// Dashboard module for LLM Proxy Gateway

mod auth;
mod clients;
mod models;
mod providers;
pub mod sessions;
mod system;
mod usage;
mod users;
mod websocket;

use axum::{
    extract::{Request, State},
    middleware::Next,
    response::Response,
    Router,
    routing::{delete, get, post, put},
};
use axum::http::{header, HeaderValue};
use serde::Serialize;
use tower_http::{
    limit::RequestBodyLimitLayer,
    set_header::SetResponseHeaderLayer,
};

use crate::state::AppState;
use sessions::SessionManager;

// Dashboard state
#[derive(Clone)]
struct DashboardState {
    app_state: AppState,
    session_manager: SessionManager,
}

// API Response types
#[derive(Serialize)]
struct ApiResponse<T> {
    success: bool,
    data: Option<T>,
    error: Option<String>,
}

impl<T> ApiResponse<T> {
    fn success(data: T) -> Self {
        Self {
            success: true,
            data: Some(data),
            error: None,
        }
    }

    fn error(error: String) -> Self {
        Self {
            success: false,
            data: None,
            error: Some(error),
        }
    }
}

/// Rate limiting middleware for dashboard routes
async fn dashboard_rate_limit_middleware(
    State(_dashboard_state): State<DashboardState>,
    request: Request,
    next: Next,
) -> Result<Response, crate::errors::AppError> {
    // Bypass rate limiting for dashboard routes to prevent "Failed to load statistics"
    // when the UI makes many concurrent requests on load.
    // Dashboard endpoints are already secured via auth::require_admin.
    Ok(next.run(request).await)
}

// Dashboard routes
pub fn router(state: AppState) -> Router {
    let session_manager = SessionManager::new(24); // 24-hour session TTL
    let dashboard_state = DashboardState {
        app_state: state,
        session_manager,
    };

    // Security headers
    let csp_header: SetResponseHeaderLayer<HeaderValue> = SetResponseHeaderLayer::overriding(
        header::CONTENT_SECURITY_POLICY,
        "default-src 'self'; script-src 'self' 'unsafe-inline' https://cdn.jsdelivr.net; style-src 'self' 'unsafe-inline' https://cdnjs.cloudflare.com https://fonts.googleapis.com; font-src 'self' https://cdnjs.cloudflare.com https://fonts.gstatic.com; img-src 'self' data:; connect-src 'self' ws:;"
            .parse()
            .unwrap(),
    );
    let x_frame_options: SetResponseHeaderLayer<HeaderValue> = SetResponseHeaderLayer::overriding(
        header::X_FRAME_OPTIONS,
        "DENY".parse().unwrap(),
    );
    let x_content_type_options: SetResponseHeaderLayer<HeaderValue> = SetResponseHeaderLayer::overriding(
        header::X_CONTENT_TYPE_OPTIONS,
        "nosniff".parse().unwrap(),
    );
    let strict_transport_security: SetResponseHeaderLayer<HeaderValue> = SetResponseHeaderLayer::overriding(
        header::STRICT_TRANSPORT_SECURITY,
        "max-age=31536000; includeSubDomains".parse().unwrap(),
    );

    Router::new()
        // Static file serving
        .fallback_service(tower_http::services::ServeDir::new("static"))
        // WebSocket endpoint
        .route("/ws", get(websocket::handle_websocket))
        // API endpoints
        .route("/api/auth/login", post(auth::handle_login))
        .route("/api/auth/status", get(auth::handle_auth_status))
        .route("/api/auth/logout", post(auth::handle_logout))
        .route("/api/auth/change-password", post(auth::handle_change_password))
        .route(
            "/api/users",
            get(users::handle_get_users).post(users::handle_create_user),
        )
        .route(
            "/api/users/{id}",
            put(users::handle_update_user).delete(users::handle_delete_user),
        )
        .route("/api/usage/summary", get(usage::handle_usage_summary))
        .route("/api/usage/time-series", get(usage::handle_time_series))
        .route("/api/usage/clients", get(usage::handle_clients_usage))
        .route("/api/usage/providers", get(usage::handle_providers_usage))
        .route("/api/usage/detailed", get(usage::handle_detailed_usage))
        .route("/api/analytics/breakdown", get(usage::handle_analytics_breakdown))
        .route("/api/models", get(models::handle_get_models))
        .route("/api/models/{id}", put(models::handle_update_model))
        .route(
            "/api/clients",
            get(clients::handle_get_clients).post(clients::handle_create_client),
        )
        .route(
            "/api/clients/{id}",
            get(clients::handle_get_client)
                .put(clients::handle_update_client)
                .delete(clients::handle_delete_client),
        )
        .route("/api/clients/{id}/usage", get(clients::handle_client_usage))
        .route(
            "/api/clients/{id}/tokens",
            get(clients::handle_get_client_tokens).post(clients::handle_create_client_token),
        )
        .route(
            "/api/clients/{id}/tokens/{token_id}",
            delete(clients::handle_delete_client_token),
        )
        .route("/api/providers", get(providers::handle_get_providers))
        .route(
            "/api/providers/{name}",
            get(providers::handle_get_provider).put(providers::handle_update_provider),
        )
        .route("/api/providers/{name}/test", post(providers::handle_test_provider))
        .route("/api/system/health", get(system::handle_system_health))
        .route("/api/system/metrics", get(system::handle_system_metrics))
        .route("/api/system/logs", get(system::handle_system_logs))
        .route("/api/system/backup", post(system::handle_system_backup))
        .route(
            "/api/system/settings",
            get(system::handle_get_settings).post(system::handle_update_settings),
        )
        // Security layers
        .layer(RequestBodyLimitLayer::new(10 * 1024 * 1024)) // 10 MB limit
        .layer(csp_header)
        .layer(x_frame_options)
        .layer(x_content_type_options)
        .layer(strict_transport_security)
        // Rate limiting middleware
        .layer(axum::middleware::from_fn_with_state(
            dashboard_state.clone(),
            dashboard_rate_limit_middleware,
        ))
        .with_state(dashboard_state)
}