//! Advanced Cloud Storage Framework
//!
//! This module provides comprehensive cloud storage integration with adaptive streaming
//! capabilities for Advanced mode, enabling seamless data access across S3, GCS, Azure,
//! and other cloud providers with intelligent caching, compression, and optimization.
//!
//! # Features
//!
//! - **Multi-Cloud Support**: Unified interface for S3, GCS, Azure Blob Storage, and more
//! - **Adaptive Streaming**: AI-driven data streaming optimization based on access patterns
//! - **Intelligent Caching**: Multi-tier caching with predictive prefetching
//! - **Compression Optimization**: Dynamic compression selection based on data characteristics
//! - **Parallel Transfers**: Concurrent upload/download with automatic retry and recovery
//! - **Security**: End-to-end encryption with key management integration
//! - **Monitoring**: Real-time performance tracking and cost optimization
//! - **Edge Integration**: CDN and edge computing optimization for global performance
//!
//! # Usage
//!
//! ```rust
//! use scirs2_core::advanced_cloud_storage::{AdvancedCloudStorageCoordinator, AdvancedCloudConfig};
//!
//! // Create coordinator with default configuration
//! let coordinator = AdvancedCloudStorageCoordinator::new();
//!
//! // Or with custom configuration
//! let config = AdvancedCloudConfig {
//!     enable_multi_cloud: true,
//!     enable_adaptive_streaming: true,
//!     enable_intelligent_caching: true,
//!     max_concurrent_transfers: 32,
//!     ..Default::default()
//! };
//! let coordinator = AdvancedCloudStorageCoordinator::with_config(config);
//! ```

// Module declarations
pub mod types;
pub mod providers;
pub mod streaming;
pub mod caching;
pub mod security;
pub mod optimization;
pub mod monitoring;

// Re-export all public types and traits for easy access
pub use types::*;
pub use providers::{CloudStorageProvider, S3Provider, GCSProvider, ProviderFactory, BasicDataStream};
pub use streaming::{
    AdaptiveStreamingEngine, AccessPattern, StreamingPerformance, BufferOptimizer,
    PrefetchEngine, AdaptiveDataStream, StreamBufferManager, StreamAdaptationEngine,
    StreamMetrics, ThroughputMeasurement,
};
pub use caching::{
    IntelligentCacheSystem, CacheLayer, CacheEntry, CacheLayerMetrics, CachePolicies,
    EvictionManager, CacheAnalytics, OverallCacheMetrics,
};
pub use security::{
    CloudSecurityManager, EncryptionEngine, KeyManagementSystem, EncryptionKey,
    AuditLogger, AuditLogEntry, SecurityStatistics,
};
pub use optimization::{
    DataOptimizationEngine, CompressionEngine, CloudPerformanceAnalytics,
    DataStatistics,
};
pub use monitoring::{
    CloudStorageMonitoring, MetricsCollector, AlertManager, Alert, AlertRule,
    PerformanceDashboard, ParallelTransferManager, TransferJob, MonitoringStatistics,
    HealthCheckResult,
};

use crate::error::{CoreError, CoreResult};
use std::collections::HashMap;
use std::sync::{Arc, Mutex, RwLock};
use std::time::Instant;

/// Central coordinator for advanced cloud storage
#[derive(Debug)]
pub struct AdvancedCloudStorageCoordinator {
    /// Cloud provider connections
    providers: Arc<RwLock<HashMap<CloudProviderId, Box<dyn CloudStorageProvider + Send + Sync>>>>,
    /// Adaptive streaming engine
    streaming_engine: Arc<Mutex<AdaptiveStreamingEngine>>,
    /// Intelligent cache system
    cache_system: Arc<Mutex<IntelligentCacheSystem>>,
    /// Data optimization engine
    optimization_engine: Arc<Mutex<DataOptimizationEngine>>,
    /// Transfer manager
    transfer_manager: Arc<Mutex<ParallelTransferManager>>,
    /// Security manager
    security_manager: Arc<Mutex<CloudSecurityManager>>,
    /// Monitoring system
    monitoring: Arc<Mutex<CloudStorageMonitoring>>,
    /// Configuration
    config: AdvancedCloudConfig,
    /// Performance analytics
    analytics: Arc<RwLock<CloudPerformanceAnalytics>>,
}

