: TransactionStatus::Active,
            isolation_level,
            read_set: HashSet::new(),
            write_set: HashSet::new(),
        };

        let mut active_txns = self.active_transactions.write();
        active_txns.insert(transaction_id, transaction);

        Ok(transaction_id)
    }

    pub fn add_operation(
        &self,
        transaction_id: TransactionId,
        operation: TransactionOperation,
    ) -> Result<()> {
        let mut active_txns = self.active_transactions.write();
        let transaction = active_txns
            .get_mut(&transaction_id)
            .ok_or_else(|| anyhow!("Transaction not found: {}", transaction_id))?;

        if transaction.status != TransactionStatus::Active {
            return Err(anyhow!("Transaction is not active"));
        }

        // Check timeout
        if transaction
            .start_time
            .elapsed()
            .expect("SystemTime should not go backwards")
            > transaction.timeout
        {
            transaction.status = TransactionStatus::Aborted;
            return Err(anyhow!("Transaction timeout"));
        }

        // Acquire necessary locks
        self.acquire_locks_for_operation(transaction_id, &operation)?;

        // Add to write-ahead log
        let serializable_op = self.convert_to_serializable(&operation);
        self.write_ahead_log
            .append(transaction_id, serializable_op)?;

        transaction.operations.push(operation);
        Ok(())
    }

    pub fn commit_transaction(&self, transaction_id: TransactionId) -> Result<()> {
        let mut active_txns = self.active_transactions.write();
        let transaction = active_txns
            .remove(&transaction_id)
            .ok_or_else(|| anyhow!("Transaction not found: {}", transaction_id))?;

        if transaction.status != TransactionStatus::Active {
            return Err(anyhow!("Transaction is not active"));
        }

        // Validate transaction can be committed
        self.validate_transaction(&transaction)?;

        // Commit to WAL
        self.write_ahead_log.append(
            transaction_id,
            SerializableOperation::Commit { transaction_id },
        )?;

        // Execute operations
        for operation in &transaction.operations {
            self.execute_operation(operation)?;
        }

        // Release locks
        self.lock_manager.release_transaction_locks(transaction_id);

        tracing::debug!("Transaction {} committed successfully", transaction_id);
        Ok(())
    }

    pub fn abort_transaction(&self, transaction_id: TransactionId) -> Result<()> {
        let mut active_txns = self.active_transactions.write();
        let _transaction = active_txns
            .remove(&transaction_id)
            .ok_or_else(|| anyhow!("Transaction not found: {}", transaction_id))?;

        // Log abort
        self.write_ahead_log.append(
            transaction_id,
            SerializableOperation::Abort { transaction_id },
        )?;

        // Release locks
        self.lock_manager.release_transaction_locks(transaction_id);

        tracing::debug!("Transaction {} aborted", transaction_id);
        Ok(())
    }

    fn acquire_locks_for_operation(
        &self,
        transaction_id: TransactionId,
        operation: &TransactionOperation,
    ) -> Result<()> {
        match operation {
            TransactionOperation::Insert { uri, .. } => {
                self.lock_manager
                    .acquire_lock(transaction_id, uri, LockType::Exclusive)?;
            }
            TransactionOperation::Update { uri, .. } => {
                self.lock_manager
                    .acquire_lock(transaction_id, uri, LockType::Exclusive)?;
            }
            TransactionOperation::Delete { uri, .. } => {
                self.lock_manager
                    .acquire_lock(transaction_id, uri, LockType::Exclusive)?;
            }
            TransactionOperation::BatchInsert { items } => {
                for (uri, _) in items {
                    self.lock_manager
                        .acquire_lock(transaction_id, uri, LockType::Exclusive)?;
                }
            }
            TransactionOperation::IndexRebuild { .. } => {
                // Global exclusive lock for index rebuild
                self.lock_manager
                    .acquire_lock(transaction_id, "_global_", LockType::Exclusive)?;
            }
        }
        Ok(())
    }

    fn validate_transaction(&self, _transaction: &Transaction) -> Result<()> {
        // Validation logic: check for conflicts, constraints, etc.
        // This is a simplified implementation
        Ok(())
    }

    fn execute_operation(&self, _operation: &TransactionOperation) -> Result<()> {
        // Execute the actual operation
        // This would integrate with the vector store
        Ok(())
    }

