/*

 *      Dynamic array, to store all your flims in Includes macros required

 *      to create an array of strings but as the primitive type for the

 *      array is void * providing your own duplicate_primitive and

 *      destroy_primitive functions will allow you to use the dynamic_array

 *      API to have a dynamic array containing any primitive

 *

 *      Authors: Horms <horms@vergenet.net>

 *

 *      Released under the terms of the GNU GPL

 *

 */

#include "dynamic_array.h"

/**********************************************************************

 * dynamic_array_create

 * Create a dynamic array

 * pre: block_size: blocking size to use.

 *                  DEFAULT_DYNAMIC_ARRAY_BLOCK_SIZE is used if block_size is 0

 *                  Block size refers to how many elements are prealocated

 *                  each time the array is grown.

 * return: An empty dynamic array

 *         NULL on error

 **********************************************************************/

dynamic_array_t *

dynamic_array_create(size_t block_size)

{

  dynamic_array_t *a;

  if ((a = (dynamic_array_t *) malloc(sizeof(dynamic_array_t))) == NULL) {

    return (NULL);

  }

  a->vector = NULL;

  a->count = 0;

  a->allocated_size = 0;

  a->block_size =

      block_size ? block_size : DEFAULT_DYNAMIC_ARRAY_BLOCK_SIZE;

  return (a);

}

/**********************************************************************

 * dynamic_array_destroy

 * Free an array an all the elements held within

 * pre: a: array to destroy

 *      destroy_element: pointer to funtion to destroy array elements

 *                       Function should take an argument of a pointer

 *                       and free the memory allocated to the structure

 *                       pointed to.

 * post: array is freed and destroy_element is called for all elements

 *       of the array.

 *       Nothing if a is NULL

 **********************************************************************/

void

dynamic_array_destroy(dynamic_array_t * a,

		      void (*destroy_element) (void *))

{

  if (a == NULL)

    return;

  while (a->count-- > 0) {

    destroy_element(*(a->vector + a->count));

  }

  if (a->allocated_size > 0) {

    free(a->vector);

  }

}

/**********************************************************************

 * dynamic_array_add_element

 * Add an element to a dynamic array

 * pre: a: dynamic array to add element to

 *      e: element to add

 *      destroy_element: pointer to a function to destroy an element

 *                       passed to dynamic_array_destroy on error

 *      duplicate_element: pointer to a function to duplicate an

 *                         element should take a pointer to an element

 *                         to duplicate as the only element and return

 *                         a copy of the element Any memory allocation

 *                         required should be done by this function.

 * post: element in inserted in the first unused position in the array

 *       array size is increased by a->block_size if there is

 *       insufficient room in the array to add the element.

 *       Nothing is done if e is NULL

 * return: a on success

 *         NULL if a is NULL or an error occurs

 **********************************************************************/

dynamic_array_t *

dynamic_array_add_element(dynamic_array_t * a,

			  const void *e, void (*destroy_element) (void *s), void

			  *(*duplicate_element) (const void *s))

{

  if (a == NULL)

    return (NULL);

  if (e == NULL)

    return (a);

  if (a->count == a->allocated_size) {

    a->allocated_size += a->block_size;

    if (

	(a->vector =

	 (void **) realloc(a->vector,

			   a->allocated_size * sizeof(void *))) == NULL) {

      dynamic_array_destroy(a, destroy_element);

      return (NULL);

    }

  }

  if ((*(a->vector + a->count) = (void *) duplicate_element(e)) == NULL) {

    return (NULL);

  }

  a->count++;

  return (a);

}

/**********************************************************************

 * dynamic_array_display

 * Print the contents of a dynamic array to a string

 * pre: a: dynamic array to display

 *      delimiter: character to place between elements of the array

 *      display_element: pointer to a function to display an element

 *      element_length:  pointer to a function to return the

 *                       length of an element

 * post: If a is NULL or there are no elements in a then nothing is done

 *       Else a character buffer is alocated and the contents

 *       of each array element, separated by delimiter is placed

 *       in the '\0' termintated buffer returned. It is up to the

 *       user to free this buffer.

 * return: Allocated buffer as above

 *         NULL on error, NULL a or empty a

 **********************************************************************/

char *

dynamic_array_display(dynamic_array_t * a,

		      char delimiter,

		      void (*display_element) (char *, void *),

		      size_t(*element_length) (void *))

{

  void **a_current;

  void **a_top;

  char *buffer;

  char *buffer_current;

  size_t nochar;

  size_t len = 0;

  if (a == NULL || a->count == 0) {

    return (NULL);

  }

  a_top = a->vector + a->count;

  nochar = a->count;

  for (a_current = a->vector; a_current < a_top; a_current++) {

    nochar += (len = element_length(*a_current));

    if (!len) {

      nochar--;

    }

  }

  if ((buffer = (char *) malloc(nochar)) == NULL) {

    return (NULL);

  }

  buffer_current = buffer;

  for (a_current = a->vector; a_current < a_top; a_current++) {

    if ((len = element_length(*a_current))) {

      display_element(buffer_current, *a_current);

      buffer_current += element_length(*a_current);

      *buffer_current++ = delimiter;

    }

  }

  if (len) {

    buffer_current--;

  }

  *buffer_current = '\0';

  return (buffer);

}

/**********************************************************************

 * dynamic_array_get_element

 * Get an element from an array

 * pre: a: array to retrieve element from

 *      elementno: index element in array to retrieve

 * post: no change is made to a

 * return: element requested

 *         NULL if element is beyond the number of elements in the arary

 **********************************************************************/

void *

dynamic_array_get_element(dynamic_array_t * a, size_t elementno)

{

  if (elementno > a->count)

    return (NULL);

  return (*((a->vector) + elementno));

}

/**********************************************************************

 * dynamic_array_get_count

 * Get the number of elements in the array

 * pre: array to find the number of elements in

 * return: number of elements in the array

 *         -1 if a is NULL

 **********************************************************************/

size_t

dynamic_array_get_count(dynamic_array_t * a)

{

  if (a == NULL)

    return (-1);

  return (a->count);

}

/**********************************************************************

 * dynamic_array_get_vector

 * Get the array contained in the dynamic array

 * pre: array to find the vector of

 * return: vector

 *         NULL if a is NULL

 **********************************************************************/

void *

dynamic_array_get_vector(dynamic_array_t * a)

{

  if (a == NULL)

    return (NULL);

  return (a->vector);

}

/**********************************************************************

 * dynamic_array_split_str

 * Split a string into substrings on a delimiter

 * pre: str: string to split

 *      delimiter: character to split string on

 * post: string is split.

 *       Note: The string is modified.

 * return: dynamic array containing sub_strings

 *         NULL on error

 *         string being NULL is an error state

 **********************************************************************/

dynamic_array_t *

dynamic_array_split_str(char *string, const char delimiter)

{

  dynamic_array_t *a;

  char *sub_string;

  if (string == NULL) {

    return (NULL);

  }

  if ((a = dynamic_array_create(0)) == NULL) {

    return (NULL);

  }

  while ((sub_string = strchr(string, delimiter)) != NULL) {

    *sub_string = '\0';

    if (dynamic_array_add_element(a, string, DESTROY_STR, DUP_STR) == NULL) {

      return (NULL);

    }

    string = sub_string + 1;

  }

  if (*string != '\0' &&

      dynamic_array_add_element(a, string, DESTROY_STR, DUP_STR) == NULL) {

    return (NULL);

  }

  return (a);

}