/*
 * Copyright (C) 2006 Dmitry Morozhnikov <dmiceman@mail.ru>
 * Copyright (C) 2011-2020 Laurent Montel <montel@kde.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */

#include "customtemplates.h"
#include "templateparser/templatesinsertcommandpushbutton.h"
#include "customtemplates_kfg.h"
#include "globalsettings_templateparser.h"
#include "ui_customtemplates_base.h"
#include "kpimtextedit/plaintexteditor.h"
#include "templateparseremailaddressrequesterinterfacewidget.h"

#include <KLocalizedString>
#include <KMessageBox>
#include <QIcon>

#include <QWhatsThis>

using namespace TemplateParser;

CustomTemplates::CustomTemplates(const QList<KActionCollection *> &actionCollection, QWidget *parent)
    : QWidget(parent)
    , mBlockChangeSignal(false)
{
    mUi = new Ui_CustomTemplatesBase;
    mUi->setupUi(this);

    mUi->mAdd->setIcon(QIcon::fromTheme(QStringLiteral("list-add")));
    mUi->mAdd->setEnabled(false);
    mUi->mRemove->setIcon(QIcon::fromTheme(QStringLiteral("list-remove")));
    mUi->mDuplicate->setIcon(QIcon::fromTheme(QStringLiteral("edit-copy")));

    mUi->mList->setColumnWidth(0, 100);
    mUi->mList->header()->setStretchLastSection(true);
    mUi->mList->setItemDelegate(new CustomTemplateItemDelegate(this));
    mUi->mList->header()->setSectionsMovable(false);
    mUi->mEditFrame->setEnabled(false);

    mUi->mName->setTrapReturnKey(true);
    connect(mUi->mEdit->editor(), &QPlainTextEdit::textChanged,
            this, &CustomTemplates::slotTextChanged);
    connect(mUi->mToEdit, &TemplateParser::TemplateParserEmailAddressRequesterInterfaceWidget::textChanged, this, &CustomTemplates::slotTextChanged);
    connect(mUi->mCCEdit, &TemplateParser::TemplateParserEmailAddressRequesterInterfaceWidget::textChanged, this, &CustomTemplates::slotTextChanged);

    connect(mUi->mName, &KLineEdit::textChanged, this, &CustomTemplates::slotNameChanged);

    connect(mUi->mName, &KLineEdit::returnPressed, this, &CustomTemplates::slotAddClicked);

    connect(mUi->mInsertCommand, qOverload<const QString &, int>(&TemplateParser::TemplatesInsertCommandPushButton::insertCommand), this, &CustomTemplates::slotInsertCommand);

    connect(mUi->mAdd, &QPushButton::clicked, this, &CustomTemplates::slotAddClicked);
    connect(mUi->mRemove, &QPushButton::clicked, this, &CustomTemplates::slotRemoveClicked);
    connect(mUi->mDuplicate, &QPushButton::clicked, this, &CustomTemplates::slotDuplicateClicked);
    connect(mUi->mList, &QTreeWidget::currentItemChanged, this, &CustomTemplates::slotListSelectionChanged);
    connect(mUi->mList, &QTreeWidget::itemChanged, this, &CustomTemplates::slotItemChanged);
    connect(mUi->mType, qOverload<int>(&QComboBox::activated), this, &CustomTemplates::slotTypeActivated);

    connect(mUi->mKeySequenceWidget, &KKeySequenceWidget::keySequenceChanged, this, &CustomTemplates::slotShortcutChanged);

    mUi->mKeySequenceWidget->setCheckActionCollections(actionCollection);

    mReplyPix = QIcon::fromTheme(QStringLiteral("mail-reply-sender"));
    mReplyAllPix = QIcon::fromTheme(QStringLiteral("mail-reply-all"));
    mForwardPix = QIcon::fromTheme(QStringLiteral("mail-forward"));

