/*
 *  Copyright (C) 2000 Ximian Inc.
 *
 *  Authors: Not Zed <notzed@lostzed.mmc.com.au>
 *           Jeffrey Stedfast <fejj@ximian.com>
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <config.h>

#include <glib.h>
#include <gtk/gtkframe.h>
#include <libgnome/gnome-defs.h>
#include <libgnome/gnome-i18n.h>
#include <libgnomeui/gnome-stock.h>
#include <glade/glade.h>

#include <gal/widgets/e-unicode.h>
#include <gal/util/e-unicode-i18n.h>
#include "rule-editor.h"
#include "rule-context.h"
#include "filter-rule.h"

/* for getenv only, remove when getenv need removed */
#include <stdlib.h>

static int enable_undo;

void rule_editor_add_undo(RuleEditor *re, int type, FilterRule *rule, int rank, int newrank);
void rule_editor_play_undo(RuleEditor *re);

#define d(x) x

static void set_source(RuleEditor *re, const char *source);
static void set_sensitive(RuleEditor *re);
static FilterRule *create_rule(RuleEditor *re);

static void rule_editor_class_init(RuleEditorClass *class);
static void rule_editor_init (RuleEditor *gspaper);
static void rule_editor_finalise (GtkObject *obj);
static void rule_editor_destroy (GtkObject *obj);

#define _PRIVATE(x)(((RuleEditor *)(x))->priv)

enum {
	BUTTON_ADD,
	BUTTON_EDIT,
	BUTTON_DELETE,
	BUTTON_UP,
	BUTTON_DOWN,
	BUTTON_LAST
};

struct _RuleEditorPrivate {
	GtkButton *buttons[BUTTON_LAST];
};

static GnomeDialogClass *parent_class;

enum {
	LAST_SIGNAL
};

static guint signals[LAST_SIGNAL] = { 0 };

guint
rule_editor_get_type(void)
{
	static guint type = 0;
	
	if (!type) {
		GtkTypeInfo type_info = {
			"RuleEditor",
			sizeof (RuleEditor),
			sizeof (RuleEditorClass),
			(GtkClassInitFunc) rule_editor_class_init,
			(GtkObjectInitFunc) rule_editor_init,
			(GtkArgSetFunc) NULL,
			(GtkArgGetFunc) NULL
		};

		/* TODO: Remove when it works (or never will) */
		enable_undo = getenv("EVOLUTION_RULE_UNDO") != NULL;

		type = gtk_type_unique (gnome_dialog_get_type (), &type_info);
	}
	
	return type;
}

static void
rule_editor_class_init (RuleEditorClass *class)
{
	GtkObjectClass *object_class;
	
	object_class = (GtkObjectClass *)class;
	parent_class = gtk_type_class(gnome_dialog_get_type());
	
	object_class->finalize = rule_editor_finalise;
	object_class->destroy = rule_editor_destroy;
	
	/* override methods */
	class->set_source = set_source;
	class->set_sensitive = set_sensitive;
	class->create_rule = create_rule;
	
	/* signals */
	
	gtk_object_class_add_signals (object_class, signals, LAST_SIGNAL);
}

static void
rule_editor_init (RuleEditor *o)
{
	o->priv = g_malloc0 (sizeof (*o->priv));
}

static void
rule_editor_finalise (GtkObject *obj)
{
	RuleEditor *re = (RuleEditor *)obj;
	RuleEditorUndo *undo, *next;

	gtk_object_unref (GTK_OBJECT (re->context));
	g_free (re->priv);

	undo = re->undo_log;
	while (undo) {
		next = undo->next;
		gtk_object_unref((GtkObject *)undo->rule);
		g_free(undo);
		undo = next;
	}
	
	((GtkObjectClass *)(parent_class))->finalize (obj);
}

static void
rule_editor_destroy (GtkObject *obj)
{
	RuleEditor *re = (RuleEditor *) obj;
	
	if (re->dialog)
		gtk_widget_destroy (GTK_WIDGET (re->dialog));
	