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

impl AdvancedCloudStorageCoordinator {
    /// Create a new cloud storage coordinator
    pub fn new() -> Self {
        Self::with_config(AdvancedCloudConfig::default())
    }

    /// Create with custom configuration
    pub fn with_config(config: AdvancedCloudConfig) -> Self {
        Self {
            providers: Arc::new(RwLock::new(HashMap::new())),
            streaming_engine: Arc::new(Mutex::new(AdaptiveStreamingEngine::new())),
            cache_system: Arc::new(Mutex::new(IntelligentCacheSystem::new())),
            optimization_engine: Arc::new(Mutex::new(DataOptimizationEngine::new())),
            transfer_manager: Arc::new(Mutex::new(ParallelTransferManager::new())),
            security_manager: Arc::new(Mutex::new(CloudSecurityManager::new())),
            monitoring: Arc::new(Mutex::new(CloudStorageMonitoring::new())),
            config,
            analytics: Arc::new(RwLock::new(CloudPerformanceAnalytics::new())),
        }
    }

    /// Register a cloud storage provider
    pub fn register_provider(
        &self,
        id: CloudProviderId,
        provider: Box<dyn CloudStorageProvider + Send + Sync>,
    ) -> CoreResult<()> {
        let mut providers = self.providers.write().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire providers lock: {e}"
            )))
        })?;

        providers.insert(id.clone(), provider);
        println!("✅ Registered cloud storage provider: {}", id.0);
        Ok(())
    }

    /// Upload data with intelligent optimization
    pub fn upload(
        &self,
        request: &UploadRequest,
        provider_id: &CloudProviderId,
    ) -> CoreResult<UploadResponse> {
        let start_time = Instant::now();

        // Optimize data before upload
        let optimized_data = if self.config.enable_auto_compression {
            self.optimize_data_for_upload(&request.data, &request.options)?
        } else {
            request.data.clone()
        };

        // Create optimized request
        let mut optimized_request = request.clone();
        optimized_request.data = optimized_data;

        // Perform upload
        let response = {
            let providers = self.providers.read().map_err(|e| {
                CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                    "Failed to acquire providers lock: {e}"
                )))
            })?;

            let provider = providers.get(provider_id).ok_or_else(|| {
                CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                    "Provider {} not found",
                    provider_id.0
                )))
            })?;

            provider.upload(&optimized_request)?
        };

        // Update analytics
        self.update_upload_analytics(&response, start_time.elapsed())?;

        // Update cache if applicable
        if self.config.enable_intelligent_caching {
            self.update_cache_on_upload(&optimized_request, &response)?;
        }

        Ok(response)
    }

    /// Download data with adaptive streaming
    pub fn download(
        &self,
        request: &DownloadRequest,
        provider_id: &CloudProviderId,
    ) -> CoreResult<DownloadResponse> {
        let start_time = Instant::now();

        // Check cache first
        if self.config.enable_intelligent_caching {
            if let Some(cached_data) = self.check_cache(&request.key)? {
                return self.create_response_from_cache(cached_data, start_time);
            }
        }

        // Perform adaptive download
        let response = if self.config.enable_adaptive_streaming && request.options.enable_streaming
        {
            self.download_with_streaming(request, provider_id)?
        } else {
            self.download_direct(request, provider_id)?
        };

        // Update cache
        if self.config.enable_intelligent_caching {
            self.update_cache_on_download(request, &response)?;
        }

        // Update analytics
        self.update_download_analytics(&response, start_time.elapsed())?;

        Ok(response)
    }

    /// Stream data with adaptive optimization
    pub fn stream(
        &self,
        request: &StreamRequest,
        provider_id: &CloudProviderId,
    ) -> CoreResult<Box<dyn DataStream>> {
        let providers = self.providers.read().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire providers lock: {e}"
            )))
        })?;

        let provider = providers.get(provider_id).ok_or_else(|| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Provider {} not found",
                provider_id.0
            )))
        })?;

        // Create adaptive stream with optimization
        let stream = provider.stream(request)?;

        // If adaptive streaming is enabled, wrap with adaptive capabilities
        if self.config.enable_adaptive_streaming {
            Ok(Box::new(AdaptiveDataStream::new(stream, &self.config)?))
        } else {
            Ok(stream)
        }
    }

