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

#include "vector.h"
#include "util.h"

#define VECTOR_START_SIZE       8
#define VECTOR_GROW_FACTOR      2
#define ITEMSZ sizeof(int)

void
vector_init(ivector *v)
{
        assert(v);

        v->n = 0;
        v->maxsz = VECTOR_START_SIZE;
        v->data = xmalloc(ITEMSZ * VECTOR_START_SIZE);
}

void
vector_initdata(ivector *v, int *arr, size_t arrsz)
{
        assert(v && arrsz);

        v->n = arrsz;
        v->maxsz = (arrsz > VECTOR_START_SIZE) ? arrsz : VECTOR_START_SIZE;
        v->data = xmalloc(ITEMSZ * v->maxsz);
        memcpy(v->data, arr, ITEMSZ * arrsz);
}

void
vector_free(ivector *v)
{
        assert(v);

        v->n = 0;
        v->maxsz = 0;
        xfree(v->data);
        v->data = NULL;
}

size_t
vector_len(const ivector *v)
{
        assert(v);

        return v->n;
}

int *
vector_data(const ivector *v)
{
        assert(v);
        return v->data;
}

void
vector_resize(ivector *v, int n)
{
        assert(v);

        if (n <= v->maxsz) {
                v->n = n;
                return;
        }

        size_t new_maxsz = v->maxsz;
        while (new_maxsz < n) {
                new_maxsz *= VECTOR_GROW_FACTOR;
        }

        v->data = xrealloc(v->data, ITEMSZ * new_maxsz);
        
        for (size_t i = v->n; i < (size_t)n; i++) {
                v->data[i] = 0;
        }
        
        v->maxsz = new_maxsz;
        v->n = n;
}

void
vector_set(ivector *v, size_t idx, int val)
{
        assert(v && idx < v->n);
        v->data[idx] = val;
}

int
vector_get(const ivector *v, size_t idx)
{
        assert(v && idx < v->n);
        return v->data[idx];
}

void
vector_push(ivector *v, int val)
{
        assert(v);
        
        if (v->n == v->maxsz) {
                size_t new_maxsz = v->maxsz * VECTOR_GROW_FACTOR;
                v->data = xrealloc(v->data, ITEMSZ * new_maxsz);
                v->maxsz = new_maxsz;
        }
        
        v->data[v->n] = val;
        v->n++;
}

void
vector_pop(ivector *v)
{
        assert(v);
        if (v->n > 0) {
                v->n--;
        }
}

void
vector_insert(ivector *v, size_t idx, int val)
{
        assert(v && v->n >= idx);

        if (v->n == v->maxsz) {
                size_t new_maxsz = v->maxsz * VECTOR_GROW_FACTOR;
                v->data = xrealloc(v->data, ITEMSZ * new_maxsz);
                v->maxsz = new_maxsz;
        }

        for (size_t i = v->n; i > idx; i--) {
                v->data[i] = v->data[i - 1];
        }
        
        v->data[idx] = val;
        v->n++;
}

void
vector_del(ivector *v, size_t idx)
{
        assert(v && idx < v->n);

        for (size_t i = idx; i < v->n - 1; i++) {
                v->data[i] = v->data[i + 1];
        }
        
        v->n--;
}

void
vector_clear(ivector *v)
{
        vector_resize(v, 0);
}