indodax_cli/

client.rs

use crate::auth::Signer;
use crate::errors::{ErrorCategory, IndodaxError};
use reqwest::{Client, RequestBuilder, Response, StatusCode};
use serde::de::DeserializeOwned;
use std::collections::{HashMap, BTreeMap};
use tokio::sync::Mutex;

use web_time::{Duration, Instant};

#[cfg(target_arch = "wasm32")]
async fn sleep(duration: Duration) {
    let mut cb = |resolve: js_sys::Function, _reject: js_sys::Function| {
        web_sys::window()
            .unwrap()
            .set_timeout_with_callback_and_timeout_and_arguments_0(&resolve, duration.as_millis() as i32)
            .unwrap();
    };
    let p = js_sys::Promise::new(&mut cb);
    wasm_bindgen_futures::JsFuture::from(p).await.unwrap();
}

#[cfg(not(target_arch = "wasm32"))]
use tokio::time::sleep;

const PRIVATE_V1_URL: &str = "https://indodax.com/tapi";
const PRIVATE_V2_BASE: &str = "https://tapi.btcapi.net";
const WS_TOKEN_URL: &str = "https://indodax.com/api/private_ws/v1/generate_token";
const MAX_RETRIES: u32 = 3;

#[cfg(not(target_arch = "wasm32"))]
fn public_base_url() -> String {
    "https://indodax.com".to_owned()
}

#[cfg(not(target_arch = "wasm32"))]
fn api_base_url() -> String {
    "https://api.indodax.com".to_owned()
}

#[cfg(target_arch = "wasm32")]
fn public_base_url() -> String {
    let base = option_env!("INDODAX_PUBLIC_BASE_URL").unwrap_or("/api/indodax");
    if base.starts_with("http://") || base.starts_with("https://") {
        return base.to_owned();
    }

    let origin = web_sys::window()
        .and_then(|window| window.location().origin().ok())
        .unwrap_or_default();

    format!("{origin}{base}")
}

#[cfg(target_arch = "wasm32")]
fn api_base_url() -> String {
    // For WASM, we usually proxy through the same origin or a specific path
    public_base_url()
}

#[derive(Debug)]
struct RateLimiterState {
    tokens: u64,
    last_refill: Instant,
}

/// Token-bucket rate limiter for proactive 429 avoidance.
#[derive(Debug)]
struct RateLimiter {
    capacity: u64,
    refill_per_sec: u64,
    state: Mutex<RateLimiterState>,
}

impl RateLimiter {
    fn new(capacity: u64, refill_per_sec: u64) -> Self {
        Self {
            capacity,
            refill_per_sec,
            state: Mutex::new(RateLimiterState {
                tokens: capacity,
                last_refill: Instant::now(),
            }),
        }
    }

    fn from_env() -> Self {
        #[cfg(not(target_arch = "wasm32"))]
        let rps = std::env::var("INDODAX_RATE_LIMIT")
            .ok()
            .and_then(|v| v.parse::<u64>().ok())
            .unwrap_or(5)
            .max(1);

        #[cfg(target_arch = "wasm32")]
        let rps = 5;

        Self::new(rps, rps)
    }

    async fn acquire(&self) {
        loop {
            let mut state = self.state.lock().await;
            let elapsed = state.last_refill.elapsed();
            if elapsed >= Duration::from_secs(1) {
                let secs = elapsed.as_secs();
                let capped = secs.min(60); // cap to 60s to guard against clock jumps
                let add = self.refill_per_sec * capped;
                state.tokens = state.tokens.saturating_add(add).min(self.capacity);
                state.last_refill += Duration::from_secs(capped);
            }
            if state.tokens > 0 {
                state.tokens -= 1;
                return;
            }
            let elapsed_ms = elapsed.as_millis().min(u128::from(u64::MAX)) as u64;
            let wait = if elapsed_ms < 1000 {
                Duration::from_millis(1000 - elapsed_ms)
            } else {
                Duration::from_millis(50)
            };
            drop(state);
            sleep(wait.max(Duration::from_millis(10))).await;
        }
    }
}

