// unconscious.rs — Graph maintenance agents
//
// Standalone agents that operate on the memory graph without needing
// conversation context. Each agent runs in a loop: finish one run,
// start the next. Agents can be toggled on/off, persisted to
// ~/.consciousness/agent-enabled.json.

use std::time::Instant;
use std::collections::HashMap;
use futures::FutureExt;

use crate::agent::oneshot::{AutoAgent, AutoStep, RunStats};
use crate::agent::tools;
use crate::subconscious::defs;

fn config_path() -> std::path::PathBuf {
    dirs::home_dir().unwrap_or_default()
        .join(".consciousness/agent-enabled.json")
}

fn load_enabled_config() -> HashMap<String, bool> {
    std::fs::read_to_string(config_path()).ok()
        .and_then(|s| serde_json::from_str(&s).ok())
        .unwrap_or_default()
}

fn save_enabled_config(map: &HashMap<String, bool>) {
    if let Ok(json) = serde_json::to_string_pretty(map) {
        let _ = std::fs::write(config_path(), json);
    }
}

struct UnconsciousAgent {
    name: String,
    enabled: bool,
    auto: Option<AutoAgent>,
    handle: Option<tokio::task::JoinHandle<(AutoAgent, Result<(), String>)>>,
    /// Shared agent handle — UI locks to read context live.
    pub agent: Option<std::sync::Arc<crate::agent::Agent>>,
    last_run: Option<Instant>,
}

impl UnconsciousAgent {
    fn is_running(&self) -> bool {
        self.handle.as_ref().is_some_and(|h| !h.is_finished())
    }

    fn should_run(&self) -> bool {
        self.enabled && !self.is_running()
    }
}

/// Snapshot for the TUI.
#[derive(Clone)]
pub struct UnconsciousSnapshot {
    pub name: String,
    pub running: bool,
    pub enabled: bool,
    pub runs: usize,
    pub last_run_secs_ago: Option<f64>,
    pub agent: Option<std::sync::Arc<crate::agent::Agent>>,
    pub last_stats: Option<RunStats>,
    /// Recent store activity for this agent: (key, timestamp), newest first.
    pub history: Vec<(String, i64)>,
    pub tool_calls_ewma: f64,
    pub tool_failures_ewma: f64,
}

pub struct Unconscious {
    agents: Vec<UnconsciousAgent>,
    max_concurrent: usize,
    pub graph_health: Option<crate::subconscious::daemon::GraphHealth>,
    last_health_check: Option<Instant>,
    /// Notified when agent state changes (finished, toggled)
    pub wake: std::sync::Arc<tokio::sync::Notify>,
}

impl Unconscious {
    pub fn new() -> Self {
        let enabled_map = load_enabled_config();

        // Scan all .agent files, exclude subconscious-* and surface-observe
        let mut agents: Vec<UnconsciousAgent> = Vec::new();
        let base_tools = tools::memory::memory_tools().to_vec();
        let extra_tools = tools::memory::journal_tools().to_vec();
        for def in defs::load_defs() {
            if def.agent.starts_with("subconscious-") { continue; }
            if def.agent == "surface-observe" { continue; }
            let enabled = enabled_map.get(&def.agent).copied()
                .unwrap_or(false);
            let mut effective_tools = base_tools.clone();
            for name in &def.tools {
                if let Some(t) = extra_tools.iter().find(|t| t.name == name) {
                    effective_tools.push(t.clone());
                }
            }
            let steps: Vec<AutoStep> = def.steps.iter().map(|s| AutoStep {
                prompt: s.prompt.clone(),
                phase: s.phase.clone(),
            }).collect();
            let auto = AutoAgent::new(
                def.agent.clone(), effective_tools, steps,
                def.temperature.unwrap_or(0.6), def.priority,
            );
            agents.push(UnconsciousAgent {
                name: def.agent.clone(),
                enabled,
                auto: Some(auto),
                handle: None,
                agent: None,
                last_run: None,
            });
        }
        agents.sort_by(|a, b| a.name.cmp(&b.name));

        let max_concurrent = crate::config::get().llm_concurrency;

        Self {
            agents, max_concurrent,
            graph_health: None,
            last_health_check: None,
            wake: std::sync::Arc::new(tokio::sync::Notify::new()),
        }
    }

