/*
 * Copyright © 2005 Paolo Maggi
 * Copyright © 2010 Red Hat (Red Hat author: Behdad Esfahbod)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include "config.h"

#include <string.h>

#include "terminal-search-dialog.h"
#include "terminal-util.h"

#define PCRE2_CODE_UNIT_WIDTH 0
#include <pcre2.h>

#define HISTORY_MIN_ITEM_LEN 3
#define HISTORY_LENGTH 10

static GQuark
get_quark (void)
{
	static GQuark quark = 0;

	if (G_UNLIKELY (!quark))
		quark = g_quark_from_static_string ("GT:data");

	return quark;
}


#define TERMINAL_SEARCH_DIALOG_GET_PRIVATE(object) \
  ((TerminalSearchDialogPrivate *) g_object_get_qdata (G_OBJECT (object), get_quark ()))

#define GET_FLAG(widget) gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (priv->widget))

typedef struct _TerminalSearchDialogPrivate
{
	GtkWidget *search_label;
	GtkWidget *search_entry;
	GtkWidget *search_text_entry;
	GtkWidget *match_case_checkbutton;
	GtkWidget *entire_word_checkbutton;
	GtkWidget *regex_checkbutton;
	GtkWidget *backwards_checkbutton;
	GtkWidget *wrap_around_checkbutton;

	GtkListStore *store;
	GtkEntryCompletion *completion;

	/* Cached regex */
	VteRegex *regex;
	guint32 regex_compile_flags;
} TerminalSearchDialogPrivate;


static void update_sensitivity (void *unused,
                                GtkWidget *dialog);
static void response_handler (GtkWidget *dialog,
                              gint       response_id,
                              gpointer   data);
static void terminal_search_dialog_private_destroy (TerminalSearchDialogPrivate *priv);


GtkWidget *
terminal_search_dialog_new (GtkWindow   *parent)
{
	GtkWidget *dialog;
	TerminalSearchDialogPrivate *priv;
	GtkListStore *store;
	GtkEntryCompletion *completion;

	priv = g_new0 (TerminalSearchDialogPrivate, 1);

	if (!terminal_util_load_builder_resource (TERMINAL_RESOURCES_PATH_PREFIX G_DIR_SEPARATOR_S "ui/find-dialog.ui",
	                                      "find-dialog", &dialog,
	                                      "search-label", &priv->search_label,
	                                      "search-entry", &priv->search_entry,
	                                      "match-case-checkbutton", &priv->match_case_checkbutton,
	                                      "entire-word-checkbutton", &priv->entire_word_checkbutton,
	                                      "regex-checkbutton", &priv->regex_checkbutton,
	                                      "search-backwards-checkbutton", &priv->backwards_checkbutton,
	                                      "wrap-around-checkbutton", &priv->wrap_around_checkbutton,
	                                      NULL))
	{
		g_free (priv);
		return NULL;
	}

	g_object_set_qdata_full (G_OBJECT (dialog), get_quark (), priv,
	                         (GDestroyNotify) terminal_search_dialog_private_destroy);


	priv->search_text_entry = gtk_bin_get_child (GTK_BIN (priv->search_entry));
	gtk_widget_set_size_request (priv->search_entry, 300, -1);

	priv->store = store = gtk_list_store_new (1, G_TYPE_STRING);
	g_object_set (G_OBJECT (priv->search_entry),
	              "model", store,
	              "entry-text-column", 0,
	              NULL);

	priv->completion = completion = gtk_entry_completion_new ();
	gtk_entry_completion_set_model (completion, GTK_TREE_MODEL (store));
	gtk_entry_completion_set_text_column (completion, 0);
	gtk_entry_completion_set_minimum_key_length (completion, HISTORY_MIN_ITEM_LEN);
	gtk_entry_completion_set_popup_completion (completion, FALSE);
	gtk_entry_completion_set_inline_completion (completion, TRUE);
	gtk_entry_set_completion (GTK_ENTRY (priv->search_text_entry), completion);

	gtk_dialog_set_default_response (GTK_DIALOG (dialog), GTK_RESPONSE_ACCEPT);
	gtk_dialog_set_response_sensitive (GTK_DIALOG (dialog), GTK_RESPONSE_ACCEPT, FALSE);