#[derive(Debug)]
pub struct IndodaxClient {
    http: Client,
    signer: Option<Signer>,
    rate_limiter: RateLimiter,
    ws_token: Option<String>,
}

#[derive(Debug, serde::Deserialize)]
pub struct IndodaxV1Response<T> {
    pub success: i32,
    #[serde(rename = "return")]
    pub return_data: Option<T>,
    pub error: Option<String>,
    pub error_code: Option<String>,
}

#[derive(Debug, serde::Deserialize)]
pub struct IndodaxV2Response<T> {
    pub data: Option<T>,
    pub code: Option<i64>,
    pub error: Option<String>,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct TvHistoryResponse {
    #[serde(rename = "t")]
    pub time: Vec<u64>,
    #[serde(rename = "o")]
    pub open: Vec<f64>,
    #[serde(rename = "h")]
    pub high: Vec<f64>,
    #[serde(rename = "l")]
    pub low: Vec<f64>,
    #[serde(rename = "c")]
    pub close: Vec<f64>,
    #[serde(rename = "v")]
    pub volume: Vec<f64>,
    #[serde(rename = "s")]
    pub status: String,
    #[serde(rename = "nextTime", skip_serializing_if = "Option::is_none")]
    pub next_time: Option<u64>,
}

impl IndodaxClient {
    pub fn new(signer: Option<Signer>) -> Result<Self, IndodaxError> {
        let builder = Client::builder();

        #[cfg(not(target_arch = "wasm32"))]
        let builder = builder
            .user_agent(format!("{}/{}", env!("CARGO_PKG_NAME"), env!("CARGO_PKG_VERSION")))
            .timeout(Duration::from_secs(30))
            .pool_max_idle_per_host(2);

        let http = builder
            .build()
            .map_err(|e| IndodaxError::Other(format!("Failed to create HTTP client: {}", e)))?;

        Ok(Self {
            http,
            signer,
            rate_limiter: RateLimiter::from_env(),
            ws_token: None,
        })
    }

    pub fn with_ws_token(mut self, token: Option<String>) -> Self {
        self.ws_token = token;
        self
    }

    pub fn signer(&self) -> Option<&Signer> {
        self.signer.as_ref()
    }

    pub fn ws_token(&self) -> Option<&str> {
        self.ws_token.as_deref()
    }

    pub fn http_client(&self) -> &Client {
        &self.http
    }

    pub async fn get_tradingview_history(
        &self,
        symbol: &str,
        timeframe: &str,
        from: u64,
        to: u64,
    ) -> Result<TvHistoryResponse, IndodaxError> {
        let from_str = from.to_string();
        let to_str = to.to_string();
        let params = [
            ("symbol", symbol),
            ("tf", timeframe),
            ("from", &from_str),
            ("to", &to_str),
        ];
        self.public_get_v2("/tradingview/history_v2", &params).await
    }

    pub async fn get_webdata(&self, pair: &str) -> Result<serde_json::Value, IndodaxError> {
        let path = format!("/api/webdata/{}", pair);
        self.public_get_v2(&path, &[("lang", "indonesia")]).await
    }

    pub async fn get_chatroom_history(&self) -> Result<serde_json::Value, IndodaxError> {
        self.public_get_v2("/api/v2/chatroom/history", &[]).await
    }

    pub async fn get_pairs_v2(&self, pair: Option<&str>) -> Result<serde_json::Value, IndodaxError> {
        if let Some(p) = pair {
            self.public_get_v2("/api/pairs_v2", &[("pair", p)]).await
        } else {
            self.public_get_v2("/api/pairs_v2", &[]).await
        }
    }

    pub async fn get_tv_search(&self) -> Result<serde_json::Value, IndodaxError> {
        self.public_get_v2("/tradingview/search_v2", &[]).await
    }

