Write a .mambarc on first use

Signed-off-by: Rick Elrod <rick.elrod@checkmk.com>

Author: relrod

Cargo.lock

@@ -5,3 +5,5 @@ edition = "2024"
 
 [dependencies]
 clap = { version = "4.5.50", features = ["derive", "wrap_help"] }
+env_logger = "0.11.8"
+log = "0.4.28"

Cargo.toml

@@ -2,6 +2,10 @@ mod env;
 mod robot;
 
 use clap::{Parser, Subcommand};
+use log::debug;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
 
 #[derive(Parser, Debug)]
 #[command(version)]
@@ -23,9 +27,39 @@ enum Command {
 }
 
 fn main() {
+    env_logger::init();
+    let _ = create_mambarc();
     let cli = Cli::parse();
     match cli.command {
         Command::Env(sub) => env::run(sub),
         Command::Robot(sub) => robot::run(sub),
     }
 }
+
+fn create_mambarc() -> std::io::Result<()> {
+    let mambarc = r#"
+# Show the active environment in the shell prompt
+changeps1: True
+
+# proxy_servers:
+#   http: http://user:pass@corp.com:8080_
+#   https: https://user:pass@corp.com:8080_
+
+# Use this only if you are behind a proxy that does SSL inspection
+# ssl_verify: false
+# ssl_verify: mycorpcert.crt
+# ssl_no_revoke: true
+"#;
+    let home = std::env::var("HOME")
+        .or_else(|_| std::env::var("USERPROFILE"))
+        .expect("Cannot determine home directory");
+    let mambarc_path = PathBuf::from(home).join(".mambarc");
+    match File::create_new(&mambarc_path) {
+        Ok(mut file) => file.write_all(mambarc.trim_start().as_bytes())?,
+        Err(e) if e.kind() == std::io::ErrorKind::AlreadyExists => {
+            debug!("File {mambarc_path:?} already exists, not creating")
+        }
+        Err(e) => return Err(e),
+    }
+    Ok(())
+}