#include <blue/object/array.h>
#include <blue/object/string.h>
#include <errno.h>
#include <ivy/file.h>
#include <stdlib.h>
#include <string.h>

static enum ivy_status get_name(
	struct ivy_line_source *src, char *buf, size_t count, size_t *nr_read)
{
	struct ivy_file *f = (struct ivy_file *)src;
	*nr_read = snprintf(buf, count, "%s", f->f_path);
	return IVY_OK;
}

static enum ivy_status get_row(
	struct ivy_line_source *src, size_t row, char *buf, size_t count,
	size_t *nr_read)
{
	struct ivy_file *f = (struct ivy_file *)src;
	size_t nr_rows = b_array_size(f->f_lines);

	if (row > nr_rows) {
		return IVY_ERR_EOF;
	}

	b_string *line = B_STRING(b_array_at(f->f_lines, row - 1));

	const char *line_str = b_string_ptr(line);
	size_t line_len = b_string_get_size(line, B_STRLEN_NORMAL);
	size_t copy_len = b_min(ulong, count, line_len);

	memcpy(buf, line_str, copy_len);
	buf[copy_len] = 0;
	buf[strcspn(buf, "\n")] = 0;
	*nr_read = copy_len;

	return IVY_OK;
}

static enum ivy_status readline(
	struct ivy_line_source *src, char *buf, size_t count, size_t *nr_read,
	const char *prompt)
{
	if (!count) {
		*nr_read = 0;
		return IVY_OK;
	}

	struct ivy_file *f = (struct ivy_file *)src;
	if (!fgets(buf, (int)count, f->f_fp)) {
		return feof(f->f_fp) ? IVY_ERR_EOF : IVY_ERR_IO_FAILURE;
	}

	b_string *line_str = b_string_create_from_cstr(buf);
	b_array_append(f->f_lines, B_OBJECT(line_str));
	b_string_release(line_str);

	*nr_read = strlen(buf);
	return IVY_OK;
}

enum ivy_status ivy_file_open(const char *path, struct ivy_file **out)
{
	FILE *fp = fopen(path, "r");
	if (!fp) {
		return ivy_status_from_errno(errno);
	}

	struct ivy_file *file = malloc(sizeof *file);
	if (!file) {
		fclose(fp);
		return IVY_ERR_NO_MEMORY;
	}

	memset(file, 0x0, sizeof *file);

	file->f_base.s_get_name = get_name;
	file->f_base.s_get_row = get_row;
	file->f_base.s_readline = readline;
	file->f_fp = fp;
	file->f_path = b_strdup(path);
	file->f_lines = b_array_create();

	*out = file;

	return IVY_OK;
}

void ivy_file_close(struct ivy_file *file)
{
	b_array_release(file->f_lines);
	free(file->f_path);
	fclose(file->f_fp);
	free(file);
}