    mUi->mType->clear();
    mUi->mType->addItem(QPixmap(), i18nc("Message->", "Universal"));
    mUi->mType->addItem(mReplyPix, i18nc("Message->", "Reply"));
    mUi->mType->addItem(mReplyAllPix, i18nc("Message->", "Reply to All"));
    mUi->mType->addItem(mForwardPix, i18nc("Message->", "Forward"));

    mUi->mHelp->setText(i18n("<a href=\"whatsthis\">How does this work?</a>"));
    connect(mUi->mHelp, &QLabel::linkActivated,
            this, &CustomTemplates::slotHelpLinkClicked);
    mUi->mHelp->setContextMenuPolicy(Qt::NoContextMenu);

    slotNameChanged(mUi->mName->text());
}

void CustomTemplates::slotHelpLinkClicked(const QString &)
{
    const QString help
        = i18n("<qt>"
               "<p>Here you can add, edit, and delete custom message "
               "templates to use when you compose a reply or forwarding message. "
               "Create the custom template by typing the name into the input box "
               "and press the '+' button. Also, you can bind a keyboard "
               "combination to the template for faster operations.</p>"
               "<p>Message templates support substitution commands, "
               "by simply typing them or selecting them from the "
               "<i>Insert command</i> menu.</p>"
               "<p>There are four types of custom templates: used to "
               "<i>Reply</i>, <i>Reply to All</i>, <i>Forward</i>, and "
               "<i>Universal</i> which can be used for all kinds of operations. "
               "You cannot bind a keyboard shortcut to <i>Universal</i> templates.</p>"
               "</qt>");

    QWhatsThis::showText(QCursor::pos(), help);
}

CustomTemplates::~CustomTemplates()
{
    disconnect(mUi->mEdit->editor(), &QPlainTextEdit::textChanged,
               this, &CustomTemplates::slotTextChanged);
    disconnect(mUi->mToEdit, &TemplateParser::TemplateParserEmailAddressRequesterInterfaceWidget::textChanged, this, &CustomTemplates::slotTextChanged);
    disconnect(mUi->mCCEdit, &TemplateParser::TemplateParserEmailAddressRequesterInterfaceWidget::textChanged, this, &CustomTemplates::slotTextChanged);
    delete mUi;
    mUi = nullptr;
}

void CustomTemplates::slotNameChanged(const QString &text)
{
    mUi->mAdd->setEnabled(!text.trimmed().isEmpty());
}

QString CustomTemplates::indexToType(int index)
{
    QString typeStr;
    switch (index) {
    case TUniversal:
        typeStr = i18nc("Message->", "Universal");
        break;
    /*  case TNewMessage:
    typeStr = i18n( "New Message" );
    break; */
    case TReply:
        typeStr = i18nc("Message->", "Reply");
        break;
    case TReplyAll:
        typeStr = i18nc("Message->", "Reply to All");
        break;
    case TForward:
        typeStr = i18nc("Message->", "Forward");
        break;
    default:
        typeStr = i18nc("Message->", "Unknown");
        break;
    }
    return typeStr;
}

void CustomTemplates::slotTextChanged()
{
    QTreeWidgetItem *item = mUi->mList->currentItem();
    if (item) {
        CustomTemplateItem *vitem = static_cast<CustomTemplateItem *>(item);
        vitem->setContent(mUi->mEdit->toPlainText());
        if (!mBlockChangeSignal) {
            vitem->setTo(mUi->mToEdit->text());
            vitem->setCc(mUi->mCCEdit->text());
        }
    }

    if (!mBlockChangeSignal) {
        Q_EMIT changed();
    }
}

void CustomTemplates::iconFromType(CustomTemplates::Type type, CustomTemplateItem *item)
{
    switch (type) {
    case TReply:
        item->setIcon(0, mReplyPix);
        break;
    case TReplyAll:
        item->setIcon(0, mReplyAllPix);
        break;
    case TForward:
        item->setIcon(0, mForwardPix);
        break;
    default:
        item->setIcon(0, QPixmap());
        break;
    }
}

