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/objc2/crates/header-translator/src
    
    the code of the file until where you have to start completion: use std::fs;
use std::io::{Read, Write};
use std::path::{Path, PathBuf};

use apple_sdk::{AppleSdk, DeveloperDirectory, Platform, SdkPath, SimpleSdk};
use clang::{Clang, EntityKind, EntityVisitResult, Index, TranslationUnit};
use tracing::{debug_span, error, info, info_span, trace, trace_span};
use tracing_subscriber::filter::LevelFilter;
use tracing_subscriber::layer::{Layer, SubscriberExt};
use tracing_subscriber::registry::Registry;
use tracing_subscriber::util::SubscriberInitExt;
use tracing_tree::HierarchicalLayer;

use header_translator::{global_analysis, run_cargo_fmt, Config, Context, File, Output, Stmt};

type BoxError = Box<dyn std::error::Error + Send + Sync + 'static>;

fn main() -> Result<(), BoxError> {
    // use tracing_subscriber::fmt;
    Registry::default()
        // .with(
        //     fmt::Layer::default()
        //         .compact()
        //         .without_time()
        //         .with_target(false)
        //         .with_span_events(fmt::format::FmtSpan::ACTIVE)
        //         .with_filter(LevelFilter::INFO)
        //         .with_filter(tracing_subscriber::filter::filter_fn(|metadata| {
        //             metadata.is_span() && metadata.level() == &tracing::Level::INFO
        //         })),
        // )
        // .with(tracing_subscriber::fmt::Layer::default().with_filter(LevelFilter::ERROR))
        .with(
            HierarchicalLayer::new(2)
                .with_targets(false)
                .with_indent_lines(true)
                // Note: Change this to DEBUG if you want to see more info
                .with_filter(LevelFilter::INFO),
        )
        .init();
    let _span = info_span!("running").entered();

    let manifest_dir = Path::new(env!("CARGO_MANIFEST_DIR"));
    let workspace_dir = manifest_dir.parent().unwrap();
    let crate_src = workspace_dir.join("icrate/src");

    let config = load_config(manifest_dir);

    clang_sys::load()?;
    info!(clang_version = clang::get_version());

    let clang = Clang::new()?;
    let index = Index::new(&clang, true, true);

    let developer_dir = if let Some(path) = std::env::args_os().nth(1) {
        DeveloperDirectory::from(PathBuf::from(path))
    } else {
        DeveloperDirectory::from_xcode_select()?
    };

    let sdks: Vec<_> = developer_dir
        .platforms()
        .expect("developer dir platforms")
        .into_iter()
        .map(|platform| {
            let sdks: Vec<_> = platform
                .find_sdks::<SimpleSdk>()
                .expect("platform sdks")
                .into_iter()
                .filter(|sdk| !sdk.is_symlink() && sdk.platform() == &*platform)
                .collect();
            if sdks.len() != 1 {
                panic!("found multiple sdks {sdks:?} in {:?}", &*platform);
            }
            sdks[0].sdk_path()
        })
        .collect();

    if sdks.len() != 10 {
        error!("should have one of each platform: {sdks:?}");
    }

    let mut final_result = None;

    // TODO: Compare between SDKs
    for sdk in sdks {
        // These are found using the `get_llvm_targets.fish` helper script
        let llvm_targets: &[_] = match &sdk.platform {
            Platform::MacOsX => &[
                "x86_64-apple-macosx10.12.0",
                // "arm64-apple-macosx11.0.0",
                // "i686-apple-macosx10.12.0",
            ],
            Platform::IPhoneOs => &[
                // "arm64-apple-ios10.0.0",
                // "armv7s-apple-ios10.0.0",
                // "arm64-apple-ios14.0-macabi",
                // "x86_64-apple-ios13.0-macabi",
            ],
            // Platform::IPhoneSimulator => &[
            //     "arm64-apple-ios10.0.0-simulator",
            //     "x86_64-apple-ios10.0.0-simulator",
            //     "i386-apple-ios10.0.0-simulator",
            // ],
            // Platform::AppleTvOs => &["arm64-apple-tvos", "x86_64-apple-tvos"],
            // Platform::WatchOs => &["arm64_32-apple-watchos", "armv7k-ap
    
fn main() -> Result<(), BoxError> {
    // use tracing_subscriber::fmt;
    Registry::default()
        // .with(
        //     fmt::Layer::default()
        //         .compact()
        //         .without_time()
        //         .with_target(false)
        //         .with_span_events(fmt::format::FmtSpan::ACTIVE)
        //         .with_filter(LevelFilter::INFO)
        //         .with_filter(tracing_subscriber::filter::filter_fn(|metadata| {
        //             metadata.is_span() && metadata.level() == &tracing::Level::INFO
        //         })),
        // )
        // .with(tracing_subscriber::fmt::Layer::default().with_filter(LevelFilter::ERROR))
        .with(
            HierarchicalLayer::new(2)
                .with_targets(false)
                .with_indent_lines(true)
                // Note: Change this to DEBUG if you want to see more info
                .with_filter(LevelFilter::INFO),
        )
        .init();
    let _span = info_span!("running").entered();

