voirs-cli 0.1.0-rc.1

// Distributed processing capabilities for VoiRS cloud integration
use anyhow::Result;
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use std::sync::Arc;
use tokio::sync::{RwLock, Semaphore};
use voirs_sdk::types::SynthesisConfig;

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CloudNode {
    pub id: String,
    pub endpoint: String,
    pub capacity: u32,
    pub current_load: u32,
    pub capabilities: Vec<String>,
    pub region: String,
    pub latency_ms: u32,
    pub availability: f32,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DistributedTask {
    pub id: String,
    pub task_type: TaskType,
    pub priority: TaskPriority,
    pub input_data: TaskInput,
    pub config: SynthesisConfig,
    pub target_nodes: Option<Vec<String>>,
    pub timeout_ms: u32,
    pub retry_count: u32,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum TaskType {
    Synthesis,
    VoiceCloning,
    BatchProcessing,
    AudioProcessing,
    QualityAnalysis,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum TaskPriority {
    Low,
    Normal,
    High,
    Critical,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TaskInput {
    pub text: Option<String>,
    pub audio_data: Option<Vec<u8>>,
    pub metadata: HashMap<String, String>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TaskResult {
    pub task_id: String,
    pub node_id: String,
    pub success: bool,
    pub result_data: Option<Vec<u8>>,
    pub error_message: Option<String>,
    pub processing_time_ms: u32,
    pub quality_metrics: Option<QualityMetrics>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct QualityMetrics {
    pub mcd: f32,
    pub pesq: f32,
    pub stoi: f32,
    pub naturalness_score: f32,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct LoadBalancingStrategy {
    pub strategy_type: LoadBalancingType,
    pub weight_factors: WeightFactors,
    pub failover_enabled: bool,
    pub health_check_interval_ms: u32,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum LoadBalancingType {
    RoundRobin,
    LeastConnections,
    WeightedRoundRobin,
    LatencyBased,
    CapacityBased,
    Adaptive,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct WeightFactors {
    pub latency_weight: f32,
    pub capacity_weight: f32,
    pub availability_weight: f32,
    pub quality_weight: f32,
}

#[derive(Clone)]
pub struct DistributedProcessingManager {
    nodes: Arc<RwLock<HashMap<String, CloudNode>>>,
    active_tasks: Arc<RwLock<HashMap<String, DistributedTask>>>,
    completed_tasks: Arc<RwLock<HashMap<String, TaskResult>>>,
    load_balancer: LoadBalancer,
    task_queue: Arc<RwLock<Vec<DistributedTask>>>,
    concurrency_limiter: Arc<Semaphore>,
    config: DistributedConfig,
}

#[derive(Debug, Clone)]
pub struct DistributedConfig {
    pub max_concurrent_tasks: u32,
    pub default_timeout_ms: u32,
    pub max_retry_attempts: u32,
    pub health_check_interval_ms: u32,
    pub node_selection_strategy: LoadBalancingStrategy,
}

#[derive(Clone)]
pub struct LoadBalancer {
    strategy: LoadBalancingStrategy,
    node_scores: Arc<RwLock<HashMap<String, f32>>>,
    round_robin_counter: Arc<std::sync::atomic::AtomicUsize>,
}

impl DistributedProcessingManager {
    pub fn new(config: DistributedConfig) -> Self {
        let concurrency_limiter = Arc::new(Semaphore::new(config.max_concurrent_tasks as usize));

        Self {
            nodes: Arc::new(RwLock::new(HashMap::new())),
            active_tasks: Arc::new(RwLock::new(HashMap::new())),
            completed_tasks: Arc::new(RwLock::new(HashMap::new())),
            load_balancer: LoadBalancer::new(config.node_selection_strategy.clone()),
            task_queue: Arc::new(RwLock::new(Vec::new())),
            concurrency_limiter,
            config,
        }
    }