	gtk_entry_set_activates_default (GTK_ENTRY (priv->search_text_entry), TRUE);
	g_signal_connect (priv->search_text_entry, "changed", G_CALLBACK (update_sensitivity), dialog);
	g_signal_connect (priv->regex_checkbutton, "toggled", G_CALLBACK (update_sensitivity), dialog);

	g_signal_connect (dialog, "response", G_CALLBACK (response_handler), NULL);

	if (parent)
		gtk_window_set_transient_for (GTK_WINDOW (dialog), parent);

	return GTK_WIDGET (dialog);
}

void
terminal_search_dialog_present (GtkWidget *dialog)
{
	TerminalSearchDialogPrivate *priv;

	g_return_if_fail (GTK_IS_DIALOG (dialog));

	priv = TERMINAL_SEARCH_DIALOG_GET_PRIVATE (dialog);
	g_return_if_fail (priv);

	gtk_window_present (GTK_WINDOW (dialog));
	gtk_widget_grab_focus (priv->search_text_entry);
}

static void
terminal_search_dialog_private_destroy (TerminalSearchDialogPrivate *priv)
{

	if (priv->regex)
		vte_regex_unref (priv->regex);

	g_object_unref (priv->store);
	g_object_unref (priv->completion);

	g_free (priv);
}


static void
update_sensitivity (void *unused, GtkWidget *dialog)
{
	TerminalSearchDialogPrivate *priv = TERMINAL_SEARCH_DIALOG_GET_PRIVATE (dialog);
	const gchar *search_string;
	gboolean valid;

	if (priv->regex)
	{
		vte_regex_unref (priv->regex);
		priv->regex = NULL;
	}

	search_string = gtk_entry_get_text (GTK_ENTRY (priv->search_text_entry));
	g_return_if_fail (search_string != NULL);

	valid = *search_string != '\0';

	if (valid && GET_FLAG (regex_checkbutton))
	{
		/* Check that the regex is valid */
		valid = NULL != terminal_search_dialog_get_regex (dialog);
		/* TODO show the error message somewhere */
	}

	gtk_dialog_set_response_sensitive (GTK_DIALOG (dialog), GTK_RESPONSE_ACCEPT, valid);
}

static gboolean
remove_item (GtkListStore *store,
             const gchar  *text)
{
	GtkTreeIter iter;

	g_return_val_if_fail (text != NULL, FALSE);

	if (!gtk_tree_model_get_iter_first (GTK_TREE_MODEL (store), &iter))
		return FALSE;

	do
	{
		gchar *item_text;

		gtk_tree_model_get (GTK_TREE_MODEL (store), &iter, 0, &item_text, -1);

		if (item_text != NULL && strcmp (item_text, text) == 0)
		{
			gtk_list_store_remove (store, &iter);
			g_free (item_text);
			return TRUE;
		}

		g_free (item_text);
	}
	while (gtk_tree_model_iter_next (GTK_TREE_MODEL (store), &iter));

	return FALSE;
}

static void
clamp_list_store (GtkListStore *store,
                  guint         max)
{
	GtkTreePath *path;
	GtkTreeIter iter;

	/* -1 because TreePath counts from 0 */
	path = gtk_tree_path_new_from_indices (max - 1, -1);

	if (gtk_tree_model_get_iter (GTK_TREE_MODEL (store), &iter, path))
		while (1)
			if (!gtk_list_store_remove (store, &iter))
				break;

	gtk_tree_path_free (path);
}

static void
history_entry_insert (GtkListStore *store,
                      const gchar  *text)
{
	GtkTreeIter iter;

	g_return_if_fail (text != NULL);

	if (g_utf8_strlen (text, -1) <= HISTORY_MIN_ITEM_LEN)
		return;

