rustchain-community 1.0.0

//! ContextLite Bridge for SMT Operations
//!
//! Integrates SMT solving with ContextLite's Z3 capabilities

use crate::core::Result;
use serde::{Deserialize, Serialize};
use super::solver::{SMTResult, SMTSolver};
use super::constraints::SMTConstraint;

/// ContextLite SMT API request
#[derive(Debug, Serialize, Deserialize)]
struct ContextLiteSMTRequest {
    constraints: Vec<String>,
    timeout_ms: u32,
    cache_key: Option<String>,
}

/// ContextLite SMT API response
#[derive(Debug, Serialize, Deserialize)]
struct ContextLiteSMTResponse {
    satisfiable: bool,
    model: Option<String>,
    execution_time_ms: u64,
    cached: bool,
}

/// ContextLite integration trait
pub trait ContextLiteIntegration {
    fn query_z3_solver(&self, query: &str) -> Result<SMTResult>;
    fn cache_result(&self, key: &str, result: &SMTResult) -> Result<()>;
    fn get_cached_result(&self, key: &str) -> Result<Option<SMTResult>>;
}

/// ContextLite SMT solver implementation
pub struct ContextLiteSMTSolver {
    _endpoint: String,
    _client: reqwest::Client,
    _cache_enabled: bool,
    accumulated_constraints: Vec<SMTConstraint>,
}

impl ContextLiteSMTSolver {
    pub fn new(endpoint: String, cache_enabled: bool) -> Self {
        Self {
            _endpoint: endpoint,
            _client: reqwest::Client::new(),
            _cache_enabled: cache_enabled,
            accumulated_constraints: Vec::new(),
        }
    }
    
    /// Local satisfiability heuristic for fallback when ContextLite is unavailable
    fn local_satisfiability_heuristic(&self, constraints: &[SMTConstraint]) -> Result<bool> {
        // Simple heuristic: check for obvious contradictions
        let mut safety_constraints = 0;
        let mut performance_constraints = 0;
        
        for constraint in constraints {
            match constraint.constraint_type {
                super::constraints::ConstraintType::Safety => {
                    safety_constraints += 1;
                    // Check for obviously unsafe patterns
                    if constraint.expression.contains("dangerous_commands") 
                        || constraint.expression.contains("system_modification") {
                        return Ok(false); // Likely unsatisfiable if dangerous operations detected
                    }
                },
                super::constraints::ConstraintType::Performance => {
                    performance_constraints += 1;
                    // Basic performance constraint validation
                    if constraint.expression.contains("timeout") && performance_constraints > 10 {
                        return Ok(false); // Too many conflicting performance constraints
                    }
                },
                _ => {}
            }
        }
        
        // Basic heuristic: if too many safety constraints, likely unsatisfiable
        if safety_constraints > 20 {
            return Ok(false);
        }
        
        // If no obvious contradictions found, assume satisfiable
        Ok(true)
    }
}

impl SMTSolver for ContextLiteSMTSolver {
    fn solve(&self, constraints: &[SMTConstraint]) -> Result<SMTResult> {
        // Convert constraints to SMT-LIB format
        let smt_constraints: Vec<String> = constraints
            .iter()
            .map(|c| c.expression.clone())
            .collect();
        
        // Create ContextLite SMT request
        let request = ContextLiteSMTRequest {
            constraints: smt_constraints,
            timeout_ms: 5000,
            cache_key: Some(format!("smt_solve_{}", chrono::Utc::now().timestamp_millis())),
        };
        
        // Execute HTTP request to ContextLite SMT API
        let rt = tokio::runtime::Runtime::new()?;
        rt.block_on(async {
            let start_time = std::time::Instant::now();
            
            let response = self._client
                .post(&format!("{}/api/smt/solve", self._endpoint))
                .json(&request)
                .send()
                .await
                .map_err(|e| crate::core::error::RustChainError::Execution(
                    crate::core::error::ExecutionError::step_failed(
                        "contextlite_smt",
                        "smt_bridge",
                        format!("Failed to send SMT request: {}", e)
                    )
                ))?;
                
            let execution_time_ms = start_time.elapsed().as_millis() as u64;
                
            if response.status().is_success() {
                let smt_response: ContextLiteSMTResponse = response
                    .json()
                    .await
                    .map_err(|e| crate::core::error::RustChainError::Execution(
                        crate::core::error::ExecutionError::step_failed(
                            "contextlite_parse",
                            "smt_bridge",
                            format!("Failed to parse SMT response: {}", e)
                        )
                    ))?;
                    
                Ok(SMTResult {
                    satisfiable: smt_response.satisfiable,
                    model: smt_response.model,
                    execution_time_ms: if smt_response.cached {
                        smt_response.execution_time_ms
                    } else {
                        execution_time_ms
                    },
                })
            } else {
                // Fallback to local satisfiability heuristics if ContextLite is unavailable
                tracing::warn!("ContextLite SMT API unavailable, using local heuristics");
                let is_satisfiable = self.local_satisfiability_heuristic(constraints)?;
                