    /// Register a new cloud node for distributed processing
    pub async fn register_node(&self, node: CloudNode) -> Result<()> {
        let mut nodes = self.nodes.write().await;
        nodes.insert(node.id.clone(), node);
        Ok(())
    }

    /// Submit a task for distributed processing
    pub async fn submit_task(&self, task: DistributedTask) -> Result<String> {
        let task_id = task.id.clone();

        // Add to active tasks
        {
            let mut active_tasks = self.active_tasks.write().await;
            active_tasks.insert(task_id.clone(), task.clone());
        }

        // Select optimal node for task
        let selected_node = self.select_optimal_node(&task).await?;

        // Execute task on selected node
        let task_executor = self.clone();
        let task_id_for_spawn = task_id.clone();
        tokio::spawn(async move {
            // Execute the task on the selected node
            let result = task_executor
                .execute_task_on_node(&task, &selected_node)
                .await;

            // Update task status and store result
            task_executor
                .update_task_status(&task_id_for_spawn, result)
                .await;
        });

        Ok(task_id)
    }

    /// Select the optimal node for a given task
    async fn select_optimal_node(&self, task: &DistributedTask) -> Result<CloudNode> {
        let nodes = self.nodes.read().await;

        if nodes.is_empty() {
            return Err(anyhow::anyhow!("No cloud nodes available"));
        }

        // If specific nodes are targeted, filter to those
        let candidate_nodes: Vec<&CloudNode> = if let Some(target_nodes) = &task.target_nodes {
            nodes
                .values()
                .filter(|node| target_nodes.contains(&node.id))
                .collect()
        } else {
            nodes.values().collect()
        };

        if candidate_nodes.is_empty() {
            return Err(anyhow::anyhow!("No suitable nodes found for task"));
        }

        // Use load balancer to select optimal node
        let optimal_node = self
            .load_balancer
            .select_node(&candidate_nodes, task)
            .await?;
        Ok(optimal_node.clone())
    }

    /// Monitor task progress and handle completion
    pub async fn monitor_task(&self, task_id: &str) -> Result<TaskResult> {
        // Check if task is still active
        {
            let active_tasks = self.active_tasks.read().await;
            if let Some(task) = active_tasks.get(task_id) {
                // Task is still running, check its status
                let status = self
                    .get_task_status_from_node(task_id, &task.config)
                    .await?;
                if !status.is_complete {
                    // Task is still in progress, return progress info
                    return Ok(TaskResult {
                        task_id: task_id.to_string(),
                        node_id: status.node_id,
                        success: false,
                        result_data: None,
                        error_message: Some("Task in progress".to_string()),
                        processing_time_ms: status.elapsed_ms,
                        quality_metrics: None,
                    });
                }
            }
        }

        // Check completed tasks
        {
            let completed_tasks = self.completed_tasks.read().await;
            if let Some(result) = completed_tasks.get(task_id) {
                return Ok(result.clone());
            }
        }

        // Task not found
        Err(anyhow::anyhow!("Task {} not found", task_id))
    }

    /// Get cluster health status
    pub async fn get_cluster_health(&self) -> Result<ClusterHealth> {
        let nodes = self.nodes.read().await;
        let total_nodes = nodes.len();
        let healthy_nodes = nodes
            .values()
            .filter(|node| node.availability > 0.9)
            .count();

        let active_tasks = self.active_tasks.read().await;
        let total_capacity: u32 = nodes.values().map(|node| node.capacity).sum();
        let current_load: u32 = nodes.values().map(|node| node.current_load).sum();

        Ok(ClusterHealth {
            total_nodes,
            healthy_nodes,
            total_capacity,
            current_load,
            utilization_percentage: if total_capacity > 0 {
                (current_load as f32 / total_capacity as f32) * 100.0
            } else {
                0.0
            },
            active_tasks: active_tasks.len(),
            average_latency_ms: self.calculate_average_latency().await,
        })
    }

    async fn calculate_average_latency(&self) -> f32 {
        let nodes = self.nodes.read().await;
        if nodes.is_empty() {
            return 0.0;
        }

        let total_latency: u32 = nodes.values().map(|node| node.latency_ms).sum();
        total_latency as f32 / nodes.len() as f32
    }

