/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2013 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
 */

#ifndef __TOOL_MANAGER_H
#define __TOOL_MANAGER_H

#include <typeinfo>
#include <map>
#include <list>
#include <stack>

#include <tool/tool_base.h>
#include <view/view_controls.h>

class TOOLS_HOLDER;
class TOOL_BASE;
class ACTION_MANAGER;
class ACTION_MENU;


/**
 * TOOL_MANAGER.
 * Master controller class:
 * - registers editing tools
 * - pumps UI events to tools requesting them
 * - manages tool state machines (transitions and wait requests)
 */
class TOOL_MANAGER
{
private:
    struct TOOL_STATE;

public:
    TOOL_MANAGER();

    ~TOOL_MANAGER();

    // Helper typedefs
    typedef std::map<TOOL_BASE*, TOOL_STATE*> TOOL_STATE_MAP;
    typedef std::map<std::string, TOOL_STATE*> NAME_STATE_MAP;
    typedef std::map<TOOL_ID, TOOL_STATE*> ID_STATE_MAP;
    typedef std::list<TOOL_ID> ID_LIST;

    /**
     * Generates a unique ID from for a tool with given name.
     */
    static TOOL_ID MakeToolId( const std::string& aToolName );

    /**
     * Function RegisterTool()
     * Adds a tool to the manager set and sets it up. Called once for
     * each tool during application initialization.
     * @param aTool: tool to be added. Ownership is transferred.
     */
    void RegisterTool( TOOL_BASE* aTool );

    /**
     * Function InvokeTool()
     * Calls a tool by sending a tool activation event to tool of given ID.
     *
     * @param aToolId is the ID number of the requested tool.
     * @return True if the requested tool was invoked successfully.
     */
    bool InvokeTool( TOOL_ID aToolId );

    /**
     * Function InvokeTool()
     * Calls a tool by sending a tool activation event to tool of given name.
     *
     * @param aToolName is the name of the requested tool.
     * @return True if the requested tool was invoked successfully.
     */
    bool InvokeTool( const std::string& aToolName );

    /**
     * Shutdown all tools with a currently registered event loop in this tool manager
     * by waking them up with a null event.
     */
    void ShutdownAllTools();

    /**
     * Shutdown the specified tool by waking it up with a null event to terminate
     * the processing loop.
     *
     * @param aTool is the tool to shutdown
     */
    void ShutdownTool( TOOL_BASE* aTool );

    /**
     * Shutdown the specified tool by waking it up with a null event to terminate
     * the processing loop.
     *
     * @param aToolId is the ID of the tool to shutdown
     */
    void ShutdownTool( TOOL_ID aToolId );

    /**
     * Shutdown the specified tool by waking it up with a null event to terminate
     * the processing loop.
     *
     * @param aToolName is name of the tool to shutdown
     */
    void ShutdownTool( const std::string& aToolName );

    /**
     * Function RunAction()
     * Runs the specified action. The common format for action names is "application.ToolName.Action".
     *
     * @param aActionName is the name of action to be invoked.
     * @param aNow decides if the action has to be run immediately or after the current coroutine
     * is preemptied.
     * @param aParam is an optional parameter that might be used by the invoked action. Its meaning
     * depends on the action.
     * @return False if the action was not found.
     */
    template<typename T>
    bool RunAction( const std::string& aActionName, bool aNow = false, T aParam = NULL )
    {
        return RunAction( aActionName, aNow, reinterpret_cast<void*>( aParam ) );
    }

    bool RunAction( const std::string& aActionName, bool aNow, void* aParam );

    bool RunAction( const std::string& aActionName, bool aNow = false )
    {
        return RunAction( aActionName, aNow, (void*) NULL );
    }

    /**
     * Function RunAction()
     * Runs the specified action.
     *
     * This function will only return if the action has been handled when the action is run
     * immediately (aNow = true), otherwise it will always return false.
     *
     * @param aAction is the action to be invoked.
     * @param aNow decides if the action has to be run immediately or after the current coroutine
     * is preemptied.
     * @param aParam is an optional parameter that might be used by the invoked action. Its meaning
     * depends on the action.
     *
     * @return True if the action was handled immediately
     */
    template <typename T>
    bool RunAction( const TOOL_ACTION& aAction, bool aNow = false, T aParam = NULL )
    {
        return RunAction( aAction, aNow, reinterpret_cast<void*>( aParam ) );
    }

    bool RunAction( const TOOL_ACTION& aAction, bool aNow, void* aParam );

    bool RunAction( const TOOL_ACTION& aAction, bool aNow = false )
    {
        return RunAction( aAction, aNow, (void*) NULL );
    }

    const std::map<std::string, TOOL_ACTION*>& GetActions();

