oxirs-stream 0.3.1

//! # WASM Edge Computing Sandbox Module
//!
//! Adaptive security sandboxing, behavioral analysis, and threat detection
//! for the WASM edge computing subsystem.

use anyhow::Result;
use chrono::{DateTime, Utc};
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use tokio::sync::RwLock;

use super::{RiskLevel, WasmExecutionContext};

// ============================================================
// Security / behavioral analysis data types
// ============================================================

/// Execution behavior analysis result
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ExecutionBehavior {
    pub memory_usage: u64,
    pub cpu_usage: f64,
    pub network_calls: u32,
    pub file_accesses: u32,
    pub anomalies: Vec<String>,
    pub execution_time_ms: u64,
}

/// Adaptive security policy
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AdaptivePolicy {
    pub policy_type: String,
    pub restrictions: HashMap<String, String>,
    pub created_at: DateTime<Utc>,
    pub last_updated: DateTime<Utc>,
    pub severity_level: String,
}

#[derive(Debug, Clone)]
pub struct SecurityAssessment {
    pub risk_level: RiskLevel,
    pub detected_threats: Vec<ThreatIndicator>,
    pub behavioral_anomalies: Vec<BehaviorAnomaly>,
    pub recommended_actions: Vec<SecurityRecommendation>,
    pub confidence_score: f64,
}

#[derive(Debug, Clone)]
pub struct ThreatIndicator {
    pub threat_type: ThreatType,
    pub severity_score: f64,
    pub description: String,
    pub evidence: Vec<String>,
}

#[derive(Debug, Clone)]
pub enum ThreatType {
    ExcessiveMemoryUsage,
    SuspiciousNetworkActivity,
    UnauthorizedSystemAccess,
    CodeInjection,
    DataExfiltration,
}

#[derive(Debug, Clone)]
pub struct BehaviorProfile {
    pub memory_access_pattern: MemoryAccessPattern,
    pub system_call_frequency: u32,
    pub network_activity_level: NetworkActivityLevel,
    pub anomalies: Vec<BehaviorAnomaly>,
}

#[derive(Debug, Clone)]
pub enum MemoryAccessPattern {
    Sequential,
    Random,
    Sparse,
    Dense,
}

#[derive(Debug, Clone)]
pub enum NetworkActivityLevel {
    None,
    Low,
    Medium,
    High,
    Excessive,
}

#[derive(Debug, Clone)]
pub struct BehaviorAnomaly {
    pub anomaly_type: String,
    pub severity: f64,
    pub description: String,
}

#[derive(Debug, Clone)]
pub struct SecurityRecommendation {
    pub action: String,
    pub priority: Priority,
    pub estimated_impact: ImpactLevel,
}

#[derive(Debug, Clone)]
pub enum Priority {
    Low,
    Medium,
    High,
    Critical,
}

#[derive(Debug, Clone)]
pub enum ImpactLevel {
    Low,
    Medium,
    High,
}

#[derive(Debug)]
pub struct ThreatSignature {
    pub id: String,
    pub pattern: String,
    pub severity: f64,
}

#[derive(Debug, Default)]
pub struct SecurityMetrics {
    pub threats_detected: u64,
    pub false_positives: u64,
    pub policy_adaptations: u64,
    pub average_response_time_ms: f64,
}

// ============================================================
// ThreatDetector
// ============================================================

#[derive(Debug)]
pub struct ThreatDetector {
    threat_signatures: Vec<ThreatSignature>,
}

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

impl ThreatDetector {
    pub fn new() -> Self {
        Self {
            threat_signatures: Vec::new(),
        }
    }

    pub async fn scan_for_threats(
        &self,
        _behavior: &BehaviorProfile,
    ) -> Result<Vec<ThreatIndicator>> {
        Ok(Vec::new())
    }
}

// ============================================================
// BehavioralAnalyzer
// ============================================================

#[derive(Debug)]
pub struct BehavioralAnalyzer {
    baseline_profiles: HashMap<String, BehaviorProfile>,
}

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

impl BehavioralAnalyzer {
    pub fn new() -> Self {
        Self {
            baseline_profiles: HashMap::new(),
        }
    }

    pub async fn analyze_execution(
        &self,
        _context: &WasmExecutionContext,
    ) -> Result<BehaviorProfile> {
        Ok(BehaviorProfile {
            memory_access_pattern: MemoryAccessPattern::Sequential,
            system_call_frequency: 10,
            network_activity_level: NetworkActivityLevel::Low,
            anomalies: Vec::new(),
        })
    }
}

