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** Copyright (C) 2016 The Qt Company Ltd.
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#include "editortoolbar.h"

#include <coreplugin/actionmanager/actionmanager.h>
#include <coreplugin/actionmanager/command.h>
#include <coreplugin/editormanager/documentmodel.h>
#include <coreplugin/editormanager/editormanager.h>
#include <coreplugin/editormanager/editormanager_p.h>
#include <coreplugin/editormanager/ieditor.h>
#include <coreplugin/fileiconprovider.h>
#include <coreplugin/icore.h>

#include <utils/fileutils.h>
#include <utils/hostosinfo.h>
#include <utils/qtcassert.h>
#include <utils/utilsicons.h>

#include <QApplication>
#include <QComboBox>
#include <QDir>
#include <QDrag>
#include <QLabel>
#include <QMenu>
#include <QMimeData>
#include <QMouseEvent>
#include <QTimer>
#include <QToolButton>
#include <QVBoxLayout>

#include <QDebug>

enum {
    debug = false
};

namespace Core {

struct EditorToolBarPrivate
{
    explicit EditorToolBarPrivate(QWidget *parent, EditorToolBar *q);

    QComboBox *m_editorList;
    QToolButton *m_closeEditorButton;
    QToolButton *m_lockButton;
    QToolButton *m_dragHandle;
    QMenu *m_dragHandleMenu;
    EditorToolBar::MenuProvider m_menuProvider;
    QAction *m_goBackAction;
    QAction *m_goForwardAction;
    QToolButton *m_backButton;
    QToolButton *m_forwardButton;
    QToolButton *m_splitButton;
    QAction *m_horizontalSplitAction;
    QAction *m_verticalSplitAction;
    QAction *m_splitNewWindowAction;
    QToolButton *m_closeSplitButton;

    QWidget *m_activeToolBar;
    QWidget *m_toolBarPlaceholder;
    QWidget *m_defaultToolBar;

    QPoint m_dragStartPosition;

    bool m_isStandalone;
};

EditorToolBarPrivate::EditorToolBarPrivate(QWidget *parent, EditorToolBar *q) :
    m_editorList(new QComboBox(q)),
    m_closeEditorButton(new QToolButton(q)),
    m_lockButton(new QToolButton(q)),
    m_dragHandle(new QToolButton(q)),
    m_dragHandleMenu(nullptr),
    m_goBackAction(new QAction(Utils::Icons::PREV_TOOLBAR.icon(), EditorManager::tr("Go Back"), parent)),
    m_goForwardAction(new QAction(Utils::Icons::NEXT_TOOLBAR.icon(), EditorManager::tr("Go Forward"), parent)),
    m_backButton(new QToolButton(q)),
    m_forwardButton(new QToolButton(q)),
    m_splitButton(new QToolButton(q)),
    m_horizontalSplitAction(new QAction(Utils::Icons::SPLIT_HORIZONTAL.icon(),
                                        EditorManager::tr("Split"), parent)),
    m_verticalSplitAction(new QAction(Utils::Icons::SPLIT_VERTICAL.icon(),
                                      EditorManager::tr("Split Side by Side"), parent)),
    m_splitNewWindowAction(new QAction(EditorManager::tr("Open in New Window"), parent)),
    m_closeSplitButton(new QToolButton(q)),
    m_activeToolBar(nullptr),
    m_toolBarPlaceholder(new QWidget(q)),
    m_defaultToolBar(new QWidget(q)),
    m_isStandalone(false)
{
}

/*!
  Mimic the look of the text editor toolbar as defined in e.g. EditorView::EditorView
  */
EditorToolBar::EditorToolBar(QWidget *parent) :
        Utils::StyledBar(parent), d(new EditorToolBarPrivate(parent, this))
{
    auto toolBarLayout = new QHBoxLayout(this);
    toolBarLayout->setMargin(0);
    toolBarLayout->setSpacing(0);
    toolBarLayout->addWidget(d->m_defaultToolBar);
    d->m_toolBarPlaceholder->setLayout(toolBarLayout);
    d->m_toolBarPlaceholder->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);

    d->m_defaultToolBar->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);
    d->m_activeToolBar = d->m_defaultToolBar;

    d->m_lockButton->setAutoRaise(true);
    d->m_lockButton->setEnabled(false);

    d->m_dragHandle->setProperty("noArrow", true);
    d->m_dragHandle->setToolTip(tr("Drag to drag documents between splits"));
    d->m_dragHandle->installEventFilter(this);
    d->m_dragHandleMenu = new QMenu(d->m_dragHandle);
    d->m_dragHandle->setMenu(d->m_dragHandleMenu);

