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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * The Universal Permissive License (UPL), Version 1.0
 *
 * Subject to the condition set forth below, permission is hereby granted to any
 * person obtaining a copy of this software, associated documentation and/or
 * data (collectively the "Software"), free of charge and under any and all
 * copyright rights in the Software, and any and all patent rights owned or
 * freely licensable by each licensor hereunder covering either (i) the
 * unmodified Software as contributed to or provided by such licensor, or (ii)
 * the Larger Works (as defined below), to deal in both
 *
 * (a) the Software, and
 *
 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
 * one is included with the Software each a "Larger Work" to which the Software
 * is contributed by such licensors),
 *
 * without restriction, including without limitation the rights to copy, create
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 * Software and the Larger Work(s), and to sublicense the foregoing rights on
 * either these or other terms.
 *
 * This license is subject to the following condition:
 *
 * The above copyright notice and either this complete permission notice or at a
 * minimum a reference to the UPL must be included in all copies or substantial
 * portions of the Software.
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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package org.graalvm.wasm;

import com.oracle.truffle.api.CallTarget;
import com.oracle.truffle.api.Truffle;
import com.oracle.truffle.api.TruffleLanguage;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.nodes.RootNode;
import org.graalvm.options.OptionDescriptors;
import org.graalvm.wasm.api.WebAssembly;
import org.graalvm.wasm.memory.UnsafeWasmMemory;
import org.graalvm.wasm.memory.WasmMemory;

@TruffleLanguage.Registration(id = "wasm", name = "WebAssembly", defaultMimeType = "application/wasm", byteMimeTypes = "application/wasm", contextPolicy = TruffleLanguage.ContextPolicy.EXCLUSIVE, fileTypeDetectors = WasmFileDetector.class, //
                interactive = false)
public final class WasmLanguage extends TruffleLanguage<WasmContext> {
    private boolean isFirst = true;

    @Override
    protected WasmContext createContext(Env env) {
        WasmContext context = new WasmContext(env, this);
        if (env.isPolyglotBindingsAccessAllowed()) {
            env.exportSymbol("WebAssembly", new WebAssembly(context));
        }
        return context;
    }

    @Override
    protected CallTarget parse(ParsingRequest request) {
        final WasmContext context = getCurrentContext();
        final String moduleName = isFirst ? "main" : request.getSource().getName();
        isFirst = false;
        final byte[] data = request.getSource().getBytes().toByteArray();
        final WasmModule module = context.readModule(moduleName, data, null);
        final WasmInstance instance = context.readInstance(module);
        return Truffle.getRuntime().createCallTarget(new RootNode(this) {
            @Override
            public WasmInstance execute(VirtualFrame frame) {
                return instance;
            }
        });
    }

    @Override
    protected Object getScope(WasmContext context) {
        return context.getScope();
    }

    @Override
    protected OptionDescriptors getOptionDescriptors() {
        return new WasmOptionsOptionDescriptors();
    }

    static WasmContext getCurrentContext() {
        return getCurrentContext(WasmLanguage.class);
    }

    @Override
    protected void finalizeContext(WasmContext context) {
        super.finalizeContext(context);
        for (int i = 0; i < context.memories().count(); ++i) {
            final WasmMemory memory = context.memories().memory(i);
            if (memory instanceof UnsafeWasmMemory) {
                ((UnsafeWasmMemory) memory).free();
            }
        }
    }
}