#include "int_vector.h"

struct IntVector *newIntVector(int capacity)
{
    struct IntVector *vector = malloc(sizeof(struct IntVector));
    if(capacity <= 0) return NULL;

    vector->data = malloc(capacity * sizeof(int));
    vector->size = 0;
    vector->capacity = capacity;

    return vector;
}

void freeIntVector(struct IntVector *vector)
{
    free(vector->data);
    vector->data = NULL;
    vector->size = 0;
    vector->capacity = 0;
}

void pushIntVector(struct IntVector *vector, int value)
{
    if(vector->size < vector->capacity)
    {
        vector->data[vector->size++] = value;
    }
    else // reallocate internal buffer
    {
        int *buffer = malloc(2 * sizeof(int) * vector->capacity);
        memcpy(buffer, vector->data, sizeof(int) * vector->size);
        free(vector->data);
        vector->data = buffer;
        vector->capacity *= 2;

        vector->data[vector->size++] = value;
    }
}

bool popIntVector(struct IntVector *vector)
{
    if(vector->size > 0)
    {
        vector->size--;
        return true;
    }
    return false;
}

int *getIntVector(struct IntVector *vector, int index)
{
    if(index < 0 || index >= vector->size)
        return NULL;
    return &vector->data[index];
}