void CustomTemplates::load()
{
    const QStringList list = TemplateParserSettings::self()->customTemplates();
    mUi->mList->clear();
    QStringList::const_iterator end(list.constEnd());
    for (QStringList::const_iterator it = list.constBegin(); it != end; ++it) {
        CTemplates t(*it);
        QKeySequence shortcut(t.shortcut());
        CustomTemplates::Type type = static_cast<Type>(t.type());
        CustomTemplateItem *item = new CustomTemplateItem(mUi->mList, *it, t.content(),
                                                          shortcut, type, t.to(), t.cC());
        item->setText(1, *it);
        item->setText(0, indexToType(type));
        iconFromType(type, item);
    }
    const bool enabled = mUi->mList->topLevelItemCount() > 0 && mUi->mList->currentItem();
    mUi->mRemove->setEnabled(enabled);
    mUi->mDuplicate->setEnabled(enabled);
}

void CustomTemplates::save()
{
    // Before saving the new templates, delete the old ones. That needs to be done before
    // saving, since otherwise a new template with the new name wouldn't get saved.
    KSharedConfig::Ptr config = KSharedConfig::openConfig(QStringLiteral("customtemplatesrc"), KConfig::NoGlobals);
    for (const QString &item : qAsConst(mItemsToDelete)) {
        CTemplates t(item);
        const QString configGroup = t.currentGroup();
        config->deleteGroup(configGroup);
    }

    QStringList list;
    QTreeWidgetItemIterator lit(mUi->mList);
    while (*lit) {
        CustomTemplateItem *it = static_cast<CustomTemplateItem *>(*lit);
        const QString name = it->text(1);
        list.append(name);

        CTemplates t(name);
        QString content = it->content();
        if (content.trimmed().isEmpty()) {
            content = QStringLiteral("%BLANK");
        }

        t.setContent(content);
        t.setShortcut(it->shortcut().toString());
        t.setType(it->customType());
        t.setTo(it->to());
        t.setCC(it->cc());
        t.save();
        ++lit;
    }

    TemplateParserSettings::self()->setCustomTemplates(list);
    TemplateParserSettings::self()->save();

    Q_EMIT templatesUpdated();
}

void CustomTemplates::slotInsertCommand(const QString &cmd, int adjustCursor)
{
    QTextCursor cursor = mUi->mEdit->editor()->textCursor();
    cursor.insertText(cmd);
    cursor.setPosition(cursor.position() + adjustCursor);
    mUi->mEdit->editor()->setTextCursor(cursor);
    mUi->mEdit->editor()->setFocus();
}

bool CustomTemplates::nameAlreadyExists(const QString &str, QTreeWidgetItem *item)
{
    QTreeWidgetItemIterator lit(mUi->mList);
    while (*lit) {
        const QString name = (*lit)->text(1);
        if ((name == str) && ((*lit) != item)) {
            KMessageBox::error(
                this,
                i18n("A template with same name already exists."),
                i18n("Cannot create template"));
            return true;
        }
        ++lit;
    }
    return false;
}

void CustomTemplates::slotAddClicked()
{
    const QString str = mUi->mName->text();
    if (!str.isEmpty()) {
        if (nameAlreadyExists(str)) {
            return;
        }

        QKeySequence nullShortcut;
        CustomTemplateItem *item
            = new CustomTemplateItem(mUi->mList, str, QString(), nullShortcut, TUniversal,
                                     QString(), QString());
        item->setText(0, indexToType(TUniversal));
        item->setText(1, str);
        mUi->mList->setCurrentItem(item);
        mUi->mRemove->setEnabled(true);
        mUi->mDuplicate->setEnabled(true);
        mUi->mName->clear();
        mUi->mKeySequenceWidget->setEnabled(false);
        if (!mBlockChangeSignal) {
            Q_EMIT changed();
        }
    }
}

QString CustomTemplates::createUniqueName(const QString &name) const
{
    QString uniqueName = name;

    int counter = 0;
    bool found = true;

    while (found) {
        found = false;

