use crate::distributed::ProcessGroup;
use anyhow::{anyhow, Result};
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use std::sync::{Arc, Mutex};
use std::time::{Duration, SystemTime, UNIX_EPOCH};
use trustformers_core::tensor::Tensor;

/// Multi-cloud training configuration and orchestration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct MultiCloudConfig {
    /// Cloud providers and their configurations
    pub providers: Vec<CloudProvider>,
    /// Cost constraints and optimization settings
    pub cost_config: CostConfig,
    /// Orchestration strategy
    pub orchestration: OrchestrationStrategy,
    /// Network topology configuration
    pub network_topology: NetworkTopology,
    /// Fault tolerance settings
    pub fault_tolerance: FaultToleranceConfig,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CloudProvider {
    /// Provider name (AWS, GCP, Azure, etc.)
    pub name: String,
    /// Available regions for this provider
    pub regions: Vec<String>,
    /// Available instance types
    pub instance_types: Vec<InstanceType>,
    /// Authentication configuration
    pub auth_config: AuthConfig,
    /// Network bandwidth between regions
    pub inter_region_bandwidth: f64, // Gbps
    /// Base latency between regions
    pub inter_region_latency: Duration,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct InstanceType {
    /// Instance type identifier
    pub name: String,
    /// Number of GPUs
    pub gpu_count: usize,
    /// GPU type
    pub gpu_type: String,
    /// Memory in GB
    pub memory_gb: usize,
    /// CPU cores
    pub cpu_cores: usize,
    /// Network bandwidth in Gbps
    pub network_bandwidth: f64,
    /// Cost per hour in USD
    pub cost_per_hour: f64,
    /// Whether spot instances are available
    pub spot_available: bool,
    /// Spot price discount (0.0 to 1.0)
    pub spot_discount: f64,
    /// Performance score (normalized)
    pub performance_score: f64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AuthConfig {
    /// Authentication type
    pub auth_type: AuthType,
    /// Configuration data (API keys, etc.)
    pub config_data: HashMap<String, String>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum AuthType {
    ApiKey,
    ServiceAccount,
    IAMRole,
    OAuth,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CostConfig {
    /// Maximum cost per hour in USD
    pub max_cost_per_hour: f64,
    /// Budget limit for the entire training session
    pub budget_limit: f64,
    /// Cost optimization strategy
    pub optimization_strategy: CostOptimizationStrategy,
    /// Whether to use spot instances
    pub use_spot_instances: bool,
    /// Maximum spot price increase tolerance
    pub spot_price_tolerance: f64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum CostOptimizationStrategy {
    /// Minimize cost regardless of performance
    MinimizeCost,
    /// Balance cost and performance
    CostPerformanceBalance,
    /// Minimize training time regardless of cost
    MinimizeTime,
    /// Custom cost function
    Custom { weight_cost: f64, weight_time: f64 },
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum OrchestrationStrategy {
    /// Single cloud provider
    SingleCloud { provider: String },
    /// Multi-cloud with manual allocation
    ManualAllocation { allocation: HashMap<String, usize> },
    /// Automatic allocation based on cost and performance
    AutoAllocation,
    /// Hybrid approach with primary and secondary clouds
    Hybrid {
        primary: String,
        secondary: Vec<String>,
    },
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct NetworkTopology {
    /// Communication pattern optimization
    pub comm_pattern: CommunicationPattern,
    /// Bandwidth requirements between nodes
    pub bandwidth_requirements: f64, // Gbps
    /// Latency tolerance
    pub latency_tolerance: Duration,
    /// Compression settings for cross-cloud communication
    pub compression: CompressionConfig,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum CommunicationPattern {
    /// All-to-all communication
    AllToAll,
    /// Ring topology
    Ring,
    /// Tree topology
    Tree,
    /// Hierarchical with regional aggregation
    Hierarchical,
    /// Adaptive based on network conditions
    Adaptive,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CompressionConfig {
    /// Whether to use compression
    pub enabled: bool,
    /// Compression algorithm
    pub algorithm: CompressionAlgorithm,
    /// Compression level (0-9)
    pub level: u8,
    /// Minimum tensor size for compression
    pub min_tensor_size: usize,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum CompressionAlgorithm {
    /// GZIP compression
    Gzip,
    /// LZ4 for fast compression
    Lz4,
    /// ZSTD for balanced compression
    Zstd,
    /// Gradient-specific compression (quantization)
    GradientQuantization,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct FaultToleranceConfig {
    /// Maximum node failures to tolerate
    pub max_failures: usize,
    /// Checkpoint frequency
    pub checkpoint_frequency: Duration,
    /// Recovery strategy
    pub recovery_strategy: RecoveryStrategy,
    /// Health check interval
    pub health_check_interval: Duration,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum RecoveryStrategy {
    /// Restart from last checkpoint
    Checkpoint,
    /// Migrate to new nodes
    Migration,
    /// Hybrid approach
    Hybrid,
}