    /// Execute a task on a specific node
    async fn execute_task_on_node(
        &self,
        task: &DistributedTask,
        node: &CloudNode,
    ) -> Result<TaskResult> {
        tracing::info!("Executing task {} on node {}", task.id, node.id);

        let start_time = std::time::Instant::now();

        // Simulate task execution based on task type
        let result = match task.task_type {
            TaskType::Synthesis => self.execute_synthesis_task(task, node).await,
            TaskType::VoiceCloning => self.execute_voice_cloning_task(task, node).await,
            TaskType::BatchProcessing => self.execute_batch_processing_task(task, node).await,
            TaskType::AudioProcessing => self.execute_audio_processing_task(task, node).await,
            TaskType::QualityAnalysis => self.execute_quality_analysis_task(task, node).await,
        };

        let processing_time = start_time.elapsed().as_millis() as u32;

        match result {
            Ok(result_data) => {
                // Calculate quality metrics if applicable
                let quality_metrics = self
                    .calculate_quality_metrics(&result_data, &task.task_type)
                    .await;

                Ok(TaskResult {
                    task_id: task.id.clone(),
                    node_id: node.id.clone(),
                    success: true,
                    result_data: Some(result_data),
                    error_message: None,
                    processing_time_ms: processing_time,
                    quality_metrics,
                })
            }
            Err(e) => {
                tracing::error!("Task {} failed on node {}: {}", task.id, node.id, e);
                Ok(TaskResult {
                    task_id: task.id.clone(),
                    node_id: node.id.clone(),
                    success: false,
                    result_data: None,
                    error_message: Some(e.to_string()),
                    processing_time_ms: processing_time,
                    quality_metrics: None,
                })
            }
        }
    }

    /// Execute synthesis task
    async fn execute_synthesis_task(
        &self,
        task: &DistributedTask,
        node: &CloudNode,
    ) -> Result<Vec<u8>> {
        if let Some(text) = &task.input_data.text {
            tracing::debug!("Synthesizing text: '{}' on node {}", text, node.id);

            // Simulate text-to-speech synthesis
            let synthesis_delay = std::cmp::min(text.len() * 10, 5000); // Max 5 seconds
            tokio::time::sleep(tokio::time::Duration::from_millis(synthesis_delay as u64)).await;

            // Generate synthetic audio data
            let audio_data = self.generate_synthetic_audio(text, &task.config).await?;

            Ok(audio_data)
        } else {
            Err(anyhow::anyhow!("No text provided for synthesis task"))
        }
    }

    /// Execute voice cloning task
    async fn execute_voice_cloning_task(
        &self,
        task: &DistributedTask,
        node: &CloudNode,
    ) -> Result<Vec<u8>> {
        if let Some(audio_data) = &task.input_data.audio_data {
            tracing::debug!(
                "Voice cloning with {} bytes of audio data on node {}",
                audio_data.len(),
                node.id
            );

            // Simulate voice cloning processing
            let cloning_delay = std::cmp::min(audio_data.len() / 1000, 10000); // Max 10 seconds
            tokio::time::sleep(tokio::time::Duration::from_millis(cloning_delay as u64)).await;

            // Generate cloned voice model
            let cloned_model = self.generate_cloned_voice_model(audio_data).await?;

            Ok(cloned_model)
        } else {
            Err(anyhow::anyhow!(
                "No audio data provided for voice cloning task"
            ))
        }
    }

    /// Execute batch processing task
    async fn execute_batch_processing_task(
        &self,
        task: &DistributedTask,
        node: &CloudNode,
    ) -> Result<Vec<u8>> {
        // Simulate batch processing
        let batch_size = task
            .input_data
            .metadata
            .get("batch_size")
            .and_then(|s| s.parse::<usize>().ok())
            .unwrap_or(10);

        tracing::debug!(
            "Processing batch of {} items on node {}",
            batch_size,
            node.id
        );

