use base64::engine::general_purpose::STANDARD;
use base64::Engine;
use clap::{App, Arg, ArgMatches, SubCommand};

use jwt::{AlgorithmType, Header, ToBase64};
use rust_util::util_clap::{Command, CommandError};
use rust_util::{util_msg, XResult};
use serde_json::{Map, Value};
use std::collections::BTreeMap;

use crate::cmd_sign_jwt::{build_jwt_parts, merge_header_claims, merge_payload_claims};
use crate::ecdsautil::parse_ecdsa_to_rs;
use crate::keyutil::{parse_key_uri, KeyUri};
use crate::{hmacutil, util};

const SEPARATOR: &str = ".";

pub struct CommandImpl;

impl Command for CommandImpl {
    fn name(&self) -> &str {
        "sign-jwt-se"
    }

    fn subcommand<'a>(&self) -> App<'a, 'a> {
        SubCommand::with_name(self.name()).about("Sign JWT subcommand")
            .arg(Arg::with_name("key").long("key").required(true).takes_value(true).help("Key uri"))
            .arg(Arg::with_name("key-id").short("K").long("key-id").takes_value(true).help("Header key ID"))
            .arg(Arg::with_name("claims").short("C").long("claims").takes_value(true).multiple(true).help("Claims, key:value"))
            .arg(Arg::with_name("payload").short("P").long("payload").takes_value(true).help("Claims in JSON"))
            .arg(Arg::with_name("jti").long("jti").help("Claims jti"))
            .arg(Arg::with_name("validity").long("validity").takes_value(true).help("Claims validity period e.g. 10m means 10 minutes (s - second, m - minute, h - hour, d - day)"))
            .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 {
            util_msg::set_logger_std_out(false);
        }

        let mut json = BTreeMap::<&'_ str, String>::new();

        let private_key = opt_value_result!(
            sub_arg_matches.value_of("key"),
            "Private key PKCS#8 DER base64 encoded or PEM"
        );
        let private_key = hmacutil::try_hmac_decrypt_to_string(private_key)?;
        let KeyUri::SecureEnclaveKey(se_key_uri) = parse_key_uri(&private_key)?;
        debugging!("Secure enclave key URI: {:?}", se_key_uri);

        let (header, payload, jwt_claims) = build_jwt_parts(sub_arg_matches)?;

        let token_string = sign_jwt(&se_key_uri.private_key, header, &payload, &jwt_claims)?;

        debugging!("Singed JWT: {}", token_string);
        if json_output {
            json.insert("token", token_string.clone());
        } else {
            success!("Singed JWT: {}", token_string);
        }

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

fn sign_jwt(
    private_key: &str,
    mut header: Header,
    payload: &Option<String>,
    claims: &Map<String, Value>,
) -> XResult<String> {
    header.algorithm = AlgorithmType::Es256;
    debugging!("Header: {:?}", header);
    debugging!("Claims: {:?}", claims);

    let header = opt_result!(header.to_base64(), "Header to base64 failed: {}");
    let claims = merge_payload_claims(payload, claims)?;
    let tobe_signed = merge_header_claims(header.as_bytes(), claims.as_bytes());

    let private_key_representation = STANDARD.decode(private_key)?;
    let signed_data_der =
        swift_secure_enclave_tool_rs::private_key_sign(&private_key_representation, &tobe_signed)?;

    let signed_data = parse_ecdsa_to_rs(signed_data_der.as_slice())?;

    let signature = util::base64_encode_url_safe_no_pad(&signed_data);

    Ok([&*header, &*claims, &signature].join(SEPARATOR))
}