use std::path::PathBuf;

use clap::Parser;

#[derive(Debug, Clone, Parser)]
#[command(name = "meterbox", about = "Host resource usage dashboard")]
pub struct Config {
    /// Bind address — default localhost only (safe behind Caddy/Rathole)
    #[arg(long, env = "METERBOX_LISTEN", default_value = "127.0.0.1:8787")]
    pub listen: String,

    /// SQLite database path
    #[arg(long, env = "METERBOX_DB", default_value = "data/meterbox.db")]
    pub db_path: PathBuf,

    /// Directory with built React assets
    #[arg(long, env = "METERBOX_STATIC", default_value = "frontend/dist")]
    pub static_dir: PathBuf,

    /// Sample interval in seconds
    #[arg(long, env = "METERBOX_INTERVAL_SECS", default_value_t = 30)]
    pub interval_secs: u64,

    /// Retain samples for this many days (max ~3 months)
    #[arg(long, env = "METERBOX_RETENTION_DAYS", default_value_t = 90)]
    pub retention_days: i64,

    /// Hard cap for SQLite on-disk size (main + WAL + SHM), bytes. Default 10 GiB.
    #[arg(long, env = "METERBOX_MAX_DB_BYTES", default_value_t = 10 * 1024 * 1024 * 1024)]
    pub max_db_bytes: u64,

    /// How often the cleanup job runs (seconds). Default 1 hour.
    #[arg(long, env = "METERBOX_CLEANUP_INTERVAL_SECS", default_value_t = 3600)]
    pub cleanup_interval_secs: u64,
}

impl Config {
    pub fn ensure_dirs(&self) -> anyhow::Result<()> {
        if let Some(parent) = self.db_path.parent() {
            if !parent.as_os_str().is_empty() {
                std::fs::create_dir_all(parent)?;
            }
        }
        Ok(())
    }
}