lean-ctx 3.9.18

//! Shared adapter helpers for generalized cross-agent delivery caching.

use std::sync::OnceLock;
use std::time::{Duration, SystemTime, UNIX_EPOCH};

use super::cache_coordinator::{BuiltinCacheCoordinator, CacheCoordinator};
use super::cache_tiers::{L1ProcessCache, L2DaemonCache, L3DiskCache};
use super::cache_types::{
    AgentHost, CacheIdentity, CacheKey, CacheValidator, ContentHandleRef, DeliveryEntryV2,
    DeliveryKind,
};

static COORDINATOR: OnceLock<Option<BuiltinCacheCoordinator>> = OnceLock::new();

/// Returns the process-wide generalized delivery coordinator when caching is enabled.
pub fn coordinator() -> Option<&'static BuiltinCacheCoordinator> {
    COORDINATOR
        .get_or_init(|| {
            let config = crate::core::config::Config::load();
            if !config.ocla.delivery_enabled() {
                return None;
            }
            let root = crate::core::paths::cache_dir().ok()?.join("delivery-v2");
            let ttl = Duration::from_secs(config.ocla.delivery.ttl_minutes.saturating_mul(60));
            let l3 = L3DiskCache::open(root).ok()?;
            Some(BuiltinCacheCoordinator::new(
                L1ProcessCache::new(ttl),
                L2DaemonCache::new(config.ocla.delivery.max_entries, ttl),
                l3,
            ))
        })
        .as_ref()
}

/// Looks up an adapter result across all tiers including cross-process daemon.
pub fn check(key: &CacheKey, validator: &CacheValidator, adapter: &str) -> Option<DeliveryEntryV2> {
    let coordinator = coordinator()?;
    // L1 + local L2 + L3 (in-process)
    if let Some(entry) = coordinator.check(key, validator) {
        emit_stats(coordinator, adapter);
        return Some(entry);
    }
    // Cross-process: ask daemon (other processes may have recorded this)
    let agent = agent_id();
    let conv_id =
        crate::core::conversation::current_conversation_id().unwrap_or_else(|| agent.clone());
    if let Some(entry) =
        crate::daemon_client::try_cache_check_blocking(key, validator, Some(&agent), Some(&conv_id))
    {
        // Promote to L1 so subsequent calls skip IPC
        coordinator.record(entry.clone());
        emit_stats(coordinator, adapter);
        return Some(entry);
    }
    emit_stats(coordinator, adapter);
    None
}

/// Records an adapter result and emits the coordinator snapshot for observability.
pub fn record(
    key: CacheKey,
    kind: DeliveryKind,
    validator: CacheValidator,
    display_path: Option<String>,
    content: &str,
    adapter: &str,
) {
    let Some(coordinator) = coordinator() else {
        return;
    };
    let now = epoch_ms();
    let ttl_ms = crate::core::config::Config::load()
        .ocla
        .delivery
        .ttl_minutes
        .saturating_mul(60_000);
    let digest = blake3::hash(content.as_bytes()).to_hex().to_string();
    let agent_id = agent_id();
    let entry = DeliveryEntryV2 {
        schema_version: 2,
        key,
        kind,
        validator,
        handle: ContentHandleRef {
            algorithm: "blake3".into(),
            digest,
            byte_len: content.len() as u64,
            media_type: "text/plain".into(),
        },
        display_path,
        line_count: Some(content.lines().count() as u32),
        token_count: crate::core::tokens::count_tokens(content) as u64,
        producer: CacheIdentity {
            conversation_id: agent_id.clone(),
            agent_id,
            host: agent_host(),
        },
        created_at_epoch_ms: now,
        expires_at_epoch_ms: now.saturating_add(ttl_ms),
    };
    coordinator.record(entry.clone());
    crate::daemon_client::try_cache_record_blocking(&entry);
    emit_stats(coordinator, adapter);
}

/// Renders a deterministic reference in place of an already materialized result.
pub fn stub(entry: &DeliveryEntryV2, label: &str) -> String {
    let path = entry.display_path.as_deref().unwrap_or("result");
    format!(
        "{path} [cross-agent cache · {label} · produced by {} · {} tokens avoided]",
        entry.producer.agent_id, entry.token_count
    )
}

fn emit_stats(coordinator: &BuiltinCacheCoordinator, adapter: &str) {
    let stats = coordinator.stats();
    tracing::debug!(
        target: "lean_ctx::cache_delivery",
        adapter,
        l1_hits = stats.l1_hits,
        l2_hits = stats.l2_hits,
        l3_hits = stats.l3_hits,
        misses = stats.misses,
        materializations = stats.materializations,
        references_served = stats.references_served,
        tokens_saved = stats.tokens_saved,
        "cache coordinator stats"
    );
}

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

fn agent_id() -> String {
    std::env::var("CURSOR_TASK_ID")
        .or_else(|_| std::env::var("CLAUDECODE"))
        .or_else(|_| std::env::var("CODEX_THREAD_ID"))
        .unwrap_or_else(|_| "local-agent".into())
}

fn agent_host() -> AgentHost {
    if std::env::var_os("CURSOR_TASK_ID").is_some() {
        AgentHost::Cursor
    } else if std::env::var_os("CLAUDECODE").is_some() {
        AgentHost::ClaudeCode
    } else if std::env::var_os("CODEX_THREAD_ID").is_some() {
        AgentHost::Codex
    } else {
        AgentHost::Cli
    }
}