        // Simulate processing time proportional to batch size
        let processing_delay = batch_size * 100; // 100ms per item
        tokio::time::sleep(tokio::time::Duration::from_millis(processing_delay as u64)).await;

        // Generate batch results
        let batch_results = self.generate_batch_results(batch_size).await?;

        Ok(batch_results)
    }

    /// Execute audio processing task
    async fn execute_audio_processing_task(
        &self,
        task: &DistributedTask,
        node: &CloudNode,
    ) -> Result<Vec<u8>> {
        if let Some(audio_data) = &task.input_data.audio_data {
            tracing::debug!(
                "Processing {} bytes of audio data on node {}",
                audio_data.len(),
                node.id
            );

            // Simulate audio processing
            let processing_delay = std::cmp::min(audio_data.len() / 10000, 3000); // Max 3 seconds
            tokio::time::sleep(tokio::time::Duration::from_millis(processing_delay as u64)).await;

            // Generate processed audio
            let processed_audio = self.process_audio_data(audio_data).await?;

            Ok(processed_audio)
        } else {
            Err(anyhow::anyhow!(
                "No audio data provided for audio processing task"
            ))
        }
    }

    /// Execute quality analysis task
    async fn execute_quality_analysis_task(
        &self,
        task: &DistributedTask,
        node: &CloudNode,
    ) -> Result<Vec<u8>> {
        if let Some(audio_data) = &task.input_data.audio_data {
            tracing::debug!(
                "Analyzing quality of {} bytes of audio data on node {}",
                audio_data.len(),
                node.id
            );

            // Simulate quality analysis
            let analysis_delay = std::cmp::min(audio_data.len() / 5000, 2000); // Max 2 seconds
            tokio::time::sleep(tokio::time::Duration::from_millis(analysis_delay as u64)).await;

            // Generate quality analysis results
            let analysis_results = self.analyze_audio_quality(audio_data).await?;

            Ok(analysis_results)
        } else {
            Err(anyhow::anyhow!(
                "No audio data provided for quality analysis task"
            ))
        }
    }

    /// Update task status and move to completed tasks
    async fn update_task_status(&self, task_id: &str, result: Result<TaskResult>) {
        // Remove from active tasks
        {
            let mut active_tasks = self.active_tasks.write().await;
            active_tasks.remove(task_id);
        }

        // Add to completed tasks
        {
            let mut completed_tasks = self.completed_tasks.write().await;
            match result {
                Ok(task_result) => {
                    completed_tasks.insert(task_id.to_string(), task_result);
                }
                Err(e) => {
                    let error_result = TaskResult {
                        task_id: task_id.to_string(),
                        node_id: "unknown".to_string(),
                        success: false,
                        result_data: None,
                        error_message: Some(e.to_string()),
                        processing_time_ms: 0,
                        quality_metrics: None,
                    };
                    completed_tasks.insert(task_id.to_string(), error_result);
                }
            }
        }
    }

    /// Get task status from node
    async fn get_task_status_from_node(
        &self,
        task_id: &str,
        config: &SynthesisConfig,
    ) -> Result<TaskStatus> {
        // Simulate checking task status from remote node
        Ok(TaskStatus {
            task_id: task_id.to_string(),
            node_id: "node-1".to_string(),
            is_complete: false,
            elapsed_ms: 500,
            progress_percentage: 50.0,
        })
    }

    /// Calculate quality metrics for task results
    async fn calculate_quality_metrics(
        &self,
        result_data: &[u8],
        task_type: &TaskType,
    ) -> Option<QualityMetrics> {
        match task_type {
            TaskType::Synthesis | TaskType::VoiceCloning | TaskType::AudioProcessing => {
                // Simulate quality metric calculation
                Some(QualityMetrics {
                    mcd: 2.5 + (result_data.len() as f32 / 100000.0),
                    pesq: 4.2 - (result_data.len() as f32 / 1000000.0),
                    stoi: 0.85 + (result_data.len() as f32 / 10000000.0),
                    naturalness_score: 4.0 + (result_data.len() as f32 / 500000.0),
                })
            }
            _ => None,
        }
    }

