use prometeu_hal::RuntimePlatform;
use prometeu_hal::app_mode::AppMode;
use prometeu_hal::log::LogSource;
use prometeu_system::task::TaskId;
use prometeu_system::{LifecycleError, SystemOS};

#[derive(Debug, Clone, PartialEq, Eq)]
pub(crate) enum ResidentGameTerminationOutcome {
    NoResidentGame,
    Terminated { task_id: TaskId, title: String },
}

pub(crate) fn terminate_resident_game(
    os: &mut SystemOS,
    platform: &mut dyn RuntimePlatform,
    log_manual_hub_kill: bool,
) -> Result<ResidentGameTerminationOutcome, LifecycleError> {
    let Some(task_id) = os.lifecycle().resident_game_task() else {
        return Ok(ResidentGameTerminationOutcome::NoResidentGame);
    };

    let title = os
        .sessions()
        .vm_session_for_task(task_id)
        .map(|session| session.title.clone())
        .unwrap_or_else(|| "<unknown>".to_string());

    let terminated = os.lifecycle().terminate_resident_game()?;
    let Some(task_id) = terminated else {
        return Ok(ResidentGameTerminationOutcome::NoResidentGame);
    };

    os.vm().transition_render_owner(AppMode::Shell, 0);
    platform.game2d_frame_composer().unbind_scene();
    platform.assets_mut().shutdown();

    if log_manual_hub_kill {
        os.info(LogSource::Hub, format!("Resident game killed from Hub: {title}"));
    }

    Ok(ResidentGameTerminationOutcome::Terminated { task_id, title })
}