/*
  Copyright (c) 2000, 2001, 2002 Cornelius Schumacher <schumacher@kde.org>
  Copyright (C) 2003-2004 Reinhold Kainhofer <reinhold@kainhofer.com>
  Copyright (c) 2005 Rafal Rzepecki <divide@users.sourceforge.net>
  Copyright (c) 2012 Allen Winter <winter@kde.org>

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Library General Public
  License as published by the Free Software Foundation; either
  version 2 of the License, or (at your option) any later version.

  This library 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
  Library General Public License for more details.

  You should have received a copy of the GNU Library General Public License
  along with this library; see the file COPYING.LIB.  If not, write to
  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  Boston, MA 02110-1301, USA.
*/

#include "categoryeditdialog.h"

#include "ui_categoryeditdialog_base.h"

#include <CalendarSupport/CategoryHierarchyReader>
#include <CalendarSupport/CategoryConfig>

#include <KLocalizedString>
#include <QIcon>

#include <QHeaderView>
#include <QList>
#include <QStringList>
#include <QDialogButtonBox>
#include <QPushButton>
#include <QVBoxLayout>

using namespace IncidenceEditorNG;
using namespace CalendarSupport;

CategoryEditDialog::CategoryEditDialog(CategoryConfig *categoryConfig, QWidget *parent)
    : QDialog(parent)
    , mCategoryConfig(categoryConfig)
{
    setWindowTitle(i18n("Edit Categories"));
    QVBoxLayout *mainLayout = new QVBoxLayout(this);
    QDialogButtonBox *buttonBox = new QDialogButtonBox(
        QDialogButtonBox::Ok | QDialogButtonBox::Cancel | QDialogButtonBox::Help, this);
    QPushButton *okButton = buttonBox->button(QDialogButtonBox::Ok);
    okButton->setDefault(true);
    okButton->setShortcut(Qt::CTRL | Qt::Key_Return);
    connect(buttonBox, &QDialogButtonBox::accepted, this, &CategoryEditDialog::accept);
    connect(buttonBox, &QDialogButtonBox::rejected, this, &CategoryEditDialog::reject);
    mWidgets = new Ui::CategoryEditDialog_base();
    QWidget *widget = new QWidget(this);
    widget->setObjectName(QStringLiteral("CategoryEdit"));
    mWidgets->setupUi(widget);

    mWidgets->mCategories->header()->hide();
    mWidgets->mButtonAdd->setIcon(QIcon::fromTheme(QStringLiteral("list-add")));

    mWidgets->mButtonAddSubcategory->setEnabled(false);
    mWidgets->mButtonAddSubcategory->setIcon(QIcon::fromTheme(QStringLiteral("list-add")));

    mWidgets->mButtonRemove->setEnabled(false);
    mWidgets->mButtonRemove->setIcon(QIcon::fromTheme(QStringLiteral("list-remove")));

    mWidgets->mCategories->setDragDropMode(QAbstractItemView::InternalMove);

    // unfortunately, kde-core-devel will not allow this code in QDialog
    // because these button's functionality cannot be easily generalized.
    okButton->setToolTip(i18n("Apply changes and close"));
    okButton->setWhatsThis(i18n("When clicking <b>Ok</b>, "
                                "the settings will be handed over to the "
                                "program and the dialog will be closed."));
    buttonBox->button(QDialogButtonBox::Cancel)->setToolTip(i18n("Cancel changes and close"));
    buttonBox->button(QDialogButtonBox::Cancel)->setWhatsThis(i18n("When clicking <b>Cancel</b>, "
                                                                   "the settings will be discarded and the "
                                                                   "dialog will be closed."));

    buttonBox->button(QDialogButtonBox::Help)->setWhatsThis(i18n("When clicking <b>Help</b>, "
                                                                 "a separate KHelpCenter window will open "
                                                                 "providing more information about the settings."));

    mainLayout->addWidget(widget);
    mainLayout->addWidget(buttonBox);

    fillList();

    mWidgets->mCategories->setFocus();

    connect(mWidgets->mCategories, &IncidenceEditorNG::AutoCheckTreeWidget::itemSelectionChanged,
            this, &CategoryEditDialog::editItem);
    connect(mWidgets->mCategories, &IncidenceEditorNG::AutoCheckTreeWidget::itemSelectionChanged,
            this, &CategoryEditDialog::slotSelectionChanged);
    connect(mWidgets->mCategories, &IncidenceEditorNG::AutoCheckTreeWidget::itemCollapsed, this,
            &CategoryEditDialog::expandIfToplevel);
    connect(mWidgets->mEdit, &QLineEdit::textChanged, this, &CategoryEditDialog::slotTextChanged);
    connect(mWidgets->mButtonAdd, &QPushButton::clicked, this, &CategoryEditDialog::add);
    connect(mWidgets->mButtonAddSubcategory, &QPushButton::clicked, this,
            &CategoryEditDialog::addSubcategory);
    connect(mWidgets->mButtonRemove, &QPushButton::clicked, this, &CategoryEditDialog::remove);
    connect(okButton, &QPushButton::clicked, this, &CategoryEditDialog::slotOk);
    connect(buttonBox->button(
                QDialogButtonBox::Cancel), &QPushButton::clicked, this,
            &CategoryEditDialog::slotCancel);
}

