quick wins (issues #9 #10 #11 #12 #13 #16) : am logs (tail+follow), am list --running/--sort, am config set, am alias add/remove/list, dedup historique, am open

src/commands/logs_cmd.rs

@@ -0,0 +1,56 @@
+//! logs: tail the log file of an agent (--follow for a live view).
+
+use super::*;
+use crate::output::print_json;
+use anyhow::{bail, Result};
+use std::path::PathBuf;
+
+/// Resolve the log path of an agent (validates the agent first).
+pub fn log_path(app: &App, agent_name: &str) -> Result<PathBuf> {
+    let agent = require_agent(app, agent_name)?;
+    Ok(crate::process::agent_log_path(app, &agent.name))
+}
+
+pub fn run(app: &App, agent: &str, lines: usize, follow: bool) -> Result<i32> {
+    let path = log_path(app, agent)?;
+    if !path.exists() {
+        bail!(
+            "no log yet for '{}' — start it with 'am start {} --background'",
+            agent,
+            agent
+        );
+    }
+    if app.json() {
+        let tail = crate::process::last_lines(&path, lines);
+        print_json(&serde_json::json!({
+            "agent": agent,
+            "log": path.display().to_string(),
+            "tail": tail,
+        }));
+        return Ok(0);
+    }
+    if !follow {
+        print!("{}", crate::process::last_lines(&path, lines));
+        return Ok(0);
+    }
+    // Live follow: print the initial tail, then new bytes as they arrive.
+    let mut seen: usize = std::fs::metadata(&path).map(|m| m.len() as usize).unwrap_or(0);
+    loop {
+        if let Ok(text) = std::fs::read_to_string(&path) {
+            let bytes = text.as_bytes();
+            if bytes.len() > seen {
+                // Slicer sans risque de couper un caractere UTF-8.
+                let tail: String = text
+                    .char_indices()
+                    .filter(|(i, _)| *i >= seen)
+                    .map(|(_, c)| c)
+                    .collect();
+                print!("{tail}");
+                use std::io::Write;
+                let _ = std::io::stdout().flush();
+            }
+            seen = bytes.len();
+        }
+        std::thread::sleep(std::time::Duration::from_secs(1));
+    }
+}