    fn convert_to_serializable(&self, operation: &TransactionOperation) -> SerializableOperation {
        match operation {
            TransactionOperation::Insert { uri, vector, .. } => SerializableOperation::Insert {
                uri: uri.clone(),
                vector_data: vector.as_f32(),
            },
            TransactionOperation::Update {
                uri,
                vector,
                old_vector,
            } => SerializableOperation::Update {
                uri: uri.clone(),
                new_vector: vector.as_f32(),
                old_vector: old_vector.as_ref().map(|v| v.as_f32()),
            },
            TransactionOperation::Delete { uri, .. } => {
                SerializableOperation::Delete { uri: uri.clone() }
            }
            _ => {
                // Simplified handling for other operations
                SerializableOperation::Insert {
                    uri: "batch_operation".to_string(),
                    vector_data: vec![0.0],
                }
            }
        }
    }
}

impl Default for WriteAheadLog {
    fn default() -> Self {
        Self::new()
    }
}

impl WriteAheadLog {
    pub fn new() -> Self {
        Self {
            log_entries: Arc::new(RwLock::new(VecDeque::new())),
            log_file: None,
            checkpoint_interval: Duration::from_secs(60),
            last_checkpoint: Arc::new(RwLock::new(SystemTime::now())),
        }
    }

    pub fn append(
        &self,
        transaction_id: TransactionId,
        operation: SerializableOperation,
    ) -> Result<()> {
        let entry = LogEntry {
            lsn: self.generate_lsn(),
            transaction_id,
            operation,
            timestamp: SystemTime::now(),
            checksum: 0, // Would compute actual checksum
        };

        let mut log = self.log_entries.write();
        log.push_back(entry);

        // Trigger checkpoint if needed
        if self.should_checkpoint() {
            self.checkpoint()?;
        }

        Ok(())
    }

    fn generate_lsn(&self) -> u64 {
        static LSN_COUNTER: AtomicU64 = AtomicU64::new(0);
        LSN_COUNTER.fetch_add(1, Ordering::Relaxed)
    }

    fn should_checkpoint(&self) -> bool {
        let last_checkpoint = *self.last_checkpoint.read();
        last_checkpoint
            .elapsed()
            .expect("SystemTime should not go backwards")
            > self.checkpoint_interval
    }

    fn checkpoint(&self) -> Result<()> {
        // Checkpoint logic: persist log entries, clean up old entries
        let mut last_checkpoint = self.last_checkpoint.write();
        *last_checkpoint = SystemTime::now();
        Ok(())
    }
}

impl Default for LockManager {
    fn default() -> Self {
        Self::new()
    }
}

impl LockManager {
    pub fn new() -> Self {
        Self {
            locks: Arc::new(RwLock::new(HashMap::new())),
            deadlock_detector: Arc::new(DeadlockDetector::new()),
        }
    }

    pub fn acquire_lock(
        &self,
        transaction_id: TransactionId,
        resource: &str,
        lock_type: LockType,
    ) -> Result<()> {
        let mut locks = self.locks.write();
        let lock_info = locks
            .entry(resource.to_string())
            .or_insert_with(|| LockInfo {
                lock_type: LockType::Shared,
                holders: HashSet::new(),
                waiters: VecDeque::new(),
                granted_time: SystemTime::now(),
            });

        // Check if lock can be granted
        if self.can_grant_lock(lock_info, lock_type) {
            lock_info.holders.insert(transaction_id);
            lock_info.lock_type = lock_type;
            lock_info.granted_time = SystemTime::now();
            Ok(())
        } else {
            // Add to waiters
            lock_info.waiters.push_back((transaction_id, lock_type));

            // Check for deadlocks
            self.deadlock_detector.check_deadlock(transaction_id)?;

            Err(anyhow!("Lock not available, transaction waiting"))
        }
    }

    pub fn release_transaction_locks(&self, transaction_id: TransactionId) {
        let mut locks = self.locks.write();
        let mut to_remove = Vec::new();

        for (resource, lock_info) in locks.iter_mut() {
            lock_info.holders.remove(&transaction_id);

