pub mod contracts;
pub mod lifetime_analysis;
pub mod memory_safety;
pub mod properties;
pub mod quickcheck;

use anyhow::Result;
use depyler_core::hir::HirFunction;
use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PropertyVerifier {
    pub enable_quickcheck: bool,
    pub enable_contracts: bool,
    pub test_iterations: usize,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct VerificationResult {
    pub property: String,
    pub status: PropertyStatus,
    pub confidence: f64,
    pub method: VerificationMethod,
    pub counterexamples: Vec<TestCase>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum PropertyStatus {
    Proven,
    HighConfidence,
    Likely,
    Unknown,
    Violated(String),
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum VerificationMethod {
    Exhaustive,
    PropertyTesting,
    StaticAnalysis,
    StructuralInduction,
    Heuristic,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TestCase {
    pub inputs: Vec<serde_json::Value>,
    pub expected_output: Option<serde_json::Value>,
    pub actual_output: Option<serde_json::Value>,
    pub error: Option<String>,
}

impl Default for PropertyVerifier {
    fn default() -> Self {
        Self {
            enable_quickcheck: true,
            enable_contracts: true,
            test_iterations: 1000,
        }
    }
}

impl PropertyVerifier {
    pub fn new() -> Self {
        Self::default()
    }

    pub fn with_iterations(mut self, iterations: usize) -> Self {
        self.test_iterations = iterations;
        self
    }

    pub fn verify_function(&self, func: &HirFunction) -> Vec<VerificationResult> {
        let mut results = vec![];

        // Property 1: Type preservation
        if let Some(result) = self.verify_type_preservation(func) {
            results.push(result);
        }

        // Property 2: Memory safety
        let mut memory_analyzer = memory_safety::MemorySafetyAnalyzer::new();
        results.push(memory_analyzer.analyze_function(func));

        // Property 2b: Lifetime safety
        let mut lifetime_analyzer = lifetime_analysis::LifetimeAnalyzer::new();
        let lifetime_violations = lifetime_analyzer.analyze_function(func);
        if lifetime_violations.is_empty() {
            results.push(VerificationResult {
                property: "lifetime_safety".into(),
                status: PropertyStatus::Proven,
                confidence: 1.0,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            });
        } else {
            results.push(VerificationResult {
                property: "lifetime_safety".into(),
                status: PropertyStatus::Violated(format!(
                    "{} lifetime violations found",
                    lifetime_violations.len()
                )),
                confidence: 1.0,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            });
        }

        // Property 3: Null safety
        let null_violations = memory_safety::check_null_safety(func);
        if null_violations.is_empty() {
            results.push(VerificationResult {
                property: "null_safety".into(),
                status: PropertyStatus::Proven,
                confidence: 1.0,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            });
        } else {
            results.push(VerificationResult {
                property: "null_safety".into(),
                status: PropertyStatus::Violated(format!(
                    "{} violations found",
                    null_violations.len()
                )),
                confidence: 1.0,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            });
        }

        // Property 4: Panic freedom
        if func.properties.panic_free {
            results.push(VerificationResult {
                property: "panic_free".into(),
                status: PropertyStatus::HighConfidence,
                confidence: 0.95,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            });
        }

        // Property 5: Termination
        if func.properties.always_terminates {
            results.push(VerificationResult {
                property: "termination".into(),
                status: PropertyStatus::Proven,
                confidence: 1.0,
                method: VerificationMethod::StructuralInduction,
                counterexamples: vec![],
            });
        }

        // Property 6: Purity
        if func.properties.is_pure {
            results.push(VerificationResult {
                property: "pure".into(),
                status: PropertyStatus::HighConfidence,
                confidence: 0.9,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            });
        }

        // Property 7: Thread safety (if required)
        if func.annotations.thread_safety == depyler_annotations::ThreadSafety::Required {
            results.push(self.verify_thread_safety(func));
        }

        results
    }

    fn verify_type_preservation(&self, func: &HirFunction) -> Option<VerificationResult> {
        // Check if all types are properly annotated
        let all_typed = func
            .params
            .iter()
            .all(|(_, ty)| !matches!(ty, depyler_core::hir::Type::Unknown));

        if all_typed && !matches!(func.ret_type, depyler_core::hir::Type::Unknown) {
            Some(VerificationResult {
                property: "type_preservation".into(),
                status: PropertyStatus::Proven,
                confidence: 1.0,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            })
        } else {
            Some(VerificationResult {
                property: "type_preservation".into(),
                status: PropertyStatus::Unknown,
                confidence: 0.0,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            })
        }
    }

    fn verify_thread_safety(&self, func: &HirFunction) -> VerificationResult {
        // Check for proper synchronization when thread safety is required
        let has_shared_state = self.detect_shared_state(func);
        let has_proper_sync = func.annotations.interior_mutability
            == depyler_annotations::InteriorMutability::ArcMutex;

        if !has_shared_state || has_proper_sync {
            VerificationResult {
                property: "thread_safety".into(),
                status: PropertyStatus::Proven,
                confidence: 0.95,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            }
        } else {
            VerificationResult {
                property: "thread_safety".into(),
                status: PropertyStatus::Violated(
                    "Shared state without proper synchronization".to_string(),
                ),
                confidence: 1.0,
                method: VerificationMethod::StaticAnalysis,
                counterexamples: vec![],
            }
        }
    }

    fn detect_shared_state(&self, func: &HirFunction) -> bool {
        // Simplified check - in reality would analyze data flow
        func.annotations.ownership_model == depyler_annotations::OwnershipModel::Shared
    }

    pub fn generate_property_tests(&self, func: &HirFunction) -> Result<String> {
        let test_code = properties::generate_quickcheck_tests(func, self.test_iterations)?;
        Ok(test_code)
    }
}
