//! Zesdex Gateway — main entry point.
//!
//! Assembles domain + application + infrastructure layers and dispatches
//! to the requested interface: TUI (default), daemon (background IPC),
//! API server (REST), WebSocket server, gRPC server, or Web frontend.
//!
//! CLI flags are parsed via clap; run with `--help` for details.

use std::sync::Mutex;

use clap::Parser;

/// Zesdex — autonomous AI coding agent.
#[derive(Parser, Debug)]
#[command(name = "zesdex", version, about = "Autonomous AI coding agent with TUI")]
struct Cli {
    /// Run as background daemon with IPC socket
    #[arg(long)]
    daemon: bool,

    /// Attach TUI client to a running daemon session
    #[arg(long)]
    attach: Option<String>,

    /// Run REST API server
    #[arg(long)]
    api: bool,

    /// REST API port
    #[arg(long, default_value_t = 8080)]
    api_port: u16,

    /// Run WebSocket server
    #[arg(long)]
    ws: bool,

    /// WebSocket port
    #[arg(long, default_value_t = 8081)]
    ws_port: u16,

    /// Run gRPC server
    #[arg(long)]
    grpc: bool,

    /// gRPC port
    #[arg(long, default_value_t = 50051)]
    grpc_port: u16,

    /// Serve web frontend
    #[arg(long)]
    web: bool,

    /// Web frontend port
    #[arg(long, default_value_t = 3000)]
    web_port: u16,
}

fn main() -> anyhow::Result<()> {
    let cli = Cli::parse();

    // ── Setup logging ────────────────────────────────────────────────────
    let log_dir = dirs::data_dir()
        .unwrap_or_else(|| std::path::PathBuf::from("."))
        .join("zesdex");
    let _ = std::fs::create_dir_all(&log_dir);
    let log_path = log_dir.join("zesdex.log");
    let log_file = std::fs::OpenOptions::new()
        .create(true)
        .append(true)
        .open(&log_path)
        .unwrap_or_else(|_| {
            std::fs::OpenOptions::new()
                .write(true)
                .open("/dev/null")
                .expect("cannot open /dev/null")
        });

    tracing_subscriber::fmt()
        .with_env_filter(
            tracing_subscriber::EnvFilter::try_from_default_env()
                .unwrap_or_else(|_| tracing_subscriber::EnvFilter::new("info")),
        )
        .with_writer(Mutex::new(log_file))
        .init();

    tracing::info!("zesdex gateway starting");

    // ── Dispatch to interface ────────────────────────────────────────────
    // Validate mutually exclusive flags
    let mode_count = [cli.daemon, cli.api, cli.ws, cli.grpc, cli.web]
        .iter()
        .filter(|&&b| b)
        .count()
        + if cli.attach.is_some() { 1 } else { 0 };

    if mode_count > 1 {
        anyhow::bail!(
            "Cannot specify multiple modes: --daemon, --attach, --api, --ws, --grpc, --web are mutually exclusive"
        );
    }

    if cli.daemon {
        tracing::info!("starting in daemon mode");
        zesdex_daemon::server::run_daemon()?;
    } else if let Some(session_id) = cli.attach {
        tracing::info!("starting in attach mode for session {session_id}");
        zesdex_daemon::client::run_attach(&session_id)?;
    } else if cli.api {
        tracing::info!("starting in API server mode");
        run_api_server(cli.api_port)?;
    } else if cli.ws {
        tracing::info!("starting in WebSocket server mode");
        run_ws_server(cli.ws_port)?;
    } else if cli.grpc {
        tracing::info!("starting in gRPC server mode");
        run_grpc_server(cli.grpc_port)?;
    } else if cli.web {
        tracing::info!("starting in web server mode");
        run_web_server(cli.web_port)?;
    } else {
        // Default: run TUI single-process mode
        tracing::info!("starting in TUI single-process mode");
        run_tui_single_process()?;
    }

    Ok(())
}

/// Run the TUI in single-process mode (TUI + agent in one process).
fn run_tui_single_process() -> anyhow::Result<()> {
    zesdex_tui::run_single_process()
}

/// Run the REST API server.
fn run_api_server(port: u16) -> anyhow::Result<()> {
    let rt = tokio::runtime::Runtime::new()?;
    rt.block_on(async {
        let store = zesdex_domain::core::Store::new();
        let state = zesdex_api::ApiState::new(
            store.base_dir.clone(),
            "dev-secret",
            "",
            "deepseek-v4-flash-free",
            Some("https://opencode.ai/zen/v1".to_string()),
        );
        let app = zesdex_api::build_router(state);
        let addr = std::net::SocketAddr::from(([0, 0, 0, 0], port));
        tracing::info!("REST API server listening on http://{addr}/api/v1/health");
        let listener = tokio::net::TcpListener::bind(addr).await?;
        axum::serve(listener, app).await?;
        Ok::<_, anyhow::Error>(())
    })?;
    Ok(())
}

/// Run the WebSocket server.
fn run_ws_server(port: u16) -> anyhow::Result<()> {
    let rt = tokio::runtime::Runtime::new()?;
    rt.block_on(async { zesdex_ws::run_server(port).await })?;
    Ok(())
}

/// Run the gRPC server.
fn run_grpc_server(port: u16) -> anyhow::Result<()> {
    let rt = tokio::runtime::Runtime::new()?;
    rt.block_on(async { zesdex_grpc::run_server(port).await })?;
    Ok(())
}

/// Serve the web frontend.
fn run_web_server(port: u16) -> anyhow::Result<()> {
    let rt = tokio::runtime::Runtime::new()?;
    rt.block_on(async { zesdex_web::run_server(port, None).await })?;
    Ok(())
}