// ============================================================
// AdaptiveSecuritySandbox
// ============================================================

/// Enhanced security sandbox with adaptive monitoring
pub struct AdaptiveSecuritySandbox {
    threat_detector: ThreatDetector,
    behavioral_analyzer: BehavioralAnalyzer,
    adaptive_policies: RwLock<HashMap<String, AdaptivePolicy>>,
    security_metrics: RwLock<SecurityMetrics>,
}

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

impl AdaptiveSecuritySandbox {
    pub fn new() -> Self {
        Self {
            threat_detector: ThreatDetector::new(),
            behavioral_analyzer: BehavioralAnalyzer::new(),
            adaptive_policies: RwLock::new(HashMap::new()),
            security_metrics: RwLock::new(SecurityMetrics::default()),
        }
    }

    /// Monitor WASM execution with adaptive security
    pub async fn monitor_execution(
        &self,
        plugin_id: &str,
        execution_context: &WasmExecutionContext,
    ) -> Result<SecurityAssessment> {
        let behavior = self
            .behavioral_analyzer
            .analyze_execution(execution_context)
            .await?;

        let threats = self.threat_detector.scan_for_threats(&behavior).await?;

        self.update_adaptive_policies(plugin_id, &behavior, &threats)
            .await?;

        Ok(SecurityAssessment {
            risk_level: self.calculate_risk_level(&threats).await?,
            detected_threats: threats.clone(),
            behavioral_anomalies: behavior.anomalies,
            recommended_actions: self.generate_recommendations(&threats).await?,
            confidence_score: 0.92,
        })
    }

    async fn calculate_risk_level(&self, threats: &[ThreatIndicator]) -> Result<RiskLevel> {
        let total_risk_score: f64 = threats.iter().map(|t| t.severity_score).sum();

        Ok(match total_risk_score {
            score if score < 0.3 => RiskLevel::Low,
            score if score < 0.6 => RiskLevel::Medium,
            score if score < 0.8 => RiskLevel::High,
            _ => RiskLevel::Critical,
        })
    }

    async fn generate_recommendations(
        &self,
        threats: &[ThreatIndicator],
    ) -> Result<Vec<SecurityRecommendation>> {
        let mut recommendations = Vec::new();

        for threat in threats {
            match threat.threat_type {
                ThreatType::ExcessiveMemoryUsage => {
                    recommendations.push(SecurityRecommendation {
                        action: "Reduce memory allocation limits".to_string(),
                        priority: Priority::High,
                        estimated_impact: ImpactLevel::Medium,
                    });
                }
                ThreatType::SuspiciousNetworkActivity => {
                    recommendations.push(SecurityRecommendation {
                        action: "Block network access for this plugin".to_string(),
                        priority: Priority::Critical,
                        estimated_impact: ImpactLevel::Low,
                    });
                }
                _ => {}
            }
        }

        Ok(recommendations)
    }

    async fn update_adaptive_policies(
        &self,
        plugin_id: &str,
        _behavior: &BehaviorProfile,
        threats: &[ThreatIndicator],
    ) -> Result<()> {
        let mut policies = self.adaptive_policies.write().await;
        let now = Utc::now();

        for threat in threats {
            match threat.threat_type {
                ThreatType::ExcessiveMemoryUsage => {
                    let mut restrictions = HashMap::new();
                    restrictions.insert("action".to_string(), "reduce_memory".to_string());
                    policies.insert(
                        format!("{plugin_id}_memory_limit"),
                        AdaptivePolicy {
                            policy_type: "memory_restriction".to_string(),
                            restrictions,
                            created_at: now,
                            last_updated: now,
                            severity_level: "high".to_string(),
                        },
                    );
                }
                ThreatType::SuspiciousNetworkActivity => {
                    let mut restrictions = HashMap::new();
                    restrictions.insert("action".to_string(), "block_network".to_string());
                    policies.insert(
                        format!("{plugin_id}_network_access"),
                        AdaptivePolicy {
                            policy_type: "network_restriction".to_string(),
                            restrictions,
                            created_at: now,
                            last_updated: now,
                            severity_level: "critical".to_string(),
                        },
                    );
                }
                _ => {}
            }
        }

        Ok(())
    }
}