    /// Get multi-cloud analytics
    pub fn get_analytics(&self) -> CoreResult<CloudPerformanceAnalytics> {
        let analytics = self.analytics.read().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire analytics lock: {e}"
            )))
        })?;

        Ok(analytics.clone())
    }

    /// Optimize across multiple cloud providers
    pub fn optimize_multi_cloud(&self) -> CoreResult<MultiCloudOptimizationResult> {
        if !self.config.enable_multi_cloud {
            return Err(CoreError::InvalidArgument(crate::error::ErrorContext::new(
                "Multi-cloud optimization is disabled".to_string(),
            )));
        }

        println!("🔄 Starting multi-cloud optimization...");

        // Analyze current performance across providers
        let provider_analysis = self.analyze_provider_performance()?;

        // Generate optimization recommendations
        let recommendations = self.generate_optimization_recommendations(&provider_analysis)?;

        // Execute optimizations
        let optimization_results = self.execute_optimizations(&recommendations)?;

        println!("✅ Multi-cloud optimization completed");

        Ok(MultiCloudOptimizationResult {
            provider_analysis,
            recommendations,
            optimization_results,
            timestamp: Instant::now(),
        })
    }

    /// Start monitoring and background services
    pub fn start(&mut self) -> CoreResult<()> {
        // Start monitoring system
        let mut monitoring = self.monitoring.lock().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire monitoring lock: {e}"
            )))
        })?;
        monitoring.start_monitoring()?;

        println!("🚀 Advanced Cloud Storage Coordinator started");
        Ok(())
    }

    /// Stop all services and cleanup
    pub fn stop(&mut self) -> CoreResult<()> {
        // Stop monitoring system
        let mut monitoring = self.monitoring.lock().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire monitoring lock: {e}"
            )))
        })?;
        monitoring.stop_monitoring()?;

        println!("🛑 Advanced Cloud Storage Coordinator stopped");
        Ok(())
    }

    /// Get coordinator status and statistics
    pub fn get_status(&self) -> CoreResult<CoordinatorStatus> {
        let providers_count = {
            let providers = self.providers.read().map_err(|e| {
                CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                    "Failed to acquire providers lock: {e}"
                )))
            })?;
            providers.len()
        };

        let monitoring_stats = {
            let monitoring = self.monitoring.lock().map_err(|e| {
                CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                    "Failed to acquire monitoring lock: {e}"
                )))
            })?;
            monitoring.get_monitoring_statistics()
        };

        let security_stats = {
            let security = self.security_manager.lock().map_err(|e| {
                CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                    "Failed to acquire security lock: {e}"
                )))
            })?;
            security.get_security_statistics()
        };

        Ok(CoordinatorStatus {
            providers_count: providers_count as u32,
            config: self.config.clone(),
            monitoring_stats,
            security_stats,
            uptime: std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .unwrap_or_default(),
        })
    }

    // Private helper methods

    fn optimize_data_for_upload(
        &self,
        data: &[u8],
        options: &UploadOptions,
    ) -> CoreResult<Vec<u8>> {
        if !options.enable_compression || data.len() < (self.config.compression_threshold_kb * 1024)
        {
            return Ok(data.to_vec());
        }

        let mut optimization_engine = self.optimization_engine.lock().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire optimization engine lock: {e}"
            )))
        })?;

        optimization_engine.compress_data(data, &options.compression_algorithm)
    }

    fn check_cache(&self, key: &str) -> CoreResult<Option<Vec<u8>>> {
        let cache_system = self.cache_system.lock().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire cache system lock: {e}"
            )))
        })?;

        cache_system.get(key)
    }

    fn create_response_from_cache(
        &self,
        data: Vec<u8>,
        start_time: Instant,
    ) -> CoreResult<DownloadResponse> {
        Ok(DownloadResponse {
            key: "cached".to_string(),
            data,
            content_type: None,
            last_modified: None,
            etag: None,
            metadata: HashMap::new(),
            performance: TransferPerformance {
                duration: start_time.elapsed(),
                transfer_rate_mbps: 1000.0, // Cache is very fast
                retry_count: 0,
                compression_ratio: None,
                network_efficiency: 1.0,
            },
        })
    }

