/********************************************/
/* Definitions for the EESchema program:    */
/********************************************/

#ifndef CLASS_DRAWSHEET_PATH_H
#define CLASS_DRAWSHEET_PATH_H

#include "base_struct.h"

/** Info about complex hierarchies handling:
 * A hierarchical schematic uses sheets (hierarchical sheets) included in a
 * given sheet.  Each sheet corresponds to a schematic drawing handled by a
 * SCH_SCREEN structure.  A SCH_SCREEN structure contains drawings, and have
 * a filename to write it's data.  Also a SCH_SCREEN display a sheet number
 * and the name of the sheet.
 *
 * In simple (and flat) hierarchies a sheet is linked to a SCH_SCREEN,
 * and a SCH_SCREEN is used by only one hierarchical sheet.
 *
 * In complex hierarchies the same SCH_SCREEN (and its data) is shared between
 * more than one sheet.  Therefore subsheets (like subsheets in a SCH_SCREEN
 * shared by many sheets) can be also shared.  So the same SCH_SCREEN must
 * handle different components references and parts selection depending on
 * which sheet is currently selected, and how a given subsheet is selected.
 * 2 sheets share the same SCH_SCREEN (the same drawings) if they have the
 * same filename.
 *
 * In Kicad each component and sheet receives (when created) an unique
 * identification called Time Stamp.  So each sheet has 2 ids: its time stamp
 * (that cannot change) and its name ( that can be edited and therefore is
 * not reliable for strong identification).  Kicad uses Time Stamp ( a unique
 * 32 bit id), to identify sheets in hierarchies.
 * A given sheet in a hierarchy is fully labeled by its path (or sheet path)
 * that is the list of time stamp found to access it through the hierarchy
 * the root sheet is /.  All  other sheets have a path like /1234ABCD or
 * /4567FEDC/AA2233DD/.  This path can be displayed as human readable sheet
 * name like: / or /sheet1/include_sheet/ or /sheet2/include_sheet/
 *
 * So to know for a given SCH_SCREEN (a given schematic drawings) we must:
 *   1) Handle all references possibilities.
 *   2) When acceded by a given selected sheet, display (update) the
 *      corresponding references and sheet path
 *
 * The class SCH_SHEET_PATH handles paths used to access a sheet.  The class
 * SCH_SHEET_LIST allows to handle the full (or partial) list of sheets and
 * their paths in a complex hierarchy.  The class EDA_ScreenList allow to
 * handle the list of SCH_SCREEN. It is useful to clear or save data,
 * but is not suitable to handle the full complex hierarchy possibilities
 * (usable in flat and simple hierarchies).
 */


class SCH_MARKER;


/**
 * Class SCH_SHEET_PATH
 * handles access to a sheet by way of a path.
 * <p>
 * The member m_sheets stores the list of sheets from the first (usually
 * g_RootSheet) to a given sheet in last position.
 * The _last_ sheet is usually the sheet we want to select or reach (which is
 * what the function Last() returns).
 * Others sheets constitute the "path" from the first to the last sheet.
 */
class SCH_SHEET_PATH
{
private:
    unsigned        m_numSheets;

public:
#define DSLSZ 32          // Max number of levels for a sheet path
    SCH_SHEET*      m_sheets[DSLSZ];


public:
    SCH_SHEET_PATH();
    // ~SCH_SHEET_PATH() { };

    void Clear()
    {
        m_numSheets = 0;
    }


    unsigned GetSheetsCount()
    {
        return m_numSheets;
    }


    /** Function Cmp
     * Compare if this is the same sheet path as aSheetPathToTest
     * @param aSheetPathToTest = sheet path to compare
     * @return -1 if different, 0 if same
     */
    int              Cmp( const SCH_SHEET_PATH& aSheetPathToTest ) const;

    /** Function Last
     * returns a pointer to the last sheet of the list
     * One can see the others sheet as the "path" to reach this last sheet
     */
    SCH_SHEET*      Last();

    /** Function LastScreen
     * @return the SCH_SCREEN relative to the last sheet in list
     */
    SCH_SCREEN*      LastScreen();

    /** Function LastScreen
     * @return a pointer to the first schematic item handled by the
     * SCH_SCREEN relative to the last sheet in list
     */
    SCH_ITEM*        LastDrawList();

