// file: kb-app-demo-desktop/src/splash.rs
// version: 1

//! Splash-window payloads and startup sequencing helpers.

use tauri::Emitter; // rust-rules: trait-import
use ts_rs::TS; // rust-rules: derive-import

/// Minimum splash duration before the main window is shown.
pub(crate) const SPLASH_MINIMUM_MS: u64 = 900;
/// Splash fade duration.
pub(crate) const SPLASH_FADE_MS: u32 = 500;
/// Delay after fade-out before destroying the splash window.
pub(crate) const SPLASH_CLOSE_WAIT_MS: u64 = 550;

/// Command sent from Rust to the splash frontend.
#[derive(Clone, Debug, serde::Deserialize, serde::Serialize, TS)]
#[ts(export, export_to = "../frontend/ts/bindings/kb_app_demo_desktop/splash/SplashOrder.ts")]
pub(crate) struct SplashOrder {
    /// Command name.
    pub(crate) order: std::string::String,
    /// Optional message.
    pub(crate) msg: std::option::Option<std::string::String>,
    /// Optional status.
    pub(crate) status: std::option::Option<std::string::String>,
    /// Optional animation duration in milliseconds.
    pub(crate) duration_ms: std::option::Option<u32>,
}

/// Emits one splash command.
pub(crate) fn emit_splash_order(
    splash_window: &tauri::WebviewWindow,
    order: &str,
    msg: std::option::Option<&str>,
    status: std::option::Option<&str>,
    duration_ms: std::option::Option<u32>,
) {
    let payload = SplashOrder {
        order: order.to_string(),
        msg: msg.map(std::string::ToString::to_string),
        status: status.map(std::string::ToString::to_string),
        duration_ms,
    };
    let emit_result = splash_window.emit("splash", payload);
    if let std::result::Result::Err(error) = emit_result {
        tracing::error!(target: crate::TRACING_TARGET, "cannot emit splash order '{order}': {error:?}");
    }
}

/// Waits until the configured minimum splash duration has elapsed.
pub(crate) async fn wait_until_minimum(start: tokio::time::Instant, minimum_ms: u64) {
    let minimum = std::time::Duration::from_millis(minimum_ms);
    let elapsed = start.elapsed();
    if elapsed >= minimum {
        return;
    }
    tokio::time::sleep(minimum - elapsed).await;
}

#[cfg(test)]
mod tests {
    #[test]
    fn splash_order_serializes_duration_ms() {
        let order = super::SplashOrder {
            order: "fadein".to_string(),
            msg: std::option::Option::None,
            status: std::option::Option::None,
            duration_ms: std::option::Option::Some(500),
        };
        let value_result = serde_json::to_value(order);
        let value = match value_result {
            std::result::Result::Ok(value) => value,
            std::result::Result::Err(error) => panic!("cannot serialize splash order: {error}"),
        };
        assert_eq!(value["duration_ms"], serde_json::json!(500));
    }

    #[test]
    fn splash_timing_is_ordered() {
        assert!(super::SPLASH_MINIMUM_MS > 0);
        assert!(super::SPLASH_FADE_MS > 0);
        assert!(super::SPLASH_CLOSE_WAIT_MS >= u64::from(super::SPLASH_FADE_MS));
    }
}