use super::setup;
use eyre::Result;
use reth_db::{tables, DatabaseEnv};
use reth_db_api::{database::Database, table::TableImporter};
use reth_db_common::DbTool;
use reth_node_core::dirs::{ChainPath, DataDirPath};
use reth_primitives::BlockNumber;
use reth_provider::{providers::StaticFileProvider, ProviderFactory};
use reth_stages::{stages::AccountHashingStage, Stage, StageCheckpoint, UnwindInput};
use tracing::info;

pub(crate) async fn dump_hashing_account_stage<DB: Database>(
    db_tool: &DbTool<DB>,
    from: BlockNumber,
    to: BlockNumber,
    output_datadir: ChainPath<DataDirPath>,
    should_run: bool,
) -> Result<()> {
    let (output_db, tip_block_number) = setup(from, to, &output_datadir.db(), db_tool)?;

    // Import relevant AccountChangeSets
    output_db.update(|tx| {
        tx.import_table_with_range::<tables::AccountChangeSets, _>(
            &db_tool.provider_factory.db_ref().tx()?,
            Some(from),
            to,
        )
    })??;

    unwind_and_copy(db_tool, from, tip_block_number, &output_db)?;

    if should_run {
        dry_run(
            ProviderFactory::new(
                output_db,
                db_tool.chain(),
                StaticFileProvider::read_write(output_datadir.static_files())?,
            ),
            to,
            from,
        )?;
    }

    Ok(())
}

/// Dry-run an unwind to FROM block and copy the necessary table data to the new database.
fn unwind_and_copy<DB: Database>(
    db_tool: &DbTool<DB>,
    from: u64,
    tip_block_number: u64,
    output_db: &DatabaseEnv,
) -> eyre::Result<()> {
    let provider = db_tool.provider_factory.provider_rw()?;
    let mut exec_stage = AccountHashingStage::default();

    exec_stage.unwind(
        &provider,
        UnwindInput {
            unwind_to: from,
            checkpoint: StageCheckpoint::new(tip_block_number),
            bad_block: None,
        },
    )?;
    let unwind_inner_tx = provider.into_tx();

    output_db.update(|tx| tx.import_table::<tables::PlainAccountState, _>(&unwind_inner_tx))??;

    Ok(())
}

/// Try to re-execute the stage straight away
fn dry_run<DB: Database>(
    output_provider_factory: ProviderFactory<DB>,
    to: u64,
    from: u64,
) -> eyre::Result<()> {
    info!(target: "reth::cli", "Executing stage.");

    let provider = output_provider_factory.provider_rw()?;
    let mut stage = AccountHashingStage {
        clean_threshold: 1, // Forces hashing from scratch
        ..Default::default()
    };

    loop {
        let input = reth_stages::ExecInput {
            target: Some(to),
            checkpoint: Some(StageCheckpoint::new(from)),
        };
        if stage.execute(&provider, input)?.done {
            break
        }
    }

    info!(target: "reth::cli", "Success.");

    Ok(())
}