feat: add `config.prelude` to allow setting default role/session (#224)

6 files changed, 34 insertions, 6 deletions

diff --git a/README.md b/README.md
index a061bf2..df4ed18 100644
--- a/README.md
+++ b/README.md
@@ -68,6 +68,7 @@ wrap: no                         # Specify the text-wrapping mode (no, auto, <ma
 wrap_code: false                 # Whether wrap code block
 auto_copy: false                 # Automatically copy the last output to the clipboard
 keybindings: emacs               # REPL keybindings. values: emacs, vi
+prelude: ''                      # Set a default role or session (role:<name>, session:<name>)
 
 clients:
   - type: openai
@@ -141,7 +142,7 @@ The Chat REPL supports:
 .info                    Print system info
 .edit                    Multi-line editing (CTRL+S to finish)
 .model                   Switch LLM model
-.role                    Use role
+.role                    Use a role
 .info role               Show role info
 .exit role               Leave current role
 .session                 Start a context-aware chat session
diff --git a/config.example.yaml b/config.example.yaml
index 30e00c9..8eae76b 100644
--- a/config.example.yaml
+++ b/config.example.yaml
@@ -6,7 +6,8 @@ light_theme: false               # Whether to use a light theme
 wrap: no                         # Specify the text-wrapping mode (no, auto, <max-width>)
 wrap_code: false                 # Whether wrap code block
 auto_copy: false                 # Automatically copy the last output to the clipboard
-keybindings: emacs               # REPL keybindings. values: emacs, vi
+keybindings: emacs               # REPL keybindings. (emacs, vi)
+prelude: ''                      # Set a default role or session (role:<name>, session:<name>)
 
 clients:
   # All clients have the following configuration:
diff --git a/src/config/mod.rs b/src/config/mod.rs
index e6fef5f..22c58bb 100644
--- a/src/config/mod.rs
+++ b/src/config/mod.rs
@@ -60,9 +60,11 @@ pub struct Config {
     pub wrap_code: bool,
     /// Automatically copy the last output to the clipboard
     pub auto_copy: bool,
-    /// REPL keybindings. values: emacs, vi
+    /// REPL keybindings. (emacs, vi)
     pub keybindings: Keybindings,
-    /// Setup AIs
+    /// Set a default role or session (role:<name>, session:<name>)
+    pub prelude: String,
+    /// Setup clients
     pub clients: Vec<ClientConfig>,
     /// Predefined roles
     #[serde(skip)]
@@ -94,6 +96,7 @@ impl Default for Config {
             wrap_code: false,
             auto_copy: false,
             keybindings: Default::default(),
+            prelude: String::new(),
             clients: vec![ClientConfig::default()],
             roles: vec![],
             role: None,
@@ -145,6 +148,28 @@ impl Config {
         Ok(config)
     }
 
+    pub fn onstart(&mut self) -> Result<()> {
+        let prelude = self.prelude.clone();
+        let err_msg = || format!("Invalid prelude '{}", prelude);
+        match prelude.split_once(':') {
+            Some(("role", name)) => {
+                if self.role.is_none() && self.session.is_none() {
+                    self.set_role(name).with_context(err_msg)?;
+                }
+            }
+            Some(("session", name)) => {
+                if self.session.is_none() {
+                    self.start_session(Some(name)).with_context(err_msg)?;
+                }
+            }
+            Some(_) => {
+                bail!("{}", err_msg())
+            }
+            None => {}
+        }
+        Ok(())
+    }
+
     pub fn retrieve_role(&self, name: &str) -> Result<Role> {
         self.roles
             .iter()
diff --git a/src/main.rs b/src/main.rs
index a40745f..368779e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -77,6 +77,7 @@ fn main() -> Result<()> {
         println!("{}", info);
         exit(0);
     }
+    config.write().onstart()?;
     let no_stream = cli.no_stream;
     let client = init_client(&config)?;
     if stdin().is_terminal() {
diff --git a/src/render/repl.rs b/src/render/repl.rs
index 34212c3..ca11e17 100644
--- a/src/render/repl.rs
+++ b/src/render/repl.rs
@@ -83,7 +83,7 @@ fn repl_render_stream_inner(
                         queue!(writer, style::Print(&buffer),)?;
 
                         // No guarantee the buffer width of the buffer will not exceed the number of columns.
-                        // So we calcuate the number of rows needed, rather than setting it directly to 1.
+                        // So we calculate the number of rows needed, rather than setting it directly to 1.
                         buffer_rows = need_rows(&buffer, columns);
                     } else {
                         buffer = format!("{buffer}{text}");
diff --git a/src/repl/mod.rs b/src/repl/mod.rs
index 3962229..a4f397c 100644
--- a/src/repl/mod.rs
+++ b/src/repl/mod.rs
@@ -32,7 +32,7 @@ const REPL_COMMANDS: [(&str, &str); 14] = [
     (".info", "Print system info"),
     (".edit", "Multi-line editing (CTRL+S to finish)"),
     (".model", "Switch LLM model"),
-    (".role", "Use role"),
+    (".role", "Use a role"),
     (".info role", "Show role info"),
     (".exit role", "Leave current role"),
     (".session", "Start a context-aware chat session"),