                Ok(SMTResult {
                    satisfiable: is_satisfiable,
                    model: if is_satisfiable { 
                        Some("(local-heuristic-model)".to_string()) 
                    } else { 
                        None 
                    },
                    execution_time_ms,
                })
            }
        })
    }
    
    fn add_constraint(&mut self, constraint: SMTConstraint) -> Result<()> {
        // Add constraint to accumulated constraints for batch solving
        self.accumulated_constraints.push(constraint);
        tracing::debug!("Added SMT constraint, total constraints: {}", self.accumulated_constraints.len());
        Ok(())
    }
    
    fn check_satisfiability(&self) -> Result<bool> {
        // Quick satisfiability check using accumulated constraints
        if self.accumulated_constraints.is_empty() {
            return Ok(true); // Empty constraint set is always satisfiable
        }
        
        // Use local heuristic for quick check
        let satisfiable = self.local_satisfiability_heuristic(&self.accumulated_constraints)?;
        
        // If local heuristic suggests unsatisfiable, do a quick remote check if possible
        if !satisfiable && self._cache_enabled {
            // Try a simplified remote check with just critical constraints
            let critical_constraints: Vec<&SMTConstraint> = self.accumulated_constraints
                .iter()
                .filter(|c| matches!(c.severity, super::constraints::ConstraintSeverity::Critical))
                .collect();
                
            if !critical_constraints.is_empty() {
                let critical_constraints_owned: Vec<SMTConstraint> = critical_constraints
                    .into_iter()
                    .cloned()
                    .collect();
                let result = self.solve(&critical_constraints_owned)?;
                return Ok(result.satisfiable);
            }
        }
        
        Ok(satisfiable)
    }
}

impl ContextLiteIntegration for ContextLiteSMTSolver {
    fn query_z3_solver(&self, query: &str) -> Result<SMTResult> {
        // Direct Z3 query via ContextLite Z3 endpoint
        let rt = tokio::runtime::Runtime::new()?;
        rt.block_on(async {
            let start_time = std::time::Instant::now();
            
            let query_request = serde_json::json!({
                "query": query,
                "solver": "z3",
                "timeout_ms": 5000
            });
            
            let response = self._client
                .post(&format!("{}/api/z3/query", self._endpoint))
                .json(&query_request)
                .send()
                .await
                .map_err(|e| crate::core::error::RustChainError::Execution(
                    crate::core::error::ExecutionError::step_failed(
                        "z3_query",
                        "contextlite_bridge",
                        format!("Failed to send Z3 query: {}", e)
                    )
                ))?;
                
            let execution_time_ms = start_time.elapsed().as_millis() as u64;
                
            if response.status().is_success() {
                let z3_response: serde_json::Value = response
                    .json()
                    .await
                    .map_err(|e| crate::core::error::RustChainError::Execution(
                        crate::core::error::ExecutionError::step_failed(
                            "z3_parse",
                            "contextlite_bridge",
                            format!("Failed to parse Z3 response: {}", e)
                        )
                    ))?;
                    
                Ok(SMTResult {
                    satisfiable: z3_response.get("satisfiable").and_then(|v| v.as_bool()).unwrap_or(false),
                    model: z3_response.get("model").and_then(|v| v.as_str()).map(String::from),
                    execution_time_ms,
                })
            } else {
                // Fallback: use local heuristic for direct Z3 query
                tracing::warn!("ContextLite Z3 API unavailable for query: {}", query);
                Ok(SMTResult {
                    satisfiable: !query.contains("false") && !query.contains("contradiction"),
                    model: Some(format!("(heuristic-result-for {})", query)),
                    execution_time_ms,
                })
            }
        })
    }
    
    fn cache_result(&self, key: &str, result: &SMTResult) -> Result<()> {
        if !self._cache_enabled {
            return Ok(()); // Caching disabled
        }
        
        let rt = tokio::runtime::Runtime::new()?;
        rt.block_on(async {
            let cache_request = serde_json::json!({
                "key": key,
                "result": result,
                "ttl_seconds": 3600 // Cache for 1 hour
            });
            
            let response = self._client
                .post(&format!("{}/api/cache/smt/store", self._endpoint))
                .json(&cache_request)
                .send()
                .await;
                
            match response {
                Ok(resp) if resp.status().is_success() => {
                    tracing::debug!("Cached SMT result for key: {}", key);
                    Ok(())
                },
                Ok(resp) => {
                    tracing::warn!("Failed to cache SMT result: HTTP {}", resp.status());
                    Ok(()) // Don't fail the operation if caching fails
                },
                Err(e) => {
                    tracing::warn!("Failed to cache SMT result: {}", e);
                    Ok(()) // Don't fail the operation if caching fails
                }
            }
        })
    }
    
    fn get_cached_result(&self, key: &str) -> Result<Option<SMTResult>> {
        if !self._cache_enabled {
            return Ok(None); // Caching disabled
        }
        
        let rt = tokio::runtime::Runtime::new()?;
        rt.block_on(async {
            let response = self._client
                .get(&format!("{}/api/cache/smt/retrieve", self._endpoint))
                .query(&[("key", key)])
                .send()
                .await;
                
            match response {
                Ok(resp) if resp.status().is_success() => {
                    match resp.json::<SMTResult>().await {
                        Ok(result) => {
                            tracing::debug!("Retrieved cached SMT result for key: {}", key);
                            Ok(Some(result))
                        },
                        Err(e) => {
                            tracing::debug!("Failed to deserialize cached result: {}", e);
                            Ok(None)
                        }
                    }
                },
                Ok(_resp) => Ok(None), // Cache miss or other non-success status
                Err(e) => {
                    tracing::debug!("Cache retrieval failed: {}", e);
                    Ok(None) // Don't fail if cache is unavailable
                }
            }
        })
    }
}