pindialog.cpp

#include "pindialog.h"

#include <QApplication>
#include <QCryptographicHash>
#include <QGraphicsDropShadowEffect>
#include <QHBoxLayout>
#include <QLabel>
#include <QLineEdit>
#include <QPushButton>
#include <QSettings>
#include <QVBoxLayout>

// ── helpers ──────────────────────────────────────────────

static QString hashPin(const QString &pin) {
    // SHA-256 with a fixed app salt
    QByteArray salted = QByteArray("CipherVault::PIN::") + pin.toUtf8();
    return QString::fromLatin1(
        QCryptographicHash::hash(salted, QCryptographicHash::Sha256).toHex());
}

static void saveHash(const QString &hash) {
    QSettings s;
    s.setValue("security/pinHash", hash);
}

static QString loadHash() {
    QSettings s;
    return s.value("security/pinHash").toString();
}

// ── static API ───────────────────────────────────────────

bool PinDialog::isPinSet() {
    return !loadHash().isEmpty();
}

bool PinDialog::verifyPin() {
    PinDialog dlg(Verify);
    return dlg.exec() == QDialog::Accepted;
}

bool PinDialog::setupPin() {
    PinDialog dlg(Setup);
    return dlg.exec() == QDialog::Accepted;
}

bool PinDialog::changePin(QWidget *parent) {
    // First verify old PIN
    PinDialog verify(Verify, parent);
    verify.setWindowTitle("Verify Current PIN");
    if (verify.exec() != QDialog::Accepted)
        return false;

    // Then set new one
    PinDialog setup(Setup, parent);
    setup.setWindowTitle("Set New PIN");
    return setup.exec() == QDialog::Accepted;
}

// ── constructor ──────────────────────────────────────────

PinDialog::PinDialog(Mode mode, QWidget *parent)
    : QDialog(parent), m_mode(mode) {
    setWindowFlags(Qt::Dialog | Qt::FramelessWindowHint);
    setAttribute(Qt::WA_TranslucentBackground);
    setFixedSize(420, 380);
    buildUi();
}

void PinDialog::buildUi() {
    auto *outer = new QVBoxLayout(this);
    outer->setContentsMargins(0, 0, 0, 0);

    // Card container
    auto *card = new QWidget;
    card->setObjectName("pinCard");
    card->setStyleSheet(
        "#pinCard {"
        "  background: qlineargradient(x1:0,y1:0,x2:0,y2:1,"
        "    stop:0 #0f1318, stop:1 #080c14);"
        "  border: 1px solid rgba(0, 212, 255, 0.25);"
        "  border-radius: 16px;"
        "}");

    auto *glow = new QGraphicsDropShadowEffect;
    glow->setBlurRadius(40);
    glow->setColor(QColor(0, 212, 255, 50));
    glow->setOffset(0, 0);
    card->setGraphicsEffect(glow);

    auto *lay = new QVBoxLayout(card);
    lay->setContentsMargins(36, 32, 36, 32);
    lay->setSpacing(16);
    lay->setAlignment(Qt::AlignCenter);

    // Lock icon
    auto *icon = new QLabel(QString::fromUtf8("🔐"));
    icon->setAlignment(Qt::AlignCenter);
    icon->setStyleSheet("font-size: 48px; padding: 0;");
    lay->addWidget(icon);

    // Title
    m_title = new QLabel(m_mode == Setup ? "SET YOUR PIN" : "ENTER PIN");
    m_title->setAlignment(Qt::AlignCenter);
    m_title->setStyleSheet(
        "font-size: 20px; font-weight: 800; color: #00d4ff;"
        "letter-spacing: 4px;");
    lay->addWidget(m_title);

    // Subtitle
    m_subtitle = new QLabel(
        m_mode == Setup
            ? "Create a 4-8 digit PIN to secure the app"
            : "Enter your PIN to unlock CipherVault");
    m_subtitle->setAlignment(Qt::AlignCenter);
    m_subtitle->setWordWrap(true);
    m_subtitle->setStyleSheet("font-size: 12px; color: #7d8590;");
    lay->addWidget(m_subtitle);

    lay->addSpacing(8);

