#![cfg_attr(
    not(target_os = "windows"),
    allow(dead_code, unused_imports, unreachable_code)
)]

mod api;
pub mod db;
pub mod error;
mod handlers;
mod mcp;
mod models;
mod router;
mod search;
mod state;
mod store;
mod tools;

use crate::api::rest::GateSetReq;
use crate::router::MemoryHandler;
use crate::state::MemoryState;
use clap::{Parser, Subcommand};
use std::collections::HashMap;
use std::path::PathBuf;
use std::sync::atomic::AtomicUsize;
use std::sync::{Arc, RwLock};
use std::time::Duration;
use tokio::sync::mpsc;

#[derive(Parser)]
#[command(author, version = env!("APP_VERSION"), about = "Antigravity MCP Memory Server", long_about = None)]
struct Cli {
    #[command(subcommand)]
    command: Option<Commands>,
    /// Target URL for the proxy to connect to (e.g., http://127.0.0.1:3000)
    #[arg(long)]
    target: Option<String>,
    /// Send a shutdown request to the currently running server
    #[arg(long)]
    exit: bool,
    /// Send a shutdown request to the existing server and wait for it to exit
    #[arg(long)]
    restart: bool,
}

#[derive(Subcommand)]
enum Commands {
    /// Manage authorization gates and verification for actions
    Gate {
        #[command(subcommand)]
        subcmd: GateCommands,
    },
}

#[derive(Subcommand)]
enum GateCommands {
    Set {
        #[arg(long)]
        action: String,
        #[arg(long)]
        target: String,
        #[arg(long)]
        namespace: Option<String>,
        #[arg(short = 'p', long = "param")]
        params: Vec<String>,
        #[arg(long, conflicts_with = "block")]
        authorize: bool,
        #[arg(long, conflicts_with = "authorize")]
        block: bool,
        #[arg(long)]
        reason: Option<String>,
    },
    Verify {
        #[arg(long)]
        action: String,
        #[arg(long)]
        target: String,
        #[arg(long)]
        namespace: Option<String>,
        #[arg(short = 'p', long = "param")]
        params: Vec<String>,
        #[arg(long)]
        consume: bool,
    },
}

pub struct AppState {
    handler: Arc<MemoryHandler>,
    clients: RwLock<HashMap<String, mpsc::Sender<String>>>,
    next_id: AtomicUsize,
}

async fn index_committer_worker(state: Arc<MemoryState>) {
    loop {
        tokio::time::sleep(Duration::from_secs(5)).await;
        // Periodically commit the search index to persist inline indexing operations
        let idx_opt = state.search_index.read().ok().map(|idx| idx.clone());
        if let Some(idx) = idx_opt {
            let _ = idx.commit().await;
        }
    }
}

async fn run_server(state: Arc<MemoryState>) -> Result<(), Box<dyn std::error::Error>> {
    state.rebuild_index().await;
    tokio::spawn(index_committer_worker(Arc::clone(&state)));
    let app_state = Arc::new(AppState {
        handler: Arc::new(MemoryHandler::new(Arc::clone(&state))),
        clients: RwLock::new(HashMap::new()),
        next_id: AtomicUsize::new(1),
    });

    let app_state_clone = Arc::clone(&app_state);
    let mut rx = state.activity_tx.subscribe();
    tokio::spawn(async move {
        loop {
            match rx.recv().await {
                Ok(msg) => {
                    let senders: Vec<_> = app_state_clone
                        .clients
                        .read()
                        .unwrap_or_else(|e| e.into_inner())
                        .values()
                        .cloned()
                        .collect();
                    for client_tx in senders {
                        let _ = client_tx.try_send(msg.clone());
                    }
                }
                Err(tokio::sync::broadcast::error::RecvError::Closed) => break,
                Err(tokio::sync::broadcast::error::RecvError::Lagged(_)) => continue,
            }
        }
    });

    let app = api::setup::create_router(app_state);

    tracing::info!("MCP Memory Server running on http://127.0.0.1:3000/sse");
    let addr = std::env::var("MCP_PORT").unwrap_or_else(|_| "3000".to_string());
    let addr: std::net::SocketAddr = format!("127.0.0.1:{}", addr)
        .parse()
        .expect("Invalid bind address");

    let listener = match tokio::net::TcpListener::bind(&addr).await {
        Ok(l) => l,
        Err(e) => {
            let log_path = dirs::home_dir()
                .unwrap_or_default()
                .join(".gemini/mcp_memory/daemon_error.log");
            let _ =
                tokio::fs::write(&log_path, format!("Failed to bind to {}: {}\n", addr, e)).await;
            return Ok(());
        }
    };
    if let Err(e) = axum::serve(listener, app.into_make_service()).await {
        let log_path = dirs::home_dir()
            .unwrap_or_default()
            .join(".gemini/mcp_memory/daemon_error.log");
        let _ = tokio::fs::write(&log_path, format!("Server crashed: {}\n", e)).await;
    }
    Ok(())
}

