mod db;


use db::{DB, Item};

use once_cell::sync::Lazy;

use clap::{Parser, Subcommand};

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


static STORAGE_FOLDER: &str = "storage";
static STORAGE_PATH: Lazy<String> = Lazy::new(|| { 
    format!("{}/db.mps", 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")]
        id: String
    },
    
    /// Lists all ids stored in db
    List
    
}


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"));
    }
    fs::create_dir(STORAGE_FOLDER)?;
    println!("Storage folder created");

    fs::File::create(&*STORAGE_PATH)?;
    println!("Storage db created.");
    println!("Initialization complete.");
    println!("");
    println!("Now it's required to add folder `{}` under git manually.", STORAGE_FOLDER);
    println!("Don't worry it's going to be encrypted.");
    Ok(())
}

fn add(id: &String) -> io::Result<()> {
    let mut db = DB::new(&*STORAGE_PATH)?;
    if db.contains(id) {
        // TODO: ask to edit existing in outer function which invoked this one
        return Err(io::Error::new(
            io::ErrorKind::InvalidInput,
            format!("Dublicate item id: {}. Item id's must be unique.", id)
        ))
    }

    db.items.insert(Item::from(id.clone()));
    db.dump()?;
    
    Ok(())
}

fn list() -> io:: Result<()> {
    let db = DB::new(&STORAGE_PATH)?;
    let mut vec: Vec<_> = db.items.iter().collect();
    vec.sort();
    for item in &vec {
        println!("{}", item);
    }
    Ok(())
}

enum PROMPT {
    YES,
    NO
}

fn get_prompt(question: &str) -> io::Result<PROMPT> {
    print!("{} [Y/n] ", question);
    io::stdout().flush()?;
    let mut input = String::new();
    io::stdin().read_line(&mut input)?;
    let input = input.trim().to_lowercase();
    match input.as_str() {
        "y" => Ok(PROMPT::YES),
        "n" => Ok(PROMPT::NO),
        _ => Ok(PROMPT::YES),
    }

}

fn main() -> io::Result<()> {
    let cli = Cli::parse();
    match &cli.command {
        Some(Commands::Init) => {
            init()?;
        }
        Some(Commands::Add{ id }) => {
            add(id)?;
        }
        Some(Commands::List) => {
            list()?;
        }
        None => {
            if !is_inited() {
                match get_prompt("Do you want to init your storage?")? {
                    PROMPT::YES => init()?,
                    PROMPT::NO => {
                        println!("mps can work only when storage inited.");
                        println!("Hint: you cant do");
                        println!("  git clone <your_storage_git_url> {}", STORAGE_FOLDER);
                        println!("to init manually your storage and config")
                    },                   
                }    
            } else {
                println!("login, not implemented yet")
            }
        }
    }
    Ok(())
}