// SPDX-License-Identifier: GPL-3.0-or-later
// SPDX-FileCopyrightText: 2026 A-La-Karte Contributors

#include "processscanner.h"

#include <QElapsedTimer>
#include <QFileInfo>
#include <QProcess>
#include <QProcessEnvironment>
#include <QStandardPaths>
#include <QString>
#include <QUuid>
#include <QtTest>

#include <atomic>
#include <utility>

class ProcessScannerTest : public QObject
{
    Q_OBJECT

private Q_SLOTS:
    void initTestCase();
    void cleanupTestCase();

    void scanFindsEnvAndCmdline();
    void preferEnvironmentMatchesFilters();
    void cancelledScanReturnsEmpty();

private:
    QString m_shell;
    QString m_marker;
    QProcess m_envProc;
    QProcess m_cmdProc;

    static bool containsPid(const QList<ProcessScanner::Match> &matches, qint64 pid)
    {
        for (const auto &m : matches) {
            if (m.pid == static_cast<uint>(pid)) {
                return true;
            }
        }
        return false;
    }

    static const ProcessScanner::Match *findByPid(const QList<ProcessScanner::Match> &matches, qint64 pid)
    {
        for (const auto &m : matches) {
            if (m.pid == static_cast<uint>(pid)) {
                return &m;
            }
        }
        return nullptr;
    }

    static bool waitForScan(std::function<bool()> predicate, int timeoutMs)
    {
        QElapsedTimer t;
        t.start();
        while (t.elapsed() < timeoutMs) {
            if (predicate()) {
                return true;
            }
            QTest::qWait(50);
        }
        return false;
    }

    void startProcesses();
    void stopProcess(QProcess &p);
};

void ProcessScannerTest::initTestCase()
{
    if (!QFileInfo(QStringLiteral("/proc")).isDir()) {
        QSKIP("/proc not available");
    }

    m_shell = QStandardPaths::findExecutable(QStringLiteral("sh"));
    if (m_shell.isEmpty()) {
        QSKIP("sh not found");
    }

    m_marker = QUuid::createUuid().toString(QUuid::WithoutBraces);
    startProcesses();
}

void ProcessScannerTest::cleanupTestCase()
{
    stopProcess(m_envProc);
    stopProcess(m_cmdProc);
}

void ProcessScannerTest::startProcesses()
{
    const QString script = QStringLiteral("while true; do sleep 60; done # %1").arg(m_marker);

    {
        QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
        env.insert(QStringLiteral("ALAKARTE_PROCESSSCANNER_TEST_MARKER"), m_marker);
        m_envProc.setProcessEnvironment(env);
        m_envProc.start(m_shell, {QStringLiteral("-c"), script});
        QVERIFY2(m_envProc.waitForStarted(5000), qPrintable(m_envProc.errorString()));
        QVERIFY(m_envProc.processId() > 0);
    }

    {
        QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
        m_cmdProc.setProcessEnvironment(env);
        m_cmdProc.start(m_shell, {QStringLiteral("-c"), script});
        QVERIFY2(m_cmdProc.waitForStarted(5000), qPrintable(m_cmdProc.errorString()));
        QVERIFY(m_cmdProc.processId() > 0);
    }
}

void ProcessScannerTest::stopProcess(QProcess &p)
{
    if (p.state() == QProcess::NotRunning) {
        return;
    }

    p.terminate();
    if (!p.waitForFinished(3000)) {
        p.kill();
        p.waitForFinished(3000);
    }
}

void ProcessScannerTest::scanFindsEnvAndCmdline()
{
    QVERIFY(m_envProc.processId() > 0);
    QVERIFY(m_cmdProc.processId() > 0);

    ProcessScanner::ScanOptions opts;
    opts.envKeys = {QStringLiteral("ALAKARTE_PROCESSSCANNER_TEST_MARKER")};
    opts.envValue = m_marker;
    opts.cmdlineSubstring = m_marker;
    opts.preferEnvironmentMatches = false;

    QList<ProcessScanner::Match> results;
    const bool ok = waitForScan(
        [&]() {
            results = ProcessScanner::scan(opts);
            return containsPid(results, m_envProc.processId()) && containsPid(results, m_cmdProc.processId());
        },
        5000);

    QVERIFY(ok);

    const auto *envMatch = findByPid(results, m_envProc.processId());
    QVERIFY(envMatch);
    QVERIFY(envMatch->envMatched);

    const auto *cmdMatch = findByPid(results, m_cmdProc.processId());
    QVERIFY(cmdMatch);
    QVERIFY(!cmdMatch->envMatched);
}

void ProcessScannerTest::preferEnvironmentMatchesFilters()
{
    QVERIFY(m_envProc.processId() > 0);
    QVERIFY(m_cmdProc.processId() > 0);

    ProcessScanner::ScanOptions opts;
    opts.envKeys = {QStringLiteral("ALAKARTE_PROCESSSCANNER_TEST_MARKER")};
    opts.envValue = m_marker;
    opts.cmdlineSubstring = m_marker;
    opts.preferEnvironmentMatches = true;

    QList<ProcessScanner::Match> results;
    const bool ok = waitForScan(
        [&]() {
            results = ProcessScanner::scan(opts);
            return containsPid(results, m_envProc.processId());
        },
        5000);

    QVERIFY(ok);
    QVERIFY(containsPid(results, m_envProc.processId()));
    QVERIFY(!containsPid(results, m_cmdProc.processId()));

    for (const auto &m : std::as_const(results)) {
        QVERIFY(m.envMatched);
    }
}

void ProcessScannerTest::cancelledScanReturnsEmpty()
{
    ProcessScanner::ScanOptions opts;
    opts.envKeys = {QStringLiteral("ALAKARTE_PROCESSSCANNER_TEST_MARKER")};
    opts.envValue = m_marker;
    opts.cmdlineSubstring = m_marker;
    opts.preferEnvironmentMatches = false;

    const std::atomic_bool cancelled(true);
    const QList<ProcessScanner::Match> results = ProcessScanner::scan(opts, cancelled);
    QVERIFY(results.isEmpty());
}

QTEST_MAIN(ProcessScannerTest)

#include "processscanner_test.moc"