/// Multi-cloud training orchestrator
pub struct MultiCloudOrchestrator {
    config: MultiCloudConfig,
    active_nodes: Arc<Mutex<HashMap<String, NodeInfo>>>,
    cost_tracker: Arc<Mutex<CostTracker>>,
    scheduler: Arc<Mutex<CloudScheduler>>,
}

#[derive(Debug, Clone)]
pub struct NodeInfo {
    /// Node identifier
    pub node_id: String,
    /// Cloud provider
    pub provider: String,
    /// Region
    pub region: String,
    /// Instance type
    pub instance_type: String,
    /// Whether it's a spot instance
    pub is_spot: bool,
    /// Current status
    pub status: NodeStatus,
    /// Start time
    pub start_time: SystemTime,
    /// Last health check
    pub last_health_check: SystemTime,
    /// Performance metrics
    pub performance_metrics: PerformanceMetrics,
}

#[derive(Debug, Clone)]
pub enum NodeStatus {
    Starting,
    Running,
    Stopping,
    Failed,
    Preempted, // For spot instances
}

#[derive(Debug, Clone)]
pub struct PerformanceMetrics {
    /// Throughput in samples per second
    pub throughput: f64,
    /// GPU utilization (0.0 to 1.0)
    pub gpu_utilization: f64,
    /// Memory utilization (0.0 to 1.0)
    pub memory_utilization: f64,
    /// Network utilization (0.0 to 1.0)
    pub network_utilization: f64,
    /// Communication latency
    pub comm_latency: Duration,
}

/// Cost tracking and optimization
#[derive(Debug)]
pub struct CostTracker {
    /// Total cost accumulated
    pub total_cost: f64,
    /// Cost per hour for each active node
    pub node_costs: HashMap<String, f64>,
    /// Cost history
    pub cost_history: Vec<CostEntry>,
    /// Budget alerts
    pub budget_alerts: Vec<BudgetAlert>,
}

#[derive(Debug, Clone)]
pub struct CostEntry {
    pub timestamp: SystemTime,
    pub node_id: String,
    pub cost: f64,
    pub provider: String,
}

#[derive(Debug, Clone)]
pub struct BudgetAlert {
    pub timestamp: SystemTime,
    pub alert_type: AlertType,
    pub message: String,
    pub current_cost: f64,
    pub budget_limit: f64,
}

#[derive(Debug, Clone)]
pub enum AlertType {
    BudgetWarning,  // 80% of budget
    BudgetCritical, // 95% of budget
    BudgetExceeded,
    SpotInstancePreemption,
    NodeFailure,
}

/// Cloud-aware scheduler
#[derive(Debug)]
pub struct CloudScheduler {
    /// Available resources across clouds
    pub available_resources: HashMap<String, Vec<InstanceType>>,
    /// Current resource allocation
    pub current_allocation: HashMap<String, Vec<String>>, // provider -> node_ids
    /// Scheduling algorithm
    pub algorithm: SchedulingAlgorithm,
}

#[derive(Debug, Clone)]
pub enum SchedulingAlgorithm {
    /// First fit - allocate to first available resource
    FirstFit,
    /// Best fit - optimize for cost/performance
    BestFit,
    /// Balanced - balance across providers
    Balanced,
    /// Cost optimal - minimize total cost
    CostOptimal,
    /// Performance optimal - maximize performance
    PerformanceOptimal,
}

impl MultiCloudOrchestrator {
    pub fn new(config: MultiCloudConfig) -> Self {
        Self {
            config,
            active_nodes: Arc::new(Mutex::new(HashMap::new())),
            cost_tracker: Arc::new(Mutex::new(CostTracker::new())),
            scheduler: Arc::new(Mutex::new(CloudScheduler::new())),
        }
    }

