//! Health Snapshot — on-demand query for all subsystem health status
//!
//! Provides a single Tauri command that aggregates health data from:
//! - Intelligence Heartbeat engine (running state, config, alerts)
//! - Memory pipeline (entries count, storage size)
//!
//! Connection and SaaS status are managed by frontend stores and not included here.

use serde::Serialize;
use super::heartbeat::{HeartbeatConfig, HeartbeatEngineState, HeartbeatResult};

/// Aggregated health snapshot from Rust backend
#[derive(Debug, Serialize)]
#[serde(rename_all = "camelCase")]
pub struct HealthSnapshot {
    pub timestamp: String,
    pub intelligence: IntelligenceHealth,
    pub memory: MemoryHealth,
}

/// Intelligence heartbeat engine status
#[derive(Debug, Serialize)]
#[serde(rename_all = "camelCase")]
pub struct IntelligenceHealth {
    pub engine_running: bool,
    pub config: HeartbeatConfig,
    pub last_tick: Option<String>,
    pub alert_count_24h: usize,
    pub total_checks: usize,
}

/// Memory pipeline status
#[derive(Debug, Serialize)]
#[serde(rename_all = "camelCase")]
pub struct MemoryHealth {
    pub total_entries: usize,
    pub storage_size_bytes: u64,
    pub last_extraction: Option<String>,
}

/// Query a unified health snapshot for an agent
// @connected
#[tauri::command]
pub async fn health_snapshot(
    agent_id: String,
    heartbeat_state: tauri::State<'_, HeartbeatEngineState>,
) -> Result<HealthSnapshot, String> {
    let engines = heartbeat_state.lock().await;

    let engine = engines
        .get(&agent_id)
        .ok_or_else(|| format!("Heartbeat engine not initialized for agent: {}", agent_id))?;

    let engine_running = engine.is_running().await;
    let config = engine.get_config().await;
    let history: Vec<HeartbeatResult> = engine.get_history(100).await;

    // Calculate alert count in the last 24 hours
    let now = chrono::Utc::now();
    let twenty_four_hours_ago = now - chrono::Duration::hours(24);
    let alert_count_24h = history
        .iter()
        .filter(|r| {
            r.timestamp.parse::<chrono::DateTime<chrono::Utc>>()
                .map(|t| t > twenty_four_hours_ago)
                .unwrap_or(false)
        })
        .flat_map(|r| r.alerts.iter())
        .count();

    let last_tick = history.first().map(|r| r.timestamp.clone());

    // Memory health from cached stats (fallback to zeros)
    // Read cache in a separate scope to ensure RwLockReadGuard is dropped before any .await
    let cached_stats: Option<super::heartbeat::MemoryStatsCache> = {
        let cache = super::heartbeat::get_memory_stats_cache();
        match cache.read() {
            Ok(c) => c.get(&agent_id).cloned(),
            Err(_) => None,
        }
    }; // RwLockReadGuard dropped here

    let memory = match cached_stats {
        Some(s) => MemoryHealth {
            total_entries: s.total_entries,
            storage_size_bytes: s.storage_size_bytes as u64,
            last_extraction: s.last_updated,
        },
        None => {
            // Fallback: try to query VikingStorage directly
            match crate::viking_commands::get_storage().await {
                Ok(storage) => {
                    match zclaw_growth::VikingStorage::find_by_prefix(&*storage, &format!("mem:{}", agent_id)).await {
                        Ok(entries) => MemoryHealth {
                            total_entries: entries.len(),
                            storage_size_bytes: 0,
                            last_extraction: None,
                        },
                        Err(_) => MemoryHealth {
                            total_entries: 0,
                            storage_size_bytes: 0,
                            last_extraction: None,
                        },
                    }
                }
                Err(_) => MemoryHealth {
                    total_entries: 0,
                    storage_size_bytes: 0,
                    last_extraction: None,
                },
            }
        }
    };

    Ok(HealthSnapshot {
        timestamp: chrono::Utc::now().to_rfc3339(),
        intelligence: IntelligenceHealth {
            engine_running,
            config,
            last_tick,
            alert_count_24h,
            total_checks: 5, // Fixed: 5 built-in checks
        },
        memory,
    })
}