//! Functions for environment detection that need to be shared across crates.

/// Serialized provider context passed from a parent LHA session to a delegated
/// `lha exec` job.
pub const LHA_AGENT_JOB_PROVIDER_CONTEXT_ENV_VAR: &str = "LHA_AGENT_JOB_PROVIDER_CONTEXT";

/// Ephemeral auth token passed from a parent LHA session to a delegated
/// `lha exec` job. The child consumes and removes this during startup.
pub const LHA_AGENT_JOB_AUTH_TOKEN_ENV_VAR: &str = "LHA_AGENT_JOB_AUTH_TOKEN";

/// Serialized sandbox policy passed from a parent LHA session to a delegated
/// `lha exec` job. The child consumes and removes this during startup.
pub const LHA_AGENT_JOB_SANDBOX_POLICY_ENV_VAR: &str = "LHA_AGENT_JOB_SANDBOX_POLICY";

/// Serialized Windows sandbox level passed from a parent LHA session to a
/// delegated `lha exec` job. The child consumes and removes this during
/// startup.
pub const LHA_AGENT_JOB_WINDOWS_SANDBOX_LEVEL_ENV_VAR: &str = "LHA_AGENT_JOB_WINDOWS_SANDBOX_LEVEL";

fn env_var_set(key: &str) -> bool {
    std::env::var(key).is_ok_and(|v| !v.trim().is_empty())
}

/// Returns true if the current process is running under Windows Subsystem for Linux.
pub fn is_wsl() -> bool {
    #[cfg(target_os = "linux")]
    {
        if std::env::var_os("WSL_DISTRO_NAME").is_some() {
            return true;
        }
        match std::fs::read_to_string("/proc/version") {
            Ok(version) => version.to_lowercase().contains("microsoft"),
            Err(_) => false,
        }
    }
    #[cfg(not(target_os = "linux"))]
    {
        false
    }
}

/// Returns true when LHA is likely running in an environment without a usable GUI.
///
/// This is intentionally conservative and is used by frontends to avoid flows that would try to
/// open a browser (e.g. device-code auth fallback).
pub fn is_headless_environment() -> bool {
    if env_var_set("CI")
        || env_var_set("SSH_CONNECTION")
        || env_var_set("SSH_CLIENT")
        || env_var_set("SSH_TTY")
    {
        return true;
    }

    #[cfg(target_os = "linux")]
    {
        if !env_var_set("DISPLAY") && !env_var_set("WAYLAND_DISPLAY") {
            return true;
        }
    }

    false
}
