use serde::Deserialize;
use std::fs::File;

use crate::models::host::HostResult;

#[derive(Debug, Deserialize)]
pub struct ExportRequest {
    pub path: String,
    pub hosts: Vec<HostResult>,
}

#[tauri::command]
pub async fn export_csv(request: ExportRequest) -> Result<(), String> {
    let file = File::create(&request.path).map_err(|e| format!("Failed to create file: {}", e))?;

    let mut writer = csv::Writer::from_writer(file);

    // Header
    writer
        .write_record(["IP Address", "Status", "Latency (ms)", "Hostname"])
        .map_err(|e| format!("Failed to write header: {}", e))?;

    // Rows
    for host in &request.hosts {
        let ip = host.ip.to_string();
        let status = format!("{:?}", host.status);
        let rtt = match &host.ping {
            Some(p) => format!("{:.1}", p.rtt_ms),
            None => String::from("-"),
        };
        let hostname = host.hostname.clone().unwrap_or_default();

        writer
            .write_record([&ip, &status, &rtt, &hostname])
            .map_err(|e| format!("Failed to write row: {}", e))?;
    }

    writer
        .flush()
        .map_err(|e| format!("Failed to flush: {}", e))?;

    tracing::info!("Exported {} hosts to {}", request.hosts.len(), request.path);

    Ok(())
}