#include "CipherDialog.h"
#include "ui_CipherDialog.h"
#include "sqlitedb.h"

#include <QPushButton>
#include <QRegExpValidator>

#include <QtCore/qmath.h>

CipherDialog::CipherDialog(QWidget* parent, bool encrypt) :
 QDialog(parent),
 ui(new Ui::CipherDialog),
 encryptMode(encrypt),
 rawKeyValidator(new QRegExpValidator(QRegExp("0x[a-fA-F0-9]+")))
{
 ui->setupUi(this);

 int minimumPageSizeExponent = 9;
 int maximumPageSizeExponent = 16;
 int defaultPageSizeExponent = 10;

 for(int exponent = minimumPageSizeExponent; exponent <= maximumPageSizeExponent; exponent++)
 {
 int pageSize = static_cast<int>(qPow(2, exponent));
 ui->comboPageSize->addItem(QLocale().toString(pageSize), pageSize);

 if (exponent == defaultPageSizeExponent)
 ui->comboPageSize->setCurrentIndex(exponent - minimumPageSizeExponent);
 }

 ui->comboPageSize->setMinimumWidth(ui->editPassword->width());

 if(encrypt)
 {
 ui->labelDialogDescription->setText(tr("Please set a key to encrypt the database.\nNote that if you change any of the other, optional, settings you'll need "
 "to re-enter them as well every time you open the database file.\nLeave the password fields empty to disable the "
 "encryption.\nThe encryption process might take some time and you should have a backup copy of your database! Unsaved "
 "changes are applied before modifying the encryption."));
 } else {
 ui->labelDialogDescription->setText(tr("Please enter the key used to encrypt the database.\nIf any of the other settings were altered for this database file "
 "you need to provide this information as well."));
 ui->editPassword2->setVisible(false);
 ui->labelPassword2->setVisible(false);
 }

 // Set the default encryption settings depending on the SQLCipher version we use
 QString sqlite_version, sqlcipher_version;
 DBBrowserDB::getSqliteVersion(sqlite_version, sqlcipher_version);
 if(sqlcipher_version.startsWith('4'))
 ui->radioEncryptionSqlCipher4->setChecked(true);
 else
 ui->radioEncryptionSqlCipher3->setChecked(true);
}

CipherDialog::~CipherDialog()
{
 delete rawKeyValidator;
 delete ui;
}

CipherSettings CipherDialog::getCipherSettings() const
{
 CipherSettings::KeyFormats keyFormat = CipherSettings::getKeyFormat(ui->comboKeyFormat->currentIndex());
 QString password = ui->editPassword->text();
 int pageSize = ui->comboPageSize->itemData(ui->comboPageSize->currentIndex()).toInt();

 CipherSettings cipherSettings;

 cipherSettings.setKeyFormat(keyFormat);
 cipherSettings.setPassword(password);
 cipherSettings.setPageSize(pageSize);
 cipherSettings.setKdfIterations(ui->spinKdfIterations->value());
 cipherSettings.setHmacAlgorithm(QString("HMAC_") + ui->comboHmacAlgorithm->currentText());
 cipherSettings.setKdfAlgorithm(QString("PBKDF2_HMAC_") + ui->comboKdfAlgorithm->currentText());

 return cipherSettings;
}

void CipherDialog::checkInputFields()
{
 if(sender() == ui->comboKeyFormat)
 {
 CipherSettings::KeyFormats keyFormat = CipherSettings::getKeyFormat(ui->comboKeyFormat->currentIndex());

 if(keyFormat == CipherSettings::KeyFormats::Passphrase)
 {
 ui->editPassword->setValidator(nullptr);
 ui->editPassword2->setValidator(nullptr);
 ui->editPassword->setPlaceholderText("");
 } else if(keyFormat == CipherSettings::KeyFormats::RawKey) {
 ui->editPassword->setValidator(rawKeyValidator);
 ui->editPassword2->setValidator(rawKeyValidator);
 ui->editPassword->setPlaceholderText("0x...");
 }

 ui->editPassword->setText("");
 ui->editPassword2->setText("");
 }

 bool valid = true;
 if(encryptMode)
 valid = ui->editPassword->text() == ui->editPassword2->text();

 ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(valid);
}

void CipherDialog::toggleEncryptionSettings()
{
 if(ui->radioEncryptionSqlCipher3->isChecked())
 {
 // SQLCipher3
 ui->comboPageSize->setCurrentText(QLocale().toString(1024));
 ui->spinKdfIterations->setValue(64000);
 ui->comboHmacAlgorithm->setCurrentText("SHA1");
 ui->comboKdfAlgorithm->setCurrentText("SHA1");

 ui->comboPageSize->setEnabled(false);
 ui->spinKdfIterations->setEnabled(false);
 ui->comboHmacAlgorithm->setEnabled(false);
 ui->comboKdfAlgorithm->setEnabled(false);
 } else if(ui->radioEncryptionSqlCipher4->isChecked()) {
 // SQLCipher4
 ui->comboPageSize->setCurrentText(QLocale().toString(4096));
 ui->spinKdfIterations->setValue(256000);
 ui->comboHmacAlgorithm->setCurrentText("SHA512");
 ui->comboKdfAlgorithm->setCurrentText("SHA512");

 ui->comboPageSize->setEnabled(false);
 ui->spinKdfIterations->setEnabled(false);
 ui->comboHmacAlgorithm->setEnabled(false);
 ui->comboKdfAlgorithm->setEnabled(false);
 } else if(ui->radioEncryptionCustom->isChecked()) {
 // Custom

 ui->comboPageSize->setEnabled(true);
 ui->spinKdfIterations->setEnabled(true);
 ui->comboHmacAlgorithm->setEnabled(true);
 ui->comboKdfAlgorithm->setEnabled(true);
 }
}