nexus-common 0.4.1

use pubky::Client;
use std::sync::Arc;
use thiserror::Error;
use tokio::sync::OnceCell;
use tracing::debug;

static PUBKY_CLIENT_SINGLETON: OnceCell<Arc<Client>> = OnceCell::const_new();

#[derive(Debug, Error)]
pub enum PubkyClientError {
    #[error("PubkyClient not initialized")]
    NotInitialized,

    #[error("Client initialization error: {0}")]
    ClientError(String),
}

pub struct PubkyClient;

impl PubkyClient {
    pub async fn initialise(testnet: bool) -> Result<(), PubkyClientError> {
        PUBKY_CLIENT_SINGLETON
            .get_or_try_init(|| async {
                debug!(
                    "Initialising PubkyClient in {} mode",
                    if testnet { "testnet" } else { "mainnet" }
                );
                let client = match testnet {
                    true => Client::builder()
                        .testnet()
                        .build()
                        .map_err(|e| PubkyClientError::ClientError(e.to_string()))?,
                    false => Client::builder()
                        .build()
                        .map_err(|e| PubkyClientError::ClientError(e.to_string()))?,
                };
                Ok(Arc::new(client))
            })
            .await
            .map(|_| ())
    }
    /// Retrieves an instance of the `PubkyClient`
    pub fn get() -> Result<Arc<Client>, PubkyClientError> {
        PUBKY_CLIENT_SINGLETON
            .get()
            .cloned()
            .ok_or(PubkyClientError::NotInitialized)
    }

    /// Initializes the `PUBKY_CONNECTOR_SINGLETON` with a provided `Client` instance.
    ///
    /// # Usage:
    /// - This function is primarily intended for **watcher tests** where a controlled `Client` instance
    ///   needs to be injected instead of relying on environment-based initialization
    pub async fn init_from_client(client: Client) -> Result<(), PubkyClientError> {
        PUBKY_CLIENT_SINGLETON
            .get_or_try_init(|| async { Ok(Arc::new(client)) })
            .await
            .map(|_| ())
    }
}