microscope-memory 0.6.1

//! Dream Consolidation for Microscope Memory.
//!
//! An offline process that replays the day's recall patterns during idle time,
//! strengthening important pathways and pruning weak ones — analogous to how
//! biological sleep consolidates memories.
//!
//! Binary format: dream_log.bin (DRM1)

use std::fs;
use std::path::Path;
use std::time::{SystemTime, UNIX_EPOCH};

use crate::hebbian::HebbianState;
use crate::predictive_cache::PredictiveCache;
use crate::resonance::ResonanceState;
use crate::thought_graph::ThoughtGraphState;

// ─── Constants ──────────────────────────────────────

/// Replay window: consider fingerprints from the last 24h.
const REPLAY_WINDOW_MS: u64 = 86_400_000;

/// Co-activation pairs seen only this many times AND older than PRUNE_AGE are pruned.
const COACTIVATION_PRUNE_THRESHOLD: u32 = 1;

/// Prune age: 48h.
const PRUNE_AGE_MS: u64 = 172_800_000;

/// Activation records with energy below this are pruned (zeroed).
const ACTIVATION_PRUNE_ENERGY: f32 = 0.001;

/// Dream replay gives partial energy (lighter than real activation).
const REPLAY_ENERGY: f32 = 0.3;

/// Co-activation pairs seen in 3+ replayed fingerprints get strengthened.
const STRENGTHEN_MIN_APPEARANCES: usize = 3;

/// Multiplier for strengthened co-activation pairs.
const STRENGTHEN_MULTIPLIER: f32 = 1.5;

/// Resonance field decay factor during dream.
const FIELD_DREAM_DECAY: f32 = 0.8;

// ─── Types ──────────────────────────────────────────

/// Record of a single dream consolidation cycle.
#[derive(Clone, Debug)]
pub struct DreamCycle {
    pub timestamp_ms: u64,
    pub duration_ms: u32,
    pub replayed_fingerprints: u32,
    pub strengthened_pairs: u32,
    pub pruned_pairs: u32,
    pub pruned_activations: u32,
    pub consolidated_patterns: u32,
    pub energy_before: f32,
    pub energy_after: f32,
}

/// Persistent dream consolidation log.
pub struct DreamState {
    pub cycles: Vec<DreamCycle>,
    pub last_dream_ms: u64,
}

pub struct DreamStats {
    pub total_cycles: usize,
    pub last_dream_ms: u64,
    pub total_pruned_pairs: u64,
    pub total_pruned_activations: u64,
    pub total_strengthened: u64,
    pub total_replayed: u64,
}

// ─── DreamState I/O ─────────────────────────────────

const CYCLE_BYTES: usize = 40; // 8+4+4+4+4+4+4+4+4

impl DreamState {
    pub fn load_or_init(output_dir: &Path) -> Self {
        let path = output_dir.join("dream_log.bin");
        if let Ok(data) = fs::read(&path) {
            if data.len() >= 16 && &data[0..4] == b"DRM1" {
                let cycle_count = read_u32(&data, 4) as usize;
                let last_dream_ms = read_u64(&data, 8);
                let mut cycles = Vec::with_capacity(cycle_count);
                for i in 0..cycle_count {
                    let off = 16 + i * CYCLE_BYTES;
                    if off + CYCLE_BYTES > data.len() {
                        break;
                    }
                    cycles.push(DreamCycle {
                        timestamp_ms: read_u64(&data, off),
                        duration_ms: read_u32(&data, off + 8),
                        replayed_fingerprints: read_u32(&data, off + 12),
                        strengthened_pairs: read_u32(&data, off + 16),
                        pruned_pairs: read_u32(&data, off + 20),
                        pruned_activations: read_u32(&data, off + 24),
                        consolidated_patterns: read_u32(&data, off + 28),
                        energy_before: read_f32(&data, off + 32),
                        energy_after: read_f32(&data, off + 36),
                    });
                }
                return Self {
                    cycles,
                    last_dream_ms,
                };
            }
        }
        Self {
            cycles: Vec::new(),
            last_dream_ms: 0,
        }
    }

    pub fn save(&self, output_dir: &Path) -> Result<(), String> {
        let path = output_dir.join("dream_log.bin");
        let mut buf = Vec::with_capacity(16 + self.cycles.len() * CYCLE_BYTES);
        buf.extend_from_slice(b"DRM1");
        buf.extend_from_slice(&(self.cycles.len() as u32).to_le_bytes());
        buf.extend_from_slice(&self.last_dream_ms.to_le_bytes());
        for c in &self.cycles {
            buf.extend_from_slice(&c.timestamp_ms.to_le_bytes());
            buf.extend_from_slice(&c.duration_ms.to_le_bytes());
            buf.extend_from_slice(&c.replayed_fingerprints.to_le_bytes());
            buf.extend_from_slice(&c.strengthened_pairs.to_le_bytes());
            buf.extend_from_slice(&c.pruned_pairs.to_le_bytes());
            buf.extend_from_slice(&c.pruned_activations.to_le_bytes());
            buf.extend_from_slice(&c.consolidated_patterns.to_le_bytes());
            buf.extend_from_slice(&c.energy_before.to_le_bytes());
            buf.extend_from_slice(&c.energy_after.to_le_bytes());
        }
        fs::write(&path, &buf).map_err(|e| format!("write dream_log.bin: {}", e))
    }