    pub async fn get_terminal_trade(&self, pair: &str) -> Result<serde_json::Value, IndodaxError> {
        let path = format!("/terminal-trading/trade?pair={}", pair);
        self.public_get_v2(&path, &[]).await
    }

    pub async fn get_terminal_market_data(&self, pair: &str) -> Result<serde_json::Value, IndodaxError> {
        let path = format!("/terminal-trading/market/data?pair={}", pair);
        self.public_get_v2(&path, &[]).await
    }

    pub async fn get_terminal_market_category(&self) -> Result<serde_json::Value, IndodaxError> {
        self.public_get_v2("/terminal-trading/market/category", &[]).await
    }

    pub async fn get_onramp_config(&self, pair: &str) -> Result<serde_json::Value, IndodaxError> {
        let url = format!("{}/deposit-idr/v1/onramp/config?pair={}", api_base_url(), pair);
        let resp = self.retry_get(&url).await?;
        self.handle_response(resp).await
    }

    pub async fn get_news(&self, asset: &str, page: u32) -> Result<String, IndodaxError> {
        let url = format!("{}/news?page={}&asset={}", public_base_url(), page, asset);
        let resp = self.retry_get(&url).await?;
        Ok(resp.text().await?)
    }

    pub async fn public_get<T: DeserializeOwned>(
        &self,
        path: &str,
    ) -> Result<T, IndodaxError> {
        let url = format!("{}{}", public_base_url(), path);
        let resp = self.retry_get(&url).await?;
        self.handle_response(resp).await
    }

    pub async fn countdown_cancel_all(
        &self,
        pair: Option<&str>,
        countdown_time: u64,
    ) -> Result<serde_json::Value, IndodaxError> {
        let signer = self.signer.as_ref().ok_or_else(|| {
            IndodaxError::Config("API credentials required for countdown cancel all".into())
        })?;

        let mut body_parts: Vec<String> = vec![
            format!("countdownTime={}", countdown_time),
        ];
        if let Some(p) = pair {
            body_parts.push(format!("pair={}", p));
        }

        let body = body_parts.join("&");
        let (payload, signature) = signer.sign_v1(&body)?;

        let url = format!("{}/countdownCancelAll", PRIVATE_V1_URL);
        let req = self
            .http
            .post(&url)
            .header("Key", signer.api_key())
            .header("Sign", &signature)
            .header("Content-Type", "application/x-www-form-urlencoded")
            .body(payload);
        let resp = self.send_with_retry(req).await?;
        self.handle_v1_response(resp).await
    }

    pub async fn generate_ws_token(&self) -> Result<(String, String), IndodaxError> {
        let signer = self.signer.as_ref().ok_or_else(|| {
            IndodaxError::Config("API credentials required for WebSocket token generation".into())
        })?;

        let nonce = signer.next_nonce_str();
        let (_, signature) = signer.sign_v1(&nonce)?;

        let req = self
            .http
            .post(WS_TOKEN_URL)
            .header("Key", signer.api_key())
            .header("Sign", &signature)
            .header("Content-Type", "application/x-www-form-urlencoded")
            .body(format!("nonce={}", nonce));
        let resp = self.send_with_retry(req).await?;

        let body_text = resp.text().await?;
        let val: serde_json::Value = serde_json::from_str(&body_text)?;

        let token = val.get("token")
            .and_then(|t| t.as_str())
            .or_else(|| val.get("data").and_then(|d| d.get("token")).and_then(|t| t.as_str()))
            .or_else(|| val.get("return").and_then(|r| r.get("connToken")).and_then(|t| t.as_str()))
            .map(|t| t.to_string());

        let channel = val.get("channel")
            .and_then(|c| c.as_str())
            .or_else(|| val.get("data").and_then(|d| d.get("channel")).and_then(|c| c.as_str()))
            .or_else(|| val.get("return").and_then(|r| r.get("channel")).and_then(|c| c.as_str()))
            .map(|c| c.to_string());