fn init_logging(app_name: &str) -> Option<tracing_appender::non_blocking::WorkerGuard> {
    let base_dir = std::env::var("MCP_MEMORY_STORE_DIR").unwrap_or_else(|_| {
        dirs::home_dir()
            .map(|mut h| {
                h.push(".gemini/mcp_memory");
                h.to_string_lossy().to_string()
            })
            .unwrap_or_else(|| ".gemini/mcp_memory".into())
    });
    let log_dir = std::path::PathBuf::from(base_dir).join("logs");
    std::fs::create_dir_all(&log_dir).unwrap_or_default();

    let file_appender = tracing_appender::rolling::daily(log_dir, format!("{}.log", app_name));
    let (non_blocking, guard) = tracing_appender::non_blocking(file_appender);

    let _ = tracing_subscriber::fmt()
        .with_writer(non_blocking)
        .with_ansi(false)
        .with_max_level(tracing::Level::INFO)
        .with_thread_ids(true)
        .with_thread_names(true)
        .try_init();

    Some(guard)
}

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let _guard = init_logging("mcp-memory-server");
    let cli = Cli::parse();

    let base_dir = std::env::var("MCP_MEMORY_STORE_DIR").unwrap_or_else(|_| {
        dirs::home_dir()
            .map(|mut h| {
                h.push(".gemini/mcp_memory");
                h.to_string_lossy().into_owned()
            })
            .unwrap_or_else(|| ".gemini/mcp_memory".into())
    });
    let base = PathBuf::from(base_dir);

    if cli.exit {
        let port = std::env::var("MCP_PORT").unwrap_or_else(|_| "3000".to_string());
        let token = std::fs::read_to_string(base.join("admin.token")).unwrap_or_default();
        let mut cmd = std::process::Command::new("curl");
        cmd.arg("-k").arg("-X").arg("POST");
        if !token.is_empty() {
            cmd.arg("-H")
                .arg(format!("Authorization: Bearer {}", token.trim()));
        }
        let _ = cmd
            .arg(format!("http://127.0.0.1:{}/shutdown", port))
            .output();

        if cli.restart {
            std::thread::sleep(Duration::from_secs(2));
        } else {
            return Ok(());
        }
    }

    if let Some(Commands::Gate { subcmd }) = cli.command {
        let port = std::env::var("MCP_PORT").unwrap_or_else(|_| "3000".to_string());
        let rt = tokio::runtime::Runtime::new()?;
        match subcmd {
            GateCommands::Set {
                action,
                target,
                namespace,
                params,
                authorize,
                block,
                reason,
            } => {
                let mut pmap = HashMap::new();
                for p in params {
                    if let Some((k, v)) = p.split_once('=') {
                        pmap.insert(k.to_string(), v.to_string());
                    }
                }
                let req = GateSetReq {
                    action,
                    target,
                    namespace,
                    params: pmap,
                    authorize: if authorize { Some(true) } else { None },
                    block: if block { Some(true) } else { None },
                    reason,
                };
                rt.block_on(async {
                    let client = reqwest::Client::new();
                    let res = client
                        .post(format!("http://127.0.0.1:{}/gate/set", port))
                        .json(&req)
                        .send()
                        .await;
                    match res {
                        Ok(r) if r.status().is_success() => println!("Gate updated successfully"),
                        Ok(r) => println!("Failed to update gate: {}", r.status()),
                        Err(e) => println!("Error connecting to server: {}", e),
                    }
                });
            }
            GateCommands::Verify {
                action,
                target,
                namespace,
                params: _,
                consume,
            } => {
                let mut url = format!(
                    "http://127.0.0.1:{}/gate/verify?action={}&target={}&consume={}",
                    port, action, target, consume
                );
                if let Some(ns) = namespace {
                    url.push_str(&format!("&namespace={}", ns));
                }
                rt.block_on(async {
                    let res = reqwest::get(&url).await;
                    match res {
                        Ok(r) if r.status().is_success() => std::process::exit(0),
                        Ok(r) if r.status() == reqwest::StatusCode::FORBIDDEN => {
                            let text = r.text().await.unwrap_or_default();
                            eprintln!("{}", text);
                            std::process::exit(1);
                        }
                        Ok(r) if r.status() == reqwest::StatusCode::NOT_FOUND => {
                            eprintln!("Action not yet authorized.");
                            std::process::exit(2);
                        }
                        Ok(r) => {
                            eprintln!("Unexpected status: {}", r.status());
                            std::process::exit(3);
                        }
                        Err(e) => {
                            eprintln!("Error connecting to server: {}", e);
                            std::process::exit(4);
                        }
                    }
                });
            }
        }
        return Ok(());
    }

    let token = uuid::Uuid::new_v4().to_string();
    std::fs::write(base.join("admin.token"), &token).unwrap_or_default();

    let rt = tokio::runtime::Builder::new_multi_thread()
        .enable_all()
        .build()
        .unwrap();

    rt.block_on(async {
        let state = Arc::new(MemoryState::new(&base.to_string_lossy()));
        if let Err(e) = run_server(state).await {
            tracing::error!("Server error: {}", e);
        }
    });

    Ok(())
}