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cairn_cli/
client.rs

1use reqwest::header::{HeaderMap, HeaderValue, AUTHORIZATION, CONTENT_TYPE};
2use serde_json::Value;
3
4use crate::config::{CairnConfig, Credentials};
5use crate::errors::CairnError;
6
7/// HTTP client wrapper with automatic JWT injection and x402 payment fallback.
8pub struct BackpacClient {
9    inner: reqwest::Client,
10    base_url: String,
11    jwt: Option<String>,
12}
13
14impl BackpacClient {
15    /// Create a new client. Reads JWT from env, flag, or saved credentials.
16    pub fn new(jwt_override: Option<&str>, api_url: Option<&str>) -> Self {
17        let config = CairnConfig::load();
18
19        let base_url = api_url
20            .map(|s| s.to_string())
21            .or(config.api_url.clone())
22            .or_else(|| std::env::var("BACKPAC_API_URL").ok())
23            .unwrap_or_else(|| "https://api.backpac.xyz".to_string());
24
25        let jwt = jwt_override
26            .map(|s| s.to_string())
27            .or_else(|| std::env::var("BACKPAC_JWT").ok())
28            .or_else(|| Credentials::load().map(|c| c.jwt));
29
30        let inner = reqwest::Client::builder()
31            .timeout(std::time::Duration::from_secs(30))
32            .build()
33            .expect("Failed to create HTTP client");
34
35        Self { inner, base_url, jwt }
36    }
37
38    /// Build headers with JWT Bearer auth.
39    fn auth_headers(&self) -> Result<HeaderMap, CairnError> {
40        let mut headers = HeaderMap::new();
41        headers.insert(CONTENT_TYPE, HeaderValue::from_static("application/json"));
42
43        if let Some(ref jwt) = self.jwt {
44            let val = format!("Bearer {}", jwt);
45            headers.insert(
46                AUTHORIZATION,
47                HeaderValue::from_str(&val).map_err(|e| CairnError::Auth(e.to_string()))?,
48            );
49        }
50        Ok(headers)
51    }
52
53    /// GET request with auth.
54    pub async fn get(&self, path: &str) -> Result<Value, CairnError> {
55        let url = format!("{}{}", self.base_url, path);
56        let resp = self
57            .inner
58            .get(&url)
59            .headers(self.auth_headers()?)
60            .send()
61            .await?;
62
63        self.handle_response(resp).await
64    }
65
66    /// POST request with auth and JSON body.
67    pub async fn post(&self, path: &str, body: &Value) -> Result<Value, CairnError> {
68        let url = format!("{}{}", self.base_url, path);
69        let resp = self
70            .inner
71            .post(&url)
72            .headers(self.auth_headers()?)
73            .json(body)
74            .send()
75            .await?;
76
77        self.handle_response(resp).await
78    }
79
80    /// PUT request with auth and JSON body.
81    pub async fn put(&self, path: &str, body: &Value) -> Result<Value, CairnError> {
82        let url = format!("{}{}", self.base_url, path);
83        let resp = self
84            .inner
85            .put(&url)
86            .headers(self.auth_headers()?)
87            .json(body)
88            .send()
89            .await?;
90
91        self.handle_response(resp).await
92    }
93
94    /// POST for RPC route (root path /) with custom headers for PoI binding.
95    pub async fn rpc_post(
96        &self,
97        body: &Value,
98        poi_id: Option<&str>,
99        confidence: Option<f64>,
100    ) -> Result<Value, CairnError> {
101        let url = format!("{}/", self.base_url);
102        let mut headers = self.auth_headers()?;
103
104        if let Some(poi) = poi_id {
105            headers.insert(
106                "X-Backpac-Poi-Id",
107                HeaderValue::from_str(poi).map_err(|e| CairnError::InvalidInput(e.to_string()))?,
108            );
109        }
110        if let Some(conf) = confidence {
111            headers.insert(
112                "X-Backpac-Confidence",
113                HeaderValue::from_str(&conf.to_string())
114                    .map_err(|e| CairnError::InvalidInput(e.to_string()))?,
115            );
116        }
117
118        let resp = self.inner.post(&url).headers(headers).json(body).send().await?;
119        self.handle_response(resp).await
120    }
121
122    /// Handle HTTP response, mapping status codes to CairnErrors.
123    async fn handle_response(&self, resp: reqwest::Response) -> Result<Value, CairnError> {
124        let status = resp.status();
125
126        if status.is_success() {
127            let body: Value = resp.json().await?;
128            return Ok(body);
129        }
130
131        // Try to parse error body
132        let body_text = resp.text().await.unwrap_or_default();
133        let error_msg = serde_json::from_str::<Value>(&body_text)
134            .ok()
135            .and_then(|v| v.get("error").and_then(|e| e.as_str()).map(String::from))
136            .unwrap_or_else(|| body_text.clone());
137
138        match status.as_u16() {
139            400 => Err(CairnError::InvalidInput(error_msg)),
140            401 => {
141                if error_msg.contains("expired") {
142                    Err(CairnError::TokenExpired)
143                } else {
144                    Err(CairnError::Auth(error_msg))
145                }
146            }
147            402 => {
148                // x402 Payment Required — attempt auto-payment
149                // TODO: Implement full x402 auto-retry with wallet signing
150                Err(CairnError::InsufficientFunds(
151                    "Credits exhausted. x402 auto-payment not yet implemented.".to_string(),
152                ))
153            }
154            403 => Err(CairnError::Auth(error_msg)),
155            404 => Err(CairnError::NotFound(error_msg)),
156            409 => Err(CairnError::Conflict(error_msg)),
157            410 => {
158                if error_msg.contains("expired") {
159                    Err(CairnError::IntentExpired(error_msg))
160                } else {
161                    Err(CairnError::IntentAborted(error_msg))
162                }
163            }
164            _ => Err(CairnError::General(format!("HTTP {}: {}", status, error_msg))),
165        }
166    }
167}