        QTreeWidgetItemIterator lit(mUi->mList);
        while (*lit) {
            const QString itemName = (*lit)->text(1);
            if (!itemName.compare(uniqueName)) {
                found = true;
                ++counter;
                uniqueName = name;
                uniqueName += QLatin1String(" (") + QString::number(counter) + QLatin1String(")");
                break;
            }
            lit++;
        }
    }

    return uniqueName;
}

void CustomTemplates::slotDuplicateClicked()
{
    QTreeWidgetItem *currentItem = mUi->mList->currentItem();
    if (!currentItem) {
        return;
    }
    CustomTemplateItem *origItem = static_cast<CustomTemplateItem *>(currentItem);
    const QString templateName = createUniqueName(origItem->text(1));
    QKeySequence nullShortcut;
    CustomTemplates::Type type = origItem->customType();
    CustomTemplateItem *item
        = new CustomTemplateItem(mUi->mList, templateName, origItem->content(), nullShortcut, type,
                                 origItem->to(), origItem->cc());
    item->setText(0, indexToType(type));
    item->setText(1, templateName);
    iconFromType(type, item);

    mUi->mList->setCurrentItem(item);
    mUi->mRemove->setEnabled(true);
    mUi->mDuplicate->setEnabled(true);
    mUi->mName->clear();
    mUi->mKeySequenceWidget->setEnabled(type != TUniversal);

    Q_EMIT changed();
}

void CustomTemplates::slotRemoveClicked()
{
    QTreeWidgetItem *item = mUi->mList->currentItem();
    if (!item) {
        return;
    }

    const QString templateName = item->text(1);

    if (KMessageBox::warningContinueCancel(
            this,
            i18nc("@info", "Do you really want to remove template \"%1\"?", templateName),
            i18nc("@title:window", "Remove Template?"),
            KStandardGuiItem::remove(),
            KStandardGuiItem::cancel()) == KMessageBox::Continue) {
        mItemsToDelete.append(templateName);
        delete mUi->mList->takeTopLevelItem(mUi->mList->indexOfTopLevelItem(item));
        mUi->mRemove->setEnabled(mUi->mList->topLevelItemCount() > 0);
        mUi->mDuplicate->setEnabled(mUi->mList->topLevelItemCount() > 0);
        if (!mBlockChangeSignal) {
            Q_EMIT changed();
        }
    }
}

void CustomTemplates::slotListSelectionChanged()
{
    QTreeWidgetItem *item = mUi->mList->currentItem();
    if (item) {
        mUi->mEditFrame->setEnabled(true);
        mUi->mRemove->setEnabled(true);
        mUi->mDuplicate->setEnabled(true);
        CustomTemplateItem *vitem = static_cast<CustomTemplateItem *>(item);
        mBlockChangeSignal = true;
        mUi->mEdit->setPlainText(vitem->content());
        mUi->mKeySequenceWidget->setKeySequence(vitem->shortcut(),
                                                KKeySequenceWidget::NoValidate);
        CustomTemplates::Type type = vitem->customType();

        mUi->mType->setCurrentIndex(mUi->mType->findText(indexToType(type)));
        mUi->mToEdit->setText(vitem->to());
        mUi->mCCEdit->setText(vitem->cc());
        mBlockChangeSignal = false;

        // I think the logic (originally 'vitem->mType==TUniversal') was inverted here:
        // a key shortcut is only allowed for a specific type of template and not for
        // a universal, as otherwise we won't know what sort of action to do when the
        // key sequence is activated!
        // This agrees with KMMainWidget::updateCustomTemplateMenus() -- marten
        mUi->mKeySequenceWidget->setEnabled(type != TUniversal);
    } else {
        mUi->mEditFrame->setEnabled(false);
        mUi->mEdit->editor()->clear();
        // see above
        mUi->mKeySequenceWidget->clearKeySequence();
        mUi->mType->setCurrentIndex(0);
        mUi->mToEdit->clear();
        mUi->mCCEdit->clear();
    }
}

void CustomTemplates::slotTypeActivated(int index)
{
    QTreeWidgetItem *item = mUi->mList->currentItem();
    if (item) {
        CustomTemplateItem *vitem = static_cast<CustomTemplateItem *>(item);
        CustomTemplates::Type customtype = static_cast<Type>(index);
        vitem->setCustomType(customtype);
        vitem->setText(0, indexToType(customtype));

        iconFromType(customtype, vitem);

