//! JSON file–backed `ConversationRepository`.
//! Stores `Conversation` at `<session_dir>/conversation.json`.

use std::path::Path;

use zesdex_domain::cms::{Conversation, ConversationRepository, RepositoryError};

use crate::utils::write_json_atomic;

/// File-based `ConversationRepository` that reads/writes `conversation.json`.
#[derive(Debug, Clone, Default)]
pub struct JsonConversationRepository;

impl JsonConversationRepository {
    pub fn new() -> Self {
        Self
    }
}

impl ConversationRepository for JsonConversationRepository {
    fn load(&self, session_dir: &Path) -> Result<Conversation, RepositoryError> {
        let path = session_dir.join("conversation.json");
        let data = std::fs::read_to_string(&path)?;
        let conv: Conversation = serde_json::from_str(&data)?;
        Ok(conv)
    }

    fn save(&self, session_dir: &Path, conversation: &Conversation) -> Result<(), RepositoryError> {
        std::fs::create_dir_all(session_dir)?;
        let path = session_dir.join("conversation.json");
        write_json_atomic(&path, conversation, None)?;
        Ok(())
    }
}