//! CLI tool to run wast tests using the wasmtime libraries.

#![deny(
    missing_docs,
    trivial_numeric_casts,
    unused_extern_crates,
    unstable_features
)]
#![warn(unused_import_braces)]
#![cfg_attr(feature = "clippy", plugin(clippy(conf_file = "../../clippy.toml")))]
#![cfg_attr(
    feature = "cargo-clippy",
    allow(clippy::new_without_default, clippy::new_without_default_derive)
)]
#![cfg_attr(
    feature = "cargo-clippy",
    warn(
        clippy::float_arithmetic,
        clippy::mut_mut,
        clippy::nonminimal_bool,
        clippy::option_map_unwrap_or,
        clippy::option_map_unwrap_or_else,
        clippy::unicode_not_nfc,
        clippy::use_self
    )
)]

use cranelift_codegen::settings;
use cranelift_codegen::settings::Configurable;
use cranelift_native;
use docopt::Docopt;
use pretty_env_logger;
use serde::Deserialize;
use std::path::Path;
use std::process;
use wasmtime_environ::{cache_create_new_config, cache_init};
use wasmtime_jit::{CompilationStrategy, Compiler, Features};
use wasmtime_wast::WastContext;

const USAGE: &str = "
Wast test runner.

Usage:
    wast [-do] [--enable-simd] [--disable-cache | --cache-config=<cache_config_file>] [--always-lightbeam | --always-cranelift] <file>...
    wast --create-cache-config [--cache-config=<cache_config_file>]
    wast --help | --version

Options:
    -h, --help          print this help message
    --version           print the Cranelift version
    -o, --optimize      runs optimization passes on the translated functions
    --disable-cache     disables cache system
    --cache-config=<cache_config_file>
                        use specified cache configuration;
                        can be used with --create-cache-config to specify custom file
    --create-cache-config
                        creates default configuration and writes it to the disk,
                        use with --cache-config to specify custom config file
                        instead of default one
    --always-lightbeam  use Lightbeam for all compilation
    --always-cranelift  use Cranelift for all compilation
    -d, --debug         enable debug output on stderr/stdout
    --enable-simd       enable proposed SIMD instructions
";

#[derive(Deserialize, Debug, Clone)]
struct Args {
    arg_file: Vec<String>,
    flag_debug: bool,
    flag_function: Option<String>,
    flag_optimize: bool,
    flag_disable_cache: bool,
    flag_cache_config: Option<String>,
    flag_create_cache_config: bool,
    flag_enable_simd: bool,
    flag_always_lightbeam: bool,
    flag_always_cranelift: bool,
}

fn main() {
    let version = env!("CARGO_PKG_VERSION");
    let args: Args = Docopt::new(USAGE)
        .and_then(|d| {
            d.help(true)
                .version(Some(String::from(version)))
                .deserialize()
        })
        .unwrap_or_else(|e| e.exit());

    let log_config = if args.flag_debug {
        pretty_env_logger::init();
        None
    } else {
        let prefix = "cranelift.dbg.";
        wasmtime::init_file_per_thread_logger(prefix);
        Some(prefix)
    };

    if args.flag_create_cache_config {
        match cache_create_new_config(args.flag_cache_config) {
            Ok(path) => {
                println!(
                    "Successfully created new configuation file at {}",
                    path.display()
                );
                return;
            }
            Err(err) => {
                eprintln!("Error: {}", err);
                process::exit(1);
            }
        }
    }

    let errors = cache_init(
        !args.flag_disable_cache,
        args.flag_cache_config.as_ref(),
        log_config,
    );

    if !errors.is_empty() {
        eprintln!("Cache initialization failed. Errors:");
        for e in errors {
            eprintln!("-> {}", e);
        }
        process::exit(1);
    }

    let isa_builder = cranelift_native::builder().unwrap_or_else(|_| {
        panic!("host machine is not a supported target");
    });
    let mut flag_builder = settings::builder();
    let mut features: Features = Default::default();

    // There are two possible traps for division, and this way
    // we get the proper one if code traps.
    flag_builder.enable("avoid_div_traps").unwrap();

    // Enable verifier passes in debug mode.
    if cfg!(debug_assertions) {
        flag_builder.enable("enable_verifier").unwrap();
    }

    // Enable optimization if requested.
    if args.flag_optimize {
        flag_builder.set("opt_level", "best").unwrap();
    }

    // Enable SIMD if requested
    if args.flag_enable_simd {
        flag_builder.enable("enable_simd").unwrap();
        features.simd = true;
    }

    // Decide how to compile.
    let strategy = match (args.flag_always_lightbeam, args.flag_always_cranelift) {
        #[cfg(feature = "lightbeam")]
        (true, false) => CompilationStrategy::AlwaysLightbeam,
        #[cfg(not(feature = "lightbeam"))]
        (true, false) => panic!("--always-lightbeam given, but Lightbeam support is not enabled"),
        (false, true) => CompilationStrategy::AlwaysCranelift,
        (false, false) => CompilationStrategy::Auto,
        (true, true) => {
            panic!("Can't enable --always-cranelift and --always-lightbeam at the same time")
        }
    };

    let isa = isa_builder.finish(settings::Flags::new(flag_builder));
    let engine = Compiler::new(isa, strategy);
    let mut wast_context = WastContext::new(Box::new(engine)).with_features(features);

    wast_context
        .register_spectest()
        .expect("error instantiating \"spectest\"");

    for filename in &args.arg_file {
        wast_context
            .run_file(Path::new(&filename))
            .unwrap_or_else(|e| {
                eprintln!("{}", e);
                process::exit(1)
            });
    }
}