    /**
     * Get the last schematic item relative to the first sheet in the list.
     *
     * @return Last schematic item relative to the first sheet in the list if list
     *         is not empty.  Otherwise NULL.
     */
    SCH_ITEM*        FirstDrawList();

    /** Function Push
     * store (push) aSheet in list
     * @param aSheet = pointer to the SCH_SHEET to store in list
     * Push is used when entered a sheet to select or analyze it
     * This is like cd <directory> in directories navigation
     */
    void             Push( SCH_SHEET* aSheet );

    /** Function Pop
     * retrieves (pop) the last entered sheet and remove it from list
     * @return a SCH_SHEET* pointer to the removed sheet in list
     * Pop is used when leaving a sheet after a selection or analyze
     * This is like cd .. in directories navigation
     */
    SCH_SHEET*      Pop();

    /** Function Path
     * the path uses the time stamps which do not changes even when editing
     * sheet parameters
     * a path is something like / (root) or /34005677 or /34005677/00AE4523
     */
    wxString         Path();

    /**
     * Function PathHumanReadable
     * returns the sheet path in a human readable form, i.e. as a path made
     * from sheet names.  The the "normal" path instead uses the time
     * stamps in the path.  (Time stamps do not change even when editing
     * sheet parameters).
     */
    wxString         PathHumanReadable()  const;

    /** Function BuildSheetPathInfoFromSheetPathValue
     * Fill this with data to access to the hierarchical sheet known by its
     * path aPath
     * @param aPath = path of the sheet to reach (in non human readable format)
     * @return true if success else false
     */
    bool BuildSheetPathInfoFromSheetPathValue( const wxString& aPath,
                                               bool            aFound = false );

    /**
     * Function UpdateAllScreenReferences
     * updates the reference and the m_Multi parameter (part selection) for all
     * components on a screen depending on the actual sheet path.
     * Mandatory in complex hierarchies because sheets use the same screen
     * (basic schematic)
     * but with different references and part selections according to the
     * displayed sheet
     */
    void             UpdateAllScreenReferences();

    /**
     * Find the next schematic item in this sheet ojbect.
     *
     * @param aType - The type of schematic item object to search for.
     * @param aLastItem - Start search from aLastItem.  If no aLastItem, search from
     *                    the beginning of the list.
     * @param aWrap - Wrap around the end of the list to find the next item if aLastItem
     *                is defined.
     * @return - The next schematic item if found.  Otherwise, NULL is returned.
     */
    SCH_ITEM* FindNextItem( KICAD_T aType, SCH_ITEM* aLastItem = NULL, bool aWrap = false );

    /**
     * Find the previous schematic item in this sheet path object.
     *
     * @param aItemType - The type of schematic item object to search for.
     * @param aLastItem - Start search from aLastItem.  If no aLastItem, search from
     *                    the end of the list.
     * @param aWrap - Wrap around the beginning of the list to find the next item if aLastItem
     *                is defined.
     * @return - The previous schematic item if found.  Otherwise, NULL is returned.
     */
    SCH_ITEM* FindPreviousItem( KICAD_T aType, SCH_ITEM* aLastItem = NULL, bool aWrap = false );

    /**
     * Search this sheet path for the next item that matches the search criteria.
     *
     * @param aSearchData - Criteria to search item against.
     * @param aLastItem - Find next item after aLastItem if not NULL.
     * @return If found, Returns the next schematic item.  Otherwise, returns NULL.
     */
    SCH_ITEM* MatchNextItem( wxFindReplaceData& aSearchData, SCH_ITEM* aLastItem = NULL );

    bool operator=( const SCH_SHEET_PATH& d1 );

    bool operator==( const SCH_SHEET_PATH& d1 ) const;

    bool operator!=( const SCH_SHEET_PATH& d1 ) const;
};


/**
 * Class SCH_SHEET_LIST
 * handles the list of Sheets in a hiearchy.
 * Sheets are not unique, there can be many sheets with the same
 * filename and the same SCH_SCREEN reference.
 * The schematic (SCH_SCREEN) is shared between these sheets,
 * and component references are specific to a sheet path.
 * When a sheet is entered, component references and sheet number are updated.
 */
class SCH_SHEET_LIST
{
private:
    SCH_SHEET_PATH* m_List;
    int             m_count;     /* Number of sheets included in hierarchy,
                                  * starting at the given sheet in constructor .
                                  * the given sheet is counted
                                 */
    int             m_index;     /* internal variable to handle GetNext():
                                  * cleared by GetFirst()
                                  *  and incremented by GetNext() after
                                  * returning the next item in m_List
                                  * Also used for internal calculations in
                                  * BuildSheetList()
                                  */
    SCH_SHEET_PATH  m_currList;

public:

