pub mod agent_factory;
pub mod agent_prompt_provider;
pub mod agent_task_executor;
pub mod cli_session;
pub mod command;
pub mod compaction;
pub mod execution;
pub mod http;
pub mod memory_maintenance;
pub mod memory_maintenance_coordinator;
pub mod message_prepare;
pub mod outbound_dispatcher;
pub mod processor;
pub mod prompt;
pub mod provider_config_service;
pub mod runtime;
pub mod scheduled_agent_task_service;
pub mod session;
pub mod session_factory;
pub mod session_history;
pub mod session_lifecycle;
pub mod session_message_sender;
pub mod session_message_service;
pub mod session_pool;
pub mod tool_registry_factory;
pub mod ws;

use axum::{Router, routing};
use std::collections::HashMap;
use std::sync::Arc;
use tokio::net::TcpListener;
use tokio::sync::Semaphore;

use crate::bus::MessageBus;
use crate::channels::ChannelManager;
use crate::config::Config;
use crate::config::LLMProviderConfig;
use crate::logging;
use crate::scheduler::Scheduler;
use crate::skills::SkillRuntime;
use crate::tools::task::repository::TaskRepository;
use agent_task_executor::{AgentTaskExecutor, SchedulerMaintenanceService};
use outbound_dispatcher::OutboundDispatcher;
use processor::InboundProcessor;
use runtime::build_session_manager_with_sender;
use session_message_sender::BusSessionMessageSender;
use session::SessionManager;

pub struct GatewayState {
    pub config: Config,
    pub session_manager: SessionManager,
    pub channel_manager: ChannelManager,
    pub bus: Arc<MessageBus>,
    pub task_repository: Arc<dyn TaskRepository>,
}

impl GatewayState {
    pub fn from_config(config: Config) -> Result<Self, Box<dyn std::error::Error>> {
        // Get provider config for SessionManager
        let provider_config = config.get_provider_config("default")?;
        let mut provider_configs = HashMap::<String, LLMProviderConfig>::new();
        for agent_name in config.agents.keys() {
            provider_configs.insert(agent_name.clone(), config.get_provider_config(agent_name)?);
        }

        // Chat history TTL from config (default 4 hours)
        let chat_history_ttl_hours = config.gateway.chat_history_ttl_hours;
        let agent_prompt_reinject_every = config.gateway.agent_prompt_reinject_every;
        let show_tool_results = config.gateway.show_tool_results;

        let session_ttl_hours = config.gateway.session_ttl_hours;

        let skills = Arc::new(SkillRuntime::from_config(config.skills.clone()));
        let channel_manager = ChannelManager::new();
        let bus = channel_manager.bus();

        let (session_manager, task_repository) = build_session_manager_with_sender(
            agent_prompt_reinject_every,
            show_tool_results,
            config.time.timezone.clone(),
            provider_config,
            provider_configs,
            skills,
            Arc::new(BusSessionMessageSender::new(bus.clone())),
            std::collections::HashSet::new(),
            config.tools.task.clone(),
            chat_history_ttl_hours,
            session_ttl_hours,
        )?;

        Ok(Self {
            config,
            session_manager,
            channel_manager,
            bus,
            task_repository,
        })
    }

    /// Start the message processing loops
    pub async fn start_message_processing(&self) {
        let bus_for_outbound = self.bus.clone();

        // Create semaphore for controlling concurrent requests
        let max_concurrent = self.config.gateway.max_concurrent_requests;
        let semaphore = Arc::new(Semaphore::new(max_concurrent));

        // Spawn inbound processor with semaphore-controlled concurrency
        let provider_config = match self.config.get_provider_config("default") {
            Ok(config) => config,
            Err(e) => {
                tracing::error!(error = %e, "Failed to get provider config");
                return;
            }
        };
        let inbound_processor =
            InboundProcessor::new(self.bus.clone(), self.session_manager.clone(), semaphore, provider_config);
        tokio::spawn(inbound_processor.run());

        // Spawn outbound dispatcher
        let dispatcher = OutboundDispatcher::new(bus_for_outbound);
        let channel_manager = self.channel_manager.clone();

        for (name, channel) in channel_manager.channels().await {
            dispatcher.register_channel(&name, channel).await;
        }

        tokio::spawn(async move {
            tracing::info!("Outbound dispatcher started");
            dispatcher.run().await;
        });
    }
}

pub async fn run(
    host: Option<String>,
    port: Option<u16>,
) -> Result<(), Box<dyn std::error::Error>> {
    let config = Config::load_default()?;
    let timezone = config.time.parse_timezone()?;

    // Initialize logging
    logging::init_logging(timezone);
    tracing::info!("Starting PicoBot Gateway");

    let state = Arc::new(GatewayState::from_config(config)?);

    // Get provider config for channels
    let provider_config = state.config.get_provider_config("default")?;

    // Initialize and start channels
    state
        .channel_manager
        .init(&state.config, provider_config.clone())
        .await?;
    state.channel_manager.start_all().await?;

    // Start message processing (inbound processor + outbound dispatcher)
    state.start_message_processing().await;

    let (scheduler_shutdown_tx, scheduler_shutdown_rx) = tokio::sync::watch::channel(false);
    if state.config.scheduler.enabled {
        let scheduler = Scheduler::new(
            state.bus.clone(),
            state.config.scheduler.clone(),
            timezone,
            state.session_manager.store(),
            AgentTaskExecutor::new(state.session_manager.clone()),
            SchedulerMaintenanceService::new(state.session_manager.clone()),
        );

        tokio::spawn(async move {
            scheduler.run(scheduler_shutdown_rx).await;
        });
    }

    // CLI args override config file values
    let bind_host = host.unwrap_or_else(|| state.config.gateway.host.clone());
    let bind_port = port.unwrap_or(state.config.gateway.port);

    let app = Router::new()
        .route("/health", routing::get(http::health))
        .route("/ws", routing::get(ws::ws_handler))
        .with_state(state.clone());

    let addr = format!("{}:{}", bind_host, bind_port);
    let listener = TcpListener::bind(&addr).await?;
    tracing::info!(address = %addr, "Gateway listening");

    // Graceful shutdown using oneshot channel
    let (shutdown_tx, shutdown_rx) = tokio::sync::oneshot::channel::<()>();
    let channel_manager = state.channel_manager.clone();

    // Spawn ctrl_c handler
    tokio::spawn(async move {
        tokio::signal::ctrl_c().await.ok();
        tracing::info!("Shutdown signal received");
        let _ = scheduler_shutdown_tx.send(true);
        let _ = channel_manager.stop_all().await;
        let _ = shutdown_tx.send(());
    });

    // Serve with graceful shutdown
    axum::serve(listener, app)
        .with_graceful_shutdown(async {
            shutdown_rx.await.ok();
        })
        .await?;

    Ok(())
}