        match (token, channel) {
            (Some(t), Some(c)) => Ok((t, c)),
            (Some(t), None) => Ok((t, "private:orders".to_string())), // Fallback channel
            _ => Err(IndodaxError::WsToken(format!("No token or channel in response: {}", body_text))),
        }
    }

    pub async fn public_get_v2<T: DeserializeOwned>(
        &self,
        path: &str,
        params: &[(&str, &str)],
    ) -> Result<T, IndodaxError> {
        let url = format!("{}{}", public_base_url(), path);
        let resp = self.retry_get_with_params(&url, params).await?;
        self.handle_response(resp).await
    }

    async fn handle_v1_response<T: DeserializeOwned>(
        &self,
        resp: Response,
    ) -> Result<T, IndodaxError> {
        let body_text = resp.text().await?;
        let envelope: IndodaxV1Response<T> = serde_json::from_str(&body_text).map_err(|e| {
            IndodaxError::Parse(format!(
                "Failed to parse response: {} (body: {})",
                e, body_text
            ))
        })?;

        if envelope.success == 1 {
            envelope.return_data.ok_or_else(|| {
                IndodaxError::Parse("API returned success but no 'return' data".into())
            })
        } else {
            Err(IndodaxError::api(
                envelope.error.unwrap_or_else(|| "Unknown error".into()),
                match envelope.error_code.as_deref() {
                    Some("invalid_credentials") => ErrorCategory::Authentication,
                    Some("rate_limit") => ErrorCategory::RateLimit,
                    Some(c) if c.contains("invalid") => ErrorCategory::Validation,
                    _ => ErrorCategory::Unknown,
                },
                envelope.error_code,
            ))
        }
    }

    pub async fn private_post_v1<T: DeserializeOwned>(
        &self,
        method: &str,
        params: &HashMap<String, String>,
    ) -> Result<T, IndodaxError> {
        let signer = self.signer.as_ref().ok_or_else(|| {
            IndodaxError::Config("API credentials required for private endpoints".into())
        })?;

        let mut full_params: BTreeMap<String, String> = params
            .iter()
            .map(|(k, v)| (k.clone(), v.clone()))
            .collect();
        
        full_params.insert("method".into(), method.to_string());
        full_params.insert("nonce".into(), signer.next_nonce_str());

        let body = serde_urlencoded_str(&full_params);
        let (_, signature) = signer.sign_v1(&body)?;

        let resp = self
            .retry_post(PRIVATE_V1_URL, &body, signer.api_key(), &signature)
            .await?;

        self.handle_v1_response(resp).await
    }

    pub async fn private_get_v2<T: DeserializeOwned>(
        &self,
        path: &str,
        params: &HashMap<String, String>,
    ) -> Result<T, IndodaxError> {
        let signer = self.signer.as_ref().ok_or_else(|| {
            IndodaxError::Config("API credentials required for private endpoints".into())
        })?;

        let mut qs_parts: Vec<String> = params
            .iter()
            .map(|(k, v)| format!("{}={}", k, v))
            .collect();
        let timestamp = crate::now_millis();
        qs_parts.push(format!("timestamp={}", timestamp));
        qs_parts.push("recvWindow=5000".to_string());
        qs_parts.sort();
        let query_string = qs_parts.join("&");

        let signature = signer.sign_v2(&query_string)?;
        let url = format!("{}{}?{}", PRIVATE_V2_BASE, path, query_string);

        let req = self
            .http
            .get(&url)
            .header("X-APIKEY", signer.api_key())
            .header("Sign", &signature)
            .header("Accept", "application/json")
            .header("Content-Type", "application/json");
        let resp = self.send_with_retry(req).await?;

        let body_text = resp.text().await?;
        let envelope: IndodaxV2Response<T> = serde_json::from_str(&body_text).map_err(|e| {
            IndodaxError::Parse(format!(
                "Failed to parse v2 response: {} (body: {})",
                e, body_text
            ))
        })?;

