#![warn(
    unused_extern_crates,
    missing_copy_implementations,
    rust_2018_idioms,
    clippy::cast_possible_truncation,
    clippy::cast_sign_loss,
    clippy::fallible_impl_from,
    clippy::cast_precision_loss,
    clippy::cast_possible_wrap,
    clippy::dbg_macro
)]
#![forbid(unsafe_code)]
#![allow(non_snake_case)]

use anyhow::{bail, Context, Result};
use prettytable::{row, Table};
use std::cmp::min;
use std::future::Future;
use std::path::PathBuf;
use std::sync::Arc;
use std::time::Duration;
use structopt::StructOpt;
use swap::bitcoin::{Amount, TxLock};
use swap::cli::command::{AliceMultiaddress, Arguments, Command, Data, MoneroParams};
use swap::database::Database;
use swap::env::{Config, GetConfig};
use swap::network::quote::BidQuote;
use swap::network::swarm;
use swap::protocol::bob;
use swap::protocol::bob::{Behaviour, Builder, EventLoop};
use swap::seed::Seed;
use swap::{bitcoin, env, monero};
use tracing::{debug, error, info, warn, Level};
use tracing_subscriber::FmtSubscriber;
use url::Url;
use uuid::Uuid;

#[macro_use]
extern crate prettytable;

#[tokio::main]
async fn main() -> Result<()> {
    let args = Arguments::from_args();

    let is_terminal = atty::is(atty::Stream::Stderr);
    let base_subscriber = |level| {
        FmtSubscriber::builder()
            .with_writer(std::io::stderr)
            .with_ansi(is_terminal)
            .with_target(false)
            .with_env_filter(format!("swap={}", level))
    };

    if args.debug {
        let subscriber = base_subscriber(Level::DEBUG)
            .with_timer(tracing_subscriber::fmt::time::ChronoLocal::with_format(
                "%F %T".to_owned(),
            ))
            .finish();

        tracing::subscriber::set_global_default(subscriber)?;
    } else {
        let subscriber = base_subscriber(Level::INFO)
            .without_time()
            .with_level(false)
            .finish();

        tracing::subscriber::set_global_default(subscriber)?;
    }

    let data: Data = args.data;
    let data_dir = data.0;

    let db =
        Database::open(data_dir.join("database").as_path()).context("Failed to open database")?;

    let seed =
        Seed::from_file_or_generate(data_dir.as_path()).context("Failed to read in seed file")?;

    let env_config = env::Testnet::get_config();

    match args.cmd {
        Command::BuyXmr {
            alice_peer_id,
            alice_multi_addr:
                AliceMultiaddress {
                    multiaddr: alice_addr,
                },
            monero_params:
                MoneroParams {
                    receive_monero_address,
                    monero_daemon_host,
                },
            electrum_rpc_url,
        } => {
            if receive_monero_address.network != env_config.monero_network {
                bail!(
                    "Given monero address is on network {:?}, expected address on network {:?}",
                    receive_monero_address.network,
                    env_config.monero_network
                )
            }

            let bitcoin_wallet =
                init_bitcoin_wallet(electrum_rpc_url, &seed, data_dir.clone(), env_config).await?;
            let (monero_wallet, _process) =
                init_monero_wallet(data_dir, monero_daemon_host, env_config).await?;
            let bitcoin_wallet = Arc::new(bitcoin_wallet);

            let mut swarm = swarm::new::<Behaviour>(&seed)?;
            swarm.add_address(alice_peer_id, alice_addr);

            let (event_loop, mut event_loop_handle) =
                EventLoop::new(swarm, alice_peer_id, bitcoin_wallet.clone())?;
            let event_loop = tokio::spawn(event_loop.run());

            let send_bitcoin = determine_btc_to_swap(
                event_loop_handle.request_quote(),
                bitcoin_wallet.balance(),
                bitcoin_wallet.new_address(),
                async {
                    while bitcoin_wallet.balance().await? == Amount::ZERO {
                        bitcoin_wallet.sync().await?;

                        tokio::time::sleep(Duration::from_secs(1)).await;
                    }

                    bitcoin_wallet.balance().await
                },
                bitcoin_wallet.max_giveable(TxLock::script_size()),
            )
            .await?;

            let swap_id = Uuid::new_v4();
            db.insert_peer_id(swap_id, alice_peer_id).await?;

            let swap = Builder::new(
                db,
                swap_id,
                bitcoin_wallet.clone(),
                Arc::new(monero_wallet),
                env_config,
                event_loop_handle,
                receive_monero_address,
            )
            .with_init_params(send_bitcoin)
            .build()?;

            tokio::select! {
                result = event_loop => {
                    result
                        .context("EventLoop panicked")?;
                },
                result = bob::run(swap) => {
                    result.context("Failed to complete swap")?;
                }
            }
        }
        Command::History => {
            let mut table = Table::new();

            table.add_row(row!["SWAP ID", "STATE"]);

            for (swap_id, state) in db.all_bob()? {
                table.add_row(row![swap_id, state]);
            }