    // PIN input
    m_pinInput = new QLineEdit;
    m_pinInput->setEchoMode(QLineEdit::Password);
    m_pinInput->setMaxLength(8);
    m_pinInput->setAlignment(Qt::AlignCenter);
    m_pinInput->setPlaceholderText(m_mode == Setup ? "New PIN" : "PIN");
    m_pinInput->setStyleSheet(
        "QLineEdit {"
        "  background: #181c2f; border: 1px solid #2a3050;"
        "  border-radius: 8px; padding: 12px; color: #e6edf3;"
        "  font-size: 22px; letter-spacing: 12px;"
        "}"
        "QLineEdit:focus { border-color: #00d4ff; }");
    lay->addWidget(m_pinInput);

    // Confirm input (setup mode only)
    m_pinConfirm = new QLineEdit;
    m_pinConfirm->setEchoMode(QLineEdit::Password);
    m_pinConfirm->setMaxLength(8);
    m_pinConfirm->setAlignment(Qt::AlignCenter);
    m_pinConfirm->setPlaceholderText("Confirm PIN");
    m_pinConfirm->setStyleSheet(m_pinInput->styleSheet());
    m_pinConfirm->setVisible(m_mode == Setup);
    lay->addWidget(m_pinConfirm);

    // Error label
    m_errorLabel = new QLabel;
    m_errorLabel->setAlignment(Qt::AlignCenter);
    m_errorLabel->setStyleSheet("color: #ff4466; font-size: 12px; font-weight: 600;");
    m_errorLabel->setVisible(false);
    lay->addWidget(m_errorLabel);

    // Submit button
    m_submitBtn = new QPushButton(m_mode == Setup ? "SET PIN" : QString::fromUtf8("UNLOCK  🔓"));
    m_submitBtn->setCursor(Qt::PointingHandCursor);
    m_submitBtn->setMinimumHeight(44);
    m_submitBtn->setStyleSheet(
        "QPushButton {"
        "  background: qlineargradient(x1:0,y1:0,x2:1,y2:0,"
        "    stop:0 #00d4ff, stop:1 #00a8cc);"
        "  color: #000; font-weight: 700; font-size: 14px;"
        "  border: none; border-radius: 8px; padding: 10px 28px;"
        "  letter-spacing: 2px;"
        "}"
        "QPushButton:hover {"
        "  background: qlineargradient(x1:0,y1:0,x2:1,y2:0,"
        "    stop:0 #33e0ff, stop:1 #00d4ff);"
        "}");
    lay->addWidget(m_submitBtn);

    // Skip button for setup only
    if (m_mode == Setup) {
        auto *skipBtn = new QPushButton("Skip for now");
        skipBtn->setCursor(Qt::PointingHandCursor);
        skipBtn->setStyleSheet(
            "QPushButton { background: none; border: none; color: #3d4450;"
            "  font-size: 12px; }"
            "QPushButton:hover { color: #7d8590; }");
        connect(skipBtn, &QPushButton::clicked, this, [this]() {
            accept(); // allow entry without setting PIN
        });
        lay->addWidget(skipBtn, 0, Qt::AlignCenter);
    }

    outer->addWidget(card);

    // Connections
    connect(m_submitBtn, &QPushButton::clicked, this, &PinDialog::onSubmit);
    connect(m_pinInput, &QLineEdit::returnPressed, this, &PinDialog::onSubmit);
    connect(m_pinConfirm, &QLineEdit::returnPressed, this, &PinDialog::onSubmit);

    m_pinInput->setFocus();
}

void PinDialog::onSubmit() {
    QString pin = m_pinInput->text();

    if (pin.length() < 4) {
        m_errorLabel->setText("PIN must be at least 4 digits");
        m_errorLabel->setVisible(true);
        return;
    }

    // Digits only
    for (const auto &ch : pin) {
        if (!ch.isDigit()) {
            m_errorLabel->setText("PIN must contain only digits");
            m_errorLabel->setVisible(true);
            return;
        }
    }

    if (m_mode == Setup) {
        if (pin != m_pinConfirm->text()) {
            m_errorLabel->setText("PINs do not match");
            m_errorLabel->setVisible(true);
            m_pinConfirm->clear();
            m_pinConfirm->setFocus();
            return;
        }
        saveHash(hashPin(pin));
        accept();
    } else {
        // Verify
        if (hashPin(pin) == loadHash()) {
            accept();
        } else {
            m_errorLabel->setText("Incorrect PIN");
            m_errorLabel->setVisible(true);
            m_pinInput->clear();
            m_pinInput->setFocus();
        }
    }
}