    /**
     * Function PrimeTool()
     * "Primes" a tool by sending a cursor left-click event with the mouse position set
     * to the passed in position.
     *
     * @param aPosition is the mouse position to use in the event
     */
    void PrimeTool( const VECTOR2D& aPosition );

    ///> @copydoc ACTION_MANAGER::GetHotKey()
    int GetHotKey( const TOOL_ACTION& aAction );

    ACTION_MANAGER* GetActionManager() { return m_actionMgr; }

    /**
     * Function FindTool()
     * Searches for a tool with given ID.
     *
     * @param aId is the ID number of the requested tool.
     * @return Pointer to the requested tool or NULL in case of failure.
     */
    TOOL_BASE* FindTool( int aId ) const;

    /**
     * Function FindTool()
     * Searches for a tool with given name.
     *
     * @param aName is the name of the requested tool.
     * @return Pointer to the requested tool or NULL in case of failure.
     */
    TOOL_BASE* FindTool( const std::string& aName ) const;

    /*
     * Function GetTool()
     * Returns the tool of given type or NULL if there is no such tool registered.
     */
    template<typename T>
    T* GetTool()
    {
        std::map<const char*, TOOL_BASE*>::iterator tool = m_toolTypes.find( typeid( T ).name() );

        if( tool != m_toolTypes.end() )
            return static_cast<T*>( tool->second );

        return NULL;
    }

    /**
     * Function DeactivateTool()
     * Deactivates the currently active tool.
     */
    void DeactivateTool();


    /**
     * Function IsToolActive()
     * Returns true if a tool with given id is active (executing)
     */
     bool IsToolActive( TOOL_ID aId ) const;


    /**
     * Function ResetTools()
     * Resets all tools (i.e. calls their Reset() method).
     */
    void ResetTools( TOOL_BASE::RESET_REASON aReason );

    /**
     * Function InitTools()
     * Initializes all registered tools. If a tool fails during the initialization, it is
     * deactivated and becomes unavailable for further use. Initialization should be done
     * only once.
     */
    void InitTools();

    /**
     * Propagates an event to tools that requested events of matching type(s).
     * @param aEvent is the event to be processed.
     * @return true if the event is a managed hotkey
     */
    bool ProcessEvent( const TOOL_EVENT& aEvent );

    /**
     * Puts an event to the event queue to be processed at the end of event processing cycle.
     * @param aEvent is the event to be put into the queue.
     */
    inline void PostEvent( const TOOL_EVENT& aEvent )
    {
        m_eventQueue.push_back( aEvent );
    }

    /**
     * Sets the work environment (model, view, view controls and the parent window).
     * These are made available to the tool. Called by the parent frame when it is set up.
     */
    void SetEnvironment( EDA_ITEM* aModel, KIGFX::VIEW* aView,
                         KIGFX::VIEW_CONTROLS* aViewControls, TOOLS_HOLDER* aFrame );

    /* Accessors for the environment objects (view, model, etc.) */
    KIGFX::VIEW* GetView() const
    {
        return m_view;
    }

    inline KIGFX::VIEW_CONTROLS* GetViewControls() const
    {
        return m_viewControls;
    }

    VECTOR2D GetMousePosition();
    VECTOR2D GetCursorPosition();

    inline EDA_ITEM* GetModel() const
    {
        return m_model;
    }

    inline TOOLS_HOLDER* GetToolHolder() const { return m_frame; }

    /**
     * Returns id of the tool that is on the top of the active tools stack
     * (was invoked the most recently).
     * @return Id of the currently used tool.
     */
    inline int GetCurrentToolId() const
    {
        return m_activeTools.empty() ? -1 : m_activeTools.front();
    }

