// oneshot.rs — Autonomous agent execution
//
// AutoAgent: wraps an Agent with a multi-step prompt sequence and an
// async run() method. Used for both oneshot CLI agents (from .agent
// files) and subconscious agents forked from the conscious agent.
//
// Also contains the legacy run_one_agent() pipeline and process
// management for spawned agent subprocesses.

use crate::store::{self, Store};
use crate::subconscious::{defs, prompts};

use std::collections::HashMap;
use std::fs;
use std::path::PathBuf;

use super::context::AstNode;
use super::tools::{self as agent_tools};
use super::Agent;

// ---------------------------------------------------------------------------
// Agent logging — shared by Mind and CLI paths
// ---------------------------------------------------------------------------

/// Stats from a single run.
#[derive(Clone, Default, serde::Serialize, serde::Deserialize)]
pub struct RunStats {
    pub messages: usize,
    pub tool_calls: usize,
    pub tool_failures: usize,
    pub tool_calls_by_type: HashMap<String, usize>,
}

/// Per-tool accumulated stats.
#[derive(Clone, Default, serde::Serialize, serde::Deserialize)]
pub struct ToolStats {
    pub last: usize,
    pub ewma: f64,
    pub total: usize,
}

/// Persisted stats for an agent (survives restarts).
#[derive(Clone, Default, serde::Serialize, serde::Deserialize)]
pub struct PersistedStats {
    pub runs: usize,
    pub last_stats: Option<RunStats>,
    /// Per-tool-type stats: last, ewma, total.
    pub by_tool: HashMap<String, ToolStats>,
    /// Failed calls stats.
    pub failures: ToolStats,
}

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

static AGENT_STATS: std::sync::OnceLock<std::sync::Mutex<HashMap<String, PersistedStats>>> =
    std::sync::OnceLock::new();

fn stats_map() -> &'static std::sync::Mutex<HashMap<String, PersistedStats>> {
    AGENT_STATS.get_or_init(|| {
        let map: HashMap<String, PersistedStats> = std::fs::read_to_string(stats_path()).ok()
            .and_then(|s| serde_json::from_str(&s).ok())
            .unwrap_or_default();
        std::sync::Mutex::new(map)
    })
}

pub fn get_stats(name: &str) -> PersistedStats {
    stats_map().lock().ok()
        .and_then(|m| m.get(name).cloned())
        .unwrap_or_default()
}

pub fn set_stats(name: &str, stats: PersistedStats) {
    if let Ok(mut map) = stats_map().lock() {
        map.insert(name.to_string(), stats);
        if let Ok(json) = serde_json::to_string_pretty(&*map) {
            let _ = std::fs::write(stats_path(), json);
        }
    }
}

/// Save agent conversation to JSON log file.
/// Used by both mind-run agents and CLI-run agents.
pub async fn save_agent_log(name: &str, agent: &std::sync::Arc<Agent>) -> RunStats {
    let dir = dirs::home_dir().unwrap_or_default()
        .join(format!(".consciousness/logs/{}", name));
    let ctx = agent.context.lock().await;
    let stats = compute_run_stats(ctx.conversation());
    if std::fs::create_dir_all(&dir).is_ok() {
        let ts = chrono::Utc::now().format("%Y%m%d-%H%M%S");
        let path = dir.join(format!("{}.json", ts));
        let mut context: Vec<&super::context::AstNode> = Vec::new();
        for section in ctx.sections() {
            context.extend(section);
        }
        if let Ok(json) = serde_json::to_string_pretty(&context) {
            let _ = std::fs::write(&path, json);
        }
    }
    dbglog!("[agent] {} — {} msgs, {} tool calls",
        name, stats.messages, stats.tool_calls);
    stats
}

fn compute_run_stats(conversation: &[super::context::AstNode]) -> RunStats {
    use super::context::{AstNode, NodeBody};

    let mut messages = 0usize;
    let mut tool_calls = 0usize;
    let mut tool_failures = 0usize;
    let mut by_type: HashMap<String, usize> = HashMap::new();

    for node in conversation {
        if let AstNode::Branch { children, .. } = node {
            messages += 1;
            for child in children {
                if let AstNode::Leaf(leaf) = child {
                    match leaf.body() {
                        NodeBody::ToolCall { name, .. } => {
                            tool_calls += 1;
                            *by_type.entry(name.to_string()).or_default() += 1;
                        }
                        NodeBody::ToolResult(text) => {
                            // Detect failures from error patterns in result
                            let t = text.trim_start();
                            if t.starts_with("Error") || t.starts_with("error:") ||
                               t.starts_with("Failed") || t.contains("not found") {
                                tool_failures += 1;
                            }
                        }
                        _ => {}
                    }
                }
            }
        }
    }

