Function send_message_inner

src-tauri/src/services/chat_service.rs:243–375

(
    db: &SqlitePool,
    session_id: &str,
    content: &str,
    provider_id: Option<&str>,
    model_id: Option<&str>,
    on_token: Channel<String>,
    app_handle: &AppHandle,
    cancel_token: 

#[allow(clippy::too_many_arguments)]
async fn send_message_inner(
    db: &SqlitePool,
    session_id: &str,
    content: &str,
    provider_id: Option<&str>,
    model_id: Option<&str>,
    on_token: Channel<String>,
    app_handle: &AppHandle,
    cancel_token: CancellationToken,
) -> AppResult<()> {
    let normalized = content.trim();
    if normalized.is_empty() {
        return Err(AppError::Validation(
            "Message content cannot be empty".to_string(),
        ));
    }

    let user_message = Message {
        id: Uuid::new_v4().to_string(),
        session_id: session_id.to_string(),
        role: "user".to_string(),
        content: normalized.to_string(),
        created_at: now_rfc3339(),
    };

    sqlx::query(
        "INSERT INTO messages (id, session_id, role, content, created_at) VALUES (?1, ?2, ?3, ?4, ?5)",
    )
    .bind(&user_message.id)
    .bind(&user_message.session_id)
    .bind(&user_message.role)
    .bind(&user_message.content)
    .bind(&user_message.created_at)
    .execute(db)
    .await?;

    let provider = provider_service::get_provider_for_chat(db, provider_id).await?;

    // Pre-flight: check API key is configured (except for local providers like Ollama)
    if provider.provider_type != "ollama"
        && provider
            .api_key
            .as_deref()
            .is_none_or(|k| k.trim().is_empty())
    {
        return Err(AppError::Validation(format!(
            "API key not configured for '{}'. Go to Settings → Providers and enter your API key.",
            provider.name
        )));
    }

    let raw_history = get_messages(db, session_id).await?;
    let history = trim_history_for_llm(&raw_history);

    // Debug: log context size so token bloat is easy to spot
    let total_chars: usize = history.iter().map(|m| m.content.len()).sum();
    let est_tokens = total_chars / 4; // rough estimate: 1 token ≈ 4 chars
    log::debug!(