    /// Initialize multi-cloud training environment
    pub async fn initialize(&self) -> Result<()> {
        // Validate cloud provider configurations
        self.validate_providers().await?;

        // Initialize authentication with each provider
        self.initialize_auth().await?;

        // Query available resources
        self.discover_resources().await?;

        // Set up network topology
        self.setup_network_topology().await?;

        Ok(())
    }

    /// Provision training cluster across clouds
    pub async fn provision_cluster(&self, required_nodes: usize) -> Result<Vec<NodeInfo>> {
        let mut scheduler = self.scheduler.lock().unwrap();
        let allocation = scheduler.schedule_resources(required_nodes, &self.config)?;

        let mut nodes = Vec::new();
        for (provider, instance_count) in allocation {
            let provider_nodes = self.provision_nodes(&provider, instance_count).await?;
            nodes.extend(provider_nodes);
        }

        // Update active nodes
        {
            let mut active_nodes = self.active_nodes.lock().unwrap();
            for node in &nodes {
                active_nodes.insert(node.node_id.clone(), node.clone());
            }
        }

        Ok(nodes)
    }

    /// Create a multi-cloud process group for distributed training
    pub fn create_process_group(&self, nodes: &[NodeInfo]) -> Result<Arc<dyn ProcessGroup>> {
        let multi_cloud_pg =
            MultiCloudProcessGroup::new(nodes.to_vec(), self.config.network_topology.clone())?;
        Ok(Arc::new(multi_cloud_pg))
    }

    /// Monitor and optimize running training
    pub async fn monitor_training(&self) -> Result<()> {
        loop {
            // Check node health
            self.health_check().await?;

            // Update cost tracking
            self.update_costs().await?;

            // Check for budget alerts
            self.check_budget_alerts().await?;

            // Optimize resource allocation if needed
            self.optimize_allocation().await?;

            // Handle spot instance preemptions
            self.handle_preemptions().await?;

            tokio::time::sleep(self.config.fault_tolerance.health_check_interval).await;
        }
    }

    /// Handle spot instance preemption
    pub async fn handle_spot_preemption(&self, node_id: &str) -> Result<()> {
        // Mark node as preempted
        {
            let mut active_nodes = self.active_nodes.lock().unwrap();
            if let Some(node) = active_nodes.get_mut(node_id) {
                node.status = NodeStatus::Preempted;
            }
        }

        // Find replacement node
        let replacement = self.find_replacement_node(node_id).await?;

        // Migrate training state if possible
        self.migrate_training_state(node_id, &replacement.node_id).await?;

        // Update active nodes
        {
            let mut active_nodes = self.active_nodes.lock().unwrap();
            active_nodes.remove(node_id);
            active_nodes.insert(replacement.node_id.clone(), replacement);
        }

        Ok(())
    }

    // Private implementation methods

    async fn validate_providers(&self) -> Result<()> {
        // Validate each provider configuration
        for provider in &self.config.providers {
            if provider.regions.is_empty() {
                return Err(anyhow!(
                    "Provider {} has no regions configured",
                    provider.name
                ));
            }
            if provider.instance_types.is_empty() {
                return Err(anyhow!(
                    "Provider {} has no instance types configured",
                    provider.name
                ));
            }
        }
        Ok(())
    }

    async fn initialize_auth(&self) -> Result<()> {
        // Initialize authentication for each provider
        // Implementation would depend on actual cloud provider SDKs
        Ok(())
    }

    async fn discover_resources(&self) -> Result<()> {
        // Query available resources from each provider
        // Implementation would use cloud provider APIs
        Ok(())
    }

    async fn setup_network_topology(&self) -> Result<()> {
        // Configure network topology based on configuration
        // Set up VPN connections, configure firewalls, etc.
        Ok(())
    }

    async fn provision_nodes(&self, provider: &str, count: usize) -> Result<Vec<NodeInfo>> {
        // Provision nodes on the specified provider
        // Implementation would use cloud provider APIs
        let mut nodes = Vec::new();
        for i in 0..count {
            let node_id = format!(
                "{}-{}-{}",
                provider,
                SystemTime::now().duration_since(UNIX_EPOCH)?.as_secs(),
                i
            );
            let node = NodeInfo {
                node_id,
                provider: provider.to_string(),
                region: "us-west-2".to_string(), // Would be determined by scheduler
                instance_type: "p3.2xlarge".to_string(), // Would be determined by scheduler
                is_spot: self.config.cost_config.use_spot_instances,
                status: NodeStatus::Starting,
                start_time: SystemTime::now(),
                last_health_check: SystemTime::now(),
                performance_metrics: PerformanceMetrics::default(),
            };
            nodes.push(node);
        }
        Ok(nodes)
    }