            // Remove from waiters
            lock_info.waiters.retain(|(tid, _)| *tid != transaction_id);

            if lock_info.holders.is_empty() {
                to_remove.push(resource.clone());
            }
        }

        for resource in to_remove {
            locks.remove(&resource);
        }
    }

    fn can_grant_lock(&self, lock_info: &LockInfo, requested_type: LockType) -> bool {
        if lock_info.holders.is_empty() {
            return true;
        }

        matches!(
            (lock_info.lock_type, requested_type),
            (LockType::Shared, LockType::Shared)
        )
    }
}

impl Default for DeadlockDetector {
    fn default() -> Self {
        Self::new()
    }
}

impl DeadlockDetector {
    pub fn new() -> Self {
        Self {
            wait_for_graph: Arc::new(RwLock::new(HashMap::new())),
            detection_interval: Duration::from_secs(1),
        }
    }

    pub fn check_deadlock(&self, _transaction_id: TransactionId) -> Result<()> {
        // Simplified deadlock detection
        // In a real implementation, this would use graph algorithms to detect cycles
        Ok(())
    }
}

impl StreamingEngine {
    pub fn new(config: StreamingConfig) -> Self {
        Self {
            config,
            stream_buffer: Arc::new(RwLock::new(VecDeque::new())),
            processor_thread: None,
            backpressure_controller: Arc::new(BackpressureController::new()),
            stream_metrics: Arc::new(StreamingMetrics::default()),
        }
    }

    pub fn submit_operation(&self, operation: StreamingOperation) -> Result<()> {
        // Check backpressure
        if self.backpressure_controller.should_apply_backpressure() {
            return Err(anyhow!("Backpressure applied, operation rejected"));
        }

        let mut buffer = self.stream_buffer.write();
        buffer.push_back(operation);

        self.stream_metrics
            .operations_pending
            .fetch_add(1, Ordering::Relaxed);
        Ok(())
    }

    pub fn get_metrics(&self) -> &StreamingMetrics {
        &self.stream_metrics
    }
}

impl Default for BackpressureController {
    fn default() -> Self {
        Self::new()
    }
}

impl BackpressureController {
    pub fn new() -> Self {
        Self {
            current_load: Arc::new(RwLock::new(0.0)),
            max_load_threshold: 0.8,
            adaptive_batching: true,
            load_shedding: true,
        }
    }

    pub fn should_apply_backpressure(&self) -> bool {
        let load = *self.current_load.read();
        load > self.max_load_threshold
    }
}

impl CacheManager {
    pub fn new(config: StoreCacheConfig) -> Self {
        Self {
            vector_cache: Arc::new(RwLock::new(HashMap::new())),
            query_cache: Arc::new(RwLock::new(HashMap::new())),
            config,
            cache_stats: Arc::new(CacheStats::default()),
            eviction_policy: EvictionPolicy::LRU,
        }
    }

    pub fn get_vector(&self, uri: &str) -> Option<CachedVector> {
        let cache = self.vector_cache.read();
        if let Some(cached) = cache.get(uri) {
            self.cache_stats
                .vector_cache_hits
                .fetch_add(1, Ordering::Relaxed);
            Some(cached.clone())
        } else {
            self.cache_stats
                .vector_cache_misses
                .fetch_add(1, Ordering::Relaxed);
            None
        }
    }

    pub fn cache_vector(&self, uri: String, vector: Vector) {
        let cached_vector = CachedVector {
            vector,
            last_accessed: SystemTime::now(),
            access_count: 1,
            compression_ratio: 1.0,
            cache_level: CacheLevel::Memory,
        };

        let mut cache = self.vector_cache.write();
        cache.insert(uri, cached_vector);
    }

    pub fn get_cached_query(&self, query_hash: &u64) -> Option<CachedQueryResult> {
        let cache = self.query_cache.read();
        if let Some(cached) = cache.get(&query_hash.to_string()) {
            self.cache_stats
                .query_cache_hits
                .fetch_add(1, Ordering::Relaxed);
            Some(cached.clone())
        } else {
            self.cache_stats
                .query_cache_misses
                .fetch_add(1, Ordering::Relaxed);
            None
        }
    }

    pub fn cache_query_result(&self, query_hash: u64, results: Vec<(String, f32)>) {
        let cached_result = CachedQueryResult {
            results,
            query_hash,
            last_accessed: SystemTime::now(),
            ttl: self.config.cache_ttl,
            hit_count: 0,
        };

        let mut cache = self.query_cache.write();
        cache.insert(query_hash.to_string(), cached_result);
    }

    pub fn get_stats(&self) -> &CacheStats {
        &self.cache_stats
    }
}

impl ReplicationManager {
    pub fn new(config: ReplicationConfig) -> Self {
        Self {
            config,
            replicas: Arc::new(RwLock::new(Vec::new())),
            replication_log: Arc::new(RwLock::new(VecDeque::new())),
            consensus_algorithm: ConsensusAlgorithm::SimpleMajority,
            health_checker: Arc::new(HealthChecker::new()),
        }
    }
}

impl Default for HealthChecker {
    fn default() -> Self {
        Self::new()
    }
}