	/* remove the text from the store if it was already
	 * present. If it wasn't, clamp to max history - 1
	 * before inserting the new row, otherwise appending
	 * would not work */

	if (!remove_item (store, text))
		clamp_list_store (store, HISTORY_LENGTH - 1);

	gtk_list_store_insert (store, &iter, 0);
	gtk_list_store_set (store, &iter, 0, text, -1);
}

static void
response_handler (GtkWidget *dialog,
                  gint       response_id,
                  gpointer   data)
{
	TerminalSearchDialogPrivate *priv;
	const gchar *str;

	if (response_id != GTK_RESPONSE_ACCEPT)
	{
		gtk_widget_hide (dialog);
		return;
	}

	priv = TERMINAL_SEARCH_DIALOG_GET_PRIVATE (dialog);

	str = gtk_entry_get_text (GTK_ENTRY (priv->search_text_entry));
	if (*str != '\0')
		history_entry_insert (priv->store, str);
}


void
terminal_search_dialog_set_search_text (GtkWidget   *dialog,
                                        const gchar *text)
{
	TerminalSearchDialogPrivate *priv;

	g_return_if_fail (GTK_IS_DIALOG (dialog));
	g_return_if_fail (text != NULL);

	priv = TERMINAL_SEARCH_DIALOG_GET_PRIVATE (dialog);
	g_return_if_fail (priv);

	gtk_entry_set_text (GTK_ENTRY (priv->search_text_entry), text);

	gtk_dialog_set_response_sensitive (GTK_DIALOG (dialog),
	                                   GTK_RESPONSE_ACCEPT,
	                                   (*text != '\0'));
}

const gchar *
terminal_search_dialog_get_search_text (GtkWidget *dialog)
{
	TerminalSearchDialogPrivate *priv;

	g_return_val_if_fail (GTK_IS_DIALOG (dialog), NULL);

	priv = TERMINAL_SEARCH_DIALOG_GET_PRIVATE (dialog);
	g_return_val_if_fail (priv, NULL);

	return gtk_entry_get_text (GTK_ENTRY (priv->search_text_entry));
}

TerminalSearchFlags
terminal_search_dialog_get_search_flags (GtkWidget *dialog)
{
	TerminalSearchDialogPrivate *priv;
	TerminalSearchFlags flags = 0;

	g_return_val_if_fail (GTK_IS_DIALOG (dialog), flags);

	priv = TERMINAL_SEARCH_DIALOG_GET_PRIVATE (dialog);
	g_return_val_if_fail (priv, flags);

	if (GET_FLAG (backwards_checkbutton))
		flags |= TERMINAL_SEARCH_FLAG_BACKWARDS;

	if (GET_FLAG (wrap_around_checkbutton))
		flags |= TERMINAL_SEARCH_FLAG_WRAP_AROUND;

	return flags;
}

VteRegex *
terminal_search_dialog_get_regex (GtkWidget *dialog)
{
	TerminalSearchDialogPrivate *priv;
	guint32 compile_flags;
	const char *text, *pattern;

	g_return_val_if_fail (GTK_IS_DIALOG (dialog), NULL);

	priv = TERMINAL_SEARCH_DIALOG_GET_PRIVATE (dialog);
	g_return_val_if_fail (priv, NULL);

	pattern = text = terminal_search_dialog_get_search_text (dialog);

	compile_flags = PCRE2_MULTILINE | PCRE2_UTF | PCRE2_NO_UTF_CHECK;

	if (!GET_FLAG (match_case_checkbutton))
		compile_flags |= PCRE2_CASELESS;

	if (GET_FLAG (regex_checkbutton))
		compile_flags |= PCRE2_UCP;
	else
		pattern = g_regex_escape_string (text, -1);

	if (GET_FLAG (entire_word_checkbutton))
	{
		const char *old_pattern = pattern;
		pattern = g_strdup_printf ("\\b%s\\b", pattern);
		if (old_pattern != text)
			g_free ((char *) old_pattern);
	}

	if (!priv->regex || priv->regex_compile_flags != compile_flags)
	{
		priv->regex_compile_flags = compile_flags;
		if (priv->regex)
			vte_regex_unref (priv->regex);

		/* TODO Error handling */
		priv->regex = vte_regex_new_for_search(pattern, -1,
						       compile_flags, NULL);

	}

	if (pattern != text)
		g_free ((char *) pattern);

	return priv->regex;
}