feat: support multiple models

src/cli.rs

@@ -3,6 +3,9 @@ use clap::Parser;
 #[derive(Parser, Debug)]
 #[command(author, version, about, long_about = None)]
 pub struct Cli {
+    /// Choose a model
+    #[clap(short, long)]
+    pub model: Option<String>,
     /// Add a GPT prompt
     #[clap(short, long)]
     pub prompt: Option<String>,
@@ -15,6 +18,9 @@ pub struct Cli {
     /// List all roles
     #[clap(long)]
     pub list_roles: bool,
+    /// List all models
+    #[clap(long)]
+    pub list_models: bool,
     /// Select a role
     #[clap(short, long)]
     pub role: Option<String>,

src/client.rs

@@ -12,7 +12,6 @@ use tokio::time::sleep;
 
 const CONNECT_TIMEOUT: Duration = Duration::from_secs(10);
 const API_URL: &str = "https://api.openai.com/v1/chat/completions";
-const MODEL: &str = "gpt-3.5-turbo";
 
 #[derive(Debug)]
 pub struct ChatGptClient {
@@ -137,9 +136,10 @@ impl ChatGptClient {
     }
 
     fn request_builder(&self, content: &str, stream: bool) -> Result<RequestBuilder> {
+        let (model, _) = self.config.read().get_model();
         let messages = self.config.read().build_messages(content)?;
         let mut body = json!({
-            "model": MODEL,
+            "model": model,
             "messages": messages,
         });
 

src/config/conversation.rs

@@ -1,4 +1,4 @@
-use super::message::{num_tokens_from_messages, Message, MessageRole, MAX_TOKENS};
+use super::message::{num_tokens_from_messages, Message, MessageRole};
 use super::role::Role;
 
 use anyhow::{bail, Result};
@@ -87,8 +87,4 @@ impl Conversation {
         }
         messages
     }
-
-    pub fn reamind_tokens(&self) -> usize {
-        MAX_TOKENS.saturating_sub(self.tokens)
-    }
 }

src/config/message.rs

@@ -3,8 +3,6 @@ use crate::utils::count_tokens;
 use anyhow::{bail, Result};
 use serde::{Deserialize, Serialize};
 
-pub const MAX_TOKENS: usize = 4096;
-
 #[derive(Debug, Clone, Deserialize, Serialize)]
 pub struct Message {
     pub role: MessageRole,
@@ -28,9 +26,9 @@ pub enum MessageRole {
     User,
 }
 
-pub fn within_max_tokens_limit(messages: &[Message]) -> Result<()> {
+pub fn within_max_tokens_limit(messages: &[Message], max_tokens: usize) -> Result<()> {
     let tokens = num_tokens_from_messages(messages);
-    if tokens >= MAX_TOKENS {
+    if tokens >= max_tokens {
         bail!("Exceed max tokens limit")
     }
     Ok(())

src/config/mod.rs

@@ -21,6 +21,12 @@ use std::{
     sync::Arc,
 };
 
+pub const MODELS: [(&str, usize); 3] = [
+    ("gpt-4", 8192),
+    ("gpt-4-32k", 32768),
+    ("gpt-3.5-turbo", 4096),
+];
+
 const CONFIG_FILE_NAME: &str = "config.yaml";
 const ROLES_FILE_NAME: &str = "roles.yaml";
 const HISTORY_FILE_NAME: &str = "history.txt";
@@ -42,6 +48,9 @@ const SET_COMPLETIONS: [&str; 9] = [
 pub struct Config {
     /// Openai api key
     pub api_key: Option<String>,
+    /// Openai model
+    #[serde(rename(serialize = "model", deserialize = "model"))]
+    pub model_name: Option<String>,
     /// What sampling temperature to use, between 0 and 2
     pub temperature: Option<f64>,
     /// Whether to persistently save chat messages
@@ -65,12 +74,15 @@ pub struct Config {
     /// Current conversation
     #[serde(skip)]
     pub conversation: Option<Conversation>,
+    #[serde(skip)]
+    pub model: (String, usize),
 }
 
 impl Default for Config {
     fn default() -> Self {
         Self {
             api_key: None,
+            model_name: None,
             temperature: None,
             save: false,
             highlight: true,
@@ -81,6 +93,7 @@ impl Default for Config {
             roles: vec![],
             role: None,
             conversation: None,
+            model: ("gpt-3.5-turbo".into(), 4096),
         }
     }
 }
@@ -105,6 +118,9 @@ impl Config {
         if config.api_key.is_none() {
             bail!("api_key not set");
         }
+        if let Some(name) = config.model_name.clone() {
+            config.set_model(&name)?;
+        }
         config.merge_env_vars();
         config.maybe_proxy();
         config.load_roles()?;
@@ -251,6 +267,10 @@ impl Config {
         }
     }
 
+    pub fn get_model(&self) -> (String, usize) {
+        self.model.clone()
+    }
+
     pub fn build_messages(&self, content: &str) -> Result<Vec<Message>> {
         let messages = if let Some(conversation) = self.conversation.as_ref() {
             conversation.build_emssages(content)
@@ -260,11 +280,28 @@ impl Config {
             let message = Message::new(content);
             vec![message]
         };
-        within_max_tokens_limit(&messages)?;
+        within_max_tokens_limit(&messages, self.model.1)?;
 