        // see slotListSelectionChanged() above
        mUi->mKeySequenceWidget->setEnabled(customtype != TUniversal);

        if (!mBlockChangeSignal) {
            Q_EMIT changed();
        }
    }
}

void CustomTemplates::slotShortcutChanged(const QKeySequence &newSeq)
{
    QTreeWidgetItem *item = mUi->mList->currentItem();
    if (item) {
        CustomTemplateItem *vitem = static_cast<CustomTemplateItem *>(item);
        vitem->setShortcut(newSeq);
        mUi->mKeySequenceWidget->applyStealShortcut();
    }

    if (!mBlockChangeSignal) {
        Q_EMIT changed();
    }
}

void CustomTemplates::slotItemChanged(QTreeWidgetItem *item, int column)
{
    if (item) {
        CustomTemplateItem *vitem = static_cast<CustomTemplateItem *>(item);
        if (column == 1) {
            const QString newName = vitem->text(1).trimmed();
            if (!newName.isEmpty()) {
                const QString oldName = vitem->oldName();
                if (nameAlreadyExists(newName, item)) {
                    vitem->setText(1, oldName);
                    return;
                }
                if (newName != oldName) {
                    mItemsToDelete.append(oldName);
                    vitem->setOldName(newName);
                    if (!mBlockChangeSignal) {
                        Q_EMIT changed();
                    }
                }
            }
        }
    }
}

CustomTemplateItemDelegate::CustomTemplateItemDelegate(QObject *parent)
    : QStyledItemDelegate(parent)
{
}

CustomTemplateItemDelegate::~CustomTemplateItemDelegate()
{
}

void CustomTemplateItemDelegate::setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const
{
    KLineEdit *lineEdit = static_cast<KLineEdit *>(editor);
    const QString text = lineEdit->text();
    if (!text.isEmpty()) {
        model->setData(index, text, Qt::EditRole);
    }
}

QWidget *CustomTemplateItemDelegate::createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const
{
    if (index.column() == 1) {
        return QStyledItemDelegate::createEditor(parent, option, index);
    }
    return nullptr;
}

CustomTemplateItem::CustomTemplateItem(QTreeWidget *parent, const QString &name, const QString &content, const QKeySequence &shortcut, CustomTemplates::Type type, const QString &to, const QString &cc)
    : QTreeWidgetItem(parent)
    , mName(name)
    , mContent(content)
    , mShortcut(shortcut)
    , mType(type)
    , mTo(to)
    , mCC(cc)
{
    setFlags(flags() | Qt::ItemIsEditable);
}

CustomTemplateItem::~CustomTemplateItem()
{
}

void CustomTemplateItem::setCustomType(CustomTemplates::Type type)
{
    mType = type;
}

CustomTemplates::Type CustomTemplateItem::customType() const
{
    return mType;
}

QString CustomTemplateItem::to() const
{
    return mTo;
}

QString CustomTemplateItem::cc() const
{
    return mCC;
}

QString CustomTemplateItem::content() const
{
    return mContent;
}

void CustomTemplateItem::setContent(const QString &content)
{
    mContent = content;
}

void CustomTemplateItem::setTo(const QString &to)
{
    mTo = to;
}

void CustomTemplateItem::setCc(const QString &cc)
{
    mCC = cc;
}

QKeySequence CustomTemplateItem::shortcut() const
{
    return mShortcut;
}

void CustomTemplateItem::setShortcut(const QKeySequence &shortcut)
{
    mShortcut = shortcut;
}

QString CustomTemplateItem::oldName() const
{
    return mName;
}

void CustomTemplateItem::setOldName(const QString &name)
{
    mName = name;
}