    RunStats { messages, tool_calls, tool_failures, tool_calls_by_type: by_type }
}

// ---------------------------------------------------------------------------
// AutoAgent — multi-step autonomous agent
// ---------------------------------------------------------------------------

pub struct AutoStep {
    pub prompt: String,
    pub phase: String,
}

/// An autonomous agent that runs a sequence of prompts with tool dispatch.
///
/// Persistent across runs — holds config, tools, steps, and inter-run
/// state (walked keys). The conversation backend is ephemeral per run.
pub struct AutoAgent {
    pub name: String,
    pub tools: Vec<agent_tools::Tool>,
    pub steps: Vec<AutoStep>,
    pub current_phase: String,
    pub turn: usize,
    pub enabled: bool,
    pub temperature: f32,
    pub priority: i32,
}


/// Per-run conversation backend — wraps a forked agent.
struct Backend(std::sync::Arc<Agent>);

impl Backend {
    async fn push_node(&mut self, node: AstNode) {
        self.0.push_node(node).await;
    }
}

/// Resolve {{placeholder}} templates in subconscious agent prompts.
fn resolve_prompt(
    template: &str,
    memory_keys: &[String],
    state: &std::collections::BTreeMap<String, String>,
    recently_written: &[String],
) -> String {
    let cfg = crate::config::get();
    let template = template.replace("{assistant_name}", &cfg.assistant_name);
    let mut result = String::with_capacity(template.len());
    let mut rest = template.as_str();
    while let Some(start) = rest.find("{{") {
        result.push_str(&rest[..start]);
        let after = &rest[start + 2..];
        if let Some(end) = after.find("}}") {
            let name = after[..end].trim();
            let replacement = if let Some(key) = name.strip_prefix("state:") {
                state.get(key).cloned().unwrap_or_else(|| "(not set)".to_string())
            } else {
                match name {
                    "seen_current" => format_key_list(memory_keys),
                    "recently_written" => format_key_list(recently_written),
                    _ => {
                        result.push_str("{{");
                        result.push_str(&after[..end + 2]);
                        rest = &after[end + 2..];
                        continue;
                    }
                }
            };
            result.push_str(&replacement);
            rest = &after[end + 2..];
        } else {
            result.push_str("{{");
            rest = after;
        }
    }
    result.push_str(rest);
    result
}



fn format_key_list(keys: &[String]) -> String {
    if keys.is_empty() { "(none)".to_string() }
    else { keys.iter().map(|k| format!("- {}", k)).collect::<Vec<_>>().join("\n") }
}

impl AutoAgent {
    pub fn new(
        name: String,
        tools: Vec<agent_tools::Tool>,
        steps: Vec<AutoStep>,
        temperature: f32,
        priority: i32,
    ) -> Self {
        Self {
            name, tools, steps,
            current_phase: String::new(),
            turn: 0,
            enabled: true,
            temperature,
            priority,
        }
    }

    pub async fn run(
        &mut self,
        bail_fn: Option<&(dyn Fn(usize) -> Result<(), String> + Sync)>,
    ) -> Result<(), String> {
        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() {
            return Err("API not configured (no base_url or model)".to_string());
        }
        let client = super::api::ApiClient::new(base_url, api_key, model);

        // Load system prompt + identity from config
        let cli = crate::user::CliArgs::default();
        let (app, _) = crate::config::load_app(&cli)
            .map_err(|e| format!("config: {}", e))?;
        let personality = crate::config::reload_for_model(
            &app, &app.prompts.other,
        ).await.map_err(|e| format!("config: {}", e))?;

        let agent = Agent::new(
            client, personality,
            app, String::new(),
            None,
            super::tools::ActiveTools::new(),
            super::tools::tools(),
        ).await;
        {
            let mut st = agent.state.lock().await;
            st.provenance = format!("standalone:{}", self.name);
            st.tools = self.tools.clone();
            st.temperature = self.temperature;
            st.priority = Some(self.priority);
        }

        let mut backend = Backend(agent.clone());
        let result = self.run_with_backend(&mut backend, bail_fn).await;
        save_agent_log(&self.name, &agent).await;
        result
    }

