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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package org.graalvm.wasm.utils;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.StandardOpenOption;
import java.util.function.Supplier;
import java.util.stream.Collectors;

public class WasmBinaryTools {

    private static Supplier<String> asyncReadInputStream(InputStream is) {
        class SupplierThread extends Thread implements Supplier<String> {
            private String result = null;

            @Override
            public String get() {
                try {
                    this.join();
                } catch (InterruptedException e) {
                    throw new RuntimeException();
                }
                return result;
            }

            @Override
            public void run() {
                result = new BufferedReader(new InputStreamReader(is)).lines().collect(Collectors.joining(System.lineSeparator()));
            }
        }
        final SupplierThread supplier = new SupplierThread();
        supplier.start();
        return supplier;
    }

    private static void runExternalToolAndVerify(String message, String[] commandLine) throws IOException, InterruptedException {
        Runtime runtime = Runtime.getRuntime();
        Process process = runtime.exec(commandLine);
        Supplier<String> stdout = asyncReadInputStream(process.getInputStream());
        Supplier<String> stderr = asyncReadInputStream(process.getErrorStream());
        int exitCode = process.waitFor();
        if (exitCode != 0) {
            Assert.fail(Assert.format("%s ('%s', exit code %d)\nstderr:\n%s\nstdout:\n%s", message, String.join(" ", commandLine), exitCode, stderr.get(), stdout.get()));
        }
    }

    private static byte[] wat2wasm(File input, File output) throws IOException, InterruptedException {
        Assert.assertNotNull(
                        Assert.format("The %s property must be set in order to be able to compile .wat to .wasm", SystemProperties.WAT_TO_WASM_EXECUTABLE_PROPERTY_NAME),
                        SystemProperties.WAT_TO_WASM_EXECUTABLE);
        // execute the wat2wasm tool and wait for it to finish execution
        runExternalToolAndVerify(
                        "wat2wasm compilation failed",
                        new String[]{
                                        SystemProperties.WAT_TO_WASM_EXECUTABLE,
                                        input.getPath(),
                                        // This option is needed so that wat2wasm agrees to generate
                                        // invalid wasm files.
                                        "-v",
                                        "--no-check",
                                        "-o",
                                        output.getPath(),
                        });
        // read the resulting binary, delete the temporary files and return
        return Files.readAllBytes(output.toPath());
    }

    public static byte[] compileWat(File watFile) throws IOException, InterruptedException {
        File wasmFile = File.createTempFile("wasm-bin-", ".wasm");
        byte[] binary = wat2wasm(watFile, wasmFile);
        wasmFile.deleteOnExit();
        return binary;
    }

    public static byte[] compileWat(String name, String program) throws IOException, InterruptedException {
        // create two temporary files for the text and the binary, write the given program to the
        // first one
        File watFile = File.createTempFile(name + "-wasm-text-", ".wat");
        File wasmFile = File.createTempFile(name + "-wasm-bin-", ".wasm");
        Files.write(watFile.toPath(), program.getBytes(StandardCharsets.UTF_8), StandardOpenOption.WRITE);
        // read the resulting binary, delete the temporary files and return
        byte[] binary = wat2wasm(watFile, wasmFile);
        watFile.deleteOnExit();
        wasmFile.deleteOnExit();
        return binary;
    }
}