#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include "lists.h"
#include "packages.h"

void * list_filter(const char * name, const char * version,
	struct list_item_base *b, unsigned int prefix)
{
	struct list_item * t;

	/* This could be modified to do a sorted search */

	if (!b)
		return NULL;

	for (t = b->start; t; t = t->next) {
		if (prefix) {
			if (strncmp(t->name, name, strlen(t->name)) == 0) {
				t->count++;
				return (void *) t;
			}
		 } else {
			if (strcmp(t->name, name) == 0) {
				t->count++;
				return (void *) t;
			}
		}
	}
	return NULL;

}

struct list_item * insert_into_list(const char * name, const char * version,
	struct list_item_base *b)
{

	int ret;
	struct list_item * t;
	struct list_item * new = malloc(sizeof(*new));

	memset(new, 0, sizeof(*new));

	new->count = 0;
	strncpy(new->name, name, PACKAGE_NAME_LENGTH);
	strncpy(new->version, version, PACKAGE_VERSION_LENGTH);

	if (b->start == NULL) {
		b->start = new;
		goto done;
	}

	ret = strncmp(name, b->start->name, PACKAGE_NAME_LENGTH);
	if (ret < 0) {
		new->next = b->start;
		b->start = new;
		new->prev = b->start;
		new->next->prev = new;
		goto done;
	}

	for (t = b->start; t; t = t->next) {
		if (t->next == NULL) {
			t->next = new;
			new->prev = t;
			new->next = NULL;
			goto done;
		}
		ret = strncmp(name, t->name, PACKAGE_NAME_LENGTH);
		if (ret > 0) {
			/* it is after t, check next */
			ret = strncmp(name, t->next->name, PACKAGE_NAME_LENGTH);
			if (ret < 0) { /* stick it here */
				new->next = t->next;
				new->prev = t;
				t->next = new;
				t->next->prev = t;
				goto done;
			}
		}
		if (ret == 0) {
			/* it is the same */
			b->number_items--;
			free(new);
			new = t;
			goto done;
		}
	}
done:
	b->number_items++;
	return new;
}

struct list_item_base * list_setup_base(void)
{
	struct list_item_base * new_base =
		malloc(sizeof(*new_base));
	new_base->number_items = 0;
	new_base->start = NULL;
	return new_base;
}

struct list_item_base * list_load(struct list_item_base * old_base,
	const char * filename, int report_error)
{
	FILE * file;
	char buf[1024];
	unsigned int ret;
	char name[PACKAGE_NAME_LENGTH];
	char version[PACKAGE_VERSION_LENGTH];
	struct list_item_base * base;


	if (old_base)
		base = old_base;
	 else 
		base = list_setup_base();

	if ((file = fopen(filename, "r")) == NULL) {
		if (report_error) 
			printf("Opening list file %s: %s\n",
				filename, strerror(errno));
		return NULL;
	}

	while (fgets(buf, sizeof(buf), file)) {
		if (buf[0] == '#') /* skip comments */
			continue; 

		ret = sscanf(buf, "%s %s", name, version);
		switch (ret) {
		case 1: /* just a name */
			insert_into_list(name, "", base);
			break;
		case 2: /* we have a version number with it */
			insert_into_list(name, version, base);
			break;
		default: /* skip line */
			break;
		}
	}
	fclose(file);
	return base;
}