	((GtkObjectClass *)(parent_class))->destroy (obj);
}

/**
 * rule_editor_new:
 *
 * Create a new RuleEditor object.
 * 
 * Return value: A new #RuleEditor object.
 **/
RuleEditor *
rule_editor_new (RuleContext *f, const char *source)
{
	GladeXML *gui;
	RuleEditor *o = (RuleEditor *)gtk_type_new (rule_editor_get_type ());
	GtkWidget *w;
	
	gui = glade_xml_new (FILTER_GLADEDIR "/filter.glade", "rule_editor");
	rule_editor_construct (o, f, gui, source);
	
        w = glade_xml_get_widget (gui, "rule_frame");
	gtk_frame_set_label ((GtkFrame *)w, _("Rules"));
	
	gtk_object_unref (GTK_OBJECT (gui));
	
	return o;
}

/* used internally by implementations if required */
void
rule_editor_set_sensitive (RuleEditor *re)
{
	return ((RuleEditorClass *)((GtkObject *)re)->klass)->set_sensitive(re);
}

/* used internally by implementations */
void
rule_editor_set_source (RuleEditor *re, const char *source)
{
	return ((RuleEditorClass *)((GtkObject *)re)->klass)->set_source(re, source);
}

/* factory method for "add" button */
FilterRule *
rule_editor_create_rule (RuleEditor *re)
{
	return ((RuleEditorClass *)((GtkObject *)re)->klass)->create_rule(re);
}

static FilterRule *
create_rule (RuleEditor *re)
{
	FilterRule *rule = filter_rule_new ();
	FilterPart *part;
	
	/* create a rule with 1 part in it */
	part = rule_context_next_part (re->context, NULL);
	filter_rule_add_part (rule, filter_part_clone (part));
	
	return rule;
}

static void
add_editor_clicked (GtkWidget *dialog, int button, RuleEditor *re)
{
	GtkWidget *item;
	GList *l = NULL;
	char *string;

	switch (button) {
	case 0:
		if (!filter_rule_validate (re->edit)) {
			/* no need to popup a dialog because the validate code does that. */
			return;
		}
		
		gtk_object_ref (GTK_OBJECT (re->edit));
		string = e_utf8_to_gtk_string (GTK_WIDGET (re->list), re->edit->name);
		item = gtk_list_item_new_with_label (string);
		g_free (string);
		
		gtk_object_set_data (GTK_OBJECT (item), "rule", re->edit);
		gtk_widget_show (item);
		
		l = g_list_append (l, GTK_LIST_ITEM (item));
		
		gtk_list_append_items (re->list, l);
		gtk_list_select_child (re->list, item);
		
		re->current = re->edit;
		rule_context_add_rule (re->context, re->current);

		gtk_object_ref((GtkObject *)re->current);
		rule_editor_add_undo(re, RULE_EDITOR_LOG_ADD, re->current, rule_context_get_rank_rule (re->context, re->current, re->current->source), 0);
	case 1:
	default:
		gnome_dialog_close (GNOME_DIALOG (dialog));
	case -1:
                if (re->edit) {
                        gtk_object_unref (GTK_OBJECT (re->edit));
			re->edit = NULL;
		}
		
		re->dialog = NULL;
		
		gtk_widget_set_sensitive (GTK_WIDGET (re), TRUE);
		rule_editor_set_sensitive (re);
	}
}

static void
add_editor_destroyed(GtkWidget *w, RuleEditor *re)
{
	add_editor_clicked(w, -1, re);
}

static void
rule_add (GtkWidget *widget, RuleEditor *re)
{
	GtkWidget *rules;
	
	if (re->edit != NULL)
		return;
	
	re->edit = rule_editor_create_rule (re);
	filter_rule_set_source (re->edit, re->source);
	rules = filter_rule_get_widget (re->edit, re->context);
	
	re->dialog = gnome_dialog_new (_("Add Rule"),
				       GNOME_STOCK_BUTTON_OK,
				       GNOME_STOCK_BUTTON_CANCEL,
				       NULL);
	
	gtk_window_set_default_size (GTK_WINDOW (re->dialog), 600, 400);
	gtk_window_set_policy (GTK_WINDOW (re->dialog), FALSE, TRUE, FALSE);
	gtk_widget_set_parent_window (GTK_WIDGET (re->dialog), GTK_WIDGET (re)->window);
	gtk_box_pack_start (GTK_BOX (GNOME_DIALOG (re->dialog)->vbox), rules, TRUE, TRUE, 0);
	gtk_signal_connect (GTK_OBJECT (re->dialog), "clicked", add_editor_clicked, re);
	gtk_signal_connect (GTK_OBJECT (re->dialog), "destroy", add_editor_destroyed, re);
	gtk_widget_set_sensitive (GTK_WIDGET (re), FALSE);
	
