use std::collections::BTreeMap;
use clap::{ArgMatches, SubCommand, App, Arg};
use openpgp_card::DecryptMe;
use rust_util::util_clap::{Command, CommandError};

pub struct CommandImpl;

impl Command for CommandImpl {
    fn name(&self) -> &str { "pgp-card-decrypt" }

    fn subcommand<'a>(&self) -> App<'a, 'a> {
        SubCommand::with_name(self.name()).about("OpenPGP Card Decrypt subcommand")
            .arg(Arg::with_name("pass").short("p").long("pass").takes_value(true).default_value("123456").help("OpenPGP card password"))
            .arg(Arg::with_name("cipher").short("c").long("cipher").takes_value(true).help("Cipher text HEX"))
            .arg(Arg::with_name("cipher-base64").short("b").long("cipher-base64").takes_value(true).help("Cipher text base64"))
            .arg(Arg::with_name("json").long("json").help("JSON output"))
    }

    fn run(&self, _arg_matches: &ArgMatches, sub_arg_matches: &ArgMatches) -> CommandError {
        let json_output = sub_arg_matches.is_present("json");
        if json_output {
            rust_util::util_msg::set_logger_std_out(false);
        }
        let pass_opt = sub_arg_matches.value_of("pass");
        let pass = opt_value_result!(pass_opt, "Pass must be assigned");
        if pass.len() < 6 { return simple_error!("Pass length:{}, must >= 6!", pass.len()); }
        let cipher = sub_arg_matches.value_of("cipher");
        let cipher_base64 = sub_arg_matches.value_of("cipher-base64");

        let cipher_bytes = if let Some(cipher) = cipher {
            opt_result!(hex::decode(cipher), "Decode cipher failed: {}")
        } else if let Some(cipher_base64) = cipher_base64 {
            opt_result!(base64::decode(cipher_base64), "Decode cipher-base64 failed: {}")
        } else {
            return simple_error!("cipher or cipher-base64 must assign one");
        };

        let user = crate::pgpcardutil::get_card_user_sw1_82(pass)?;
        let text = user.decrypt(DecryptMe::RSA(&cipher_bytes))?;
        success!("Clear text HEX: {}", hex::encode(&text));
        success!("Clear text base64: {}", base64::encode(&text));
        success!("Clear text UTF-8: {}", String::from_utf8_lossy(&text));

        if json_output {
            let mut json = BTreeMap::<&'_ str, String>::new();
            json.insert("cipher_hex", hex::encode(&cipher_bytes));
            json.insert("cipher_base64", base64::encode(&cipher_bytes));
            json.insert("text_hex", hex::encode(&text));
            json.insert("text_base64", base64::encode(&text));
            json.insert("text_utf8", String::from_utf8_lossy(&text).to_string());

            println!("{}", serde_json::to_string_pretty(&json).unwrap());
        }
        Ok(None)
    }
}