use clap::{Parser, Subcommand};

use std::fs;
use std::io;
use std::fmt;
use std::path::Path;

const STORAGE_PATH: &str = "storage";


#[derive(Parser)]
#[command(name = "mps", version = "0.0.1", about = "MyPasswordStorage: Tool for storing your passwords locally with synchronization with git.")]
struct Cli {
    #[command(subcommand)]
    command: Option<Commands>,
}

#[derive(Subcommand)]
enum Commands {
    
    /// Initialisation of storage and config, use this in first time of usage of mps
    Init,

    /// Adds new item with unique id to the db
    Add {
        #[arg(value_name="item_id")]
        input: String
    }
    
}

enum RuntimeError {
    Reinit,
    BadInit
}

impl fmt::Display for RuntimeError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match *self {
            RuntimeError::Reinit => write!(f, "Initialization can't be second time. Remove store folder if you want new inizilization"),
            RuntimeError::BadInit => write!(f, "Can`t create storage folder")
        }
    }
}

impl From<RuntimeError> for std::io::Error {
    fn from(err: RuntimeError) -> std::io::Error {
        match err {
            RuntimeError::Reinit => std::io::Error::new(std::io::ErrorKind::AlreadyExists, "Reinitialization attempted"),
            RuntimeError::BadInit => std::io::Error::new(std::io::ErrorKind::Other, "Bad initialization"),
        }
    }
}

fn init() -> Result<(), RuntimeError> {
    let path = Path::new(STORAGE_PATH);
    if path.exists() {
        return Err(RuntimeError::Reinit);
    }

    match fs::create_dir(STORAGE_PATH) {
        Ok(_) => return Ok(()),
        Err(_) => return Err(RuntimeError::BadInit),
    }

    Ok(())
}

fn main() -> io::Result<()> {
    let cli = Cli::parse();
    match &cli.command {
        Some(Commands::Init) => {
            init().map_err(|e| match e {
                RuntimeError::Reinit => std::io::Error::new(std::io::ErrorKind::AlreadyExists, "Reinitialization attempted"),
                RuntimeError::BadInit => std::io::Error::new(std::io::ErrorKind::Other, "Bad initialization"),
            })?;
            println!("Initializing storage and config.");
        }
        Some(Commands::Add{..}) => {
            println!("about to add new item");
        }
        None => {
            println!("Will be here init or list if storage inited");
        }
    }
    Ok(())
}