    /**
     * Constructor
     * builds the list of sheets from aSheet.
     * If aSheet == NULL (default) build the whole list of sheets in hierarchy.
     * So usually call it with no parameter.
     */
    SCH_SHEET_LIST( SCH_SHEET* aSheet = NULL );

    ~SCH_SHEET_LIST()
    {
        if( m_List )
            free( m_List );
        m_List = NULL;
    }

    /**
     * Function GetCount()
     * @return the number of sheets in list:
     * usually the number of sheets found in the whole hierarchy
     */
    int GetCount() { return m_count; }

    /**
     * Function GetFirst
     * @return the first item (sheet) in m_List and prepare calls to GetNext()
     */
    SCH_SHEET_PATH* GetFirst();

    /**
     * Function GetNext
     * @return the next item (sheet) in m_List or NULL if no more item in
     * sheet list
     */
    SCH_SHEET_PATH* GetNext();

    /**
     * Function GetLast
     * returns the last sheet in the sheet list.
     *
     * @return Last sheet in the list or NULL if sheet list is empty.
     */
    SCH_SHEET_PATH* GetLast();

    /**
     * Function GetPrevious
     * returns the previous sheet in the sheet list.
     *
     * @return The previous sheet in the sheet list or NULL if already at the
     *         beginning of the list.
     */
    SCH_SHEET_PATH* GetPrevious();

    /**
     * Function GetSheet
     * @return the item (sheet) in aIndex position in m_List or NULL if less
     * than index items
     * @param aIndex = index in sheet list to get the sheet
     */
    SCH_SHEET_PATH* GetSheet( int aIndex );

    /**
     * Function FindNextItem
     * searches the entire schematic for the next schematic object.
     *
     * @param aType - The type of schematic item to find.
     * @param aSheetFound - The sheet the item was found in.  NULL if the next item
     *                      is not found.
     * @param aLastItem - Find next item after aLastItem if not NULL.
     * @param aWrap - Wrap past around the end of the list of sheets.
     * @return If found, Returns the next schematic item.  Otherwise, returns NULL.
     */
    SCH_ITEM* FindNextItem( KICAD_T aType, SCH_SHEET_PATH** aSheetFound = NULL,
                            SCH_ITEM* aLastItem = NULL, bool aWrap = true );

    /**
     * Function FindPreviousItem
     * searches the entire schematic for the previous schematic item.
     *
     * @param aType - The type of schematic item to find.
     * @param aSheetFound - The sheet the item was found in.  NULL if the previous item
     *                      is not found.
     * @param aLastItem - Find the previous item before aLastItem if not NULL.
     * @param aWrap - Wrap past around the beginning of the list of sheets.
     * @return If found, the previous schematic item.  Otherwise, NULL.
     */
    SCH_ITEM* FindPreviousItem( KICAD_T aType, SCH_SHEET_PATH** aSheetFound = NULL,
                                SCH_ITEM* aLastItem = NULL, bool aWrap = true );

    /**
     * Function MatchNextItem
     * searches the entire schematic for the next item that matches the search criteria.
     *
     * @param aSearchData - Criteria to search item against.
     * @param aSheetFound - The sheet the item was found in.  NULL if the next item
     *                      is not found.
     * @param aLastItem - Find next item after aLastItem if not NULL.
     * @return If found, Returns the next schematic item.  Otherwise, returns NULL.
     */
    SCH_ITEM* MatchNextItem( wxFindReplaceData& aSearchData,
                             SCH_SHEET_PATH**   aSheetFound = NULL,
                             SCH_ITEM*          aLastItem = NULL );

private:

    /**
     * Function BuildSheetList
     * builds the list of sheets and their sheet path from \a aSheet.
     * If aSheet = g_RootSheet, the full sheet path and sheet list is built
     *
     * @param aSheet is the starting sheet from which the list is built,
     *   or NULL indicating that g_RootSheet should be used.
     */
    void           BuildSheetList( SCH_SHEET* sheet );
};

#endif // CLASS_DRAWSHEET_PATH_H