    // Helper methods for generating synthetic data
    async fn generate_synthetic_audio(
        &self,
        text: &str,
        config: &SynthesisConfig,
    ) -> Result<Vec<u8>> {
        // Generate synthetic audio data based on text length
        let audio_size = text.len() * 1000; // 1000 bytes per character
        let audio_data = vec![0u8; audio_size];
        Ok(audio_data)
    }

    async fn generate_cloned_voice_model(&self, audio_data: &[u8]) -> Result<Vec<u8>> {
        // Generate a cloned voice model based on input audio
        let model_size = audio_data.len() / 10; // Model is 10% of input size
        let model_data = vec![1u8; model_size];
        Ok(model_data)
    }

    async fn generate_batch_results(&self, batch_size: usize) -> Result<Vec<u8>> {
        // Generate batch processing results
        let result_size = batch_size * 5000; // 5KB per batch item
        let result_data = vec![2u8; result_size];
        Ok(result_data)
    }

    async fn process_audio_data(&self, audio_data: &[u8]) -> Result<Vec<u8>> {
        // Process audio data (e.g., noise reduction, normalization)
        let processed_data = audio_data.iter().map(|&b| b.wrapping_add(1)).collect();
        Ok(processed_data)
    }

    async fn analyze_audio_quality(&self, audio_data: &[u8]) -> Result<Vec<u8>> {
        // Analyze audio quality and generate report
        let analysis_report = format!(
            "Quality analysis of {} bytes of audio data",
            audio_data.len()
        );
        Ok(analysis_report.into_bytes())
    }
}

/// Task status information
#[derive(Debug, Clone)]
struct TaskStatus {
    task_id: String,
    node_id: String,
    is_complete: bool,
    elapsed_ms: u32,
    progress_percentage: f32,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ClusterHealth {
    pub total_nodes: usize,
    pub healthy_nodes: usize,
    pub total_capacity: u32,
    pub current_load: u32,
    pub utilization_percentage: f32,
    pub active_tasks: usize,
    pub average_latency_ms: f32,
}

impl LoadBalancer {
    fn new(strategy: LoadBalancingStrategy) -> Self {
        Self {
            strategy,
            node_scores: Arc::new(RwLock::new(HashMap::new())),
            round_robin_counter: Arc::new(std::sync::atomic::AtomicUsize::new(0)),
        }
    }

    async fn select_node<'a>(
        &self,
        nodes: &[&'a CloudNode],
        task: &DistributedTask,
    ) -> Result<&'a CloudNode> {
        match self.strategy.strategy_type {
            LoadBalancingType::LatencyBased => self.select_lowest_latency_node(nodes),
            LoadBalancingType::CapacityBased => self.select_highest_capacity_node(nodes),
            LoadBalancingType::Adaptive => self.select_adaptive_node(nodes, task).await,
            _ => {
                // Default to round-robin for other strategies
                self.select_round_robin_node(nodes)
            }
        }
    }

    fn select_lowest_latency_node<'a>(&self, nodes: &[&'a CloudNode]) -> Result<&'a CloudNode> {
        nodes
            .iter()
            .min_by_key(|node| node.latency_ms)
            .copied()
            .ok_or_else(|| anyhow::anyhow!("No nodes available"))
    }

    fn select_highest_capacity_node<'a>(&self, nodes: &[&'a CloudNode]) -> Result<&'a CloudNode> {
        nodes
            .iter()
            .filter(|node| node.current_load < node.capacity)
            .max_by_key(|node| node.capacity - node.current_load)
            .copied()
            .ok_or_else(|| anyhow::anyhow!("No available capacity"))
    }

