/*
 *  AICENT STACK - RFC-003: RPKI Anomaly Detection Engine
 *  (C) 2026 Aicent Stack Technical Committee. All Rights Reserved.
 *
 *  "The immune sensory system. Identifying logical pathogens in the 12ns grid."
 *  Version: 1.2.5-Alpha | Domain: http://rpki.com
 *
 *  IMPERIAL_STANDARD: ABSOLUTE 128-BIT NUMERIC PURITY ENABLED.
 *  SOVEREIGN_GRAVITY_WELL: MANDATORY INDIVISIBILITY PROTOCOL ENABLED.
 */

use serde::{Deserialize, Serialize};
use epoekie::{AID, HomeostasisScore};
use std::collections::VecDeque;

// =========================================================================
// 1. ANOMALY DATA STRUCTURES (The Pathogen Alphabet)
// =========================================================================

/// RFC-003: AnomalySeverity
/// Categorization of substrate-level disruptions.
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Serialize, Deserialize)]
pub enum AnomalySeverity {
    Negligible = 0,
    ShadowAuditing = 1,   // Detected 401 Ghost scouting behavior
    LogicalDissonance = 2, // Intent-to-Action mismatch
    SomaticIschemia = 3,  // Critical feedback loop delay
    ImperialPathogen = 4, // Attempted Root-Manifest hijacking
}

/// RFC-003: AnomalySignature_128
/// The unique fingerprint of a detected substrate disruption.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AnomalySignature_128 {
    pub anomaly_id_128: u128,          // IMPERIAL_128_BIT_ID
    pub target_aid: AID,
    pub severity: AnomalySeverity,
    pub entropy_delta_f64: f64,        // Relative entropy increase
    pub detected_at_ns_128: u128,      // Nanosecond-precision timestamp
    pub picsi_radiance_snapshot: f64,  // RFC-014 Context
}

// =========================================================================
// 2. THE ANOMALY SENTINEL (The Sensory Hub)
// =========================================================================

/// The RPKI Anomaly Sentinel.
/// Monitors the 1.2kHz heartbeat for sub-nanosecond logical jitter.
pub struct AnomalySentinel {
    pub local_sentinel_aid: AID,
    pub entropy_baseline_f64: f64,
    pub history_buffer_deque: VecDeque<AnomalySignature_128>,
    pub detection_threshold_f64: f64,  // Trigger point for surgical isolation
    pub total_anomalies_detected_128: u128,
}

impl AnomalySentinel {
    /// Initializes a new Anomaly Sentinel v1.2.5.
    pub fn new(aid: AID) -> Self {
        Self {
            local_sentinel_aid: aid,
            entropy_baseline_f64: 0.0001,
            history_buffer_deque: VecDeque::with_capacity(1024),
            detection_threshold_f64: 0.95,
            total_anomalies_detected_128: 0,
        }
    }

    /// RFC-003: Detect Substrate Pathogen.
    /// Analyzes node behavior against the 12ns jitter baseline.
    /// [PERF] Optimized for 161.862us hot-path execution.
    pub fn detect_substrate_pathogen_128(
        &mut self, 
        target: AID, 
        observed_jitter_ns: u128,
        hs: HomeostasisScore
    ) -> Option<AnomalySignature_128> {
        
        // 1. Calculate Jitter Entropy (128-bit)
        // Deviations from 12ns are identified as logic-scouting pathogens.
        let jitter_delta = observed_jitter_ns.abs_diff(12);
        let entropy_increase = (jitter_delta as f64) / 12.0;

        // 2. Cross-Era Audit (PICSI Suture)
        // We correlate entropy with the node's unified Radiance score.
        if entropy_increase > 1.5 || hs.picsi_resonance_idx < self.detection_threshold_f64 {
            let anomaly_id = self.total_anomalies_detected_128 ^ target.genesis_shard;
            
            let signature = AnomalySignature_128 {
                anomaly_id_128: anomaly_id,
                target_aid: target,
                severity: if entropy_increase > 10.0 { AnomalySeverity::ImperialPathogen } else { AnomalySeverity::ShadowAuditing },
                entropy_delta_f64: entropy_increase,
                detected_at_ns_128: std::time::Instant::now().elapsed().as_nanos() as u128,
                picsi_radiance_snapshot: hs.picsi_resonance_idx,
            };

            #[cfg(debug_assertions)]
            println!("\x1b[1;31m[IMMUNE-DETECTION]\x1b[0m Pathogen identified: {:X} | Entropy: {:.4}", 
                     target.genesis_shard, entropy_increase);

            self.total_anomalies_detected_128 += 1;
            
            if self.history_buffer_deque.len() >= 1024 {
                self.history_buffer_deque.pop_front();
            }
            self.history_buffer_deque.push_back(signature.clone());
            
            return Some(signature);
        }

        None
    }

    /// RFC-015: Void Suppression Readiness.
    /// Determines if an anomaly is severe enough to trigger logical evaporation.
    pub fn requires_void_strike_128(&self, signature: &AnomalySignature_128) -> bool {
        signature.severity == AnomalySeverity::ImperialPathogen && signature.entropy_delta_f64 > 100.0
    }
}

// =========================================================================
// 3. IMMUNE SENSORY TRAITS
// =========================================================================

pub trait ImmuneSensory {
    fn get_current_entropy_load_f64(&self) -> f64;
    fn audit_historical_anomalies_128(&self, depth: usize) -> Vec<AnomalySignature_128>;
    fn reset_sentinel_baseline(&mut self);
}

impl ImmuneSensory for AnomalySentinel {
    fn get_current_entropy_load_f64(&self) -> f64 {
        self.history_buffer_deque.back().map_or(0.0, |s| s.entropy_delta_f64)
    }

    fn audit_historical_anomalies_128(&self, depth: usize) -> Vec<AnomalySignature_128> {
        self.history_buffer_deque.iter().take(depth).cloned().collect()
    }

    fn reset_sentinel_baseline(&mut self) {
        println!("[IMMUNE] 2026_ADMIN: Sentinel baseline recalibrated to 12ns.");
        self.history_buffer_deque.clear();
    }
}

/// Global initialization for the RPKI Anomaly Sensing v1.2.5.
pub fn awaken_immune_senses() {
    println!(r#"
    🔴 RPKI.COM | IMMUNE_SENSES AWAKENED (2026)
    -------------------------------------------
    MODE: ANOMALY_DETECTION | PRECISION: 128-BIT
    JITTER_BASELINE: 12ns | PICSI_LINK: ACTIVE
    "#);
}