        if let Some(data) = envelope.data {
            Ok(data)
        } else if let Some(error) = envelope.error {
            Err(IndodaxError::api(error, ErrorCategory::Unknown, None))
        } else {
            Ok(serde_json::from_str(&body_text)?)
        }
    }

    async fn retry_get(&self, url: &str) -> Result<Response, IndodaxError> {
        let req = self.http.get(url);
        self.send_with_retry(req).await
    }

    async fn retry_get_with_params(
        &self,
        url: &str,
        params: &[(&str, &str)],
    ) -> Result<Response, IndodaxError> {
        let req = self.http.get(url).query(params);
        self.send_with_retry(req).await
    }

    async fn retry_post(
        &self,
        url: &str,
        body: &str,
        api_key: &str,
        signature: &str,
    ) -> Result<Response, IndodaxError> {
        let req = self
            .http
            .post(url)
            .header("Key", api_key)
            .header("Sign", signature)
            .header("Content-Type", "application/x-www-form-urlencoded")
            .body(body.to_string());
        self.send_with_retry(req).await
    }

    async fn send_with_retry(
        &self,
        builder: RequestBuilder,
    ) -> Result<Response, IndodaxError> {
        self.rate_limiter.acquire().await;
        let mut last_err = None;
        let mut total_retries = 0u32;
        let mut backoff_count = 0u32;
        let mut current_builder = Some(builder);

        while total_retries <= MAX_RETRIES {
            if backoff_count > 0 {
                sleep(Duration::from_millis(500 * 2u64.pow(backoff_count - 1))).await;
            }

            let req = if total_retries == 0 {
                let b = current_builder.take().unwrap();
                current_builder = b.try_clone();
                b.build()
            } else {
                Ok(match &current_builder {
                    Some(b) => {
                        let retry_req = b.try_clone().map(|b| b.build());
                        match retry_req {
                            Some(Ok(r)) => r,
                            _ => return Err(last_err.unwrap_or_else(|| IndodaxError::Other("Request not cloneable for retry".into()))),
                        }
                    }
                    None => return Err(last_err.unwrap_or_else(|| IndodaxError::Other("Request not cloneable for retry".into()))),
                })
            }.map_err(|e| IndodaxError::Other(format!("Failed to build request: {}", e)))?;

            match self.http.execute(req).await {
                Ok(resp) => {
                    let status = resp.status();
                    if status.is_success() {
                        return Ok(resp);
                    }

                    if status == StatusCode::TOO_MANY_REQUESTS {
                        let retry_after = resp.headers()
                            .get("Retry-After")
                            .and_then(|v| v.to_str().ok())
                            .and_then(|s| s.parse::<u64>().ok())
                            .map(Duration::from_secs);
                        if let Some(delay) = retry_after {
                            sleep(delay).await;
                            backoff_count = 0;
                        } else {
                            backoff_count += 1;
                        }
                        total_retries += 1;
                        last_err = Some(IndodaxError::api(
                            format!("Rate limited (HTTP {})", status.as_u16()),
                            ErrorCategory::RateLimit,
                            None,
                        ));
                        
                        if current_builder.is_none() {
                             return Err(last_err.unwrap());
                        }
                        continue;
                    }

                    if status.is_server_error() {
                        total_retries += 1;
                        backoff_count += 1;
                        last_err = Some(IndodaxError::api(
                            format!("Server error (HTTP {})", status.as_u16()),
                            ErrorCategory::Server,
                            None,
                        ));
                        
