/*
 * Configuration Module - Rust Web Server
 * 
 * Created by RSK World (https://rskworld.in)
 * Founder: Molla Samser
 * Designer & Tester: Rima Khatun
 * 
 * Contact:
 * - Email: hello@rskworld.in, support@rskworld.in
 * - Phone: +91 93305 39277
 * - Address: Nutanhat, Mongolkote, Purba Burdwan, West Bengal, India, 713147
 * 
 * © 2026 RSK World. All rights reserved.
 * Content used for educational purposes only.
 */

use serde::{Deserialize, Serialize};
use std::path::PathBuf;

/// Server configuration structure
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ServerConfig {
    pub host: String,
    pub port: u16,
    pub static_dir: PathBuf,
    pub workers: usize,
    pub max_connections: usize,
    pub request_timeout_secs: u64,
    pub buffer_size: usize,
}

impl Default for ServerConfig {
    fn default() -> Self {
        Self {
            host: "127.0.0.1".to_string(),
            port: 8080,
            static_dir: PathBuf::from("static"),
            workers: 4,
            max_connections: 1000,
            request_timeout_secs: 30,
            buffer_size: 8192,
        }
    }
}

impl ServerConfig {
    /// Create a new server configuration
    pub fn new(host: String, port: u16, static_dir: PathBuf, workers: usize) -> Self {
        Self {
            host,
            port,
            static_dir,
            workers,
            max_connections: 1000,
            request_timeout_secs: 30,
            buffer_size: 8192,
        }
    }

    /// Get the bind address for the server
    pub fn bind_address(&self) -> String {
        format!("{}:{}", self.host, self.port)
    }

    /// Get the server URL
    pub fn server_url(&self) -> String {
        format!("http://{}", self.bind_address())
    }

    /// Load configuration from file
    pub fn from_file<P: AsRef<std::path::Path>>(path: P) -> Result<Self, Box<dyn std::error::Error>> {
        let content = std::fs::read_to_string(path)?;
        let config: ServerConfig = toml::from_str(&content)?;
        Ok(config)
    }

    /// Save configuration to file
    pub fn to_file<P: AsRef<std::path::Path>>(&self, path: P) -> Result<(), Box<dyn std::error::Error>> {
        let content = toml::to_string_pretty(self)?;
        std::fs::write(path, content)?;
        Ok(())
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_default_config() {
        let config = ServerConfig::default();
        assert_eq!(config.host, "127.0.0.1");
        assert_eq!(config.port, 8080);
        assert_eq!(config.workers, 4);
    }

    #[test]
    fn test_bind_address() {
        let config = ServerConfig::new(
            "0.0.0.0".to_string(),
            3000,
            PathBuf::from("public"),
            8,
        );
        assert_eq!(config.bind_address(), "0.0.0.0:3000");
        assert_eq!(config.server_url(), "http://0.0.0.0:3000");
    }
}