use anyhow::Context;
use decaf377_rdsa::{Signature, SpendAuth};
use futures::{FutureExt, TryStreamExt};
use penumbra_fee::GasPrices;
use penumbra_governance::ValidatorVoteBody;
use penumbra_proto::{
    custody::v1::{AuthorizeValidatorDefinitionRequest, AuthorizeValidatorVoteRequest},
    util::tendermint_proxy::v1::tendermint_proxy_service_client::TendermintProxyServiceClient,
    view::v1::broadcast_transaction_response::Status as BroadcastStatus,
    view::v1::GasPricesRequest,
    DomainType,
};
use penumbra_stake::validator::Validator;
use penumbra_transaction::{gas::GasCost, txhash::TransactionId, Transaction, TransactionPlan};
use penumbra_view::ViewClient;
use std::future::Future;
use tonic::transport::{Channel, ClientTlsConfig};
use tracing::instrument;

use crate::App;

impl App {
    pub async fn build_and_submit_transaction(
        &mut self,
        plan: TransactionPlan,
    ) -> anyhow::Result<TransactionId> {
        let gas_prices: GasPrices = self
            .view
            .as_mut()
            .context("view service must be initialized")?
            .gas_prices(GasPricesRequest {})
            .await?
            .into_inner()
            .gas_prices
            .expect("gas prices must be available")
            .try_into()?;
        let transaction = self.build_transaction(plan).await?;
        let gas_cost = transaction.gas_cost();
        let fee = gas_prices.fee(&gas_cost);
        assert!(
            transaction.transaction_parameters().fee.amount() >= fee,
            "paid fee {} must be greater than minimum fee {}",
            transaction.transaction_parameters().fee.amount(),
            fee
        );
        self.submit_transaction(transaction).await
    }

    pub fn build_transaction(
        &mut self,
        plan: TransactionPlan,
    ) -> impl Future<Output = anyhow::Result<Transaction>> + '_ {
        println!(
            "building transaction [{} actions, {} proofs]...",
            plan.actions.len(),
            plan.num_proofs(),
        );
        let start = std::time::Instant::now();
        let tx = penumbra_wallet::build_transaction(
            &self.config.full_viewing_key,
            self.view.as_mut().expect("view service initialized"),
            &mut self.custody,
            plan,
        );
        async move {
            let tx = tx.await?;
            let elapsed = start.elapsed();
            println!(
                "finished proving in {}.{:03} seconds [{} actions, {} proofs, {} bytes]",
                elapsed.as_secs(),
                elapsed.subsec_millis(),
                tx.actions().count(),
                tx.num_proofs(),
                tx.encode_to_vec().len()
            );
            Ok(tx)
        }
    }

    pub async fn sign_validator_definition(
        &mut self,
        validator_definition: Validator,
    ) -> anyhow::Result<Signature<SpendAuth>> {
        let request = AuthorizeValidatorDefinitionRequest {
            validator_definition: Some(validator_definition.into()),
            pre_authorizations: vec![],
        };
        self.custody
            .authorize_validator_definition(request)
            .await?
            .into_inner()
            .validator_definition_auth
            .ok_or_else(|| anyhow::anyhow!("missing validator definition auth"))?
            .try_into()
    }

    pub async fn sign_validator_vote(
        &mut self,
        validator_vote: ValidatorVoteBody,
    ) -> anyhow::Result<Signature<SpendAuth>> {
        let request = AuthorizeValidatorVoteRequest {
            validator_vote: Some(validator_vote.into()),
            pre_authorizations: vec![],
        };
        // Use the separate governance custody service, if one is configured, to sign the validator
        // vote. This allows the governance custody service to have a different key than the main
        // custody, which is useful for validators who want to have a separate key for voting.
        self.governance_custody // VERY IMPORTANT: use governance custody here!
            .authorize_validator_vote(request)
            .await?
            .into_inner()
            .validator_vote_auth
            .ok_or_else(|| anyhow::anyhow!("missing validator vote auth"))?
            .try_into()
    }

    /// Submits a transaction to the network.
    pub async fn submit_transaction(
        &mut self,
        transaction: Transaction,
    ) -> anyhow::Result<TransactionId> {
        println!("broadcasting transaction and awaiting confirmation...");
        let mut rsp = self.view().broadcast_transaction(transaction, true).await?;

        let id = (async move {
            while let Some(rsp) = rsp.try_next().await? {
                match rsp.status {
                    Some(status) => match status {
                        BroadcastStatus::BroadcastSuccess(bs) => {
                            println!(
                                "transaction broadcast successfully: {}",
                                TransactionId::try_from(
                                    bs.id.expect("detected transaction missing id")
                                )?
                            );
                        }
                        BroadcastStatus::Confirmed(c) => {
                            let id = c.id.expect("detected transaction missing id").try_into()?;
                            if c.detection_height != 0 {
                                println!(
                                    "transaction confirmed and detected: {} @ height {}",
                                    id, c.detection_height
                                );
                            } else {
                                println!("transaction confirmed and detected: {}", id);
                            }
                            return Ok(id);
                        }
                    },
                    None => {
                        // No status is unexpected behavior
                        return Err(anyhow::anyhow!(
                            "empty BroadcastTransactionResponse message"
                        ));
                    }
                }
            }

            Err(anyhow::anyhow!(
                "should have received BroadcastTransaction status or error"
            ))
        }
        .boxed())
        .await
        .context("error broadcasting transaction")?;

        Ok(id)
    }

    /// Submits a transaction to the network, returning `Ok` as soon as the
    /// transaction has been submitted, rather than waiting for confirmation.
    #[instrument(skip(self, transaction))]
    pub async fn submit_transaction_unconfirmed(
        &mut self,
        transaction: Transaction,
    ) -> anyhow::Result<()> {
        println!("broadcasting transaction without confirmation...");
        self.view()
            .broadcast_transaction(transaction, false)
            .await?;

        Ok(())
    }

    // TODO: why do we need this here but not in the view crate?
    pub async fn pd_channel(&self) -> anyhow::Result<Channel> {
        match self.config.grpc_url.scheme() {
            "http" => Ok(Channel::from_shared(self.config.grpc_url.to_string())?
                .connect()
                .await?),
            "https" => Ok(Channel::from_shared(self.config.grpc_url.to_string())?
                .tls_config(ClientTlsConfig::new())?
                .connect()
                .await?),
            other => Err(anyhow::anyhow!("unknown url scheme {other}"))
                .with_context(|| format!("could not connect to {}", self.config.grpc_url)),
        }
    }

    pub async fn tendermint_proxy_client(
        &self,
    ) -> anyhow::Result<TendermintProxyServiceClient<Channel>> {
        let channel = self.pd_channel().await?;
        Ok(TendermintProxyServiceClient::new(channel))
    }
}