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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
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 *
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package compiler.lib.ir_framework.driver.irmatching.parser;

import compiler.lib.ir_framework.TestFramework;
import compiler.lib.ir_framework.shared.TestFrameworkException;
import compiler.lib.ir_framework.test.VMInfoPrinter;

import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Class to parse the VMInfo emitted by the test VM and creating {@link VMInfo} objects for each entry.
 *
 * @see VMInfo
 */
public class VMInfoParser {

    private static final Pattern VM_INFO_PATTERN =
            Pattern.compile("(?<=" + VMInfoPrinter.START_VM_INFO + "\r?\n).*\\R([\\s\\S]*)(?=" + VMInfoPrinter.END_VM_INFO + ")");

    /**
     * Extract VMInfo from the irEncoding.
     */
    public static VMInfo parseVMInfo(String irEncoding) {
        Map<String, String> map = new HashMap<>();
        String[] lines = getVMInfoLines(irEncoding);
        for (String s : lines) {
            String line = s.trim();
            String[] splitLine = line.split(":", 2);
            if (splitLine.length != 2) {
                throw new TestFrameworkException("Invalid VMInfo key:value encoding. Found: " + splitLine[0]);
            }
            String key = splitLine[0];
            String value = splitLine[1];
            map.put(key, value);
        }
        return new VMInfo(map);
    }

    /**
     * Extract the VMInfo from the irEncoding string, strip away the header and return the individual key-value lines.
     */
    private static String[] getVMInfoLines(String irEncoding) {
        Matcher matcher = VM_INFO_PATTERN.matcher(irEncoding);
        TestFramework.check(matcher.find(), "Did not find VMInfo in:" + System.lineSeparator() + irEncoding);
        String lines = matcher.group(1).trim();
        if (lines.isEmpty()) {
            // Nothing to IR match.
            return new String[0];
        }
        return lines.split("\\R");
    }
}