CategoryEditDialog::~CategoryEditDialog()
{
    delete mWidgets;
}

void CategoryEditDialog::fillList()
{
    CalendarSupport::CategoryHierarchyReaderQTreeWidget(
        mWidgets->mCategories).read(mCategoryConfig->customCategories());
}

void CategoryEditDialog::slotTextChanged(const QString &text)
{
    QTreeWidgetItem *item = mWidgets->mCategories->currentItem();
    if (item) {
        item->setText(0, text);
    }
}

void CategoryEditDialog::slotSelectionChanged()
{
    bool enable = (mWidgets->mCategories->selectedItems().count() > 0);
    mWidgets->mButtonAddSubcategory->setEnabled(enable);
    mWidgets->mButtonRemove->setEnabled(enable);
}

void CategoryEditDialog::add()
{
    QTreeWidgetItem *newItem
        = new QTreeWidgetItem(mWidgets->mCategories,
                              QStringList(i18n("New category")));
    newItem->setExpanded(true);

    mWidgets->mCategories->setCurrentItem(newItem);
    mWidgets->mCategories->clearSelection();
    newItem->setSelected(true);
    mWidgets->mCategories->scrollToItem(newItem);
    mWidgets->mEdit->setFocus();
    mWidgets->mEdit->selectAll();
}

void CategoryEditDialog::addSubcategory()
{
    if (!mWidgets->mEdit->text().isEmpty()) {
        QTreeWidgetItem *newItem
            = new QTreeWidgetItem(mWidgets->mCategories->currentItem(),
                                  QStringList(i18n("New subcategory")));
        newItem->setExpanded(true);

        mWidgets->mCategories->setCurrentItem(newItem);
        mWidgets->mCategories->clearSelection();
        newItem->setSelected(true);
        mWidgets->mCategories->scrollToItem(newItem);
        mWidgets->mEdit->setFocus();
        mWidgets->mEdit->selectAll();
    }
}

void CategoryEditDialog::remove()
{
    QList<QTreeWidgetItem *> to_remove = mWidgets->mCategories->selectedItems();
    while (!to_remove.isEmpty()) {
        deleteItem(to_remove.takeFirst(), to_remove);
    }

    if (mWidgets->mCategories->currentItem()) {
        mWidgets->mCategories->currentItem()->setSelected(true);
    }
}

void CategoryEditDialog::deleteItem(QTreeWidgetItem *item, QList<QTreeWidgetItem *> &to_remove)
{
    if (!item) {
        return;
    }

    for (int i = item->childCount() - 1; i >= 0; i--) {
        QTreeWidgetItem *child = item->child(i);
        to_remove.removeAll(child);
        deleteItem(child, to_remove);
    }
    delete item;
}

void CategoryEditDialog::slotOk()
{
    slotApply();
    accept();
}

void CategoryEditDialog::slotApply()
{
    QStringList l;

    QStringList path;
    QTreeWidgetItemIterator it(mWidgets->mCategories);
    while (*it) {
        path = mWidgets->mCategories->pathByItem(*it++);
        path.replaceInStrings(
            CategoryConfig::categorySeparator,
            QLatin1Char('\\') + CategoryConfig::categorySeparator);
        l.append(path.join(CategoryConfig::categorySeparator));
    }
    mCategoryConfig->setCustomCategories(l);
    mCategoryConfig->writeConfig();

    Q_EMIT categoryConfigChanged();
}

void CategoryEditDialog::slotCancel()
{
    reload();
}

void CategoryEditDialog::editItem()
{
    QList<QTreeWidgetItem *> to_edit = mWidgets->mCategories->selectedItems();
    if (!to_edit.isEmpty()) {
        QTreeWidgetItem *item = to_edit.first();
        if (item) {
            mWidgets->mEdit->setText(item->text(0));
        }
    }
}

void CategoryEditDialog::reload()
{
    fillList();
}

void CategoryEditDialog::show()
{
    /*
      QTreeWidgetItem *first = 0;
      if ( mWidgets->mCategories->topLevelItemCount() ) {
        first = mWidgets->mCategories->topLevelItem( 0 );
        mWidgets->mCategories->setCurrentItem( first );
      }
      mWidgets->mCategories->clearSelection();
      if ( first ) {
        first->setSelected( true );
        editItem( first );
      }
    */
    QDialog::show();
}

void CategoryEditDialog::expandIfToplevel(QTreeWidgetItem *item)
{
    if (!item->parent()) {
        item->setExpanded(true);
    }
}