    /// Run using a pre-created agent Arc. The caller retains the Arc
    /// so the UI can lock it to read entries live.
    pub async fn run_shared(
        &mut self,
        agent: &std::sync::Arc<Agent>,
    ) -> Result<(), String> {
        let mut backend = Backend(agent.clone());
        self.run_with_backend(&mut backend, None).await
    }

    /// Run forked using a shared agent Arc. The UI can lock the same
    /// Arc to read entries live during the run.
    pub async fn run_forked_shared(
        &mut self,
        agent: &std::sync::Arc<Agent>,
        memory_keys: &[String],
        state: &std::collections::BTreeMap<String, String>,
        recently_written: &[String],
    ) -> Result<(), String> {
        let resolved_steps: Vec<AutoStep> = self.steps.iter().map(|s| AutoStep {
            prompt: resolve_prompt(&s.prompt, memory_keys, state, recently_written),
            phase: s.phase.clone(),
        }).collect();
        let orig_steps = std::mem::replace(&mut self.steps, resolved_steps);
        let mut backend = Backend(agent.clone());
        let result = self.run_with_backend(&mut backend, None).await;
        self.steps = orig_steps;
        result
    }

    /// Update stats after a run completes. Called with the stats from save_agent_log.
    pub fn update_stats(&self, run_stats: RunStats) {
        const ALPHA: f64 = 0.3;
        let old = get_stats(&self.name);

        // Update per-tool stats
        let mut by_tool = old.by_tool;
        for (tool, count) in &run_stats.tool_calls_by_type {
            let entry = by_tool.entry(tool.clone()).or_default();
            entry.last = *count;
            entry.ewma = ALPHA * (*count as f64) + (1.0 - ALPHA) * entry.ewma;
            entry.total += count;
        }

        // Update failure stats
        let failures = ToolStats {
            last: run_stats.tool_failures,
            ewma: ALPHA * (run_stats.tool_failures as f64) + (1.0 - ALPHA) * old.failures.ewma,
            total: old.failures.total + run_stats.tool_failures,
        };

        let new = PersistedStats {
            runs: old.runs + 1,
            last_stats: Some(run_stats),
            by_tool,
            failures,
        };
        set_stats(&self.name, new);
    }

    async fn run_with_backend(
        &mut self,
        backend: &mut Backend,
        bail_fn: Option<&(dyn Fn(usize) -> Result<(), String> + Sync)>,
    ) -> Result<(), String> {
        dbglog!("[auto] {} starting, {} steps", self.name, self.steps.len());

        for (i, step) in self.steps.iter().enumerate() {
            self.turn = i + 1;
            self.current_phase = step.phase.clone();

            if let Some(ref check) = bail_fn {
                check(i)?;
            }

            backend.push_node(AstNode::system_msg(&step.prompt)).await;
            Agent::turn(backend.0.clone()).await
                .map_err(|e| format!("{}: {}", self.name, e))?;
        }

        Ok(())
    }

}

// ---------------------------------------------------------------------------
// Agent execution
// ---------------------------------------------------------------------------

/// Result of running a single agent.
pub struct AgentResult {
    pub node_keys: Vec<String>,
    /// Directory containing output() files from the agent run.
    pub state_dir: PathBuf,
}

/// Run an agent. If keys are provided, use them directly (bypassing the
/// agent's query). Otherwise, run the query to select target nodes.
pub async fn run_one_agent(
    store: &mut Store,
    agent_name: &str,
    count: usize,
    keys: Option<&[String]>,
) -> Result<AgentResult, String> {
    let def = defs::get_def(agent_name)
        .ok_or_else(|| format!("no .agent file for {}", agent_name))?;

    // State dir for agent output files
    let state_dir = std::env::var("POC_AGENT_OUTPUT_DIR")
        .map(PathBuf::from)
        .unwrap_or_else(|_| store::memory_dir().join("agent-output").join(agent_name));
    fs::create_dir_all(&state_dir)
        .map_err(|e| format!("create state dir: {}", e))?;
    unsafe { std::env::set_var("POC_AGENT_OUTPUT_DIR", &state_dir); }

