use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Conversation {
    pub messages: Vec<crate::dto::chat::message::ChatMessage>,
    pub system_prompt: String,
    pub session_id: String,
    pub model: String,
    pub max_tokens: u32,
    pub temperature: f32,
}

impl Conversation {
    pub fn new(system_prompt: String, session_id: String) -> Self {
        Conversation {
            messages: Vec::new(),
            system_prompt,
            session_id,
            model: "anthropic/claude-opus-4-8".to_string(),
            max_tokens: 8192,
            temperature: 0.7,
        }
    }

    pub fn push(&mut self, msg: crate::dto::chat::message::ChatMessage) {
        self.messages.push(msg);
    }

    pub fn rebuild_system(&mut self, new_prompt: String) {
        self.system_prompt = new_prompt;
        self.messages.retain(|m| {
            !matches!(m.role, crate::dto::chat::message::Role::System)
        });
    }

    pub fn to_api_messages(&self) -> Vec<crate::dto::chat::message::ChatMessage> {
        let mut msgs = Vec::with_capacity(self.messages.len() + 1);
        msgs.push(crate::dto::chat::message::ChatMessage::system(&self.system_prompt));
        msgs.extend(self.messages.iter().cloned());
        msgs
    }

    pub fn len(&self) -> usize {
        self.messages.len()
    }
}