/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2013-2017 CERN
 * @author Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
 * @author Maciej Suminski <maciej.suminski@cern.ch>
 *
 * 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, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#include <tool/tool_event.h>
#include <tool/tool_manager.h>
#include <tool/tool_interactive.h>
#include <tool/context_menu.h>
#include <wx/log.h>
#include <pgm_base.h>

#include <functional>
using namespace std::placeholders;

CONTEXT_MENU::CONTEXT_MENU() :
    m_titleDisplayed( false ), m_selected( -1 ), m_tool( nullptr ), m_icon( nullptr )
{
    setupEvents();
}


CONTEXT_MENU::~CONTEXT_MENU()
{
    // Set parent to NULL to prevent submenus from unregistering from a notexisting object
    for( auto menu : m_submenus )
        menu->SetParent( nullptr );

    CONTEXT_MENU* parent = dynamic_cast<CONTEXT_MENU*>( GetParent() );
    wxASSERT( parent || !GetParent() );

    if( parent )
        parent->m_submenus.remove( this );
}

/*
 * Helper function.
 * Assigns an icon to the wxMenuItem aMenu.
 * aIcon is the icon to be assigned can be NULL.
 */
static void set_wxMenuIcon( wxMenuItem* aMenu, const BITMAP_OPAQUE* aIcon )
{
    // Retrieve the global applicaton show icon option:
    bool useImagesInMenus;
    Pgm().CommonSettings()->Read( USE_ICONS_IN_MENUS_KEY, &useImagesInMenus );

    if( aIcon && useImagesInMenus )
        aMenu->SetBitmap( KiBitmap( aIcon ) );
}


void CONTEXT_MENU::SetIcon( const BITMAP_OPAQUE* aIcon )
{
    m_icon = aIcon;
}


void CONTEXT_MENU::setupEvents()
{
    Connect( wxEVT_MENU_HIGHLIGHT, wxMenuEventHandler( CONTEXT_MENU::onMenuEvent ), NULL, this );
    Connect( wxEVT_COMMAND_MENU_SELECTED, wxMenuEventHandler( CONTEXT_MENU::onMenuEvent ), NULL, this );
}


void CONTEXT_MENU::SetTitle( const wxString& aTitle )
{
    // Unfortunately wxMenu::SetTitle() does not work very well, so this is an alternative version
    m_title = aTitle;

    // Update the menu title
    if( m_titleDisplayed )
        DisplayTitle( true );
}


void CONTEXT_MENU::DisplayTitle( bool aDisplay )
{
    if( ( !aDisplay || m_title.IsEmpty() ) && m_titleDisplayed )
    {
        // Destroy the menu entry keeping the title..
        wxMenuItem* item = FindItemByPosition( 0 );
        wxASSERT( item->GetItemLabelText() == GetTitle() );
        Destroy( item );
        // ..and separator
        item = FindItemByPosition( 0 );
        wxASSERT( item->IsSeparator() );
        Destroy( item );
        m_titleDisplayed = false;
    }

    else if( aDisplay && !m_title.IsEmpty() )
    {
        if( m_titleDisplayed )
        {
            // Simply update the title
            FindItemByPosition( 0 )->SetItemLabel( m_title );
        }
        else
        {
            // Add a separator and a menu entry to display the title
            InsertSeparator( 0 );
            Insert( 0, new wxMenuItem( this, wxID_NONE, m_title, wxEmptyString, wxITEM_NORMAL ) );

            if( m_icon )
                set_wxMenuIcon( FindItemByPosition( 0 ), m_icon );

            m_titleDisplayed = true;
        }
    }
}


wxMenuItem* CONTEXT_MENU::Add( const wxString& aLabel, int aId, const BITMAP_OPAQUE* aIcon )
{
#ifdef DEBUG
    if( FindItem( aId ) != NULL )
        wxLogWarning( wxT( "Adding more than one menu entry with the same ID may result in"
                "undefined behaviour" ) );
#endif

    wxMenuItem* item = new wxMenuItem( this, aId, aLabel, wxEmptyString, wxITEM_NORMAL );
    set_wxMenuIcon( item, aIcon );

    return Append( item );
}


wxMenuItem* CONTEXT_MENU::Add( const TOOL_ACTION& aAction )
{
    /// ID numbers for tool actions need to have a value higher than ACTION_ID
    const BITMAP_OPAQUE* icon = aAction.GetIcon();

    wxMenuItem* item = new wxMenuItem( this, getMenuId( aAction ), aAction.GetMenuItem(),
                                       aAction.GetDescription(), wxITEM_NORMAL );

    set_wxMenuIcon( item, icon );

    m_toolActions[getMenuId( aAction )] = &aAction;