    // Build prompt batch — either from explicit keys or the agent's query
    let agent_batch = if let Some(keys) = keys {
        dbglog!("[{}] targeting: {}", agent_name, keys.join(", "));
        let mut resolved_steps = Vec::new();
        let mut all_keys: Vec<String> = keys.to_vec();
        for step in &def.steps {
            let (prompt, extra_keys) = defs::resolve_placeholders(
                &step.prompt, keys, count,
            ).await;
            all_keys.extend(extra_keys);
            resolved_steps.push(prompts::ResolvedStep {
                prompt,
                phase: step.phase.clone(),
            });
        }
        let batch = prompts::AgentBatch { steps: resolved_steps, node_keys: all_keys };
        if !batch.node_keys.is_empty() {
            store.record_agent_visits(&batch.node_keys, agent_name).ok();
        }
        batch
    } else {
        let effective_count = def.count.unwrap_or(count);
        defs::run_agent(&def, effective_count, &Default::default()).await?
    };

    // Base memory tools + extras from agent def (matching unconscious.rs pattern)
    let base_tools = super::tools::memory::memory_tools().to_vec();
    let extra_tools = super::tools::memory::journal_tools().to_vec();
    let mut effective_tools: Vec<super::tools::Tool> = if def.tools.is_empty() {
        let mut all = base_tools;
        all.extend(extra_tools);
        all
    } else {
        let mut tools = base_tools;
        for name in &def.tools {
            if let Some(t) = extra_tools.iter().find(|t| t.name == *name) {
                tools.push(t.clone());
            }
        }
        tools
    };
    effective_tools.push(super::tools::Tool {
        name: "output",
        description: "Produce a named output value for passing between steps.",
        parameters_json: r#"{"type":"object","properties":{"key":{"type":"string","description":"Output name"},"value":{"type":"string","description":"Output value"}},"required":["key","value"]}"#,
        handler: std::sync::Arc::new(|_agent, v| Box::pin(async move {
            let key = v["key"].as_str()
                .ok_or_else(|| anyhow::anyhow!("output requires 'key'"))?;
            if key.starts_with("pid-") || key.contains('/') || key.contains("..") {
                anyhow::bail!("invalid output key: {}", key);
            }
            let value = v["value"].as_str()
                .ok_or_else(|| anyhow::anyhow!("output requires 'value'"))?;
            let dir = std::env::var("POC_AGENT_OUTPUT_DIR")
                .map_err(|_| anyhow::anyhow!("no output directory set"))?;
            let path = std::path::Path::new(&dir).join(key);
            std::fs::write(&path, value)
                .map_err(|e| anyhow::anyhow!("writing output {}: {}", path.display(), e))?;
            Ok(format!("{}: {}", key, value))
        })),
    });
    let n_steps = agent_batch.steps.len();

    // Guard: reject oversized first prompt
    let max_prompt_bytes = 800_000;
    let first_len = agent_batch.steps[0].prompt.len();
    if first_len > max_prompt_bytes {
        let prompt_kb = first_len / 1024;
        let oversize_dir = store::memory_dir().join("llm-logs").join("oversized");
        fs::create_dir_all(&oversize_dir).ok();
        let oversize_path = oversize_dir.join(format!("{}-{}.txt",
            agent_name, store::compact_timestamp()));
        let header = format!("=== OVERSIZED PROMPT ===\nagent: {}\nsize: {}KB (max {}KB)\nnodes: {:?}\n\n",
            agent_name, prompt_kb, max_prompt_bytes / 1024, agent_batch.node_keys);
        fs::write(&oversize_path, format!("{}{}", header, &agent_batch.steps[0].prompt)).ok();
        return Err(format!(
            "prompt too large: {}KB (max {}KB) — seed nodes may be oversized",
            prompt_kb, max_prompt_bytes / 1024,
        ));
    }

    let phases: Vec<&str> = agent_batch.steps.iter().map(|s| s.phase.as_str()).collect();
    dbglog!("[{}] {} step(s) {:?}, {}KB initial, {} nodes",
        agent_name, n_steps, phases, first_len / 1024, agent_batch.node_keys.len());

    let prompts: Vec<String> = agent_batch.steps.iter()
        .map(|s| s.prompt.clone()).collect();
    let step_phases: Vec<String> = agent_batch.steps.iter()
        .map(|s| s.phase.clone()).collect();

