use anyhow::{anyhow, Context, Result};
use clap::Parser;
use codec::Encode;
use sp_core::{
    crypto::{AccountId32, DeriveJunction, Pair as _},
    sr25519::Pair,
};
use subxt::sp_runtime::MultiAddress;
use subxt::{ClientBuilder, DefaultConfig, DefaultExtra, PairSigner};

#[subxt::subxt(runtime_metadata_path = "res/metadata.scale")]
pub mod gdev_100 {}

pub type Api = gdev_100::RuntimeApi<DefaultConfig, DefaultExtra<DefaultConfig>>;
type Client = subxt::Client<DefaultConfig>;

#[derive(Parser, Debug)]
#[clap(author, version, about, long_about = None)]
struct Args {
    #[clap(subcommand)]
    pub subcommand: Subcommand,

    /// Secret key or BIP39 mnemonic
    /// (eventually followed by derivation path)
    #[clap(short, long)]
    secret: String,
    /// Websocket RPC endpoint
    #[clap(short, long, default_value = "ws://localhost:9945")]
    url: String,
}

#[derive(Debug, clap::Subcommand)]
pub enum Subcommand {
    /// Generate a revocation document for the provided account
    GenRevocDoc,
    #[clap(hide = true)]
    Repart {
        // Number of transactions per block to target
        target: u32,
        #[clap(short = 'o', long = "old-repart")]
        // Old/actual repartition
        actual_repart: Option<u32>,
    },
    #[clap(hide = true)]
    SpamRoll { actual_repart: usize },
}

#[tokio::main(flavor = "current_thread")]
async fn main() -> Result<()> {
    env_logger::init();

    let args = Args::parse();

    let pair = Pair::from_string(&args.secret, None)
        .map_err(|_| anyhow!("Invalid secret {}", args.secret))?;
    //let mut signer = PairSigner::new(pair.clone());

    let client: Client = ClientBuilder::new()
        .set_url(&args.url)
        .build()
        .await
        .with_context(|| "fail to connect to node")?;
    let api = client.clone().to_runtime_api::<Api>();

    let account_id: sp_core::crypto::AccountId32 = pair.public().into();
    let account = api.storage().system().account(account_id, None).await?;
    logs::info!("Account free balance: {}", account.data.free);

    match args.subcommand {
        Subcommand::GenRevocDoc => gen_revoc_doc(&api, &pair).await?,
        Subcommand::Repart {
            target,
            actual_repart,
        } => {
            let mut pairs = Vec::new();
            for i in actual_repart.unwrap_or_default()..target {
                let pair_i = pair
                    .derive(std::iter::once(DeriveJunction::hard::<u32>(i)), None)
                    .map_err(|_| anyhow!("Fail to derive //{}", i))?
                    .0;
                pairs.push((i, pair_i));
            }

            for (i, pair_i) in &pairs {
                /*let _ = api
                    .tx()
                    .balances()
                    .transfer(MultiAddress::Id(pair_i.public().into()), 501)
                    .sign_and_submit_then_watch(&signer)
                    .await?
                    .wait_for_in_block()
                    .await?;
                signer.increment_nonce();*/

                let pair_i_account = api
                    .storage()
                    .system()
                    .account(pair_i.public().into(), None)
                    .await?;
                logs::info!("account //{} balance: {}", i, pair_i_account.data.free);
            }
        }
        Subcommand::SpamRoll { actual_repart } => {
            let mut pairs = Vec::<(
                PairSigner<DefaultConfig, DefaultExtra<DefaultConfig>, Pair>,
                AccountId32,
            )>::with_capacity(actual_repart);
            for i in 0..actual_repart {
                let pair_i = pair
                    .derive(std::iter::once(DeriveJunction::hard::<u32>(i as u32)), None)
                    .map_err(|_| anyhow!("Fail to derive //{}", i))?
                    .0;
                let account_id_i = pair_i.public().into();
                pairs.push((PairSigner::new(pair_i), account_id_i));
            }

            loop {
                let mut watchers = Vec::with_capacity(actual_repart);
                for i in 0..(actual_repart - 1) {
                    let dest: AccountId32 = pairs[i + 1].1.clone();
                    let watcher = api
                        .tx()
                        .balances()
                        .transfer(MultiAddress::Id(dest), 1)
                        .sign_and_submit_then_watch(&pairs[i].0)
                        .await?;
                    pairs[i].0.increment_nonce();
                    logs::info!("send 1 cent from //{} to //{}", i, i + 1);
                    watchers.push(watcher);
                }
                let dest: AccountId32 = pairs[0].1.clone();
                let watcher = api
                    .tx()
                    .balances()
                    .transfer(MultiAddress::Id(dest), 1)
                    .sign_and_submit_then_watch(&pairs[actual_repart - 1].0)
                    .await?;
                pairs[actual_repart - 1].0.increment_nonce();
                logs::info!("send 1 cent from //{} to //0", actual_repart - 1);
                watchers.push(watcher);

                // Wait all transactions
                for watcher in watchers {
                    watcher.wait_for_in_block().await?;
                }
            }
        }
    }

    Ok(())
}

async fn gen_revoc_doc(api: &Api, pair: &Pair) -> Result<()> {
    let account_id: sp_core::crypto::AccountId32 = pair.public().into();
    let genesis_hash = api.storage().system().block_hash(0, None).await?;
    let payload = (account_id, genesis_hash).encode();
    let signature = pair.sign(&payload);

    println!("payload: 0x{}", hex::encode(payload));
    println!("signature: 0x{}", hex::encode(signature));

    Ok(())
}