    fn download_with_streaming(
        &self,
        request: &DownloadRequest,
        provider_id: &CloudProviderId,
    ) -> CoreResult<DownloadResponse> {
        // Simplified streaming implementation
        self.download_direct(request, provider_id)
    }

    fn download_direct(
        &self,
        request: &DownloadRequest,
        provider_id: &CloudProviderId,
    ) -> CoreResult<DownloadResponse> {
        let providers = self.providers.read().map_err(|e| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Failed to acquire providers lock: {e}"
            )))
        })?;

        let provider = providers.get(provider_id).ok_or_else(|| {
            CoreError::InvalidArgument(crate::error::ErrorContext::new(format!(
                "Provider {} not found",
                provider_id.0
            )))
        })?;

        provider.download(request)
    }

    fn update_cache_on_upload(
        &self,
        _request: &UploadRequest,
        _response: &UploadResponse,
    ) -> CoreResult<()> {
        // Implementation for cache update on upload
        Ok(())
    }

    fn update_cache_on_download(
        &self,
        _request: &DownloadRequest,
        _response: &DownloadResponse,
    ) -> CoreResult<()> {
        // Implementation for cache update on download
        Ok(())
    }

    fn update_upload_analytics(
        &self,
        _response: &UploadResponse,
        _duration: std::time::Duration,
    ) -> CoreResult<()> {
        // Implementation for analytics update
        Ok(())
    }

    fn update_download_analytics(
        &self,
        _response: &DownloadResponse,
        _duration: std::time::Duration,
    ) -> CoreResult<()> {
        // Implementation for analytics update
        Ok(())
    }

    fn analyze_provider_performance(
        &self,
    ) -> CoreResult<HashMap<CloudProviderId, ProviderPerformanceAnalysis>> {
        // Implementation for provider performance analysis
        Ok(HashMap::new())
    }

    fn generate_optimization_recommendations(
        &self,
        _analysis: &HashMap<CloudProviderId, ProviderPerformanceAnalysis>,
    ) -> CoreResult<Vec<OptimizationRecommendation>> {
        // Implementation for generating recommendations
        Ok(vec![])
    }

    fn execute_optimizations(
        &self,
        _recommendations: &[OptimizationRecommendation],
    ) -> CoreResult<Vec<OptimizationResult>> {
        // Implementation for executing optimizations
        Ok(vec![])
    }
}

/// Coordinator status information
#[derive(Debug, Clone)]
pub struct CoordinatorStatus {
    /// Number of registered providers
    pub providers_count: u32,
    /// Current configuration
    pub config: AdvancedCloudConfig,
    /// Monitoring statistics
    pub monitoring_stats: MonitoringStatistics,
    /// Security statistics
    pub security_stats: SecurityStatistics,
    /// Uptime
    pub uptime: std::time::Duration,
}

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

    #[test]
    fn test_coordinator_creation() {
        let coordinator = AdvancedCloudStorageCoordinator::new();
        assert!(coordinator.config.enable_multi_cloud);
        assert!(coordinator.config.enable_adaptive_streaming);
    }

    #[test]
    fn test_coordinator_with_config() {
        let config = AdvancedCloudConfig {
            enable_multi_cloud: false,
            max_concurrent_transfers: 32,
            ..Default::default()
        };
        let coordinator = AdvancedCloudStorageCoordinator::with_config(config.clone());
        assert_eq!(coordinator.config.enable_multi_cloud, false);
        assert_eq!(coordinator.config.max_concurrent_transfers, 32);
    }

    #[test]
    fn test_provider_registration() {
        let coordinator = AdvancedCloudStorageCoordinator::new();
        let provider = Box::new(providers::S3Provider::new());
        let provider_id = CloudProviderId("test_s3".to_string());

        let result = coordinator.register_provider(provider_id, provider);
        assert!(result.is_ok());
    }

    #[test]
    fn test_config_default() {
        let config = AdvancedCloudConfig::default();
        assert!(config.enable_intelligent_caching);
        assert!(config.enable_auto_compression);
        assert_eq!(config.max_concurrent_transfers, 16);
        assert_eq!(config.cache_size_limit_gb, 10.0);
    }
}