/*****************************************************************************/
/*                                                                           */
/*				    coll.c				     */
/*                                                                           */
/*			  Collection (dynamic array)			     */
/*                                                                           */
/*                                                                           */
/*                                                                           */
/* (C) 2000	 Ullrich von Bassewitz                                       */
/*               Wacholderweg 14                                             */
/*               D-70597 Stuttgart                                           */
/* EMail:        uz@musoftware.de                                            */
/*                                                                           */
/*                                                                           */
/* This software is provided 'as-is', without any expressed or implied       */
/* warranty.  In no event will the authors be held liable for any damages    */
/* arising from the use of this software.                                    */
/*                                                                           */
/* Permission is granted to anyone to use this software for any purpose,     */
/* including commercial applications, and to alter it and redistribute it    */
/* freely, subject to the following restrictions:                            */
/*                                                                           */
/* 1. The origin of this software must not be misrepresented; you must not   */
/*    claim that you wrote the original software. If you use this software   */
/*    in a product, an acknowledgment in the product documentation would be  */
/*    appreciated but is not required.                                       */
/* 2. Altered source versions must be plainly marked as such, and must not   */
/*    be misrepresented as being the original software.                      */
/* 3. This notice may not be removed or altered from any source              */
/*    distribution.                                                          */
/*                                                                           */
/*****************************************************************************/



#include <string.h>

/* common */
#include "check.h"
#include "xmalloc.h"

/* cc65 */
#include "coll.h"



/*****************************************************************************/
/*     	      	       		     Code				     */
/*****************************************************************************/



Collection* InitCollection (Collection* C)
/* Initialize a collection and return it. */
{
    /* Intialize the fields. */
    C->Count = 0;
    C->Size  = 8;
    C->Items = xmalloc (8 * sizeof (void*));

    /* Return the new struct */
    return C;
}



void DoneCollection (Collection* C)
/* Free the data for a collection. This will not free the data contained in
 * the collection.
 */
{
    /* Free the pointer array */
    xfree (C->Items);
}



Collection* NewCollection (void)
/* Create and return a new collection with the given initial size */
{
    /* Allocate memory, intialize the collection and return it */
    return InitCollection (xmalloc (sizeof (Collection)));
}



void FreeCollection (Collection* C)
/* Free a collection */
{
    /* Free the data */
    DoneCollection (C);

    /* Free the structure itself */
    xfree (C);
}



unsigned CollCount (Collection* C)
/* Return the number of items in the collection */
{
    return C->Count;
}



void CollInsert (Collection* C, void* Item, unsigned Index)
/* Insert the data at the given position in the collection */
{
    /* Check for invalid indices */
    PRECONDITION (Index <= C->Count);

    /* Grow the array if necessary */
    if (C->Count >= C->Size) {
    	/* Must grow */
       	void** NewItems;
    	C->Size *= 2;
    	NewItems = xmalloc (C->Size * sizeof (void*));
    	memcpy (NewItems, C->Items, C->Count * sizeof (void*));
    	xfree (C->Items);
    	C->Items = NewItems;
    }

    /* Move the existing elements if needed */
    if (C->Count != Index) {
    	memmove (C->Items+Index+1, C->Items+Index, (C->Count-Index) * sizeof (void*));
    }
    ++C->Count;

    /* Store the new item */
    C->Items[Index] = Item;
}



void CollAppend (Collection* C, void* Item)
/* Append an item to the end of the collection */
{
    /* Insert the item at the end of the current list */
    CollInsert (C, Item, C->Count);
}



void* CollAt (Collection* C, unsigned Index)
/* Return the item at the given index */
{
    /* Check the index */
    PRECONDITION (Index < C->Count);

    /* Return the element */
    return C->Items[Index];
}



void CollDelete (Collection* C, unsigned Index)
/* Remove the item with the given index from the collection. This will not
 * free the item itself, just the pointer. All items with higher indices
 * will get moved to a lower position.
 */
{
    /* Check the index */
    PRECONDITION (Index < C->Count);

    /* Remove the item pointer */
    --C->Count;
    memmove (C->Items+Index, C->Items+Index+1, (C->Count-Index) * sizeof (void*));
}



void CollReplace (Collection* C, void* Item, unsigned Index)
/* Replace the item at the given position. The old item will not be freed,
 * just the pointer will et replaced.
 */
{
    /* Check the index */
    PRECONDITION (Index < C->Count);

    /* Replace the item pointer */
    C->Items[Index] = Item;
}