You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: main.rs
    path of file: ./repos/neon/s3_scrubber/src
    
    the code of the file until where you have to start completion: use pageserver_api::shard::TenantShardId;
use s3_scrubber::garbage::{find_garbage, purge_garbage, PurgeMode};
use s3_scrubber::scan_metadata::scan_metadata;
use s3_scrubber::{init_logging, BucketConfig, ConsoleConfig, NodeKind, TraversingDepth};

use clap::{Parser, Subcommand};

#[derive(Parser)]
#[command(author, version, about, long_about = None)]
#[command(arg_required_else_help(true))]
struct Cli {
    #[command(subcommand)]
    command: Command,

    #[arg(short, long, default_value_t = false)]
    delete: bool,
}

#[derive(Subcommand, Debug)]
enum Command {
    FindGarbage {
        #[arg(short, long)]
        node_kind: NodeKind,
        #[arg(short, long, default_value_t=TraversingDepth::Tenant)]
        depth: TraversingDepth,
        #[arg(short, long, default_value_t = String::from("garbage.json"))]
        output_path: String,
    },
    PurgeGarbage {
        #[arg(short, long)]
        input_path: String,
        #[arg(short, long, default_value_t = PurgeMode::DeletedOnly)]
        mode: PurgeMode,
    },
    ScanMetadata {
        #[arg(short, long, default_value_t = false)]
        json: bool,
        #[arg(long = "tenant-id", num_args = 0..)]
        tenant_ids: Vec<TenantShardId>,
    },
}

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let cli = Cli::parse();

    let bucket_config = BucketConfig::from_env()?;

    let command_log_name = match &cli.command {
        Command::ScanMetadata { .. } => "scan",
        Command::FindGarbage { .. } => "find-garbage",
        Command::PurgeGarbage { .. } => "purge-garbage",
    };
    let _guard = init_logging(&format!(
        "{}_{}_{}_{}.log",
        std::env::args().next().unwrap(),
        command_log_name,
        bucket_config.bucket,
        chrono::Utc::now().format("%Y_%m_%d__%H_%M_%S")
    ));

    match cli.command {
        Command::ScanMetadata { json, tenant_ids } => {
            match scan_metadata(bucket_config.clone(), tenant_ids).await {
         
    
async fn main() -> anyhow::Result<()> {
    let cli = Cli::parse();

    let bucket_config = BucketConfig::from_env()?;

    let command_log_name = match &cli.command {
        Command::ScanMetadata { .. } => "scan",
        Command::FindGarbage { .. } => "find-garbage",
        Command::PurgeGarbage { .. } => "purge-garbage",
    };
    let _guard = init_logging(&format!(
        "{}_{}_{}_{}.log",
        std::env::args().next().unwrap(),
        command_log_name,
        bucket_config.bucket,
        chrono::Utc::now().format("%Y_%m_%d__%H_%M_%S")
    ));

    match cli.command {
        Command::ScanMetadata { json, tenant_ids } => {
            match scan_metadata(bucket_config.clone(), tenant_ids).await {
                Err(e) => {
                    tracing::error!("Failed: {e}");
                    Err(e)
                }
                Ok(summary) => {
                    if json {
                        println!("{}", serde_json::to_string(&summary).unwrap())
                    } else {
                        println!("{}", summary.summary_string());
                    }
                    if summary.is_fatal() {
                        Err(anyhow::anyhow!("Fatal scrub errors detected"))
                    } else if summary.is_empty() {
                        // Strictly speaking an empty bucket is a valid bucket, but if someone ran the
                        // scrubber they were likely expecting to scan something, and if we see no timelines
                        // at all then it's likely due to some configuration issues like a bad prefix
                        Err(anyhow::anyhow!(
                            "No timelines found in bucket {} prefix {}",
                            bucket_config.bucket,
                            bucket_config
                                .prefix_in_bucket
                                .unwrap_or("<none>".to_string())
                        ))
                    } else {
                        Ok(())
                    }
                }
            }
        }
        Command::FindGarbage {
            node_kind,
            depth,
            output_path,
        } => {
            let console_config = ConsoleConfig::from_env()?;
            find_garbage(bucket_config, console_config, depth, node_kind, output_path).await
        }
        Command::PurgeGarbage { input_path, mode } => {
            purge_garbage(input_path, mode, !cli.delete).await
        }
    }
}