#include "array.h"

#include <stdlib.h>
#include <string.h>

#define ARRAY_GROWTH_FACTOR 2
#define MAX(x, y) ( (x > y) ? x : y )

typedef struct _RealArray
{
    char *data;
    unsigned int length; /* Number of elements */

    unsigned int type_size;
    unsigned int capacity; /* Array capacity in elements number */
    bool clear;
} RealArray;

static void array_check_for_expand(RealArray *arr, unsigned int length);

Array *array_create(unsigned int type_size)
{
    return array_create_by_size(type_size, 0);
}

Array *array_create_by_size(unsigned int type_size, unsigned int reserved_size)
{
    RealArray *arr = malloc( sizeof(RealArray) );
    arr->capacity = 0;
    arr->data = NULL;
    arr->length = 0;
    arr->type_size = type_size;

    if(reserved_size != 0)
    {
        array_check_for_expand(arr, reserved_size);
    }

    return (Array *)arr;
}

void array_append(Array *arr, void *data)
{
    RealArray *r_arr = (RealArray *)arr;
    array_check_for_expand(r_arr, 1);

    memcpy(r_arr->data + r_arr->length * r_arr->type_size, data, r_arr->type_size);
    r_arr->length += 1;
}

void array_insert(Array *arr, int index, void *data)
{
    RealArray *r_arr = (RealArray *)arr;
    array_check_for_expand(r_arr, 1);

    /* Shift everything one place */
    memmove(r_arr->data + (index + 1) * r_arr->type_size,
            r_arr->data +  index * r_arr->type_size,
            r_arr->length * r_arr->type_size - index * r_arr->type_size);

	/* Insert the new data */
	memcpy(r_arr->data + index * r_arr->type_size, data, r_arr->type_size);

	r_arr->length += 1;
}

void array_remove(Array *arr, int index)
{

}

void array_reserve(Array *arr, unsigned int length)
{

}

unsigned int array_get_type_size(Array *arr)
{
    RealArray *r_arr = (RealArray *)arr;
    return r_arr->type_size;
}

void array_free(Array *arr)
{
    RealArray *r_arr = (RealArray *)arr;

    free(r_arr->data);
    free(r_arr);
}

static void array_check_for_expand(RealArray *arr, unsigned int length)
{
    RealArray *r_arr = (RealArray *)arr;

    unsigned int expected_size = r_arr->length + length;

    if(r_arr->capacity < expected_size)
    {
        r_arr->capacity = MAX(ARRAY_GROWTH_FACTOR * r_arr->capacity, expected_size);
        r_arr->data = realloc(r_arr->data, r_arr->capacity * r_arr->type_size);
    }
}