    connect(d->m_goBackAction, &QAction::triggered, this, &EditorToolBar::goBackClicked);
    connect(d->m_goForwardAction, &QAction::triggered, this, &EditorToolBar::goForwardClicked);

    d->m_editorList->setProperty("hideicon", true);
    d->m_editorList->setProperty("notelideasterisk", true);
    d->m_editorList->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
    d->m_editorList->setMinimumContentsLength(20);
    d->m_editorList->setSizeAdjustPolicy(QComboBox::AdjustToMinimumContentsLengthWithIcon);
    d->m_editorList->setModel(DocumentModel::model());
    d->m_editorList->setMaxVisibleItems(40);
    d->m_editorList->setContextMenuPolicy(Qt::CustomContextMenu);

    d->m_closeEditorButton->setAutoRaise(true);
    d->m_closeEditorButton->setIcon(Utils::Icons::CLOSE_TOOLBAR.icon());
    d->m_closeEditorButton->setEnabled(false);
    d->m_closeEditorButton->setProperty("showborder", true);

    d->m_toolBarPlaceholder->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);

    d->m_backButton->setDefaultAction(d->m_goBackAction);

    d->m_forwardButton->setDefaultAction(d->m_goForwardAction);

    d->m_splitButton->setIcon(Utils::Icons::SPLIT_HORIZONTAL_TOOLBAR.icon());
    d->m_splitButton->setToolTip(tr("Split"));
    d->m_splitButton->setPopupMode(QToolButton::InstantPopup);
    d->m_splitButton->setProperty("noArrow", true);
    auto splitMenu = new QMenu(d->m_splitButton);
    splitMenu->addAction(d->m_horizontalSplitAction);
    splitMenu->addAction(d->m_verticalSplitAction);
    splitMenu->addAction(d->m_splitNewWindowAction);
    d->m_splitButton->setMenu(splitMenu);

    d->m_closeSplitButton->setAutoRaise(true);
    d->m_closeSplitButton->setIcon(Utils::Icons::CLOSE_SPLIT_BOTTOM.icon());

    auto toplayout = new QHBoxLayout(this);
    toplayout->setSpacing(0);
    toplayout->setMargin(0);
    toplayout->addWidget(d->m_backButton);
    toplayout->addWidget(d->m_forwardButton);
    toplayout->addWidget(d->m_lockButton);
    toplayout->addWidget(d->m_dragHandle);
    toplayout->addWidget(d->m_editorList);
    toplayout->addWidget(d->m_closeEditorButton);
    toplayout->addWidget(d->m_toolBarPlaceholder, 1); // Custom toolbar stretches
    toplayout->addWidget(d->m_splitButton);
    toplayout->addWidget(d->m_closeSplitButton);

    setLayout(toplayout);

    // this signal is disconnected for standalone toolbars and replaced with
    // a private slot connection
    connect(d->m_editorList, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated),
            this, &EditorToolBar::listSelectionActivated);

    connect(d->m_editorList, &QComboBox::customContextMenuRequested, [this](QPoint p) {
       QMenu menu;
       fillListContextMenu(&menu);
       menu.exec(d->m_editorList->mapToGlobal(p));
    });
    connect(d->m_dragHandleMenu, &QMenu::aboutToShow, [this]() {
       d->m_dragHandleMenu->clear();
       fillListContextMenu(d->m_dragHandleMenu);
    });
    connect(d->m_lockButton, &QAbstractButton::clicked, this, &EditorToolBar::makeEditorWritable);
    connect(d->m_closeEditorButton, &QAbstractButton::clicked,
            this, &EditorToolBar::closeEditor, Qt::QueuedConnection);
    connect(d->m_horizontalSplitAction, &QAction::triggered,
            this, &EditorToolBar::horizontalSplitClicked, Qt::QueuedConnection);
    connect(d->m_verticalSplitAction, &QAction::triggered,
            this, &EditorToolBar::verticalSplitClicked, Qt::QueuedConnection);
    connect(d->m_splitNewWindowAction, &QAction::triggered,
            this, &EditorToolBar::splitNewWindowClicked, Qt::QueuedConnection);
    connect(d->m_closeSplitButton, &QAbstractButton::clicked,
            this, &EditorToolBar::closeSplitClicked, Qt::QueuedConnection);


    connect(ActionManager::command(Constants::CLOSE), &Command::keySequenceChanged,
            this, &EditorToolBar::updateActionShortcuts);
    connect(ActionManager::command(Constants::GO_BACK), &Command::keySequenceChanged,
            this, &EditorToolBar::updateActionShortcuts);
    connect(ActionManager::command(Constants::GO_FORWARD), &Command::keySequenceChanged,
            this, &EditorToolBar::updateActionShortcuts);

    updateActionShortcuts();
}

EditorToolBar::~EditorToolBar()
{
    delete d;
}

void EditorToolBar::removeToolbarForEditor(IEditor *editor)
{
    QTC_ASSERT(editor, return);
    disconnect(editor->document(), &IDocument::changed, this, &EditorToolBar::checkDocumentStatus);

