// file: crates/ksp-app-config-desk/src/bootstrap.rs
// version: 6

//! Config and Logging bootstrap for the desktop application.

/// Crate-internal `LoggingStartup` state shared across the owning crate.
pub(crate) struct LoggingStartup {
    /// Stores the guard value for this state.
    pub(crate) guard: ksp_logging_lib::LoggingGuard,
    /// Stores the active profile id value for this state.
    pub(crate) active_profile_id: std::option::Option<String>,
    /// Stores the selection source value for this state.
    pub(crate) selection_source: String,
    /// Stores the fallback active value for this state.
    pub(crate) fallback_active: bool,
    /// Stores the startup diagnostic value for this state.
    pub(crate) startup_diagnostic: std::option::Option<crate::CommandErrorDto>,
}

enum LoggingStartupPlan {
    Managed {
        active_profile_id: String,
        settings: ksp_logging_lib::LoggingSettings,
    },
    Fallback {
        initial_error: ksp_core_lib::Error,
        diagnostic: crate::CommandErrorDto,
        settings: ksp_logging_lib::LoggingSettings,
    },
}

/// Executes the crate-internal config management operation for the owning module.
pub(crate) fn config_management(arguments: &[std::ffi::OsString]) -> ksp_core_lib::Result<ksp_config_lib::ConfigManagement> {
    let bootstrap = ksp_config_lib::ConfigBootstrapOptions::from_args(arguments);
    let bootstrap = match bootstrap {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(error),
    };
    let registry = ksp_config_lib::ConfigFileRegistry::from_args(arguments);
    let registry = match registry {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(error),
    };
    let engine = ksp_config_lib::ConfigDocumentEngine::new(bootstrap, registry);
    return std::result::Result::Ok(ksp_config_lib::ConfigManagement::new(engine));
}

/// Executes the crate-internal initialize logging operation for the owning module.
pub(crate) fn initialize_logging(
    management: &ksp_config_lib::ConfigManagement,
    runtime_identity: &ksp_logging_lib::LoggingRuntimeIdentity,
) -> ksp_core_lib::Result<crate::LoggingStartup> {
    let plan = resolve_logging_startup(management);
    return match plan {
        LoggingStartupPlan::Managed { active_profile_id, settings } => {
            let guard = ksp_logging_lib::initialize_with_identity(&settings, runtime_identity);
            match guard {
                std::result::Result::Ok(guard) => {
                    ksp_logging_lib::info!(
                        target: crate::TRACING_TARGET,
                        domain = crate::TRACING_DOMAIN_BOOTSTRAP,
                        active_profile = active_profile_id.as_str(),
                        "initialized Config Desk logging from managed configuration"
                    );
                    std::result::Result::Ok(LoggingStartup {
                        guard,
                        active_profile_id: std::option::Option::Some(active_profile_id),
                        selection_source: "default_profile".to_owned(),
                        fallback_active: false,
                        startup_diagnostic: std::option::Option::None,
                    })
                },
                std::result::Result::Err(error) => initialize_fallback_logging(error, runtime_identity),
            }
        },
        LoggingStartupPlan::Fallback { initial_error, diagnostic, settings } => {
            initialize_planned_fallback_logging(initial_error, diagnostic, settings, runtime_identity)
        },
    };
}

fn fallback_logging_settings() -> ksp_logging_lib::LoggingSettings {
    return ksp_logging_lib::LoggingSettings::new(
        ksp_logging_lib::LogFilterLevel::Info,
        ksp_logging_lib::SpanEvents::Off,
        std::option::Option::Some(ksp_logging_lib::ConsoleSettings::stderr()),
        std::vec::Vec::new(),
    );
}

fn resolve_logging_startup(management: &ksp_config_lib::ConfigManagement) -> LoggingStartupPlan {
    let environment = ksp_config_lib::ConfigEnvironment::load();
    let environment = match environment {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return fallback_startup_plan(error),
    };
    let resolved = management.engine().load_resolved_logging_config(std::option::Option::None, &environment);
    let resolved = match resolved {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return fallback_startup_plan(error),
    };
    return LoggingStartupPlan::Managed { active_profile_id: resolved.profile_id().to_owned(), settings: resolved.into_settings() };
}

fn fallback_startup_plan(initial_error: ksp_core_lib::Error) -> LoggingStartupPlan {
    let diagnostic = crate::CommandErrorDto::from_error(&initial_error);
    return LoggingStartupPlan::Fallback { initial_error, diagnostic, settings: fallback_logging_settings() };
}

fn initialize_fallback_logging(
    initial_error: ksp_core_lib::Error,
    runtime_identity: &ksp_logging_lib::LoggingRuntimeIdentity,
) -> ksp_core_lib::Result<crate::LoggingStartup> {
    let diagnostic = crate::CommandErrorDto::from_error(&initial_error);
    return initialize_planned_fallback_logging(initial_error, diagnostic, fallback_logging_settings(), runtime_identity);
}

fn initialize_planned_fallback_logging(
    initial_error: ksp_core_lib::Error,
    diagnostic: crate::CommandErrorDto,
    settings: ksp_logging_lib::LoggingSettings,
    runtime_identity: &ksp_logging_lib::LoggingRuntimeIdentity,
) -> ksp_core_lib::Result<crate::LoggingStartup> {
    let guard = ksp_logging_lib::initialize_with_identity(&settings, runtime_identity);
    let guard = match guard {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(fallback_error) => {
            return std::result::Result::Err(
                ksp_core_lib::Error::new(crate::ERROR_CODE_LOGGING_BOOTSTRAP_FAILED, "Cannot initialize Config Desk fallback Logging runtime")
                    .with_context("initial_error_domain", initial_error.code().domain())
                    .with_context("initial_error_code", initial_error.code().code())
                    .with_source(fallback_error),
            );
        },
    };
    ksp_logging_lib::warn!(
        target: crate::TRACING_TARGET,
        domain = crate::TRACING_DOMAIN_BOOTSTRAP,
        error_domain = diagnostic.domain.as_str(),
        error_code = diagnostic.code.as_str(),
        "managed Logging configuration is unavailable; using transient in-memory fallback"
    );
    return std::result::Result::Ok(LoggingStartup {
        guard,
        active_profile_id: std::option::Option::None,
        selection_source: "fallback".to_owned(),
        fallback_active: true,
        startup_diagnostic: std::option::Option::Some(diagnostic),
    });
}

#[cfg(test)]
#[path = "../unit_tests/bootstrap.rs"]
mod tests;