            // Print the table to stdout
            table.printstd();
        }
        Command::Resume {
            swap_id,
            alice_multi_addr:
                AliceMultiaddress {
                    multiaddr: alice_addr,
                },
            monero_params:
                MoneroParams {
                    receive_monero_address,
                    monero_daemon_host,
                },
            electrum_rpc_url,
        } => {
            if receive_monero_address.network != env_config.monero_network {
                bail!("The given monero address is on network {:?}, expected address of network {:?}.", receive_monero_address.network, env_config.monero_network)
            }

            let bitcoin_wallet =
                init_bitcoin_wallet(electrum_rpc_url, &seed, data_dir.clone(), env_config).await?;
            let (monero_wallet, _process) =
                init_monero_wallet(data_dir, monero_daemon_host, env_config).await?;
            let bitcoin_wallet = Arc::new(bitcoin_wallet);

            let alice_peer_id = db.get_peer_id(swap_id)?;
            let mut swarm = swarm::new::<Behaviour>(&seed)?;
            swarm.add_address(alice_peer_id, alice_addr);

            let (event_loop, event_loop_handle) =
                EventLoop::new(swarm, alice_peer_id, bitcoin_wallet.clone())?;
            let handle = tokio::spawn(event_loop.run());

            let swap = Builder::new(
                db,
                swap_id,
                bitcoin_wallet.clone(),
                Arc::new(monero_wallet),
                env_config,
                event_loop_handle,
                receive_monero_address,
            )
            .build()?;

            tokio::select! {
                event_loop_result = handle => {
                    event_loop_result?;
                },
                swap_result = bob::run(swap) => {
                    swap_result?;
                }
            }
        }
        Command::Cancel {
            swap_id,
            force,
            electrum_rpc_url,
        } => {
            let bitcoin_wallet =
                init_bitcoin_wallet(electrum_rpc_url, &seed, data_dir, env_config).await?;

            let resume_state = db.get_state(swap_id)?.try_into_bob()?.into();
            let cancel =
                bob::cancel(swap_id, resume_state, Arc::new(bitcoin_wallet), db, force).await?;

            match cancel {
                Ok((txid, _)) => {
                    debug!("Cancel transaction successfully published with id {}", txid)
                }
                Err(bob::cancel::Error::CancelTimelockNotExpiredYet) => error!(
                    "The Cancel Transaction cannot be published yet, \
                        because the timelock has not expired. Please try again later."
                ),
                Err(bob::cancel::Error::CancelTxAlreadyPublished) => {
                    warn!("The Cancel Transaction has already been published.")
                }
            }
        }
        Command::Refund {
            swap_id,
            force,
            electrum_rpc_url,
        } => {
            let bitcoin_wallet =
                init_bitcoin_wallet(electrum_rpc_url, &seed, data_dir, env_config).await?;

            let resume_state = db.get_state(swap_id)?.try_into_bob()?.into();

            bob::refund(swap_id, resume_state, Arc::new(bitcoin_wallet), db, force).await??;
        }
    };
    Ok(())
}

async fn init_bitcoin_wallet(
    electrum_rpc_url: Url,
    seed: &Seed,
    data_dir: PathBuf,
    env_config: Config,
) -> Result<bitcoin::Wallet> {
    let wallet_dir = data_dir.join("wallet");

    let wallet = bitcoin::Wallet::new(
        electrum_rpc_url.clone(),
        &wallet_dir,
        seed.derive_extended_private_key(env_config.bitcoin_network)?,
        env_config,
    )
    .await
    .context("Failed to initialize Bitcoin wallet")?;

    wallet.sync().await?;

    Ok(wallet)
}

async fn init_monero_wallet(
    data_dir: PathBuf,
    monero_daemon_host: String,
    env_config: Config,
) -> Result<(monero::Wallet, monero::WalletRpcProcess)> {
    let network = env_config.monero_network;

    const MONERO_BLOCKCHAIN_MONITORING_WALLET_NAME: &str = "swap-tool-blockchain-monitoring-wallet";

    let monero_wallet_rpc = monero::WalletRpc::new(data_dir.join("monero")).await?;

    let monero_wallet_rpc_process = monero_wallet_rpc
        .run(network, monero_daemon_host.as_str())
        .await?;

    let monero_wallet = monero::Wallet::open_or_create(
        monero_wallet_rpc_process.endpoint(),
        MONERO_BLOCKCHAIN_MONITORING_WALLET_NAME.to_string(),
        env_config,
    )
    .await?;