    QWidget *toolBar = editor->toolBar();
    if (toolBar != nullptr) {
        if (d->m_activeToolBar == toolBar) {
            d->m_activeToolBar = d->m_defaultToolBar;
            d->m_activeToolBar->setVisible(true);
        }
        d->m_toolBarPlaceholder->layout()->removeWidget(toolBar);
        toolBar->setVisible(false);
        toolBar->setParent(nullptr);
    }
}

void EditorToolBar::setCloseSplitEnabled(bool enable)
{
    d->m_closeSplitButton->setVisible(enable);
}

void EditorToolBar::setCloseSplitIcon(const QIcon &icon)
{
    d->m_closeSplitButton->setIcon(icon);
}

void EditorToolBar::closeEditor()
{
    if (d->m_isStandalone)
        EditorManager::slotCloseCurrentEditorOrDocument();
    emit closeClicked();
}

void EditorToolBar::addEditor(IEditor *editor)
{
    QTC_ASSERT(editor, return);
    connect(editor->document(), &IDocument::changed, this, &EditorToolBar::checkDocumentStatus);
    QWidget *toolBar = editor->toolBar();

    if (toolBar && !d->m_isStandalone)
        addCenterToolBar(toolBar);
}

void EditorToolBar::addCenterToolBar(QWidget *toolBar)
{
    QTC_ASSERT(toolBar, return);
    toolBar->setVisible(false); // will be made visible in setCurrentEditor
    d->m_toolBarPlaceholder->layout()->addWidget(toolBar);

    updateToolBar(toolBar);
}

void EditorToolBar::updateToolBar(QWidget *toolBar)
{
    if (!toolBar)
        toolBar = d->m_defaultToolBar;
    if (d->m_activeToolBar == toolBar)
        return;
    toolBar->setVisible(true);
    d->m_activeToolBar->setVisible(false);
    d->m_activeToolBar = toolBar;
}

void EditorToolBar::setToolbarCreationFlags(ToolbarCreationFlags flags)
{
    d->m_isStandalone = flags & FlagsStandalone;
    if (d->m_isStandalone) {
        connect(EditorManager::instance(),
                &EditorManager::currentEditorChanged,
                this,
                &EditorToolBar::setCurrentEditor);

        disconnect(d->m_editorList, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated),
                   this, &EditorToolBar::listSelectionActivated);
        connect(d->m_editorList, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated),
                this, &EditorToolBar::changeActiveEditor);
        d->m_splitButton->setVisible(false);
        d->m_closeSplitButton->setVisible(false);
    }
}

void EditorToolBar::setMenuProvider(const EditorToolBar::MenuProvider &provider)
{
    d->m_menuProvider = provider;
}

void EditorToolBar::setCurrentEditor(IEditor *editor)
{
    IDocument *document = editor ? editor->document() : nullptr;
    const Utils::optional<int> index = DocumentModel::rowOfDocument(document);
    if (QTC_GUARD(index))
        d->m_editorList->setCurrentIndex(*index);

    // If we never added the toolbar from the editor,  we will never change
    // the editor, so there's no need to update the toolbar either.
    if (!d->m_isStandalone)
        updateToolBar(editor ? editor->toolBar() : nullptr);

    updateDocumentStatus(document);
}

void EditorToolBar::changeActiveEditor(int row)
{
    EditorManager::activateEditorForEntry(DocumentModel::entryAtRow(row));
}

void EditorToolBar::fillListContextMenu(QMenu *menu)
{
    if (d->m_menuProvider) {
        d->m_menuProvider(menu);
    } else {
        IEditor *editor = EditorManager::currentEditor();
        DocumentModel::Entry *entry = editor ? DocumentModel::entryForDocument(editor->document())
                                             : nullptr;
        EditorManager::addSaveAndCloseEditorActions(menu, entry, editor);
        menu->addSeparator();
        EditorManager::addNativeDirAndOpenWithActions(menu, entry);
    }
}

void EditorToolBar::makeEditorWritable()
{
    if (IDocument *current = EditorManager::currentDocument())
        Internal::EditorManagerPrivate::makeFileWritable(current);
}

void EditorToolBar::setCanGoBack(bool canGoBack)
{
    d->m_goBackAction->setEnabled(canGoBack);
}

