lean-ctx 3.5.21

//! RAM cleanup profile and memory-footprint presets (`config.toml`).

use serde::{Deserialize, Serialize};

use super::Config;

/// Controls how aggressively lean-ctx frees memory when idle.
/// - `aggressive`: (Default) Cache cleared after short idle period (5 min). Best for single-IDE use.
/// - `shared`: Cache retained longer (30 min). Best when multiple IDEs/models share lean-ctx context.
#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq)]
#[serde(rename_all = "lowercase")]
pub enum MemoryCleanup {
    #[default]
    Aggressive,
    Shared,
}

impl MemoryCleanup {
    pub fn from_env() -> Option<Self> {
        std::env::var("LEAN_CTX_MEMORY_CLEANUP").ok().and_then(|v| {
            match v.trim().to_lowercase().as_str() {
                "aggressive" => Some(Self::Aggressive),
                "shared" => Some(Self::Shared),
                _ => None,
            }
        })
    }

    pub fn effective(config: &Config) -> Self {
        if let Some(env_val) = Self::from_env() {
            return env_val;
        }
        config.memory_cleanup.clone()
    }

    /// Idle TTL in seconds before cache is auto-cleared.
    pub fn idle_ttl_secs(&self) -> u64 {
        match self {
            Self::Aggressive => 300,
            Self::Shared => 1800,
        }
    }

    /// BM25 index eviction age multiplier (shared mode retains longer).
    pub fn index_retention_multiplier(&self) -> f64 {
        match self {
            Self::Aggressive => 1.0,
            Self::Shared => 3.0,
        }
    }
}

/// Controls RAM usage vs. feature richness trade-off.
/// - `low`: Minimal RAM footprint, disables optional caches and embedding features
/// - `balanced`: Default — moderate caches, single embedding engine
/// - `performance`: Maximum caches, all features enabled
#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq)]
#[serde(rename_all = "lowercase")]
pub enum MemoryProfile {
    Low,
    #[default]
    Balanced,
    Performance,
}

impl MemoryProfile {
    pub fn from_env() -> Option<Self> {
        std::env::var("LEAN_CTX_MEMORY_PROFILE").ok().and_then(|v| {
            match v.trim().to_lowercase().as_str() {
                "low" => Some(Self::Low),
                "balanced" => Some(Self::Balanced),
                "performance" => Some(Self::Performance),
                _ => None,
            }
        })
    }

    pub fn effective(config: &Config) -> Self {
        if let Some(env_val) = Self::from_env() {
            return env_val;
        }
        config.memory_profile.clone()
    }

    pub fn bm25_max_cache_mb(&self) -> u64 {
        match self {
            Self::Low => 64,
            Self::Balanced => 128,
            Self::Performance => 512,
        }
    }

    pub fn semantic_cache_enabled(&self) -> bool {
        !matches!(self, Self::Low)
    }

    pub fn embeddings_enabled(&self) -> bool {
        !matches!(self, Self::Low)
    }
}