// --- Declare our new modules ---
mod config;
mod parser;

// --- External Crates ---
use pyo3::prelude::*;
use pyo3::exceptions::PyValueError;
use tokio;
use pyo3::types::{PyModule, PyAny};
use pyo3::Bound;
use pyo3_arrow::PyRecordBatch;

// Use the high-performance mimalloc for better multi-threaded memory allocation.
// We conditionally compile it to avoid issues on MSVC targets.
#[cfg(not(target_env = "msvc"))]
use mimalloc;

#[cfg(not(target_env = "msvc"))]
#[global_allocator]
static GLOBAL: mimalloc::MiMalloc = mimalloc::MiMalloc;

// --- Internal Crates ---
use crate::config::{load_and_validate_config, ConnectorConfig};
use crate::parser::run_db_logic;


// --- THE PYTHON-CALLABLE ENTRY POINT ---

#[pyfunction]
#[pyo3(signature = (config_path, blast_radius=312500))]
#[allow(unsafe_code)]
#[allow(unsafe_op_in_unsafe_fn)]
#[allow(rust_2024_compatibility)]
fn load_data_from_config<'py>(
    py: Python<'py>,
    config_path: String,
    blast_radius: i64,
) -> PyResult<Bound<'py, PyAny>> {

    // --- Phase 1: Load and Validate Configuration ---
    let config: ConnectorConfig = match load_and_validate_config(&config_path) {
        Ok(c) => c,
        Err(e) => return Err(PyValueError::new_err(format!("Configuration Error: {:?}", e))),
    };

    println!("--- UncheckedIO: Schema Accepted ---");
    println!("Database: {}", config.connection_string);
    println!("Columns (in order): {:?}", config.schema.iter().map(|c| &c.column_name).collect::<Vec<_>>());

    // --- Phase 2: Run Core Logic ---
    let record_batch = py.allow_threads(|| {
        tokio::runtime::Builder::new_multi_thread()
            .enable_all()
            .build()
            .unwrap()
            .block_on(async {
                run_db_logic(config, blast_radius).await
            })
    }).map_err(|e| PyValueError::new_err(format!("Database/Runtime Error: {:?}", e)))?;

    // --- Phase 3: Return Data to Python ---
    let py_record_batch = PyRecordBatch::new(record_batch);
    py_record_batch.into_pyarrow(py)
}


// --- PYTHON MODULE EXPORT ---

#[pymodule]
fn unchecked_io(_py: Python<'_>, m: &Bound<'_, PyModule>) -> PyResult<()> {
    m.add_function(wrap_pyfunction!(load_data_from_config, m)?)?;
    Ok(())
}