    async fn health_check(&self) -> Result<()> {
        // Check health of all active nodes
        Ok(())
    }

    async fn update_costs(&self) -> Result<()> {
        // Update cost tracking for all active nodes
        let mut cost_tracker = self.cost_tracker.lock().unwrap();
        let active_nodes = self.active_nodes.lock().unwrap();

        for node in active_nodes.values() {
            let hourly_cost = self.get_node_hourly_cost(node)?;
            cost_tracker.add_cost_entry(node.node_id.clone(), hourly_cost, node.provider.clone());
        }

        Ok(())
    }

    async fn check_budget_alerts(&self) -> Result<()> {
        // Check for budget alerts and take action if needed
        let mut cost_tracker = self.cost_tracker.lock().unwrap();
        let budget_ratio = cost_tracker.total_cost / self.config.cost_config.budget_limit;

        if budget_ratio >= 1.0 {
            // Budget exceeded - stop training
            self.emergency_shutdown().await?;
        } else if budget_ratio >= 0.95 {
            // Critical budget alert
            cost_tracker.add_alert(AlertType::BudgetCritical, "Budget 95% exceeded".to_string());
        } else if budget_ratio >= 0.8 {
            // Warning alert
            cost_tracker.add_alert(AlertType::BudgetWarning, "Budget 80% used".to_string());
        }

        Ok(())
    }

    async fn optimize_allocation(&self) -> Result<()> {
        // Optimize resource allocation based on performance and cost
        Ok(())
    }

    async fn handle_preemptions(&self) -> Result<()> {
        // Handle spot instance preemptions
        Ok(())
    }

    async fn find_replacement_node(&self, _node_id: &str) -> Result<NodeInfo> {
        // Find replacement for preempted node
        Err(anyhow!("Replacement node finding not implemented"))
    }

    async fn migrate_training_state(&self, _from_node: &str, _to_node: &str) -> Result<()> {
        // Migrate training state between nodes
        Ok(())
    }

    async fn emergency_shutdown(&self) -> Result<()> {
        // Emergency shutdown due to budget exceeded
        Ok(())
    }

    fn get_node_hourly_cost(&self, node: &NodeInfo) -> Result<f64> {
        // Calculate hourly cost for a node
        for provider in &self.config.providers {
            if provider.name == node.provider {
                for instance_type in &provider.instance_types {
                    if instance_type.name == node.instance_type {
                        let base_cost = instance_type.cost_per_hour;
                        if node.is_spot {
                            return Ok(base_cost * (1.0 - instance_type.spot_discount));
                        } else {
                            return Ok(base_cost);
                        }
                    }
                }
            }
        }
        Err(anyhow!("Instance type not found"))
    }
}

/// Multi-cloud process group implementation
pub struct MultiCloudProcessGroup {
    #[allow(dead_code)]
    nodes: Vec<NodeInfo>,
    topology: NetworkTopology,
    rank: usize,
    world_size: usize,
}

impl MultiCloudProcessGroup {
    pub fn new(nodes: Vec<NodeInfo>, topology: NetworkTopology) -> Result<Self> {
        let world_size = nodes.len();
        Ok(Self {
            nodes,
            topology,
            rank: 0, // Would be determined based on node assignment
            world_size,
        })
    }
}

impl ProcessGroup for MultiCloudProcessGroup {
    fn all_reduce(&self, tensors: &mut [Tensor]) -> Result<()> {
        // Implement multi-cloud all-reduce with compression and topology optimization
        match self.topology.comm_pattern {
            CommunicationPattern::Ring => self.ring_all_reduce(tensors),
            CommunicationPattern::Tree => self.tree_all_reduce(tensors),
            CommunicationPattern::Hierarchical => self.hierarchical_all_reduce(tensors),
            _ => self.simple_all_reduce(tensors),
        }
    }

