#include <inttypes.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <sys/stat.h>
#include "index.h"
#include "macros.h"
#include "misc.h"

static int index_strlen(index_t *idx) {
	int len = 0;
	/* Get the length of the index. */
	for (index_t *i = idx; i != NULL; i = i->next) {
		const int is_last = (i->next == NULL);
		if (i->type) {
			len += format_len("%"PRIu64, i->num) + !is_last;
		} else {
			len += format_len("%s", i->name) + !is_last;
		}
	}
	return len;
}

int is_valid_index(index_t *idx) {
	int did_alloc = 0;
	char *err_str = NULL;

	/* Is the index NULL? */
	if (idx == NULL) {
		err_str = "Index is NULL.";
	/* Is the index type invalid? */
	} else if (idx->type > 1) {
		did_alloc = 1;
		err_str = calloc(format_len("Invalid index type: %u.", idx->type)+1, sizeof(char));
		sprintf(err_str, "Invalid index type: %u.", idx->type);
	/* Is this named index empty? */
	} else if (idx->type == 0 && is_empty(idx->name)) {
		err_str = "Named index is empty.";
	}

	/* Did we get an error? */
	if (err_str != NULL) {
		log_reason(LOG_ERR, "Invalid index.", err_str);
		if (did_alloc) {
			free(err_str);
		}
		/* Invalid index, return false. */
		return 0;
	/* Is there another index after this one? */
	} else if (idx->next != NULL) {
		/* Return the validity of the next index. */
		return is_valid_index(idx->next);
	}
	/* Valid index, return true. */
	return 1;
}

char *make_index_path(const char *root, index_t *idx, int path_type) {
	char *path;
	char *tmp;
	int path_len = strlen(root) + 1;
	/* Is the index invalid? */
	if (!is_valid_index(idx)) {
		return NULL;
	}

	/* Get the length of the path. */
	for (index_t *i = idx; i != NULL; i = i->next) {
		const int is_last = (i->next == NULL);
		if (i->type) {
			path_len += format_len("%"PRIu64, i->num) + !is_last;
		} else {
			path_len += format_len("%s", i->name) + !is_last;
		}
	}

	path = calloc(path_len+1, sizeof(char));
	tmp = path;

	/* Create the path. */
	tmp += sprintf(tmp, "%s/", root);
	for (index_t *i = idx; i != NULL; i = i->next) {
		const int is_last = (i->next == NULL);
		const char *delm = (path_type) ? "-" : "/";
		if (i->type) {
			tmp += sprintf(tmp, "%"PRIu64"%s", i->num, (!is_last) ? delm : "");
		} else {
			tmp += sprintf(tmp, "%s%s", i->name, (!is_last) ? delm : "");
		}
	}

	return path;
}

char *index_to_str(index_t *idx) {
	if (is_valid_index(idx)) {
		char *idx_str = calloc(index_strlen(idx)+1, sizeof(char));
		char *tmp = idx_str;
		/* Create the index. */
		for (index_t *i = idx; i != NULL; i = i->next) {
			const int is_last = (i->next == NULL);
			if (i->type) {
				tmp += sprintf(tmp, "%"PRIu64"%s", i->num, (!is_last) ? "-" : "");
			} else {
				tmp += sprintf(tmp, "%s%s", i->name, (!is_last) ? "-" : "");
			}
		}
		return idx_str;
	} else {
		return NULL;
	}
}

int index_path_exists(index_t *idx, const char *root, char **path) {
	char *dummy;
	path = (path != NULL) ? path : &dummy;
	for (int i = 0; i < 2; ++i) {
		struct stat st;
		*path = make_index_path(root, idx, i);
		/* Does the index path exist? */
		if (*path != NULL && stat(*path, &st) == 0) {
			if (path == &dummy) {
				free(*path);
				*path = NULL;
			}
			return 1;
		} else {
			free(*path);
			*path = NULL;
		}
	}
	return 0;
}