maple-runtime 0.1.1

//! Temporal coordination without global clocks
//!
//! The Resonance Architecture does NOT assume synchronized clocks.
//! Time is defined relationally through temporal anchors.

use dashmap::DashMap;
use std::sync::Arc;
use tokio::sync::RwLock;
use crate::types::*;
use crate::config::TemporalConfig as TemporalCoordinatorConfig;

/// Temporal Coordinator manages temporal relationships without global clocks
pub struct TemporalCoordinator {
    /// Per-Resonator local timelines
    timelines: DashMap<ResonatorId, LocalTimeline>,

    /// Causal graph derived from temporal anchors
    causality_graph: Arc<RwLock<CausalityGraph>>,

    /// Temporal anchor registry
    anchors: DashMap<AnchorId, TemporalAnchor>,

    /// Configuration
    config: TemporalCoordinatorConfig,
}

impl TemporalCoordinator {
    pub fn new(config: &TemporalCoordinatorConfig) -> Self {
        Self {
            timelines: DashMap::new(),
            causality_graph: Arc::new(RwLock::new(CausalityGraph::new())),
            anchors: DashMap::new(),
            config: config.clone(),
        }
    }

    /// Create a temporal anchor for an event
    ///
    /// This enables causal ordering without relying on global clocks.
    pub fn anchor(&self, event: &ResonanceEvent, resonator: ResonatorId) -> TemporalAnchor {
        // Get or create timeline for this Resonator
        let mut timeline = self
            .timelines
            .entry(resonator)
            .or_insert_with(|| LocalTimeline::new());

        let local_time = timeline.next_timestamp();

        let causal_deps = self.compute_causal_dependencies(event);

        let anchor = TemporalAnchor {
            id: AnchorId::generate(),
            local_time,
            causal_deps: causal_deps.clone(),
            commitment: event.commitment_id(),
        };

        // Register anchor
        self.anchors.insert(anchor.id, anchor.clone());

        // Add to causality graph
        // (would be done asynchronously in real implementation)

        tracing::trace!("Created temporal anchor {} for {}", anchor.id, resonator);

        anchor
    }

    /// Compute causal dependencies for an event
    fn compute_causal_dependencies(&self, event: &ResonanceEvent) -> Vec<AnchorId> {
        // Extract causal dependencies from event context
        // For now, placeholder
        event.causal_context().iter().copied().collect()
    }

    /// Determine causal ordering between events
    ///
    /// Returns None if events are concurrent (no causal relationship)
    pub fn causal_order(
        &self,
        a: &TemporalAnchor,
        b: &TemporalAnchor,
    ) -> Option<std::cmp::Ordering> {
        // Check if a happened-before b
        if self.happened_before(a, b) {
            return Some(std::cmp::Ordering::Less);
        }

        // Check if b happened-before a
        if self.happened_before(b, a) {
            return Some(std::cmp::Ordering::Greater);
        }

        // Concurrent (no causal relationship)
        None
    }

    /// Check if anchor 'a' happened-before anchor 'b'
    fn happened_before(&self, a: &TemporalAnchor, b: &TemporalAnchor) -> bool {
        // a happened-before b if:
        // 1. a is in b's causal dependencies, OR
        // 2. There exists c such that a happened-before c and c happened-before b

        if b.causal_deps.contains(&a.id) {
            return true;
        }

        // Check transitive dependencies (with cycle detection)
        // Simplified implementation - real version would use graph traversal
        for dep_id in &b.causal_deps {
            if let Some(dep) = self.anchors.get(dep_id) {
                if self.happened_before(a, &dep) {
                    return true;
                }
            }
        }

        false
    }

    /// Get an anchor by ID
    pub fn get_anchor(&self, id: &AnchorId) -> Option<TemporalAnchor> {
        self.anchors.get(id).map(|r| r.clone())
    }

    /// Check if two events are concurrent
    pub fn are_concurrent(&self, a: &TemporalAnchor, b: &TemporalAnchor) -> bool {
        self.causal_order(a, b).is_none()
    }
}

/// Local timeline for a Resonator
struct LocalTimeline {
    current_sequence: u64,
}

impl LocalTimeline {
    fn new() -> Self {
        Self {
            current_sequence: 0,
        }
    }

    fn next_timestamp(&mut self) -> LocalTimestamp {
        let seq = self.current_sequence;
        self.current_sequence += 1;
        LocalTimestamp::with_sequence(seq)
    }
}

/// Causality graph for detecting happened-before relationships
struct CausalityGraph {
    // Placeholder - in real implementation, would use a proper graph structure
}

impl CausalityGraph {
    fn new() -> Self {
        Self {}
    }
}

/// Resonance event for temporal anchoring
#[derive(Debug, Clone)]
pub struct ResonanceEvent {
    causal_context: Vec<AnchorId>,
    commitment: Option<CommitmentId>,
}

impl ResonanceEvent {
    pub fn new() -> Self {
        Self {
            causal_context: Vec::new(),
            commitment: None,
        }
    }

    pub fn with_causal_context(mut self, context: Vec<AnchorId>) -> Self {
        self.causal_context = context;
        self
    }

    pub fn with_commitment(mut self, commitment: CommitmentId) -> Self {
        self.commitment = Some(commitment);
        self
    }

    pub fn causal_context(&self) -> &[AnchorId] {
        &self.causal_context
    }

    pub fn commitment_id(&self) -> Option<CommitmentId> {
        self.commitment
    }
}

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