use clap::{Parser, Subcommand};

use std::fs;
use std::io::{self, Write};
use std::path::Path;


const STORAGE_FOLDER: &str = "storage";
const STORAGE_PATH: &str = "storage/db.mps"; // TODO: concat from STORAGE_FOLDER


#[derive(Parser)]
#[command(name = "mps", version = "0.0.1", about = "MyPasswordStorage: Tool for storing your passwords locally with git synchronization")]
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
    }
    
}

fn is_inited() -> bool {
    let path = Path::new(STORAGE_FOLDER);
    return path.exists();
}

fn init() -> io::Result<()> {
    if is_inited() {
        return Err(io::Error::new(io::ErrorKind::AlreadyExists, "Reinitialization attempted"));
    }
    match fs::create_dir(STORAGE_FOLDER) {
        Ok(_) => {
            println!("Create folder for storage"); // TODO: make it only in debug mode
        },
        Err(_) => return Err(io::Error::new(io::ErrorKind::Other, "Can`t create storage folder")),
    }

    match fs::File::create(STORAGE_PATH) {
        Ok(_) => {
            println!("Storage db created");
        },
        Err(_) => {
            return Err(io::Error::new(io::ErrorKind::Other, "Can`t create mps.db")); // TODO: better error, not just Other
        }
    }
    
    Ok(())
}

fn add() -> io::Result<()> {
    let mut file = match fs::OpenOptions::new()
        .write(true)
        .open(STORAGE_PATH)
        {
            Ok(file) => file,
            Err(_) => {
                return Err(io::Error::new(io::ErrorKind::Other, "can`t open database")); // TODO: better error handling
            }
        };

    writeln!(file, "new item")?;
    Ok(())
}

fn main() -> io::Result<()> {
    let cli = Cli::parse();
    match &cli.command {
        Some(Commands::Init) => {
            init()?;
            println!("Initialization complete");
        }
        Some(Commands::Add{..}) => {
            add()?;
        }
        None => {
            if !is_inited() {
                println!("Do you want to init your storage? [Y/n]");
                let mut input = String::new();
                io::stdin()
                    .read_line(&mut input)
                    .expect("Failed to read answer");
                let input = input.trim().to_lowercase();
                match input.as_str() {
                    "y" => init()?,
                    "n" => println!("You chose No."),
                    _ => init()?,
                }
            } else {
                println!("login, not implemented yet")
            }
        }
    }
    Ok(())
}