    /// Toggle an agent on/off by name. Returns new enabled state.
    /// If enabling, immediately spawns the agent if it's not running.
    pub async fn toggle(&mut self, name: &str) -> Option<bool> {
        let idx = self.agents.iter().position(|a| a.name == name)?;
        self.agents[idx].enabled = !self.agents[idx].enabled;
        let new_state = self.agents[idx].enabled;
        self.save_enabled();
        if new_state && !self.agents[idx].is_running() && self.agents[idx].auto.is_some() {
            let agent_name = self.agents[idx].name.clone();
            let auto = self.agents[idx].auto.take().unwrap();
            let wake = self.wake.clone();
            match prepare_spawn(&agent_name, auto, wake).await {
                Ok(result) => self.complete_spawn(idx, result),
                Err(auto) => self.abort_spawn(idx, auto),
            }
        }
        self.wake.notify_one(); // wake loop to consider new state
        Some(new_state)
    }

    fn save_enabled(&self) {
        let map: HashMap<String, bool> = self.agents.iter()
            .map(|a| (a.name.clone(), a.enabled))
            .collect();
        save_enabled_config(&map);
    }

    pub fn snapshots(&self, store: Option<&crate::store::Store>) -> Vec<UnconsciousSnapshot> {
        self.agents.iter().map(|a| {
            let history = store.map(|st| st.recent_by_provenance(&a.name, 30))
                .unwrap_or_default();
            let stats = crate::agent::oneshot::get_stats(&a.name);
            let tool_calls_ewma: f64 = stats.by_tool.values().map(|t| t.ewma).sum();
            UnconsciousSnapshot {
                name: a.name.clone(),
                running: a.is_running(),
                enabled: a.enabled,
                runs: stats.runs,
                last_run_secs_ago: a.last_run.map(|t| t.elapsed().as_secs_f64()),
                agent: a.agent.clone(),
                last_stats: stats.last_stats.clone(),
                history,
                tool_calls_ewma,
                tool_failures_ewma: stats.failures.ewma,
            }
        }).collect()
    }

    /// Check if health refresh is due (quick check, no I/O).
    pub fn needs_health_refresh(&self) -> bool {
        self.last_health_check
            .map(|t| t.elapsed() > std::time::Duration::from_secs(600))
            .unwrap_or(true)
    }

    /// Store computed health (quick, just assignment).
    pub fn set_health(&mut self, health: crate::subconscious::daemon::GraphHealth) {
        self.graph_health = Some(health);
        self.last_health_check = Some(Instant::now());
    }

    /// Reap finished agents (quick, hold lock briefly).
    pub fn reap_finished(&mut self) {
        for agent in &mut self.agents {
            if agent.handle.as_ref().is_some_and(|h| h.is_finished()) {
                let handle = agent.handle.take().unwrap();
                agent.last_run = Some(Instant::now());
                // Get the AutoAgent back from the finished task (stats already updated)
                match handle.now_or_never() {
                    Some(Ok((auto_back, result))) => {
                        agent.auto = Some(auto_back);
                        match result {
                            Ok(_) => dbglog!("[unconscious] {} completed (run {})",
                                agent.name, crate::agent::oneshot::get_stats(&agent.name).runs),
                            Err(e) => dbglog!("[unconscious] {} failed: {}", agent.name, e),
                        }
                    }
                    _ => dbglog!("[unconscious] {} task lost", agent.name),
                }
            }
        }
    }

    /// Select agents to spawn and take their AutoAgents out (quick, hold lock briefly).
    /// Returns vec of (index, name, auto, tools) for agents that should spawn.
    pub fn select_to_spawn(&mut self) -> Vec<(usize, String, AutoAgent)> {
        let running = self.agents.iter().filter(|a| a.is_running()).count();
        let mut to_spawn = Vec::new();

        for _ in running..self.max_concurrent {
            let next = self.agents.iter().enumerate()
                .filter(|(_, a)| a.should_run() && a.auto.is_some())
                .min_by_key(|(_, a)| a.last_run);
            match next {
                Some((idx, _)) => {
                    let name = self.agents[idx].name.clone();
                    let auto = self.agents[idx].auto.take().unwrap();
                    to_spawn.push((idx, name, auto));
                }
                None => break,
            }
        }
        to_spawn
    }

