/* gnome-history.c - Keep history about file visitations.
   Copyright (C) 1998 Elliot Lee

   The Gnome Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The Gnome Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the Gnome Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <stdio.h>
#include <glib.h>

#include "gnome-defs.h"
#include "gnome-util.h"
#include "gnome-history.h"

#define NUM_ENTS 10

static void write_history(GList *ents);
static void free_history_list_entry(gpointer data,gpointer user_data);

/**
 * gnome_history_recently_used:
 * @filename: the file name that was recently used.
 * @filetype: the mime-type of the file used.
 * @creator: application that created this.
 * @desc: textual description of the application creator
 *
 * This routine is used to keep track of recently used file within the
 * GNOME desktop.  @filename is the file that was recently used or
 * just created.
 */
void
gnome_history_recently_used (char *filename, char *filetype,
			     char *creator, char *desc)
{
	GList *ents;
	GnomeHistoryEntry ent;

	ent = g_new (struct _GnomeHistoryEntry, 1);
	ent->filename = g_strdup (filename);
	ent->filetype = g_strdup (filetype);
	ent->creator = g_strdup (creator);
	ent->desc = g_strdup (desc);
	ents = gnome_history_get_recently_used();
	ents = g_list_append(ents, ent);
	write_history(ents);
	gnome_history_free_recently_used_list(ents);
}

/**
 * gnome_history_get_recently_used:
 *
 * Returns a GList with GnomeHistoryEntry structures with
 * all of the recently used documents.
 */
GList *
gnome_history_get_recently_used (void)
{
	GnomeHistoryEntry anent;
	GList *retval = NULL;
	FILE *infile;
	gchar *filename = gnome_util_home_file("document_history");
	gchar aline[512], **parts;
	
	infile = fopen(filename, "r");

	if(infile){
		while(fgets(aline, sizeof(aline), infile)){
			g_strchomp(aline);
			if(aline[0] == '\0') continue;
			
			parts = g_strsplit(aline, " ", 4);
			
			anent = g_malloc(sizeof(struct _GnomeHistoryEntry));
			anent->filename = parts[0];
			anent->filetype = parts[1];
			anent->creator = parts[2];
			anent->desc = parts[3];
			
			g_free(parts);
			
			retval = g_list_append(retval, anent);
		}
		fclose(infile);
	}
	g_free(filename);
	return retval;
}

static void
write_history_entry(GnomeHistoryEntry ent, FILE *outfile)
{
	fprintf(outfile, "%s %s %s %s\n",
		ent->filename, ent->filetype, ent->creator, ent->desc);
}

static void
write_history(GList *ents)
{
	FILE *outfile;
	gchar *filename = gnome_util_home_file("document_history");
	gint n;
	
	outfile = fopen(filename, "w");

	if(outfile) {
		n = g_list_length(ents) - NUM_ENTS;
		if(n < 0) n = 0;
		g_list_foreach(g_list_nth(ents, n),
			       (GFunc)write_history_entry, outfile);
		fclose(outfile);
	}
	g_free(filename);
}

/**
 * gnome_history_free_recently_used_list:
 * @alist: a list with the recently used documents
 *
 * Releases the list of recently used documents
 */
void
gnome_history_free_recently_used_list(GList *alist)
{
	g_list_foreach(alist, (GFunc) free_history_list_entry, NULL);
	g_list_free(alist);
}

static void
free_history_list_entry(gpointer data, gpointer user_data)
{
	GnomeHistoryEntry anent;
	
	anent = data;
	g_free(anent->filename);
	g_free(anent->filetype);
	g_free(anent->creator);
	g_free(anent->desc);
	g_free(anent);
}