                        if current_builder.is_none() {
                             return Err(last_err.unwrap());
                        }
                        continue;
                    }

                    last_err = Some(IndodaxError::api(
                        format!("HTTP {}", status.as_u16()),
                        ErrorCategory::Unknown,
                        None,
                    ));
                    break;
                }
                Err(e) => {
                    total_retries += 1;
                    backoff_count += 1;
                    
                    let is_retryable = e.is_timeout() || {
                        #[cfg(not(target_arch = "wasm32"))]
                        { e.is_connect() }
                        #[cfg(target_arch = "wasm32")]
                        { false }
                    };

                    if is_retryable && current_builder.is_some() {
                        last_err = Some(IndodaxError::Http(e));
                        continue;
                    }
                    
                    return Err(IndodaxError::Http(e));
                }
            }
        }

        Err(last_err.unwrap_or_else(|| {
            IndodaxError::Other("Max retries exceeded".into())
        }))
    }

    async fn handle_response<T: DeserializeOwned>(
        &self,
        resp: Response,
    ) -> Result<T, IndodaxError> {
        let body_text = resp.text().await?;
        serde_json::from_str(&body_text).map_err(|e| {
            IndodaxError::Parse(format!(
                "Failed to parse response: {} (body: {})",
                e, body_text
            ))
        })
    }
}

fn serde_urlencoded_str(params: &BTreeMap<String, String>) -> String {
    params
        .iter()
        .map(|(k, v)| {
            format!(
                "{}={}",
                url::form_urlencoded::byte_serialize(k.as_bytes()).collect::<String>(),
                url::form_urlencoded::byte_serialize(v.as_bytes()).collect::<String>()
            )
        })
        .collect::<Vec<_>>()
        .join("&")
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::auth::Signer;

    #[test]
    fn test_indodax_client_new_with_signer() {
        let signer = Signer::new("key", "secret");
        let client = IndodaxClient::new(Some(signer)).unwrap();
        assert!(client.signer().is_some());
    }

    #[test]
    fn test_indodax_client_new_without_signer() {
        let client = IndodaxClient::new(None).unwrap();
        assert!(client.signer().is_none());
    }

    #[test]
    fn test_indodax_client_signer() {
        let signer = Signer::new("mykey", "mysecret");
        let client = IndodaxClient::new(Some(signer)).unwrap();
        let s = client.signer().unwrap();
        assert_eq!(s.api_key(), "mykey");
    }

    #[test]
    fn test_indodax_v1_response_success() {
        let json = serde_json::json!({
            "success": 1,
            "return": {"balance": {"btc": "1.0"}},
            "error": null,
            "error_code": null
        });
        let resp: IndodaxV1Response<serde_json::Value> = serde_json::from_value(json).unwrap();
        assert_eq!(resp.success, 1);
        assert!(resp.return_data.is_some());
        assert!(resp.error.is_none());
    }

    #[test]
    fn test_indodax_v1_response_failure() {
        let json = serde_json::json!({
            "success": 0,
            "return": null,
            "error": "Invalid credentials",
            "error_code": "invalid_credentials"
        });
        let resp: IndodaxV1Response<serde_json::Value> = serde_json::from_value(json).unwrap();
        assert_eq!(resp.success, 0);
        assert!(resp.return_data.is_none());
        assert!(resp.error.is_some());
        assert!(resp.error_code.is_some());
    }

    #[test]
    fn test_indodax_v2_response_success() {
        let json = serde_json::json!({
            "data": {"name": "test"},
            "code": null,
            "error": null
        });
        let resp: IndodaxV2Response<serde_json::Value> = serde_json::from_value(json).unwrap();
        assert!(resp.data.is_some());
        assert!(resp.error.is_none());
    }

    #[test]
    fn test_indodax_v2_response_error() {
        let json = serde_json::json!({
            "data": null,
            "code": 400,
            "error": "Bad request"
        });
        let resp: IndodaxV2Response<serde_json::Value> = serde_json::from_value(json).unwrap();
        assert!(resp.data.is_none());
        assert!(resp.error.is_some());
        assert!(resp.code.is_some());
    }

