/**
 * test_signal_editing.cpp — Tests for Step 3: signal ↔ frame byte sync.
 * Tests bit packing/unpacking and signal value editing.
 */

#include <QtTest/QtTest>
#include <QTreeWidget>
#include <QTreeWidgetItem>
#include "main_window.h"

#ifndef LDF_SAMPLE_PATH
#error "LDF_SAMPLE_PATH must be defined by CMake"
#endif

class TestSignalEditing : public QObject
{
    Q_OBJECT

private:
    MainWindow* m_window;

private slots:
    void init()
    {
        m_window = new MainWindow();
        m_window->loadLdfFile(QString(LDF_SAMPLE_PATH));
    }
    void cleanup() { delete m_window; m_window = nullptr; }

    // ─── Bit Packing Unit Tests ───────────────────────────────────

    void test_packSingleBit()
    {
        QVector<int> buf = {0, 0};
        MainWindow::packSignal(buf, 0, 1, 1);
        QCOMPARE(buf[0], 0x01);
    }

    void test_packByteAtOffset8()
    {
        QVector<int> buf = {0, 0};
        MainWindow::packSignal(buf, 8, 8, 0x80);
        QCOMPARE(buf[1], 0x80);
    }

    void test_pack2bitAtOffset1()
    {
        QVector<int> buf = {0, 0};
        MainWindow::packSignal(buf, 1, 2, 3);
        QCOMPARE(buf[0], 0x06);
    }

    void test_packMultipleSignals()
    {
        QVector<int> buf = {0, 0};
        MainWindow::packSignal(buf, 0, 1, 1);   // MotorEnable
        MainWindow::packSignal(buf, 1, 2, 2);   // MotorDirection
        MainWindow::packSignal(buf, 8, 8, 128);  // MotorSpeed
        QCOMPARE(buf[0], 0x05);
        QCOMPARE(buf[1], 0x80);
    }

    void test_extractSingleBit()
    {
        QVector<int> buf = {0x01, 0};
        QCOMPARE(MainWindow::extractSignal(buf, 0, 1), 1);
    }

    void test_extractByteAtOffset8()
    {
        QVector<int> buf = {0, 0x80};
        QCOMPARE(MainWindow::extractSignal(buf, 8, 8), 0x80);
    }

    void test_extract2bitAtOffset1()
    {
        QVector<int> buf = {0x06, 0};
        QCOMPARE(MainWindow::extractSignal(buf, 1, 2), 3);
    }

    void test_packThenExtractRoundtrip()
    {
        QVector<int> buf = {0, 0};
        MainWindow::packSignal(buf, 8, 8, 200);
        QCOMPARE(MainWindow::extractSignal(buf, 8, 8), 200);
    }

    // ─── Signal Value Editing ─────────────────────────────────────

    void test_editSignalUpdatesFrameBytes()
    {
        auto* frameItem = m_window->txTable()->topLevelItem(0);
        auto* speedSig = frameItem->child(2);  // MotorSpeed (bit 8, width 8)

        // Simulate user edit
        speedSig->setText(4, "128");

        // Frame bytes should reflect MotorSpeed=128
        QVariantList bytes = frameItem->data(4, Qt::UserRole).toList();
        QCOMPARE(bytes[1].toInt(), 128);
    }

    void test_editSignalPreservesOtherSignals()
    {
        auto* frameItem = m_window->txTable()->topLevelItem(0);
        auto* enableSig = frameItem->child(0);
        auto* speedSig = frameItem->child(2);

        enableSig->setText(4, "1");
        speedSig->setText(4, "255");

        QVariantList bytes = frameItem->data(4, Qt::UserRole).toList();
        QVERIFY(bytes[0].toInt() & 0x01);  // MotorEnable still 1
        QCOMPARE(bytes[1].toInt(), 255);
    }

    void test_signalValueClampedToWidth()
    {
        auto* frameItem = m_window->txTable()->topLevelItem(0);
        auto* enableSig = frameItem->child(0);  // width 1, max = 1

        enableSig->setText(4, "5");

        int stored = enableSig->data(4, Qt::UserRole).toInt();
        QVERIFY(stored <= 1);
    }

    // ─── Frame Value Editing ──────────────────────────────────────

    void test_editFrameBytesUpdatesSignals()
    {
        auto* frameItem = m_window->txTable()->topLevelItem(0);

        frameItem->setText(4, "05 C8");

        // MotorEnable (bit 0, w1) = 1
        QCOMPARE(frameItem->child(0)->data(4, Qt::UserRole).toInt(), 1);
        // MotorDirection (bit 1, w2) = 2
        QCOMPARE(frameItem->child(1)->data(4, Qt::UserRole).toInt(), 2);
        // MotorSpeed (bit 8, w8) = 200
        QCOMPARE(frameItem->child(2)->data(4, Qt::UserRole).toInt(), 200);
    }

    void test_editFrameBytesInvalidReverts()
    {
        auto* frameItem = m_window->txTable()->topLevelItem(0);

        QVariantList oldBytes = frameItem->data(4, Qt::UserRole).toList();

        frameItem->setText(4, "not valid hex");

        QVariantList newBytes = frameItem->data(4, Qt::UserRole).toList();
        QCOMPARE(newBytes, oldBytes);
    }
};

QTEST_MAIN(TestSignalEditing)
#include "test_signal_editing.moc"