    Ok((monero_wallet, monero_wallet_rpc_process))
}

async fn determine_btc_to_swap(
    request_quote: impl Future<Output = Result<BidQuote>>,
    initial_balance: impl Future<Output = Result<bitcoin::Amount>>,
    get_new_address: impl Future<Output = Result<bitcoin::Address>>,
    wait_for_deposit: impl Future<Output = Result<bitcoin::Amount>>,
    max_giveable: impl Future<Output = Result<bitcoin::Amount>>,
) -> Result<bitcoin::Amount> {
    debug!("Requesting quote");

    let bid_quote = request_quote.await?;

    info!("Received quote: 1 XMR ~ {}", bid_quote.price);

    // TODO: Also wait for more funds if balance < dust
    let initial_balance = initial_balance.await?;

    let balance = if initial_balance == Amount::ZERO {
        info!(
            "Please deposit the BTC you want to swap to {} (max {})",
            get_new_address.await?,
            bid_quote.max_quantity
        );

        let new_balance = wait_for_deposit
            .await
            .context("Failed to wait for Bitcoin deposit")?;

        info!("Received {}", new_balance);
        new_balance
    } else {
        info!("Found {} in wallet", initial_balance);
        initial_balance
    };

    let max_giveable = max_giveable
        .await
        .context("Failed to compute max 'giveable' Bitcoin amount")?;
    let fees = balance - max_giveable;

    let max_accepted = bid_quote.max_quantity;

    let btc_swap_amount = min(max_giveable, max_accepted);
    info!("Swapping {} with {} fees", btc_swap_amount, fees);

    Ok(btc_swap_amount)
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::determine_btc_to_swap;
    use ::bitcoin::Amount;
    use tracing::subscriber;

    #[tokio::test]
    async fn given_no_balance_and_transfers_less_than_max_swaps_max_giveable() {
        let _guard = subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());

        let amount = determine_btc_to_swap(
            async { Ok(quote_with_max(0.01)) },
            async { Ok(Amount::ZERO) },
            get_dummy_address(),
            async { Ok(Amount::from_btc(0.0001)?) },
            async { Ok(Amount::from_btc(0.00009)?) },
        )
        .await
        .unwrap();

        assert_eq!(amount, Amount::from_btc(0.00009).unwrap())
    }

    #[tokio::test]
    async fn given_no_balance_and_transfers_more_then_swaps_max_quantity_from_quote() {
        let _guard = subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());

        let amount = determine_btc_to_swap(
            async { Ok(quote_with_max(0.01)) },
            async { Ok(Amount::ZERO) },
            get_dummy_address(),
            async { Ok(Amount::from_btc(0.1)?) },
            async { Ok(Amount::from_btc(0.09)?) },
        )
        .await
        .unwrap();

        assert_eq!(amount, Amount::from_btc(0.01).unwrap())
    }

    #[tokio::test]
    async fn given_initial_balance_below_max_quantity_swaps_max_givable() {
        let _guard = subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());

        let amount = determine_btc_to_swap(
            async { Ok(quote_with_max(0.01)) },
            async { Ok(Amount::from_btc(0.005)?) },
            async { panic!("should not request new address when initial balance is > 0") },
            async { panic!("should not wait for deposit when initial balance > 0") },
            async { Ok(Amount::from_btc(0.0049)?) },
        )
        .await
        .unwrap();

        assert_eq!(amount, Amount::from_btc(0.0049).unwrap())
    }

    #[tokio::test]
    async fn given_initial_balance_above_max_quantity_swaps_max_quantity() {
        let _guard = subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());

        let amount = determine_btc_to_swap(
            async { Ok(quote_with_max(0.01)) },
            async { Ok(Amount::from_btc(0.1)?) },
            async { panic!("should not request new address when initial balance is > 0") },
            async { panic!("should not wait for deposit when initial balance > 0") },
            async { Ok(Amount::from_btc(0.09)?) },
        )
        .await
        .unwrap();

        assert_eq!(amount, Amount::from_btc(0.01).unwrap())
    }

    fn quote_with_max(btc: f64) -> BidQuote {
        BidQuote {
            price: Amount::from_btc(0.001).unwrap(),
            max_quantity: Amount::from_btc(btc).unwrap(),
        }
    }

    async fn get_dummy_address() -> Result<bitcoin::Address> {
        Ok("1PdfytjS7C8wwd9Lq5o4x9aXA2YRqaCpH6".parse()?)
    }
}