    wxMenuItem* i = Append( item );
    return i;
}


std::list<wxMenuItem*> CONTEXT_MENU::Add( CONTEXT_MENU* aMenu, bool aExpand )
{
    std::list<wxMenuItem*> items;
    CONTEXT_MENU* menuCopy = aMenu->Clone();
    m_submenus.push_back( menuCopy );

    if( aExpand )
    {
        for( int i = 0; i < (int) aMenu->GetMenuItemCount(); ++i )
        {
            wxMenuItem* item = aMenu->FindItemByPosition( i );
            items.push_back( appendCopy( item ) );
        }
    }
    else
    {
        wxASSERT_MSG( !menuCopy->m_title.IsEmpty(), "Set a title for CONTEXT_MENU using SetTitle()" );

        if( aMenu->m_icon )
        {
            wxMenuItem* newItem = new wxMenuItem( this, -1, menuCopy->m_title );
            set_wxMenuIcon( newItem, aMenu->m_icon );
            newItem->SetSubMenu( menuCopy );
            items.push_back( Append( newItem ) );
        }
        else
        {
            items.push_back( AppendSubMenu( menuCopy, menuCopy->m_title ) );
        }
    }

    return items;
}


void CONTEXT_MENU::Clear()
{
    m_titleDisplayed = false;

    for( int i = GetMenuItemCount() - 1; i >= 0; --i )
        Destroy( FindItemByPosition( i ) );

    m_toolActions.clear();
    m_submenus.clear();

    wxASSERT( GetMenuItemCount() == 0 );
}


bool CONTEXT_MENU::HasEnabledItems() const
{
    bool hasEnabled = false;

    auto& items = GetMenuItems();

    for( auto item : items )
    {
        if( item->IsEnabled() && !item->IsSeparator() )
        {
            hasEnabled = true;
            break;
        }
    }

    return hasEnabled;
}


void CONTEXT_MENU::UpdateAll()
{
    try
    {
        update();
    }
    catch( std::exception& e )
    {
        wxLogDebug( wxString::Format( "CONTEXT_MENU update handler exception: %s", e.what() ) );
    }

    if( m_tool )
        updateHotKeys();

    runOnSubmenus( std::bind( &CONTEXT_MENU::UpdateAll, _1 ) );
}


void CONTEXT_MENU::SetTool( TOOL_INTERACTIVE* aTool )
{
    m_tool = aTool;
    runOnSubmenus( std::bind( &CONTEXT_MENU::SetTool, _1, aTool ) );
}


CONTEXT_MENU* CONTEXT_MENU::Clone() const
{
    CONTEXT_MENU* clone = create();
    clone->Clear();
    clone->copyFrom( *this );
    return clone;
}


CONTEXT_MENU* CONTEXT_MENU::create() const
{
    CONTEXT_MENU* menu = new CONTEXT_MENU();

    wxASSERT_MSG( typeid( *this ) == typeid( *menu ),
            wxString::Format( "You need to override create() method for class %s", typeid(*this).name() ) );

    return menu;
}


TOOL_MANAGER* CONTEXT_MENU::getToolManager() const
{
    wxASSERT( m_tool );
    return m_tool ? m_tool->GetManager() : nullptr;
}


void CONTEXT_MENU::updateHotKeys()
{
    TOOL_MANAGER* toolMgr = getToolManager();

    for( std::map<int, const TOOL_ACTION*>::const_iterator it = m_toolActions.begin();
            it != m_toolActions.end(); ++it )
    {
        int id = it->first;
        const TOOL_ACTION& action = *it->second;
        int key = toolMgr->GetHotKey( action ) & ~MD_MODIFIER_MASK;

        if( key )
        {
            int mod = toolMgr->GetHotKey( action ) & MD_MODIFIER_MASK;
            int flags = 0;
            wxMenuItem* item = FindChildItem( id );

            if( item )
            {
                flags |= ( mod & MD_ALT ) ? wxACCEL_ALT : 0;
                flags |= ( mod & MD_CTRL ) ? wxACCEL_CTRL : 0;
                flags |= ( mod & MD_SHIFT ) ? wxACCEL_SHIFT : 0;

                if( !flags )
                    flags = wxACCEL_NORMAL;

                wxAcceleratorEntry accel( flags, key, id, item );
                item->SetAccel( &accel );
            }
        }
    }
}


void CONTEXT_MENU::onMenuEvent( wxMenuEvent& aEvent )
{
    OPT_TOOL_EVENT evt;

    wxEventType type = aEvent.GetEventType();

    // When the currently chosen item in the menu is changed, an update event is issued.
    // For example, the selection tool can use this to dynamically highlight the current item
    // from selection clarification popup.
    if( type == wxEVT_MENU_HIGHLIGHT )
        evt = TOOL_EVENT( TC_COMMAND, TA_CONTEXT_MENU_UPDATE, aEvent.GetId() );

    // One of menu entries was selected..
    else if( type == wxEVT_COMMAND_MENU_SELECTED )
    {
        // Store the selected position, so it can be checked by the tools
        m_selected = aEvent.GetId();