	gtk_widget_show (re->dialog);
}

static void
edit_editor_clicked (GtkWidget *dialog, int button, RuleEditor *re)
{
	GtkWidget *item;
	char *string;
	int pos;
	
	switch (button) {
	case 0:
		if (!filter_rule_validate (re->edit)) {
			/* no need to popup a dialog because the validate code does that. */
			return;
		}
		
		pos = rule_context_get_rank_rule (re->context, re->current, re->source);
		if (pos != -1) {
			item = g_list_nth_data (GTK_LIST (re->list)->children, pos);
			string = e_utf8_to_gtk_string (GTK_WIDGET (item), re->edit->name);
			gtk_label_set_text (GTK_LABEL (GTK_BIN (item)->child), string);
			g_free (string);

			rule_editor_add_undo(re, RULE_EDITOR_LOG_EDIT, filter_rule_clone(re->current), pos, 0);

			/* replace the old rule with the new rule */
			filter_rule_copy (re->current, re->edit);
		}
	case 1:
	default:
		gnome_dialog_close (GNOME_DIALOG (dialog));
	case -1:
		if (re->edit) {
			gtk_object_unref (GTK_OBJECT (re->edit));
			re->edit = NULL;
		}
		
		re->dialog = NULL;
		
		gtk_widget_set_sensitive (GTK_WIDGET (re), TRUE);
		rule_editor_set_sensitive (re);
	}
}

static void
edit_editor_destroyed(GtkWidget *w, RuleEditor *re)
{
	edit_editor_clicked(w, -1, re);
}

static void
rule_edit (GtkWidget *widget, RuleEditor *re)
{
	GtkWidget *rules;
	
	if (re->current == NULL || re->edit != NULL)
		return;
	
	re->edit = filter_rule_clone (re->current);
	
	rules = filter_rule_get_widget (re->edit, re->context);
	re->dialog = gnome_dialog_new (_("Edit Rule"),
				       GNOME_STOCK_BUTTON_OK,
				       GNOME_STOCK_BUTTON_CANCEL,
				       NULL);
	
	gnome_dialog_set_parent (GNOME_DIALOG (re->dialog), GTK_WINDOW (re));
	gtk_window_set_default_size (GTK_WINDOW (re->dialog), 600, 400);
	gtk_window_set_policy (GTK_WINDOW (re->dialog), FALSE, TRUE, FALSE);
	gtk_box_pack_start (GTK_BOX (GNOME_DIALOG (re->dialog)->vbox), rules, TRUE, TRUE, 0);
	gtk_signal_connect (GTK_OBJECT (re->dialog), "clicked", edit_editor_clicked, re);
	gtk_signal_connect (GTK_OBJECT (re->dialog), "destroy", edit_editor_destroyed, re);
	
	gtk_widget_set_sensitive (GTK_WIDGET (re), FALSE);
	
	gtk_widget_show (re->dialog);
}

static void
rule_delete (GtkWidget *widget, RuleEditor *re)
{
	int pos;
	GList *l;
	GtkListItem *item;
	
	d(printf ("delete rule\n"));
	pos = rule_context_get_rank_rule (re->context, re->current, re->source);
	if (pos != -1) {
		int len;
		
		rule_context_remove_rule (re->context, re->current);
		
		item = g_list_nth_data (GTK_LIST (re->list)->children, pos);
		l = g_list_append (NULL, item);
		gtk_list_remove_items (re->list, l);
		g_list_free (l);
		
		rule_editor_add_undo(re, RULE_EDITOR_LOG_REMOVE, re->current, rule_context_get_rank_rule(re->context, re->current, re->current->source), 0);
#if 0		
		gtk_object_unref (GTK_OBJECT (re->current));
#endif
		re->current = NULL;
		