    #[test]
    fn test_serde_urlencoded_str_single() {
        let mut params = std::collections::BTreeMap::new();
        params.insert("method".into(), "getInfo".into());
        params.insert("nonce".into(), "12345".into());
        
        let result = serde_urlencoded_str(&params);
        assert!(result.contains("method=getInfo"));
        assert!(result.contains("nonce=12345"));
    }

    #[test]
    fn test_serde_urlencoded_str_empty() {
        let params = std::collections::BTreeMap::new();
        let result = serde_urlencoded_str(&params);
        assert_eq!(result, "");
    }

    #[test]
    fn test_serde_urlencoded_str_special_chars() {
        let mut params = std::collections::BTreeMap::new();
        params.insert("key with space".into(), "value&more".into());
        
        let result = serde_urlencoded_str(&params);
        // Should be URL encoded
        assert!(result.contains("%20") || result.contains("+"));
    }

    #[test]
    fn test_public_base_url() {
        // In WASM mode, it might be a relative path like /api/indodax
        assert!(!public_base_url().is_empty());
    }

    #[test]
    fn test_private_v1_url() {
        assert!(PRIVATE_V1_URL.contains("indodax.com/tapi"));
    }

    #[test]
    fn test_private_v2_base() {
        assert!(PRIVATE_V2_BASE.contains("tapi.btcapi.net"));
    }

    #[test]
    fn test_max_retries_constant() {
        assert_eq!(MAX_RETRIES, 3);
    }

    #[test]
    fn test_indodax_v1_response_debug() {
        let resp: IndodaxV1Response<serde_json::Value> = IndodaxV1Response {
            success: 1,
            return_data: Some(serde_json::json!({})),
            error: None,
            error_code: None,
        };
        let debug_str = format!("{:?}", resp);
        assert!(debug_str.contains("success"));
    }

    #[test]
    fn test_indodax_v2_response_debug() {
        let resp: IndodaxV2Response<serde_json::Value> = IndodaxV2Response {
            data: Some(serde_json::json!({})),
            code: None,
            error: None,
        };
        let debug_str = format!("{:?}", resp);
        assert!(debug_str.contains("data"));
    }

    #[test]
    fn test_rate_limiter_from_env_default() {
        // Without env var, should default to 10
        let rl = RateLimiter::from_env();
        // If INDODAX_RATE_LIMIT is set in environment, test may fail
        // so we just verify it doesn't panic
        assert!(rl.capacity > 0);
        assert!(rl.refill_per_sec > 0);
    }

    #[tokio::test]
    async fn test_rate_limiter_acquire_single() {
        let rl = RateLimiter::new(5, 5);
        rl.acquire().await;
        let state = rl.state.lock().await;
        assert_eq!(state.tokens, 4);
    }

    #[tokio::test]
    async fn test_rate_limiter_token_exhaustion_refills() {
        let rl = RateLimiter::new(3, 10);
        for _ in 0..3 {
            rl.acquire().await;
        }
        {
            let state = rl.state.lock().await;
            assert_eq!(state.tokens, 0);
        }

        {
            let mut state = rl.state.lock().await;
            state.last_refill = Instant::now() - Duration::from_secs(1);
        }

        rl.acquire().await;
        let state = rl.state.lock().await;
        assert_eq!(state.tokens, 2);
    }

    #[tokio::test]
    async fn test_rate_limiter_refill_capped_at_capacity() {
        let rl = RateLimiter::new(5, 100);
        for _ in 0..5 {
            rl.acquire().await;
        }
        {
            let state = rl.state.lock().await;
            assert_eq!(state.tokens, 0);
        }

        {
            let mut state = rl.state.lock().await;
            state.last_refill = Instant::now() - Duration::from_secs(10);
        }

        rl.acquire().await;
        let state = rl.state.lock().await;
        assert_eq!(state.tokens, 4);
    }

    #[test]
    fn test_rate_limiter_new_custom() {
        let rl = RateLimiter::new(25, 25);
        assert_eq!(rl.capacity, 25);
        assert_eq!(rl.refill_per_sec, 25);
    }
}