    fn broadcast(&self, tensor: &mut Tensor, src_rank: usize) -> Result<()> {
        // Implement multi-cloud broadcast
        if self.rank == src_rank {
            // Broadcast from this rank
            self.send_to_all(tensor)
        } else {
            // Receive from source rank
            self.receive_from(tensor, src_rank)
        }
    }

    fn reduce(&self, tensor: &mut Tensor, dst_rank: usize) -> Result<()> {
        // Implement multi-cloud reduce
        if self.rank == dst_rank {
            // Receive and accumulate from all ranks
            self.receive_and_accumulate(tensor)
        } else {
            // Send to destination rank
            self.send_to(tensor, dst_rank)
        }
    }

    fn barrier(&self) -> Result<()> {
        // Implement multi-cloud barrier synchronization
        Ok(())
    }

    fn rank(&self) -> usize {
        self.rank
    }

    fn world_size(&self) -> usize {
        self.world_size
    }
}

impl MultiCloudProcessGroup {
    fn ring_all_reduce(&self, _tensors: &mut [Tensor]) -> Result<()> {
        // Ring-based all-reduce for cross-cloud communication
        Ok(())
    }

    fn tree_all_reduce(&self, _tensors: &mut [Tensor]) -> Result<()> {
        // Tree-based all-reduce for cross-cloud communication
        Ok(())
    }

    fn hierarchical_all_reduce(&self, _tensors: &mut [Tensor]) -> Result<()> {
        // Hierarchical all-reduce with regional aggregation
        Ok(())
    }

    fn simple_all_reduce(&self, _tensors: &mut [Tensor]) -> Result<()> {
        // Simple all-reduce implementation
        Ok(())
    }

    fn send_to_all(&self, _tensor: &Tensor) -> Result<()> {
        // Send tensor to all other ranks
        Ok(())
    }

    fn receive_from(&self, _tensor: &mut Tensor, _src_rank: usize) -> Result<()> {
        // Receive tensor from source rank
        Ok(())
    }

    fn send_to(&self, _tensor: &Tensor, _dst_rank: usize) -> Result<()> {
        // Send tensor to destination rank
        Ok(())
    }

    fn receive_and_accumulate(&self, _tensor: &mut Tensor) -> Result<()> {
        // Receive and accumulate tensors from all ranks
        Ok(())
    }
}

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

impl CostTracker {
    pub fn new() -> Self {
        Self {
            total_cost: 0.0,
            node_costs: HashMap::new(),
            cost_history: Vec::new(),
            budget_alerts: Vec::new(),
        }
    }

    pub fn add_cost_entry(&mut self, node_id: String, cost: f64, provider: String) {
        let entry = CostEntry {
            timestamp: SystemTime::now(),
            node_id: node_id.clone(),
            cost,
            provider,
        };

        self.cost_history.push(entry);
        self.total_cost += cost;
        *self.node_costs.entry(node_id).or_insert(0.0) += cost;
    }

    pub fn add_alert(&mut self, alert_type: AlertType, message: String) {
        let alert = BudgetAlert {
            timestamp: SystemTime::now(),
            alert_type,
            message,
            current_cost: self.total_cost,
            budget_limit: 0.0, // Would be set from config
        };
        self.budget_alerts.push(alert);
    }
}

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

impl CloudScheduler {
    pub fn new() -> Self {
        Self {
            available_resources: HashMap::new(),
            current_allocation: HashMap::new(),
            algorithm: SchedulingAlgorithm::BestFit,
        }
    }

    pub fn schedule_resources(
        &mut self,
        required_nodes: usize,
        config: &MultiCloudConfig,
    ) -> Result<HashMap<String, usize>> {
        match &config.orchestration {
            OrchestrationStrategy::SingleCloud { provider } => {
                Ok([(provider.clone(), required_nodes)].into_iter().collect())
            },
            OrchestrationStrategy::ManualAllocation { allocation } => Ok(allocation.clone()),
            OrchestrationStrategy::AutoAllocation => self.auto_schedule(required_nodes, config),
            OrchestrationStrategy::Hybrid {
                primary,
                secondary: _,
            } => {
                // Prefer primary, fallback to secondary
                Ok([(primary.clone(), required_nodes)].into_iter().collect())
            },
        }
    }

    fn auto_schedule(
        &self,
        required_nodes: usize,
        config: &MultiCloudConfig,
    ) -> Result<HashMap<String, usize>> {
        // Implement automatic scheduling based on cost and performance
        let mut allocation = HashMap::new();

