Implement file information processing queue system and Vector Graph preperation

rust-engine/src/gemini_client.rs

@@ -1,5 +1,7 @@
 use anyhow::Result;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
+use serde_json::json;
+use reqwest::Client;
 
 // NOTE: This is a small stub to represent where you'd call the Gemini API.
 // Replace with real API call and proper auth handling for production.
@@ -35,3 +37,52 @@ pub async fn demo_text_embedding(text: &str) -> Result<Vec<f32>> {
     }
     Ok(v)
 }
+
+/// Generate text with Gemini (Generative Language API). Falls back to a demo string if GEMINI_API_KEY is not set.
+pub async fn generate_text(prompt: &str) -> Result<String> {
+    let api_key = match std::env::var("GEMINI_API_KEY") {
+        Ok(k) if !k.is_empty() => k,
+        _ => {
+            return Ok(format!("[demo] Gemini not configured. Prompt preview: {}", truncate(prompt, 240)));
+        }
+    };
+
+    let model = std::env::var("GEMINI_MODEL").unwrap_or_else(|_| "gemini-1.5-pro".to_string());
+    let url = format!(
+        "https://generativelanguage.googleapis.com/v1beta/models/{}:generateContent?key={}",
+        model, api_key
+    );
+
+    let body = json!({
+        "contents": [ { "parts": [ { "text": prompt } ] } ]
+    });
+
+    let client = Client::new();
+    let resp = client.post(&url).json(&body).send().await?;
+    let status = resp.status();
+    let txt = resp.text().await?;
+    if !status.is_success() {
+        return Ok(format!("[demo] Gemini error {}: {}", status, truncate(&txt, 240)));
+    }
+
+    #[derive(Deserialize)]
+    struct Part { text: Option<String> }
+    #[derive(Deserialize)]
+    struct Content { parts: Vec<Part> }
+    #[derive(Deserialize)]
+    struct Candidate { content: Content }
+    #[derive(Deserialize)]
+    struct Response { candidates: Option<Vec<Candidate>> }
+
+    let data: Response = serde_json::from_str(&txt).unwrap_or(Response { candidates: None });
+    let out = data
+        .candidates
+        .and_then(|mut v| v.pop())
+        .and_then(|c| c.content.parts.into_iter().find_map(|p| p.text))
+        .unwrap_or_else(|| "[demo] Gemini returned empty response".to_string());
+    Ok(out)
+}
+
+fn truncate(s: &str, max: usize) -> String {
+    if s.len() <= max { s.to_string() } else { format!("{}…", &s[..max]) }
+}