#include <sys/mman.h>

#include <stddef.h>
#include <assert.h>
#include "mem.h"
#include "slice.h"
#include "vector.h"

#define SEGMENT_LEN 8192

DEFINE_VECTOR(Vec_voidp, void *);

struct add_buf {
	Vec_voidp *segments;
	size_t size;
};

static void ab_init(struct add_buf **ab)
{
	struct add_buf *nab = mem_malloc(sizeof *nab);

	Vec_voidp_init(&nab->segments);
	nab->size = 0;
	*ab = nab;
}

static void ab_free(struct add_buf *ab)
{
	size_t len = Vec_voidp_len(ab->segments);

	for (size_t i = 0; i < len; i++)
		munmap(Vec_voidp_get(ab->segments, i), SEGMENT_LEN);

	Vec_voidp_free(ab->segments);
	mem_free(ab);
}

inline static char *new_segment()
{
	return mmap(NULL, SEGMENT_LEN, PROT_READ | PROT_WRITE,
		    MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
}

static void ab_push(struct add_buf *ab, char ch)
{
	if (++ab->size > Vec_voidp_len(ab->segments) * SEGMENT_LEN)
		Vec_voidp_push(ab->segments, new_segment());

	char *seg = (char *)Vec_voidp_get(ab->segments, ab->size / SEGMENT_LEN);
	seg[ab->size % SEGMENT_LEN] = ch;
}

struct piece {
	size_t is_origin:1;

	/* padding */

	size_t start_index;
	size_t length;
};

struct ed_buf {
	Vec_voidp *ptab;
	const char *origin;
	struct add_buf *add;
};

void eb_init(struct ed_buf **eb)
{
	Vec_voidp *ptab;
	Vec_voidp_init(&ptab);

	struct ed_buf *neb = mem_malloc(sizeof *neb);
	neb->ptab = ptab;
	neb->origin = NULL;
	ab_init(&neb->add);

	*eb = neb;
}

void eb_free(struct ed_buf *eb)
{
	Vec_voidp_free(eb->ptab);
	ab_free(eb->add);
	
	free(eb);
}

void eb_insert(struct ed_buf *eb, int ch)
{
	assert("TODO" == 0);
}

void eb_backspace(struct ed_buf *eb)
{
	assert("TODO" == 0);
}

void eb_newline(struct ed_buf *eb)
{
	assert("TODO" == 0);
}


/* set cursor */
void eb_set_cur_prev_line(struct ed_buf *eb)
{
	assert("TODO" == 0);
}

void eb_set_cur_backward(struct ed_buf *eb)
{
	assert("TODO" == 0);
}

void eb_set_cur_next_line(struct ed_buf *eb)
{
	assert("TODO" == 0);
}

void eb_set_cur_forward(struct ed_buf *eb)
{
	assert("TODO" == 0);
}


/* get */
void eb_get_line_slice(const struct ed_buf *eb, size_t pos, struct slice *sl)
{
	assert("TODO" == 0);
}

size_t eb_get_cur_col(const struct ed_buf *eb)
{
	assert("TODO" == 0);
}

size_t eb_get_cur_row(const struct ed_buf *eb)
{
	assert("TODO" == 0);
}

size_t eb_get_line_num(const struct ed_buf *eb)
{
	assert("TODO" == 0);
}


/* io */
void eb_bind(struct ed_buf *eb, const char *path)
{
	assert("TODO" == 0);
}

void eb_load_file(struct ed_buf *eb)
{
	assert("TODO" == 0);
}

void eb_save_file(struct ed_buf *eb)
{
	assert("TODO" == 0);
}