    // Bail check: if the agent defines a bail script, run it between steps.
    let bail_script = def.bail.as_ref().map(|name| defs::agents_dir().join(name));
    let state_dir_for_bail = state_dir.clone();
    // Find our own pid file so we can pass it to the bail script
    let our_pid = std::process::id();
    let our_pid_file = format!("pid-{}", our_pid);
    let bail_fn = move |step_idx: usize| -> Result<(), String> {
        if let Some(ref script) = bail_script {
            let status = std::process::Command::new(script)
                .arg(&our_pid_file)
                .current_dir(&state_dir_for_bail)
                .status()
                .map_err(|e| format!("bail script {:?} failed: {}", script, e))?;
            if !status.success() {
                return Err(format!("bailed at step {}: {:?} exited {}",
                    step_idx + 1, script.file_name().unwrap_or_default(),
                    status.code().unwrap_or(-1)));
            }
        }
        Ok(())
    };

    call_api_with_tools_sync(
        agent_name, &prompts, &step_phases, def.temperature, def.priority,
        &effective_tools, Some(&bail_fn))?;

    Ok(AgentResult {
        node_keys: agent_batch.node_keys,
        state_dir,
    })
}

// ---------------------------------------------------------------------------
// Compatibility wrappers — delegate to AutoAgent
// ---------------------------------------------------------------------------

/// Run agent prompts through the API with tool support.
/// Convenience wrapper around AutoAgent for existing callers.
pub async fn call_api_with_tools(
    agent: &str,
    prompts: &[String],
    phases: &[String],
    temperature: Option<f32>,
    priority: i32,
    tools: &[agent_tools::Tool],
    bail_fn: Option<&(dyn Fn(usize) -> Result<(), String> + Sync)>,
) -> Result<(), String> {
    let steps: Vec<AutoStep> = prompts.iter().zip(
        phases.iter().map(String::as_str)
            .chain(std::iter::repeat(""))
    ).map(|(prompt, phase)| AutoStep {
        prompt: prompt.clone(),
        phase: phase.to_string(),
    }).collect();

    let mut auto = AutoAgent::new(
        agent.to_string(),
        tools.to_vec(),
        steps,
        temperature.unwrap_or(0.6),
        priority,
    );
    auto.run(bail_fn).await
}

/// Synchronous wrapper — runs on a dedicated thread with its own
/// tokio runtime. Safe to call from any context.
pub fn call_api_with_tools_sync(
    agent: &str,
    prompts: &[String],
    phases: &[String],
    temperature: Option<f32>,
    priority: i32,
    tools: &[agent_tools::Tool],
    bail_fn: Option<&(dyn Fn(usize) -> Result<(), String> + Sync)>,
) -> Result<(), String> {
    std::thread::scope(|s| {
        s.spawn(|| {
            let rt = tokio::runtime::Builder::new_current_thread()
                .enable_all()
                .build()
                .map_err(|e| format!("tokio runtime: {}", e))?;
            rt.block_on(
                call_api_with_tools(agent, prompts, phases, temperature, priority, tools, bail_fn)
            )
        }).join().unwrap()
    })
}

// ---------------------------------------------------------------------------
// Process management — PID tracking and subprocess spawning
// ---------------------------------------------------------------------------

pub struct SpawnResult {
    pub child: std::process::Child,
    pub log_path: PathBuf,
}

pub fn spawn_agent(
    agent_name: &str,
    state_dir: &std::path::Path,
    session_id: &str,
) -> Option<SpawnResult> {
    let def = defs::get_def(agent_name)?;
    let first_phase = def.steps.first()
        .map(|s| s.phase.as_str())
        .unwrap_or("step-0");

    let log_dir = dirs::home_dir().unwrap_or_default()
        .join(format!(".consciousness/logs/{}", agent_name));
    fs::create_dir_all(&log_dir).ok();
    let log_path = log_dir.join(format!("{}.log", store::compact_timestamp()));
    let agent_log = fs::File::create(&log_path)
        .unwrap_or_else(|_| fs::File::create("/dev/null").unwrap());

    let child = std::process::Command::new("poc-memory")
        .args(["agent", "run", agent_name, "--count", "1", "--local",
               "--state-dir", &state_dir.to_string_lossy()])
        .env("POC_SESSION_ID", session_id)
        .stdout(agent_log.try_clone().unwrap_or_else(|_| fs::File::create("/dev/null").unwrap()))
        .stderr(agent_log)
        .spawn()
        .ok()?;

    let pid = child.id();
    let pid_path = state_dir.join(format!("pid-{}", pid));
    fs::write(&pid_path, first_phase).ok();
    Some(SpawnResult { child, log_path })
}