    /**
     * Returns the tool that is on the top of the active tools stack
     * (was invoked the most recently).
     * @return Pointer to the currently used tool.
     */
    inline TOOL_BASE* GetCurrentTool() const
    {
        return FindTool( GetCurrentToolId() );
    }

    /**
     * Returns the TOOL_STATE object representing the state of the active tool. If there are no
     * tools active, it returns nullptr.
     */
    TOOL_STATE* GetCurrentToolState() const
    {
        auto it = m_toolIdIndex.find( GetCurrentToolId() );
        return ( it != m_toolIdIndex.end() ) ? it->second : nullptr;
    }

    /**
     * Returns priority of a given tool. Higher number means that the tool is closer to the
     * beginning of the active tools queue (i.e. receives events earlier, tools with lower
     * priority receive events later).
     * @param aToolId is the id of queried tool.
     * @return The priority of a given tool. If returned number is negative, then it means that
     * the tool id is invalid or the tool is not active.
     */
    int GetPriority( int aToolId ) const;

    /**
     * Defines a state transition - the events that cause a given handler method in the tool
     * to be called. Called by TOOL_INTERACTIVE::Go(). May be called from a coroutine context.
     */
    void ScheduleNextState( TOOL_BASE* aTool, TOOL_STATE_FUNC& aHandler,
            const TOOL_EVENT_LIST& aConditions );

    /**
     * Clears the state transition map for a tool
     * @param aTool is the tool that should have the transition map cleared.
     */
    void ClearTransitions( TOOL_BASE* aTool );

    void RunMainStack( TOOL_BASE* aTool, std::function<void()> aFunc );

    /**
     * Updates the status bar and synchronizes toolbars.
     */
    void UpdateUI( const TOOL_EVENT& aEvent );

    /**
     * Pauses execution of a given tool until one or more events matching aConditions arrives.
     * The pause/resume operation is done through COROUTINE object.
     * Called only from coroutines.
     */
    TOOL_EVENT* ScheduleWait( TOOL_BASE* aTool, const TOOL_EVENT_LIST& aConditions );

    /**
     * Sets behaviour of the tool's context popup menu.
     * @param aTool - the parent tool
     * @param aMenu - the menu structure, defined by the tool
     * @param aTrigger - when the menu is activated:
     *  CMENU_NOW: opens the menu right now
     *  CMENU_BUTTON: opens the menu when RMB is pressed
     *  CMENU_OFF: menu is disabled.
     * May be called from a coroutine context.
     */
    void ScheduleContextMenu( TOOL_BASE* aTool, ACTION_MENU* aMenu, CONTEXT_MENU_TRIGGER aTrigger );

    /**
     * Stores an information to the system clipboard.
     * @param aText is the information to be stored.
     * @return False if error occurred.
     */
    bool SaveClipboard( const std::string& aText );

    /**
     * Returns the information currently stored in the system clipboard. If data stored in the
     * clipboard is in non-text format, empty string is returned.
     */
    std::string GetClipboard() const;

    /**
     * Returns the view controls settings for the current tool or the general settings if there is
     * no active tool.
     */
    const KIGFX::VC_SETTINGS& GetCurrentToolVC() const;

    /**
     * True while processing a context menu.
     */
    bool IsContextMenuActive()
    {
        return m_menuActive;
    }

    /**
     * Disables mouse warping after the current context menu is closed.
     * Must be called before invoking each context menu.
     * It's a good idea to call this from non-modal dialogs (e.g. DRC window).
     */
    void VetoContextMenuMouseWarp()
    {
        m_warpMouseAfterContextMenu = false;
    }

    /**
     * Function DispatchContextMenu()
     * Handles context menu related events.
     */
    void DispatchContextMenu( const TOOL_EVENT& aEvent );

    /**
     * Function dispatchHotKey()
     * Handles specific events, that are intended for TOOL_MANAGER rather than tools.
     * @param aEvent is the event to be processed.
     * @param aWhiteList an optional list of allowed actions to run
     * @return true if the event was processed and should not go any further.
     */
    bool DispatchHotKey( const TOOL_EVENT& aEvent,
                         std::set<const TOOL_ACTION*>* aWhiteList = nullptr );

private:
    typedef std::pair<TOOL_EVENT_LIST, TOOL_STATE_FUNC> TRANSITION;