void EditorToolBar::setCanGoForward(bool canGoForward)
{
    d->m_goForwardAction->setEnabled(canGoForward);
}

void EditorToolBar::updateActionShortcuts()
{
    d->m_closeEditorButton->setToolTip(ActionManager::command(Constants::CLOSE)->stringWithAppendedShortcut(EditorManager::tr("Close Document")));
    d->m_goBackAction->setToolTip(ActionManager::command(Constants::GO_BACK)->action()->toolTip());
    d->m_goForwardAction->setToolTip(ActionManager::command(Constants::GO_FORWARD)->action()->toolTip());
    d->m_closeSplitButton->setToolTip(ActionManager::command(Constants::REMOVE_CURRENT_SPLIT)->stringWithAppendedShortcut(tr("Remove Split")));
}

void EditorToolBar::checkDocumentStatus()
{
    auto document = qobject_cast<IDocument *>(sender());
    QTC_ASSERT(document, return);
    DocumentModel::Entry *entry = DocumentModel::entryAtRow(
                d->m_editorList->currentIndex());

    if (entry && entry->document && entry->document == document)
        updateDocumentStatus(document);
}

void EditorToolBar::updateDocumentStatus(IDocument *document)
{
    d->m_closeEditorButton->setEnabled(document != nullptr);

    if (!document) {
        d->m_lockButton->setIcon(QIcon());
        d->m_lockButton->setEnabled(false);
        d->m_lockButton->setToolTip(QString());
        d->m_dragHandle->setIcon(QIcon());
        d->m_editorList->setToolTip(QString());
        return;
    }

    if (document->filePath().isEmpty()) {
        d->m_lockButton->setIcon(QIcon());
        d->m_lockButton->setEnabled(false);
        d->m_lockButton->setToolTip(QString());
    } else if (document->isFileReadOnly()) {
        const static QIcon locked = Utils::Icons::LOCKED_TOOLBAR.icon();
        d->m_lockButton->setIcon(locked);
        d->m_lockButton->setEnabled(true);
        d->m_lockButton->setToolTip(tr("Make Writable"));
    } else {
        const static QIcon unlocked = Utils::Icons::UNLOCKED_TOOLBAR.icon();
        d->m_lockButton->setIcon(unlocked);
        d->m_lockButton->setEnabled(false);
        d->m_lockButton->setToolTip(tr("File is writable"));
    }

    if (document->filePath().isEmpty())
        d->m_dragHandle->setIcon(QIcon());
    else
        d->m_dragHandle->setIcon(FileIconProvider::icon(document->filePath().toFileInfo()));

    d->m_editorList->setToolTip(document->filePath().isEmpty()
                                ? document->displayName()
                                : document->filePath().toUserOutput());
}

bool EditorToolBar::eventFilter(QObject *obj, QEvent *event)
{
    if (obj == d->m_dragHandle) {
        if (event->type() == QEvent::MouseButtonPress) {
            auto me = static_cast<QMouseEvent *>(event);
            if (me->buttons() == Qt::LeftButton)
                d->m_dragStartPosition = me->pos();
            return true; // do not pop up menu already on press
        } else if (event->type() == QEvent::MouseButtonRelease) {
            d->m_dragHandle->showMenu();
            return true;
        } else if (event->type() == QEvent::MouseMove) {
            auto me = static_cast<QMouseEvent *>(event);
            if (me->buttons() != Qt::LeftButton)
                return Utils::StyledBar::eventFilter(obj, event);
            if ((me->pos() - d->m_dragStartPosition).manhattanLength()
                    < QApplication::startDragDistance())
                return Utils::StyledBar::eventFilter(obj, event);
            DocumentModel::Entry *entry = DocumentModel::entryAtRow(
                        d->m_editorList->currentIndex());
            if (!entry) // no document
                return Utils::StyledBar::eventFilter(obj, event);
            auto drag = new QDrag(this);
            auto data = new Utils::DropMimeData;
            data->addFile(entry->fileName().toString());
            drag->setMimeData(data);
            Qt::DropAction action = drag->exec(Qt::MoveAction | Qt::CopyAction, Qt::MoveAction);
            if (action == Qt::MoveAction)
                emit currentDocumentMoved();
            return true;
        }
    }
    return Utils::StyledBar::eventFilter(obj, event);
}

void EditorToolBar::setNavigationVisible(bool isVisible)
{
    d->m_goBackAction->setVisible(isVisible);
    d->m_goForwardAction->setVisible(isVisible);
    d->m_backButton->setVisible(isVisible);
    d->m_forwardButton->setVisible(isVisible);
}

} // Core