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#ifndef INCLUDED_VCL_ROADMAPWIZARD_HXX
#define INCLUDED_VCL_ROADMAPWIZARD_HXX

#include <memory>
#include <vcl/dllapi.h>
#include <vcl/wizardmachine.hxx>

namespace vcl
{
    struct RoadmapWizardImpl;

    namespace RoadmapWizardTypes
    {
        typedef sal_Int16                                   PathId;
        typedef ::std::vector< WizardTypes::WizardState >   WizardPath;
    };

    //= RoadmapWizard

    /** is - no, not a wizard for a roadmap, but the base class for wizards
        <em>supporting</em> a roadmap.

        The basic new concept introduced is a <em>path</em>:<br/>
        A <em>path</em> is a sequence of states, which are to be executed in a linear order.
        Elements in the path can be skipped, depending on choices the user makes.

        In the most simple wizards, you will have only one path consisting of <code>n</code> elements,
        which are to be visited successively.

        In a slightly more complex wizard, you will have one linear path, were certain
        steps might be skipped due to user input. For instance, the user may decide to not specify
        certain aspects of the to-be-created object (e.g. by unchecking a check box),
        and the wizard then will simply disable the step which corresponds to this step.

        In a yet more advanced wizards, you will have several paths of length <code>n1</code> and
        <code>n2</code>, which share at least the first <code>k</code> states (where <code>k</code>
        is at least 1), and an arbitrary number of other states.
    */
    class VCL_DLLPUBLIC RoadmapWizardMachine : public vcl::WizardMachine
    {
    private:
        std::unique_ptr<RoadmapWizardImpl>  m_pImpl;

    public:
        RoadmapWizardMachine(weld::Window* _pParent);
        virtual ~RoadmapWizardMachine( ) override;

        void            SetRoadmapHelpId( const OString& _rId );

        // returns whether a given state is enabled
        bool            isStateEnabled(WizardTypes::WizardState nState) const;

        // WizardDialog overridables
        virtual bool    canAdvance() const override;
        virtual void    updateTravelUI() override;

    protected:
        /** declares a valid path in the wizard

            The very first path which is declared is automatically activated.

            Note that all paths which are declared must have the very first state in
            common. Also note that due to a restriction of the very base class (WizardDialog),
            this common first state must be 0.

            You cannot declare new paths once the wizard started, so it's recommended that
            you do all declarations within your derivee's constructor.

            @see activatePath

            @param _nId
                the unique id you wish to give this path. This id can later on be used
                to refer to the path which you just declared
        */
        void    declarePath( RoadmapWizardTypes::PathId _nPathId, const RoadmapWizardTypes::WizardPath& _lWizardStates);

        /** activates a path which has previously been declared with <member>declarePath</member>

            You can only activate paths which share the first <code>k</code> states with the path
            which is previously active (if any), where <code>k</code> is the index of the
            current state within the current path.

            <example>
            Say you have paths, <code>(0,1,2,5)</code> and <code>(0,1,4,5)</code>. This means that after
            step <code>1</code>, you either continue with state <code>2</code> or state <code>4</code>,
            and after this, you finish in state <code>5</code>.<br/>
            Now if the first path is active, and your current state is <code>1</code>, then you can
            easily switch to the second path, since both paths start with <code>(0,1)</code>.<br/>
            However, if your current state is <code>2</code>, then you can not switch to the second
            path anymore.
            </example>

            @param _nPathId
                the id of the path. The path must have been declared (under this id) with
                <member>declarePath</member> before it can be activated.

            @param _bDecideForIt
                If <TRUE/>, the path will be completely activated, even if it is a conflicting path
                (i.e. there is another path which shares the first <code>k</code> states with
                the to-be-activated path.)<br/>
                If <FALSE/>, then the new path is checked for conflicts with other paths. If such
                conflicts exists, the path is not completely activated, but only up to the point
                where it does <em>not</em> conflict.<br/>
                With the paths in the example above, if you activate the second path (when both are
                already declared), then only steps <code>0</code> and <code>1</code> are activated,
                since they are common to both paths.
        */
        void    activatePath( RoadmapWizardTypes::PathId _nPathId, bool _bDecideForIt = false );

        /** determine the next state to travel from the given one

            This method (which is declared in WizardMachine and overwritten here)
            ensures that traveling happens along the active path.

            @see activatePath
        */
        virtual WizardTypes::WizardState determineNextState(WizardTypes::WizardState nCurrentState) const override;

        /** en- or disables a state

            In the wizard's roadmap, states to travel to can be freely chosen. To prevent
            users from selecting a state which is currently not available, you can declare this
            state as being disabled.

            A situation where you need this may be when you have a checkbox which, when checked
            by the user, enables a page with additional settings. As long as this checkbox is
            not checked, the respective state would be disabled.

            Note that in theory, you can declare multiple paths, instead of disabling states.
            For instance, if you have a path where one state can be potentially disabled, then
            you could declare a second path, which does not contain this state. However, the
            disadvantage is that then, not the complete path would be visible in the roadmap,
            but only all steps up to the point where the both paths diverge.<br/>
            Another disadvantage is that the number of needed paths grows exponentially with
            the number of states which can be potentially disabled.

            @see declarePath
        */
        void    enableState(WizardTypes::WizardState nState, bool _bEnable = true);

        /** returns true if and only if the given state is known in at least one declared path
        */
        bool    knowsState(WizardTypes::WizardState nState) const;

        // WizardMachine overriables
        virtual void            enterState(WizardTypes::WizardState nState) override;

        /** returns a human readable name for a given state

            There is a default implementation for this method, which returns the display name
            as given in a call to describeState. If there is no description for the given state,
            this is worth an assertion in a non-product build, and then an empty string is
            returned.
        */
        virtual OUString  getStateDisplayName(WizardTypes::WizardState nState) const;

    private:
        DECL_DLLPRIVATE_LINK( OnRoadmapItemSelected, const OString&, bool );

        /** updates the roadmap control to show the given path, as far as possible
            (modulo conflicts with other paths)
        */
        VCL_DLLPRIVATE void implUpdateRoadmap( );
    };
} // namespace vcl


#endif // OOO_ INCLUDED_VCL_ROADMAPWIZARD_HXX

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