    pub fn stats(&self) -> DreamStats {
        DreamStats {
            total_cycles: self.cycles.len(),
            last_dream_ms: self.last_dream_ms,
            total_pruned_pairs: self.cycles.iter().map(|c| c.pruned_pairs as u64).sum(),
            total_pruned_activations: self
                .cycles
                .iter()
                .map(|c| c.pruned_activations as u64)
                .sum(),
            total_strengthened: self
                .cycles
                .iter()
                .map(|c| c.strengthened_pairs as u64)
                .sum(),
            total_replayed: self
                .cycles
                .iter()
                .map(|c| c.replayed_fingerprints as u64)
                .sum(),
        }
    }
}

// ─── Dream Consolidation ─────────────────────────────

/// Run a full dream consolidation cycle.
/// 1. Replay recent fingerprints (partial energy boost)
/// 2. Strengthen co-activation pairs appearing in 3+ replayed fingerprints
/// 3. Prune weak co-activation pairs (count=1, older than 48h)
/// 4. Prune cold activation records (zero energy, zero count)
/// 5. Detect thought patterns across recent sessions
/// 6. Decay resonance field
/// 7. Clean up expired predictive cache entries
pub fn dream_consolidate(output_dir: &Path, block_count: usize) -> Result<DreamCycle, String> {
    let t0 = now_ms();

    let mut hebb = HebbianState::load_or_init(output_dir, block_count);
    let mut thought_graph = ThoughtGraphState::load_or_init(output_dir);
    let mut pred_cache = PredictiveCache::load_or_init(output_dir);
    let mut resonance = ResonanceState::load_or_init(output_dir);

    // Measure energy before
    let energy_before: f32 = hebb.activations.iter().map(|r| r.energy).sum();

    // Step 1: Replay recent fingerprints
    let cutoff = t0.saturating_sub(REPLAY_WINDOW_MS);
    let recent_fps: Vec<_> = hebb
        .fingerprints
        .iter()
        .filter(|fp| fp.timestamp_ms >= cutoff)
        .cloned()
        .collect();
    let replayed_count = recent_fps.len() as u32;

    // Count how many fingerprints each co-activation pair appears in
    let mut pair_appearances: std::collections::HashMap<(u32, u32), usize> =
        std::collections::HashMap::new();

    for fp in &recent_fps {
        // Replay: partial energy boost
        for &(block_idx, _score) in &fp.activations {
            let idx = block_idx as usize;
            if idx < hebb.activations.len() {
                let rec = &mut hebb.activations[idx];
                // Boost energy, but lighter than real activation
                rec.energy = (rec.energy + REPLAY_ENERGY).min(1.0);
            }
        }

        // Track co-activation pair appearances
        for i in 0..fp.activations.len() {
            for j in (i + 1)..fp.activations.len() {
                let a = fp.activations[i].0.min(fp.activations[j].0);
                let b = fp.activations[i].0.max(fp.activations[j].0);
                *pair_appearances.entry((a, b)).or_insert(0) += 1;
            }
        }
    }

    // Step 2: Strengthen frequently co-appearing pairs
    let mut strengthened = 0u32;
    for ((a, b), appearances) in &pair_appearances {
        if *appearances >= STRENGTHEN_MIN_APPEARANCES {
            if let Some(pair) = hebb.coactivations.get_mut(&(*a, *b)) {
                pair.count = (pair.count as f32 * STRENGTHEN_MULTIPLIER) as u32;
                strengthened += 1;
            }
        }
    }

    // Step 3: Prune weak co-activation pairs
    let mut pruned_pairs = 0u32;
    hebb.coactivations.retain(|_, pair| {
        if pair.count <= COACTIVATION_PRUNE_THRESHOLD && pair.last_ts_ms + PRUNE_AGE_MS < t0 {
            pruned_pairs += 1;
            false
        } else {
            true
        }
    });

    // Step 4: Prune cold activations
    let mut pruned_activations = 0u32;
    for rec in &mut hebb.activations {
        if rec.energy < ACTIVATION_PRUNE_ENERGY && rec.activation_count == 0 {
            *rec = crate::hebbian::ActivationRecord::default();
            pruned_activations += 1;
        }
    }