    let manifest_dir = Path::new(env!("CARGO_MANIFEST_DIR"));
    let workspace_dir = manifest_dir.parent().unwrap();
    let crate_src = workspace_dir.join("icrate/src");

    let config = load_config(manifest_dir);

    clang_sys::load()?;
    info!(clang_version = clang::get_version());

    let clang = Clang::new()?;
    let index = Index::new(&clang, true, true);

    let developer_dir = if let Some(path) = std::env::args_os().nth(1) {
        DeveloperDirectory::from(PathBuf::from(path))
    } else {
        DeveloperDirectory::from_xcode_select()?
    };

    let sdks: Vec<_> = developer_dir
        .platforms()
        .expect("developer dir platforms")
        .into_iter()
        .map(|platform| {
            let sdks: Vec<_> = platform
                .find_sdks::<SimpleSdk>()
                .expect("platform sdks")
                .into_iter()
                .filter(|sdk| !sdk.is_symlink() && sdk.platform() == &*platform)
                .collect();
            if sdks.len() != 1 {
                panic!("found multiple sdks {sdks:?} in {:?}", &*platform);
            }
            sdks[0].sdk_path()
        })
        .collect();

    if sdks.len() != 10 {
        error!("should have one of each platform: {sdks:?}");
    }

    let mut final_result = None;

    // TODO: Compare between SDKs
    for sdk in sdks {
        // These are found using the `get_llvm_targets.fish` helper script
        let llvm_targets: &[_] = match &sdk.platform {
            Platform::MacOsX => &[
                "x86_64-apple-macosx10.12.0",
                // "arm64-apple-macosx11.0.0",
                // "i686-apple-macosx10.12.0",
            ],
            Platform::IPhoneOs => &[
                // "arm64-apple-ios10.0.0",
                // "armv7s-apple-ios10.0.0",
                // "arm64-apple-ios14.0-macabi",
                // "x86_64-apple-ios13.0-macabi",
            ],
            // Platform::IPhoneSimulator => &[
            //     "arm64-apple-ios10.0.0-simulator",
            //     "x86_64-apple-ios10.0.0-simulator",
            //     "i386-apple-ios10.0.0-simulator",
            // ],
            // Platform::AppleTvOs => &["arm64-apple-tvos", "x86_64-apple-tvos"],
            // Platform::WatchOs => &["arm64_32-apple-watchos", "armv7k-apple-watchos"],
            // Platform::WatchSimulator => &[
            //     "arm64-apple-watchos5.0.0-simulator",
            //     "x86_64-apple-watchos5.0.0-simulator",
            // ],
            _ => continue,
        };

        let mut result: Option<Output> = None;

        for llvm_target in llvm_targets {
            let _span = info_span!("parsing", platform = ?sdk.platform, llvm_target).entered();
            let curr_result = parse_sdk(&index, &sdk, llvm_target, &config);

            if let Some(prev_result) = &result {
                // Ensure that each target produces the same result.
                assert_eq!(*prev_result, curr_result);
            } else {
                result = Some(curr_result);
            }
        }

        if sdk.platform == Platform::MacOsX {
            final_result = result;
        }
    }

    let mut final_result = final_result.expect("got a result");
    let span = info_span!("analyzing").entered();
    global_analysis(&mut final_result);
    drop(span);

    let generated_dir = crate_src.join("generated");
    fs::create_dir_all(&generated_dir)?;

    for (library_name, files) in &final_result.libraries {
        let _span = info_span!("writing", library_name).entered();
        let output_path = generated_dir.join(library_name);
        fs::create_dir_all(&output_path)?;
        files.output(&output_path).unwrap();
    }

    final_result
        .output_module(&generated_dir.join("mod.rs"))
        .unwrap();

    let span = info_span!("writing features").entered();
    const FEATURE_SECTION_PATTERN:
        &str = "# This section has been automatically generated by `objc2`'s `header-translator`.\n# DO NOT EDIT\n";
    let mut cargo_toml = {
        let path = crate_src.parent().unwrap().join("Cargo.toml");
        fs::OpenOptions::new().read(true).append(true).open(path)?
    };
    // find the features section
    if let Some(pos) = {
        let mut text = String::new();
        cargo_toml.read_to_string(&mut text)?;
        text.find(FEATURE_SECTION_PATTERN)
    } {
        // truncate the file to the section header before writing the features
        let len = u64::try_from(pos + FEATURE_SECTION_PATTERN.len())?;
        cargo_toml.set_len(len)?;
    } else {
        return Err("feature section not found in icrate/Cargo.toml".into());
    }
    for (feature, required_features) in final_result.cargo_features(&config) {
        write!(cargo_toml, "{feature} = [")?;
        if !required_features.is_empty() {
            writeln!(cargo_toml)?;
        }
        for feature in required_features {
            writeln!(cargo_toml, "    \"{feature}\",")?;
        }
        writeln!(cargo_toml, "]")?;
    }
    drop(cargo_toml);
    drop(span);

    let _span = info_span!("formatting").entered();
    run_cargo_fmt("icrate");

    Ok(())
}