use crate::cfg::config::Config;
use std::{io, 
          fs::{self, File, create_dir_all},
          str, 
          path::Path}; 
          
// use emissary_core::i2np::tunnel::build;
use flate2::read::GzDecoder;
use serde::{Deserialize, Serialize};
use tar::Archive;
use toml; 

#[derive(Serialize, Debug, Deserialize)]
pub enum archs {
    X86_64,
    Aarch64,
    X86,
}

#[derive(Serialize, Debug, Deserialize)]
pub struct Package {
    name: String, 
    version: String, 
    arch: archs, 
    descr: Option<String>,
}

#[derive(Deserialize, Debug)]
struct Install {
    package: Package,
    path: String, 
    user: String, 
    group: String, 
    mode: String,
    //. Cancels the previous fields and installs them using the shell script
    custom_script: Option<String>,
}

#[derive(Deserialize, Debug)]
struct Setts {
    env: Option<String>, // Export environment variables if this needed 
    test: Option<String>, // Test the package after installation
}

#[derive(Deserialize, Serialize, Debug)]
pub enum BuildSystems {
    Make,
    CMake,
    Meson, 
    Cargo
}

#[derive(Deserialize, Debug)]
struct Build {
    build_system: BuildSystems, 
    env: Option<String>,
    script: Option<String>,
}

impl Package { 
    /// Load meta information from the .mesk archive.
    ///
    /// This function parses the meta information from the .mesk archive,
    /// which includes the package name, version, architecture, description,
    /// installation path, user, group, mode, and custom installation script 
    /// and deserializing this information. Returns (Install, Option<Setts>, Option<Build>)
    /// 
    /// The function expects the 'INSTALL', 'SETTS', and 'BUILD' files to be present
    /// in the `config.paths.cache_dir`. It specifically requires the 'INSTALL' file.
    /// 
    /// # Errors
    ///
    /// Returns an error if the `cache_dir` cannot be created, if the required 'INSTALL' file
    /// is not found, or if the 'INSTALL' file is empty.
    fn loadmeta(minimal_package_meta: Package) -> Result<(Install, Option<Setts>, Option<Build>), Box<dyn std::error::Error>> { // Changed return type for more flexibility
        /* 
                Example INSTALL format: 
                [package]
                name = "my-package"
                version = "1.0.0"
                arch = "X86_64"
                descr = "Just example INSTALL script"

                [install]
                path = "/usr/bin/my-package"
                user = "root"
                group = "root"
                mode = "755"

                # Also [install] can be 
                # path = "/usr/bin/my-package"
                # user = "root"
                # group = "root"
                # mode = "755"
                # custom_script = "./install.sh" OR 
                # custom_script = """
                #     echo "Installing my-package"
                #     sudo apt-get install my-package
                # """
        */


        let config = Config::parse()?; // Propagate error if parsing fails

        // Ensure the cache directory exists
        fs::create_dir_all(&config.paths.cache_dir)?;


        let cache_dir = &config.paths.cache_dir;
        let install_path = Path::new(cache_dir).join(format!("{}/INSTALL", minimal_package_meta.name));
        let setts_path = Path::new(cache_dir).join(format!("{}/SETTS", minimal_package_meta.name));
        let build_path = Path::new(cache_dir).join(format!("{}/BUILD", minimal_package_meta.name));

        // Check for required 'INSTALL' file
        if !install_path.exists() {
            return Err(io::Error::new(
                io::ErrorKind::NotFound,
                "File INSTALL not found in cache directory"
            ).into()); // Convert to Box<dyn Error>
        }

        // Read and deserialize the INSTALL file
        let install_content = fs::read_to_string(&install_path)?;
        let install_meta: Install = toml::from_str(&install_content)?;

        // Initialize optional structures as None
        let mut setts_meta: Option<Setts> = None;
        let mut build_meta: Option<Build> = None;

        // Attempt to read and deserialize the SETTS file if it exists
        if setts_path.exists() {
            let setts_content = fs::read_to_string(&setts_path)?;
            setts_meta = Some(toml::from_str(&setts_content)?);
        }

        // Attempt to read and deserialize the BUILD file if it exists
        if build_path.exists() {
            let build_content = fs::read_to_string(&build_path)?;
            build_meta = Some(toml::from_str(&build_content)?);
        }

        // Log if custom script is present
        if let Some(ref script) = install_meta.custom_script {
            println!("Custom script found for package: {}", install_meta.package.name);
            // Consider logging the script content or just its presence based on verbosity
            // e.g., log::debug!("Custom script content: {}", script);
        } else {
            println!("No custom script for package: {}", install_meta.package.name);
        }

        Ok((install_meta, setts_meta, build_meta))
    }
    
    

    /// Checks if the archive contains INSTALL, SETTS and BUILD files.
    ///
    /// Checks if INSTALL file exists and is not empty. If it does not exist or is empty, returns an error.
    ///
    /// Checks if SETTS and BUILD files exist and are not empty. If they do not exist or are empty, logs a warning.
    /// # Errors 
    /// * Returns an error if INSTALL file does not exist or is empty.
    /// * Returns an error if INSTALL file is empty.
    ///
    // TODO: Add meta-files validation here. 
    pub fn check(path_to_archive: String) -> Result<bool, std::io::Error> {
        let config: Config = Config::parse().unwrap(); 

        create_dir_all(&config.paths.cache_dir)?;

        let file = File::open(&path_to_archive)?;
        let gz = GzDecoder::new(file);
        let mut archive = Archive::new(gz);

        archive.unpack(&config.paths.cache_dir)?;

        let install_path = Path::new(&config.paths.cache_dir).join("INSTALL");
        let setts_path = Path::new(&config.paths.cache_dir).join("SETTS");
        let build_path = Path::new(&config.paths.cache_dir).join("BUILD");

        if !install_path.exists() {
            return Err(std::io::Error::new(
                std::io::ErrorKind::NotFound,
                "INSTALL file not found in archive",
            ));
        }

        let install_content = std::fs::read_to_string(&install_path)?;
        if install_content.trim().is_empty() {
            return Err(std::io::Error::new(
                std::io::ErrorKind::InvalidData,
                "INSTALL file is empty",
            ));
        }

        if !setts_path.exists() {
            log::warn!("SETTS file not found in archive. Make sure you dont need this.");
        } else {
            let setts_content = std::fs::read_to_string(&setts_path)?;
            if setts_content.trim().is_empty() {
                log::warn!("SETTS file is empty. Make sure you dont need this.");
            }
        }

        if !build_path.exists() {
            log::warn!("BUILD file not found in archive. Make sure you dont need this.");
        } else {
            let build_content = std::fs::read_to_string(&build_path)?;
            if build_content.trim().is_empty() {
                log::warn!("BUILD file is empty. Make sure you dont need this.");
            }
        }

        Ok(true)
    }

    pub fn build() -> Result<bool, std::io::Error> {
        todo!();  
    }
    pub fn install() -> Result<bool, std::io::Error> {
        todo!(); 
    } 
    pub fn gen_index() -> Result<bool, std::io::Error> {    
        todo!();

    }
}