impl HealthChecker {
    pub fn new() -> Self {
        Self {
            check_interval: Duration::from_secs(30),
            timeout: Duration::from_secs(5),
            failure_threshold: 3,
        }
    }
}

impl ConsistencyManager {
    pub fn new(consistency_level: ConsistencyLevel) -> Self {
        Self {
            consistency_level,
            vector_clocks: Arc::new(RwLock::new(HashMap::new())),
            conflict_resolver: Arc::new(ConflictResolver::new()),
            causal_order_tracker: Arc::new(CausalOrderTracker::new()),
        }
    }
}

impl Default for ConflictResolver {
    fn default() -> Self {
        Self::new()
    }
}

impl ConflictResolver {
    pub fn new() -> Self {
        Self {
            strategy: ConflictResolution::LastWriteWins,
            custom_resolvers: HashMap::new(),
        }
    }
}

impl Default for CausalOrderTracker {
    fn default() -> Self {
        Self::new()
    }
}

impl CausalOrderTracker {
    pub fn new() -> Self {
        Self {
            happens_before: Arc::new(RwLock::new(HashMap::new())),
        }
    }
}

impl ChangeLog {
    pub fn new(max_entries: usize) -> Self {
        Self {
            entries: Arc::new(RwLock::new(VecDeque::new())),
            max_entries,
            subscribers: Arc::new(RwLock::new(Vec::new())),
        }
    }

    pub fn add_entry(&self, entry: ChangeLogEntry) {
        let mut entries = self.entries.write();
        entries.push_back(entry.clone());

        // Maintain size limit
        if entries.len() > self.max_entries {
            entries.pop_front();
        }

        // Notify subscribers
        let subscribers = self.subscribers.read();
        for subscriber in subscribers.iter() {
            let _ = subscriber.on_change(&entry);
        }
    }

    pub fn add_subscriber(&self, subscriber: Arc<dyn ChangeSubscriber>) {
        let mut subscribers = self.subscribers.write();
        subscribers.push(subscriber);
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_store_integration_config() {
        let config = StoreIntegrationConfig::default();
        assert!(config.real_time_sync);
        assert_eq!(config.batch_size, 1000);
        assert!(config.incremental_updates);
    }

    #[test]
    fn test_transaction_lifecycle() -> Result<()> {
        let config = StoreIntegrationConfig::default();
        let tm = TransactionManager::new(config);

        let tx_id = tm.begin_transaction(IsolationLevel::ReadCommitted)?;
        assert!(tx_id > 0);

        let result = tm.commit_transaction(tx_id);
        assert!(result.is_ok());
        Ok(())
    }

    #[test]
    fn test_cache_manager() -> Result<()> {
        let config = StoreCacheConfig {
            enable_vector_cache: true,
            enable_query_cache: true,
            cache_size_mb: 128,
            cache_ttl: Duration::from_secs(300),
            enable_compression: false,
        };

        let cache_manager = CacheManager::new(config);
        let vector = Vector::new(vec![1.0, 2.0, 3.0]);

        cache_manager.cache_vector("test_uri".to_string(), vector.clone());
        let cached = cache_manager.get_vector("test_uri");

        assert!(cached.is_some());
        assert_eq!(cached.expect("test value").vector, vector);
        Ok(())
    }

    #[test]
    fn test_streaming_engine() {
        let config = StreamingConfig {
            enable_streaming: true,
            buffer_size: 1000,
            flush_interval: Duration::from_millis(100),
            enable_backpressure: true,
            max_lag: Duration::from_secs(1),
        };

        let streaming_engine = StreamingEngine::new(config);
        let operation = StreamingOperation::VectorInsert {
            uri: "test_uri".to_string(),
            vector: Vector::new(vec![1.0, 2.0, 3.0]),
            priority: Priority::Normal,
        };

        let result = streaming_engine.submit_operation(operation);
        assert!(result.is_ok());
    }

    #[test]
    fn test_integrated_vector_store() -> Result<()> {
        let config = StoreIntegrationConfig::default();
        let store = IntegratedVectorStore::new(config, EmbeddingStrategy::TfIdf)?;

        let tx_id = store.begin_transaction(IsolationLevel::ReadCommitted)?;
        assert!(tx_id > 0);

        let vector = Vector::new(vec![1.0, 2.0, 3.0]);
        let result = store.transactional_insert(tx_id, "test_uri".to_string(), vector, None);
        assert!(result.is_ok());

        let commit_result = store.commit_transaction(tx_id);
        assert!(commit_result.is_ok());
        Ok(())
    }
}