    // Step 5: Pattern detection
    let patterns_before = thought_graph.crystallized_count();
    thought_graph.detect_patterns();
    let consolidated_patterns = (thought_graph.crystallized_count() - patterns_before) as u32;

    // Step 6: Decay resonance field
    resonance.decay_field(FIELD_DREAM_DECAY);
    resonance.expire_pulses();

    // Step 7: Predictive cache cleanup — remove predictions with very low confidence
    pred_cache.dream_cleanup();

    // Measure energy after
    let energy_after: f32 = hebb.activations.iter().map(|r| r.energy).sum();

    // Save everything
    hebb.save(output_dir)
        .map_err(|e| format!("save hebbian: {}", e))?;
    thought_graph
        .save(output_dir)
        .map_err(|e| format!("save thought_graph: {}", e))?;
    pred_cache
        .save(output_dir)
        .map_err(|e| format!("save predictive_cache: {}", e))?;
    resonance
        .save(output_dir)
        .map_err(|e| format!("save resonance: {}", e))?;

    let duration_ms = (now_ms() - t0) as u32;

    Ok(DreamCycle {
        timestamp_ms: t0,
        duration_ms,
        replayed_fingerprints: replayed_count,
        strengthened_pairs: strengthened,
        pruned_pairs,
        pruned_activations,
        consolidated_patterns,
        energy_before,
        energy_after,
    })
}

// ─── Binary helpers ─────────────────────────────────

fn read_u32(b: &[u8], off: usize) -> u32 {
    u32::from_le_bytes(b[off..off + 4].try_into().unwrap())
}
fn read_u64(b: &[u8], off: usize) -> u64 {
    u64::from_le_bytes(b[off..off + 8].try_into().unwrap())
}
fn read_f32(b: &[u8], off: usize) -> f32 {
    f32::from_le_bytes(b[off..off + 4].try_into().unwrap())
}

fn now_ms() -> u64 {
    SystemTime::now()
        .duration_since(UNIX_EPOCH)
        .unwrap_or_default()
        .as_millis() as u64
}

// ─── Tests ──────────────────────────────────────────

#[cfg(test)]
mod tests {
    use super::*;
    use crate::archetype::ArchetypeState;
    use crate::hebbian::{ActivationFingerprint, ActivationRecord, CoactivationPair};
    use crate::predictive_cache::PredictiveCache;
    use crate::resonance::ResonanceState;
    use crate::thought_graph::ThoughtGraphState;
    use std::collections::HashMap;

    fn make_hebb(block_count: usize) -> HebbianState {
        HebbianState {
            activations: vec![ActivationRecord::default(); block_count],
            coactivations: HashMap::new(),
            fingerprints: Vec::new(),
        }
    }

    #[test]
    fn test_dream_log_roundtrip() {
        let tmp = tempfile::tempdir().expect("tempdir");
        let state = DreamState {
            cycles: vec![
                DreamCycle {
                    timestamp_ms: 1000,
                    duration_ms: 50,
                    replayed_fingerprints: 10,
                    strengthened_pairs: 3,
                    pruned_pairs: 5,
                    pruned_activations: 2,
                    consolidated_patterns: 1,
                    energy_before: 10.5,
                    energy_after: 8.2,
                },
                DreamCycle {
                    timestamp_ms: 2000,
                    duration_ms: 30,
                    replayed_fingerprints: 8,
                    strengthened_pairs: 2,
                    pruned_pairs: 3,
                    pruned_activations: 1,
                    consolidated_patterns: 0,
                    energy_before: 8.2,
                    energy_after: 7.0,
                },
            ],
            last_dream_ms: 2000,
        };
        state.save(tmp.path()).unwrap();
        let loaded = DreamState::load_or_init(tmp.path());
        assert_eq!(loaded.cycles.len(), 2);
        assert_eq!(loaded.last_dream_ms, 2000);
        assert_eq!(loaded.cycles[0].replayed_fingerprints, 10);
        assert_eq!(loaded.cycles[1].pruned_pairs, 3);
    }

    #[test]
    fn test_dream_strengthens_repeated_coactivations() {
        let tmp = tempfile::tempdir().expect("tempdir");
        let mut hebb = make_hebb(10);

        // Insert a co-activation pair
        hebb.coactivations.insert(
            (0, 1),
            CoactivationPair {
                block_a: 0,
                block_b: 1,
                count: 5,
                last_ts_ms: now_ms(),
            },
        );

        // Add 3 fingerprints that co-activate blocks 0 and 1
        let now = now_ms();
        for i in 0..3 {
            hebb.fingerprints.push(ActivationFingerprint {
                timestamp_ms: now - i * 1000,
                query_hash: 100 + i,
                activations: vec![(0, 0.5), (1, 0.3)],
            });
        }

        hebb.save(tmp.path()).unwrap();