        CONTEXT_MENU* parent = dynamic_cast<CONTEXT_MENU*>( GetParent() );

        while( parent )
        {
            parent->m_selected = m_selected;
            parent = dynamic_cast<CONTEXT_MENU*>( parent->GetParent() );
        }

        // Check if there is a TOOL_ACTION for the given ID
        if( m_selected >= ACTION_ID )
            evt = findToolAction( m_selected );

        if( !evt )
        {
#ifdef __WINDOWS__
            if( !evt )
            {
                // Try to find the submenu which holds the selected item
                wxMenu* menu = nullptr;
                FindItem( m_selected, &menu );

                if( menu && menu != this )
                {
                    CONTEXT_MENU* cxmenu = static_cast<CONTEXT_MENU*>( menu );
                    evt = cxmenu->eventHandler( aEvent );
                }
            }
#else
            if( !evt )
                runEventHandlers( aEvent, evt );
#endif

            // Handling non-action menu entries (e.g. items in clarification list)
            if( !evt )
                evt = TOOL_EVENT( TC_COMMAND, TA_CONTEXT_MENU_CHOICE, aEvent.GetId() );
        }
    }

    wxASSERT( m_tool );   // without tool & tool manager we cannot handle events

    // forward the action/update event to the TOOL_MANAGER
    if( evt && m_tool )
    {
        //aEvent.StopPropagation();
        m_tool->GetManager()->ProcessEvent( *evt );
    }
}


void CONTEXT_MENU::runEventHandlers( const wxMenuEvent& aMenuEvent, OPT_TOOL_EVENT& aToolEvent )
{
    aToolEvent = eventHandler( aMenuEvent );

    if( !aToolEvent )
        runOnSubmenus( std::bind( &CONTEXT_MENU::runEventHandlers, _1, aMenuEvent, aToolEvent ) );
}


void CONTEXT_MENU::runOnSubmenus( std::function<void(CONTEXT_MENU*)> aFunction )
{
    try
    {
        std::for_each( m_submenus.begin(), m_submenus.end(), [&]( CONTEXT_MENU* m ) {
            aFunction( m );
            m->runOnSubmenus( aFunction );
        } );
    }
    catch( std::exception& e )
    {
        wxLogDebug( wxString::Format( "CONTEXT_MENU runOnSubmenus exception: %s", e.what() ) );
    }
}


OPT_TOOL_EVENT CONTEXT_MENU::findToolAction( int aId )
{
    OPT_TOOL_EVENT evt;

    auto findFunc = [&]( CONTEXT_MENU* m ) {
        if( evt )
            return;

        const auto it = m->m_toolActions.find( aId );

        if( it != m->m_toolActions.end() )
            evt = it->second->MakeEvent();
    };

    findFunc( this );

    if( !evt )
        runOnSubmenus( findFunc );

    return evt;
}


void CONTEXT_MENU::copyFrom( const CONTEXT_MENU& aMenu )
{
    m_icon = aMenu.m_icon;
    m_title = aMenu.m_title;
    m_titleDisplayed = aMenu.m_titleDisplayed;
    m_selected = -1; // aMenu.m_selected;
    m_tool = aMenu.m_tool;
    m_toolActions = aMenu.m_toolActions;

    // Copy all menu entries
    for( int i = 0; i < (int) aMenu.GetMenuItemCount(); ++i )
    {
        wxMenuItem* item = aMenu.FindItemByPosition( i );
        appendCopy( item );
    }
}


wxMenuItem* CONTEXT_MENU::appendCopy( const wxMenuItem* aSource )
{
    wxMenuItem* newItem = new wxMenuItem( this, aSource->GetId(), aSource->GetItemLabel(),
                                          aSource->GetHelp(), aSource->GetKind() );

    bool useImagesInMenus;
    Pgm().CommonSettings()->Read( USE_ICONS_IN_MENUS_KEY, &useImagesInMenus );

    if( aSource->GetKind() == wxITEM_NORMAL && useImagesInMenus )
        newItem->SetBitmap( aSource->GetBitmap() );

    if( aSource->IsSubMenu() )
    {
        CONTEXT_MENU* menu = dynamic_cast<CONTEXT_MENU*>( aSource->GetSubMenu() );
        wxASSERT_MSG( menu, "Submenus are expected to be a CONTEXT_MENU" );

        if( menu )
        {
            CONTEXT_MENU* menuCopy = menu->Clone();
            newItem->SetSubMenu( menuCopy );
            m_submenus.push_back( menuCopy );
        }
    }

    // wxMenuItem has to be added before enabling/disabling or checking
    Append( newItem );

    if( aSource->IsCheckable() )
        newItem->Check( aSource->IsChecked() );

    newItem->Enable( aSource->IsEnabled() );

    return newItem;
}