    /// Store spawn result back (quick, hold lock briefly).
    pub fn complete_spawn(&mut self, idx: usize, result: SpawnResult) {
        self.agents[idx].agent = Some(result.agent);
        self.agents[idx].handle = Some(result.handle);
    }

    /// Restore auto on spawn failure (quick, hold lock briefly).
    pub fn abort_spawn(&mut self, idx: usize, auto: AutoAgent) {
        self.agents[idx].auto = Some(auto);
    }
}

/// Result of preparing an agent spawn (created outside the lock).
pub struct SpawnResult {
    pub agent: std::sync::Arc<crate::agent::Agent>,
    pub handle: tokio::task::JoinHandle<(AutoAgent, Result<(), String>)>,
}

/// Prepare an agent spawn — does the slow work (Store::load, query, Agent::new).
/// Called outside the Unconscious lock.
/// On success, auto is consumed (moved into spawned task).
/// On failure, auto is returned so it can be restored.
pub async fn prepare_spawn(name: &str, mut auto: AutoAgent, wake: std::sync::Arc<tokio::sync::Notify>) -> Result<SpawnResult, AutoAgent> {
    dbglog!("[unconscious] spawning {}", name);

    let def = match defs::get_def(name) {
        Some(d) => d,
        None => return Err(auto),
    };

    let exclude: std::collections::HashSet<String> = std::collections::HashSet::new();
    let batch = match defs::run_agent(
        &def, def.count.unwrap_or(5), &exclude,
    ).await {
        Ok(b) => b,
        Err(e) => {
            dbglog!("[unconscious] {} query failed: {}", name, e);
            return Err(auto);
        }
    };

    let orig_steps = std::mem::replace(&mut auto.steps,
        batch.steps.iter().map(|s| AutoStep {
            prompt: s.prompt.clone(),
            phase: s.phase.clone(),
        }).collect());

    // Create standalone Agent — stored so UI can read context
    let config = crate::config::get();
    let base_url = config.api_base_url.as_deref().unwrap_or("");
    let api_key = config.api_key.as_deref().unwrap_or("");
    let model = config.api_model.as_deref().unwrap_or("");
    if base_url.is_empty() || model.is_empty() {
        dbglog!("[unconscious] API not configured");
        auto.steps = orig_steps;
        return Err(auto);
    }

    let cli = crate::user::CliArgs::default();
    let (app, _) = match crate::config::load_app(&cli) {
        Ok(r) => r,
        Err(e) => {
            dbglog!("[unconscious] config: {}", e);
            auto.steps = orig_steps;
            return Err(auto);
        }
    };

    // Unconscious agents have self-contained prompts — no standard context.
    let client = crate::agent::api::ApiClient::new(base_url, api_key, model);
    let agent = crate::agent::Agent::new(
        client, Vec::new(),
        app, String::new(), None,
        crate::agent::tools::ActiveTools::new(),
        auto.tools.clone(),
    ).await;
    {
        let mut st = agent.state.lock().await;
        st.provenance = auto.name.clone();
        st.priority = Some(auto.priority);
        st.temperature = auto.temperature;
    }

    let agent_clone = agent.clone();
    let handle = tokio::spawn(async move {
        let result = auto.run_shared(&agent_clone).await;
        let stats = crate::agent::oneshot::save_agent_log(&auto.name, &agent_clone).await;
        auto.update_stats(stats);
        auto.steps = orig_steps;
        wake.notify_one(); // wake the loop to reap and maybe spawn more
        (auto, result)
    });

    Ok(SpawnResult { agent, handle })
}

// Backwards compat: trigger() that does all three phases (still holds lock too long, but works)
impl Unconscious {
    pub async fn trigger(&mut self) {
        self.reap_finished();
        let to_spawn = self.select_to_spawn();
        let wake = self.wake.clone();
        for (idx, name, auto) in to_spawn {
            match prepare_spawn(&name, auto, wake.clone()).await {
                Ok(result) => self.complete_spawn(idx, result),
                Err(auto) => self.abort_spawn(idx, auto),
            }
        }
    }
}

// save_agent_log and RunStats moved to crate::agent::oneshot