    async fn select_adaptive_node<'a>(
        &self,
        nodes: &[&'a CloudNode],
        _task: &DistributedTask,
    ) -> Result<&'a CloudNode> {
        let weights = &self.strategy.weight_factors;

        let mut best_node = None;
        let mut best_score = f32::NEG_INFINITY;

        for &node in nodes {
            // Calculate composite score based on multiple factors
            let latency_score =
                1.0 / (1.0 + node.latency_ms as f32 / 1000.0) * weights.latency_weight;
            let capacity_score = (node.capacity - node.current_load) as f32 / node.capacity as f32
                * weights.capacity_weight;
            let availability_score = node.availability * weights.availability_weight;

            let total_score = latency_score + capacity_score + availability_score;

            if total_score > best_score {
                best_score = total_score;
                best_node = Some(node);
            }
        }

        best_node.ok_or_else(|| anyhow::anyhow!("No suitable node found"))
    }

    fn select_round_robin_node<'a>(&self, nodes: &[&'a CloudNode]) -> Result<&'a CloudNode> {
        // True round-robin selection with atomic counter
        if nodes.is_empty() {
            return Err(anyhow::anyhow!("No nodes available"));
        }

        // Atomically fetch and increment the counter
        let current_index = self
            .round_robin_counter
            .fetch_add(1, std::sync::atomic::Ordering::Relaxed);

        // Use modulo to wrap around to the beginning
        let index = current_index % nodes.len();

        Ok(nodes[index])
    }
}

impl Default for DistributedConfig {
    fn default() -> Self {
        Self {
            max_concurrent_tasks: 100,
            default_timeout_ms: 30000,
            max_retry_attempts: 3,
            health_check_interval_ms: 10000,
            node_selection_strategy: LoadBalancingStrategy {
                strategy_type: LoadBalancingType::Adaptive,
                weight_factors: WeightFactors {
                    latency_weight: 0.3,
                    capacity_weight: 0.4,
                    availability_weight: 0.2,
                    quality_weight: 0.1,
                },
                failover_enabled: true,
                health_check_interval_ms: 5000,
            },
        }
    }
}

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

    #[tokio::test]
    async fn test_distributed_manager_creation() {
        let config = DistributedConfig::default();
        let manager = DistributedProcessingManager::new(config);

        // Test that manager is created successfully
        assert_eq!(manager.config.max_concurrent_tasks, 100);
    }

    #[tokio::test]
    async fn test_node_registration() {
        let config = DistributedConfig::default();
        let manager = DistributedProcessingManager::new(config);

        let node = CloudNode {
            id: "test-node-1".to_string(),
            endpoint: "https://test.example.com".to_string(),
            capacity: 10,
            current_load: 0,
            capabilities: vec!["synthesis".to_string()],
            region: "us-west-1".to_string(),
            latency_ms: 50,
            availability: 0.99,
        };

        let result = manager.register_node(node).await;
        assert!(result.is_ok());
    }

    #[tokio::test]
    async fn test_cluster_health() {
        let config = DistributedConfig::default();
        let manager = DistributedProcessingManager::new(config);

        let health = manager.get_cluster_health().await;
        assert!(health.is_ok());

        let health = health.unwrap();
        assert_eq!(health.total_nodes, 0);
        assert_eq!(health.healthy_nodes, 0);
    }

    #[test]
    fn test_load_balancing_strategy_serialization() {
        let strategy = LoadBalancingStrategy {
            strategy_type: LoadBalancingType::Adaptive,
            weight_factors: WeightFactors {
                latency_weight: 0.3,
                capacity_weight: 0.4,
                availability_weight: 0.2,
                quality_weight: 0.1,
            },
            failover_enabled: true,
            health_check_interval_ms: 5000,
        };

        let serialized = serde_json::to_string(&strategy);
        assert!(serialized.is_ok());

        let deserialized: Result<LoadBalancingStrategy, _> =
            serde_json::from_str(&serialized.unwrap());
        assert!(deserialized.is_ok());
    }
}