        // Simple round-robin allocation for now
        let provider_count = config.providers.len();
        let nodes_per_provider = required_nodes / provider_count;
        let remainder = required_nodes % provider_count;

        for (i, provider) in config.providers.iter().enumerate() {
            let nodes = nodes_per_provider + if i < remainder { 1 } else { 0 };
            if nodes > 0 {
                allocation.insert(provider.name.clone(), nodes);
            }
        }

        Ok(allocation)
    }
}

impl Default for PerformanceMetrics {
    fn default() -> Self {
        Self {
            throughput: 0.0,
            gpu_utilization: 0.0,
            memory_utilization: 0.0,
            network_utilization: 0.0,
            comm_latency: Duration::from_millis(0),
        }
    }
}

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

    #[test]
    fn test_multicloud_config_creation() {
        let config = create_test_config();
        assert_eq!(config.providers.len(), 2);
        assert!(config.cost_config.max_cost_per_hour > 0.0);
    }

    #[test]
    fn test_cost_tracker() {
        let mut tracker = CostTracker::new();
        tracker.add_cost_entry("node1".to_string(), 5.0, "aws".to_string());
        assert_eq!(tracker.total_cost, 5.0);
        assert_eq!(tracker.cost_history.len(), 1);
    }

    #[test]
    fn test_cloud_scheduler() {
        let config = create_test_config();
        let mut scheduler = CloudScheduler::new();
        let allocation = scheduler.schedule_resources(4, &config).unwrap();
        assert!(allocation.values().sum::<usize>() == 4);
    }

    fn create_test_config() -> MultiCloudConfig {
        MultiCloudConfig {
            providers: vec![
                CloudProvider {
                    name: "aws".to_string(),
                    regions: vec!["us-west-2".to_string()],
                    instance_types: vec![InstanceType {
                        name: "p3.2xlarge".to_string(),
                        gpu_count: 1,
                        gpu_type: "V100".to_string(),
                        memory_gb: 64,
                        cpu_cores: 8,
                        network_bandwidth: 10.0,
                        cost_per_hour: 3.06,
                        spot_available: true,
                        spot_discount: 0.7,
                        performance_score: 0.9,
                    }],
                    auth_config: AuthConfig {
                        auth_type: AuthType::IAMRole,
                        config_data: HashMap::new(),
                    },
                    inter_region_bandwidth: 25.0,
                    inter_region_latency: Duration::from_millis(50),
                },
                CloudProvider {
                    name: "gcp".to_string(),
                    regions: vec!["us-west1".to_string()],
                    instance_types: vec![InstanceType {
                        name: "n1-standard-8".to_string(),
                        gpu_count: 1,
                        gpu_type: "T4".to_string(),
                        memory_gb: 32,
                        cpu_cores: 8,
                        network_bandwidth: 16.0,
                        cost_per_hour: 2.5,
                        spot_available: true,
                        spot_discount: 0.6,
                        performance_score: 0.7,
                    }],
                    auth_config: AuthConfig {
                        auth_type: AuthType::ServiceAccount,
                        config_data: HashMap::new(),
                    },
                    inter_region_bandwidth: 20.0,
                    inter_region_latency: Duration::from_millis(60),
                },
            ],
            cost_config: CostConfig {
                max_cost_per_hour: 100.0,
                budget_limit: 1000.0,
                optimization_strategy: CostOptimizationStrategy::CostPerformanceBalance,
                use_spot_instances: true,
                spot_price_tolerance: 0.2,
            },
            orchestration: OrchestrationStrategy::AutoAllocation,
            network_topology: NetworkTopology {
                comm_pattern: CommunicationPattern::Hierarchical,
                bandwidth_requirements: 10.0,
                latency_tolerance: Duration::from_millis(100),
                compression: CompressionConfig {
                    enabled: true,
                    algorithm: CompressionAlgorithm::GradientQuantization,
                    level: 6,
                    min_tensor_size: 1024,
                },
            },
            fault_tolerance: FaultToleranceConfig {
                max_failures: 2,
                checkpoint_frequency: Duration::from_secs(300),
                recovery_strategy: RecoveryStrategy::Hybrid,
                health_check_interval: Duration::from_secs(30),
            },
        }
    }
}