    /**
     * Function dispatchInternal
     * Passes an event at first to the active tools, then to all others.
     */
    bool dispatchInternal( const TOOL_EVENT& aEvent );

    /**
     * Function dispatchActivation()
     * Checks if it is a valid activation event and invokes a proper tool.
     * @param aEvent is an event to be tested.
     * @return True if a tool was invoked, false otherwise.
     */
    bool dispatchActivation( const TOOL_EVENT& aEvent );

    /**
     * Function invokeTool()
     * Invokes a tool by sending a proper event (in contrary to runTool, which makes the tool run
     * for real).
     * @param aTool is the tool to be invoked.
     */
    bool invokeTool( TOOL_BASE* aTool );

    /**
     * Function runTool()
     * Makes a tool active, so it can receive events and react to them. Activated tool is pushed
     * on the active tools stack, so the last activated tool receives events first.
     *
     * @param aTool is the tool to be run.
     */
    bool runTool( TOOL_BASE* aTool );

    /**
     * Function finishTool()
     * Deactivates a tool and does the necessary clean up.
     *
     * @param aState is the state variable of the tool to be stopped.
     * @return m_activeTools iterator. If the tool has been completely deactivated, it points
     * to the next active tool on the list. Otherwise it is an iterator pointing to aState.
     */
    ID_LIST::iterator finishTool( TOOL_STATE* aState );

    /**
     * Function isRegistered()
     * Returns information about a tool registration status.
     *
     * @param aTool is the tool to be checked.
     * @return true if the tool is in the registered tools list, false otherwise.
     */
    bool isRegistered( TOOL_BASE* aTool ) const
    {
        return m_toolState.count( aTool ) > 0;
    }

    /**
     * Function isActive()
     * Returns information about a tool activation status.
     *
     * @param aTool is the tool to be checked.
     * @return True if the tool is on the active tools stack, false otherwise.
     */
    bool isActive( TOOL_BASE* aTool );

    /**
     * Function saveViewControls()
     * Saves the VIEW_CONTROLS settings to the tool state object. If VIEW_CONTROLS
     * settings are affected by TOOL_MANAGER, the original settings are saved.
     */
    void saveViewControls( TOOL_STATE* aState );

    /**
     * Function applyViewControls()
     * Applies VIEW_CONTROLS settings stored in a TOOL_STATE object.
     */
    void applyViewControls( TOOL_STATE* aState );

    /**
     * Main function for event processing.
     * @return true if a hotkey was handled
     */
    bool processEvent( const TOOL_EVENT& aEvent );

    /**
     * Saves the previous active state and sets a new one.
     * @param aState is the new active state. Might be null to indicate there is no new
     * active state.
     */
    void setActiveState( TOOL_STATE* aState );

    /// Index of registered tools current states, associated by tools' objects.
    TOOL_STATE_MAP m_toolState;

    /// Index of the registered tools current states, associated by tools' names.
    NAME_STATE_MAP m_toolNameIndex;

    /// Index of the registered tools current states, associated by tools' ID numbers.
    ID_STATE_MAP m_toolIdIndex;

    /// Index of the registered tools to easily lookup by their type.
    std::map<const char*, TOOL_BASE*> m_toolTypes;

    /// Stack of the active tools
    ID_LIST m_activeTools;

    /// Instance of ACTION_MANAGER that handles TOOL_ACTIONs
    ACTION_MANAGER* m_actionMgr;

    /// Original cursor position, if overridden by the context menu handler
    std::map<TOOL_ID, OPT<VECTOR2D>> m_cursorSettings;

    EDA_ITEM*             m_model;
    KIGFX::VIEW*          m_view;
    KIGFX::VIEW_CONTROLS* m_viewControls;
    TOOLS_HOLDER*         m_frame;

    /// Queue that stores events to be processed at the end of the event processing cycle.
    std::list<TOOL_EVENT> m_eventQueue;

    /// Right click context menu position.
    VECTOR2D m_menuCursor;

    bool m_warpMouseAfterContextMenu;

    /// Flag indicating whether a context menu is currently displayed.
    bool m_menuActive;

    /// Tool currently displaying a popup menu. It is negative when there is no menu displayed.
    TOOL_ID m_menuOwner;

    /// Pointer to the state object corresponding to the currently executed tool.
    TOOL_STATE* m_activeState;
};

#endif