		/* now select the next rule */
		len = g_list_length (GTK_LIST (re->list)->children);
		pos = pos >= len ? len - 1 : pos;
		gtk_list_select_item (GTK_LIST (re->list), pos);
	}
	
	rule_editor_set_sensitive (re);
}

static void
rule_move (RuleEditor *re, int from, int to)
{
	GList *l;
	GtkListItem *item;

	gtk_object_ref((GtkObject *)re->current);
	rule_editor_add_undo(re, RULE_EDITOR_LOG_RANK, re->current, rule_context_get_rank_rule(re->context, re->current, re->current->source), to);
	
	d(printf ("moving %d to %d\n", from, to));
	rule_context_rank_rule (re->context, re->current, to);
	
	item = g_list_nth_data (re->list->children, from);
	l = g_list_append (NULL, item);
	gtk_list_remove_items_no_unref (re->list, l);
	gtk_list_insert_items (re->list, l, to);			      
	gtk_list_select_child (re->list, GTK_WIDGET (item));
	
	rule_editor_set_sensitive (re);
}

static void
rule_up (GtkWidget *widget, RuleEditor *re)
{
	int pos;
	
	d(printf ("up rule\n"));
	pos = rule_context_get_rank_rule (re->context, re->current, re->source);
	if (pos > 0)
		rule_move (re, pos, pos - 1);
}

static void
rule_down (GtkWidget *widget, RuleEditor *re)
{
	int pos;
	
	d(printf ("down rule\n"));
	pos = rule_context_get_rank_rule (re->context, re->current, re->source);
	if (pos >= 0)
		rule_move (re, pos, pos + 1);
}

static struct {
	char *name;
	GtkSignalFunc func;
} edit_buttons[] = {
	{ "rule_add", rule_add },
	{ "rule_edit", rule_edit },
	{ "rule_delete", rule_delete },
	{ "rule_up", rule_up },
	{ "rule_down", rule_down },
};

static void
set_sensitive (RuleEditor *re)
{
	FilterRule *rule = NULL;
	int index = -1, count = 0;
	
	while ((rule = rule_context_next_rule(re->context, rule, re->source))) {
		if (rule == re->current)
			index = count;
		count++;
	}
	
	d(printf("index = %d count=%d\n", index, count));
	
	count--;
	
	gtk_widget_set_sensitive (GTK_WIDGET (re->priv->buttons[BUTTON_EDIT]), index != -1);
	gtk_widget_set_sensitive (GTK_WIDGET (re->priv->buttons[BUTTON_DELETE]), index != -1);
	gtk_widget_set_sensitive (GTK_WIDGET (re->priv->buttons[BUTTON_UP]), index > 0);
	gtk_widget_set_sensitive (GTK_WIDGET (re->priv->buttons[BUTTON_DOWN]), index >= 0 && index < count);
}


static void
select_rule (GtkWidget *w, GtkWidget *child, RuleEditor *re)
{
	re->current = gtk_object_get_data (GTK_OBJECT (child), "rule");
	
	g_assert (re->current);
	
	rule_editor_set_sensitive (re);
}

static gboolean
double_click (GtkWidget *widget, GdkEventButton *event, RuleEditor *re)
{
	if (re->current && event->type == GDK_2BUTTON_PRESS)
		rule_edit (widget, re);
	
	return TRUE;
}

static void
set_source (RuleEditor *re, const char *source)
{
	FilterRule *rule = NULL;
	GList *newitems = NULL;
	
	gtk_list_clear_items(GTK_LIST(re->list), 0, -1);
	
	d(printf("Checking for rules that are of type %s\n", source?source:"<nil>"));
	while ((rule = rule_context_next_rule(re->context, rule, source)) != NULL) {
		GtkWidget *item;
		char *s;
		
		d(printf("   hit %s(%s)\n", rule->name, source?source:"<nil>"));
		s = e_utf8_to_gtk_string (GTK_WIDGET (re->list), rule->name);
		item = gtk_list_item_new_with_label (s);
		g_free (s);
		gtk_object_set_data (GTK_OBJECT (item), "rule", rule);
		gtk_widget_show (GTK_WIDGET (item));
		newitems = g_list_append (newitems, item);
	}
	
	gtk_list_append_items (re->list, newitems);
	g_free (re->source);
	re->source = g_strdup (source);
	re->current = NULL;
	rule_editor_set_sensitive (re);
}

void
rule_editor_add_undo(RuleEditor *re, int type, FilterRule *rule, int rank, int newrank)
{
	RuleEditorUndo *undo;