        // Also need thought_graph, pred_cache, resonance, archetypes
        let tg = ThoughtGraphState::load_or_init(tmp.path());
        tg.save(tmp.path()).unwrap();
        let pc = PredictiveCache::load_or_init(tmp.path());
        pc.save(tmp.path()).unwrap();
        let res = ResonanceState::load_or_init(tmp.path());
        res.save(tmp.path()).unwrap();
        let arc = ArchetypeState::load_or_init(tmp.path());
        arc.save(tmp.path()).unwrap();

        let cycle = dream_consolidate(tmp.path(), 10).unwrap();
        assert!(cycle.strengthened_pairs > 0);

        // Verify the pair was strengthened
        let hebb2 = HebbianState::load_or_init(tmp.path(), 10);
        let pair = hebb2.coactivations.get(&(0, 1)).unwrap();
        assert!(pair.count > 5); // was 5, should be 5 * 1.5 = 7
    }

    #[test]
    fn test_dream_prunes_weak_pairs() {
        let tmp = tempfile::tempdir().expect("tempdir");
        let mut hebb = make_hebb(5);

        // Old, weak pair
        hebb.coactivations.insert(
            (0, 1),
            CoactivationPair {
                block_a: 0,
                block_b: 1,
                count: 1,
                last_ts_ms: 1000, // very old
            },
        );
        // Recent, strong pair
        hebb.coactivations.insert(
            (2, 3),
            CoactivationPair {
                block_a: 2,
                block_b: 3,
                count: 10,
                last_ts_ms: now_ms(),
            },
        );

        hebb.save(tmp.path()).unwrap();
        ThoughtGraphState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        PredictiveCache::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        ResonanceState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        ArchetypeState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();

        let cycle = dream_consolidate(tmp.path(), 5).unwrap();
        assert_eq!(cycle.pruned_pairs, 1);

        let hebb2 = HebbianState::load_or_init(tmp.path(), 5);
        assert!(!hebb2.coactivations.contains_key(&(0, 1))); // pruned
        assert!(hebb2.coactivations.contains_key(&(2, 3))); // kept
    }

    #[test]
    fn test_dream_replays_fingerprints() {
        let tmp = tempfile::tempdir().expect("tempdir");
        let mut hebb = make_hebb(5);

        // Block 0 has zero energy
        assert_eq!(hebb.activations[0].energy, 0.0);

        // Add a recent fingerprint activating block 0
        hebb.fingerprints.push(ActivationFingerprint {
            timestamp_ms: now_ms() - 1000,
            query_hash: 42,
            activations: vec![(0, 0.5)],
        });

        hebb.save(tmp.path()).unwrap();
        ThoughtGraphState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        PredictiveCache::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        ResonanceState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        ArchetypeState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();

        let cycle = dream_consolidate(tmp.path(), 5).unwrap();
        assert_eq!(cycle.replayed_fingerprints, 1);

        let hebb2 = HebbianState::load_or_init(tmp.path(), 5);
        assert!(hebb2.activations[0].energy >= REPLAY_ENERGY - 0.01);
    }

    #[test]
    fn test_dream_no_fingerprints() {
        let tmp = tempfile::tempdir().expect("tempdir");
        let hebb = make_hebb(5);
        hebb.save(tmp.path()).unwrap();
        ThoughtGraphState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        PredictiveCache::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        ResonanceState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();
        ArchetypeState::load_or_init(tmp.path())
            .save(tmp.path())
            .unwrap();

        let cycle = dream_consolidate(tmp.path(), 5).unwrap();
        assert_eq!(cycle.replayed_fingerprints, 0);
        assert_eq!(cycle.strengthened_pairs, 0);
        assert_eq!(cycle.pruned_pairs, 0);
    }

    #[test]
    fn test_dream_stats() {
        let state = DreamState {
            cycles: vec![
                DreamCycle {
                    timestamp_ms: 1000,
                    duration_ms: 50,
                    replayed_fingerprints: 10,
                    strengthened_pairs: 3,
                    pruned_pairs: 5,
                    pruned_activations: 2,
                    consolidated_patterns: 1,
                    energy_before: 10.0,
                    energy_after: 8.0,
                },
                DreamCycle {
                    timestamp_ms: 2000,
                    duration_ms: 30,
                    replayed_fingerprints: 8,
                    strengthened_pairs: 2,
                    pruned_pairs: 3,
                    pruned_activations: 1,
                    consolidated_patterns: 0,
                    energy_before: 8.0,
                    energy_after: 7.0,
                },
            ],
            last_dream_ms: 2000,
        };
        let stats = state.stats();
        assert_eq!(stats.total_cycles, 2);
        assert_eq!(stats.total_pruned_pairs, 8);
        assert_eq!(stats.total_strengthened, 5);
        assert_eq!(stats.total_replayed, 18);
    }
}