         Ok(messages)
     }
 
+    pub fn set_model(&mut self, name: &str) -> Result<()> {
+        if let Some(token) = MODELS.iter().find(|(v, _)| *v == name).map(|(_, v)| *v) {
+            self.model = (name.to_string(), token);
+        } else {
+            bail!("Invalid model")
+        }
+        Ok(())
+    }
+
+    pub fn get_reamind_tokens(&self) -> usize {
+        let mut tokens = self.model.1;
+        if let Some(conversation) = self.conversation.as_ref() {
+            tokens = tokens.saturating_sub(conversation.tokens);
+        }
+        tokens
+    }
+
     pub fn info(&self) -> Result<String> {
         let file_info = |path: &Path| {
             let state = if path.exists() { "" } else { " ⚠️" };
@@ -284,6 +321,7 @@ impl Config {
             ("roles_file", file_info(&Config::roles_file()?)),
             ("messages_file", file_info(&Config::messages_file()?)),
             ("api_key", self.get_api_key().to_string()),
+            ("model", self.model.0.to_string()),
             ("temperature", temperature),
             ("save", self.save.to_string()),
             ("highlight", self.highlight.to_string()),
@@ -307,6 +345,7 @@ impl Config {
             .collect();
 
         completion.extend(SET_COMPLETIONS.map(|v| v.to_string()));
+        completion.extend(MODELS.map(|(v, _)| format!(".model {}", v)));
         completion
     }
 
@@ -359,14 +398,12 @@ impl Config {
     }
 
     pub fn start_conversation(&mut self) -> Result<()> {
-        if let Some(conversation) = self.conversation.as_ref() {
-            if conversation.reamind_tokens() > 0 {
-                let ans = Confirm::new("Already in a conversation, start a new one?")
-                    .with_default(true)
-                    .prompt()?;
-                if !ans {
-                    return Ok(());
-                }
+        if self.conversation.is_some() && self.get_reamind_tokens() > 0 {
+            let ans = Confirm::new("Already in a conversation, start a new one?")
+                .with_default(true)
+                .prompt()?;
+            if !ans {
+                return Ok(());
             }
         }
         self.conversation = Some(Conversation::new(self.role.clone()));

src/main.rs

@@ -35,6 +35,12 @@ fn main() -> Result<()> {
             .for_each(|v| println!("{}", v.name));
         exit(0);
     }
+    if cli.list_models {
+        config::MODELS
+            .iter()
+            .for_each(|(name, _)| println!("{}", name));
+        exit(0);
+    }
     let role = match &cli.role {
         Some(name) => Some(
             config
@@ -44,6 +50,9 @@ fn main() -> Result<()> {
         ),
         None => None,
     };
+    if let Some(model) = &cli.model {
+        config.write().set_model(model)?;
+    }
     config.write().role = role;
     if cli.no_highlight {
         config.write().highlight = false;

src/repl/handler.rs

@@ -12,6 +12,7 @@ use std::cell::RefCell;
 
 pub enum ReplCmd {
     Submit(String),
+    SetModel(String),
     SetRole(String),
     UpdateConfig(String),
     Prompt(String),
@@ -65,6 +66,10 @@ impl ReplCmdHandler {
                 self.config.write().save_conversation(&input, &buffer)?;
                 *self.reply.borrow_mut() = buffer;
             }
+            ReplCmd::SetModel(name) => {
+                self.config.write().set_model(&name)?;
+                print_now!("\n");
+            }
             ReplCmd::SetRole(name) => {
                 let output = self.config.write().change_role(&name)?;
                 print_now!("{}\n\n", output.trim_end());

src/repl/mod.rs

@@ -19,9 +19,10 @@ use reedline::Signal;
 use std::borrow::Cow;
 use std::sync::Arc;
 
-pub const REPL_COMMANDS: [(&str, &str); 11] = [
+pub const REPL_COMMANDS: [(&str, &str); 12] = [
     (".info", "Print the information"),
     (".set", "Modify the configuration temporarily"),
+    (".model", "Choose a model"),
     (".prompt", "Add a GPT prompt"),
     (".role", "Select a role"),
     (".clear role", "Clear the currently selected role"),
@@ -109,6 +110,10 @@ impl Repl {
                     self.editor.print_history()?;
                     print_now!("\n");
                 }
+                ".model" => match args {
+                    Some(name) => handler.handle(ReplCmd::SetModel(name.to_string()))?,
+                    None => print_now!("Usage: .model <name>\n\n"),
+                },
                 ".role" => match args {
                     Some(name) => handler.handle(ReplCmd::SetRole(name.to_string()))?,
                     None => print_now!("Usage: .role <name>\n\n"),

src/repl/prompt.rs

@@ -76,10 +76,10 @@ impl Prompt for ReplPrompt {
     }
 
     fn render_prompt_right(&self) -> Cow<str> {
-        if let Some(conversation) = self.config.read().conversation.as_ref() {
-            conversation.reamind_tokens().to_string().into()
-        } else {
+        if self.config.read().conversation.is_none() {
             Cow::Borrowed("")
+        } else {
+            self.config.read().get_reamind_tokens().to_string().into()
         }
     }