	if (!re->undo_active && enable_undo) {
		undo = g_malloc0(sizeof(*undo));
		undo->rule = rule;
		undo->type = type;
		undo->rank = rank;
		undo->newrank = newrank;

		undo->next = re->undo_log;
		re->undo_log = undo;
	} else {
		gtk_object_unref((GtkObject *)rule);
	}
}

void
rule_editor_play_undo(RuleEditor *re)
{
	RuleEditorUndo *undo, *next;
	FilterRule *rule;

	re->undo_active = TRUE;
	undo = re->undo_log;
	re->undo_log = NULL;
	while (undo) {
		next = undo->next;
		switch (undo->type) {
		case RULE_EDITOR_LOG_EDIT:
			printf("Undoing edit on rule '%s'\n", undo->rule->name);
			rule = rule_context_find_rank_rule(re->context, undo->rank, undo->rule->source);
			if (rule) {
				printf(" name was '%s'\n", rule->name);
				filter_rule_copy(rule, undo->rule);
				printf(" name is '%s'\n", rule->name);
			} else {
				g_warning("Could not find the right rule to undo against?\n");
			}
			break;
		case RULE_EDITOR_LOG_ADD:
			printf("Undoing add on rule '%s'\n", undo->rule->name);
			rule = rule_context_find_rank_rule(re->context, undo->rank, undo->rule->source);
			if (rule)
				rule_context_remove_rule(re->context, rule);
			break;
		case RULE_EDITOR_LOG_REMOVE:
			printf("Undoing remove on rule '%s'\n", undo->rule->name);
			gtk_object_ref((GtkObject *)undo->rule);
			rule_context_add_rule(re->context, undo->rule);
			rule_context_rank_rule(re->context, undo->rule, undo->rank);
			break;
		case RULE_EDITOR_LOG_RANK:
			rule = rule_context_find_rank_rule(re->context, undo->newrank, undo->rule->source);
			if (rule)
				rule_context_rank_rule(re->context, rule, undo->rank);
			break;
		}
		gtk_object_unref((GtkObject *)undo->rule);
		g_free(undo);
		undo = next;
	}
	re->undo_active = FALSE;
}

static void
editor_clicked (GtkWidget *dialog, int button, RuleEditor *re)
{
	if (button != 0) {
		if (enable_undo)
			rule_editor_play_undo(re);
		else {
			RuleEditorUndo *undo, *next;

			undo = re->undo_log;
			re->undo_log = 0;
			while (undo) {
				next = undo->next;
				gtk_object_unref((GtkObject *)undo->rule);
				g_free(undo);
				undo = next;
			}
		}
	}
}

void
rule_editor_construct (RuleEditor *re, RuleContext *context, GladeXML *gui, const char *source)
{
	GtkWidget *w;
	int i;
	
	re->context = context;
	gtk_object_ref (GTK_OBJECT (context));
	
	gtk_window_set_policy (GTK_WINDOW (re), FALSE, TRUE, FALSE);
	
        w = glade_xml_get_widget (gui, "rule_editor");
	gtk_box_pack_start (GTK_BOX (GNOME_DIALOG (re)->vbox), w, TRUE, TRUE, 0);
	
	for (i = 0; i < BUTTON_LAST; i++) {
		re->priv->buttons[i] = (GtkButton *)w = glade_xml_get_widget (gui, edit_buttons[i].name);
		gtk_signal_connect (GTK_OBJECT (w), "clicked", edit_buttons[i].func, re);
	}
	
        re->list = (GtkList *) w = glade_xml_get_widget(gui, "rule_list");
	gtk_signal_connect (GTK_OBJECT (w), "select_child", select_rule, re);
	gtk_signal_connect (GTK_OBJECT (w), "button_press_event",
			    GTK_SIGNAL_FUNC (double_click), re);

	gtk_signal_connect (GTK_OBJECT (re), "clicked", editor_clicked, re);
	rule_editor_set_source (re, source);

	if (enable_undo) {
		gnome_dialog_append_buttons (GNOME_DIALOG (re), GNOME_STOCK_BUTTON_OK,
					     GNOME_STOCK_BUTTON_CANCEL, NULL);
	} else
		gnome_dialog_append_buttons (GNOME_DIALOG (re), GNOME_STOCK_BUTTON_OK, NULL);
}