/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
/*
   Copyright (C) 2005 Novell, Inc
  
   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 2 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 Street - Suite 500,
   Boston, MA 02110-1335, USA.
  
   Author: Anders Carlsson <andersca@imendio.com>
*/

#include <config.h>
#include "nemo-search-directory.h"
#include "nemo-search-directory-file.h"

#include "nemo-directory-private.h"
#include "nemo-file.h"
#include "nemo-file-private.h"
#include "nemo-file-utilities.h"
#include "nemo-global-preferences.h"
#include "nemo-search-engine.h"
#include <eel/eel-glib-extensions.h>
#include <gtk/gtk.h>
#include <gio/gio.h>
#include <string.h>
#include <sys/time.h>

struct NemoSearchDirectoryDetails {
	NemoQuery *query;
	gboolean modified;

	NemoSearchEngine *engine;

	gboolean search_running;
	gboolean search_finished;

	GList *files;
	GHashTable *file_hash;

	GList *monitor_list;
	GList *callback_list;
	GList *pending_callback_list;
};

typedef struct {
	gboolean monitor_hidden_files;
	NemoFileAttributes monitor_attributes;

	gconstpointer client;
} SearchMonitor;

typedef struct {
	NemoSearchDirectory *search_directory;

	NemoDirectoryCallback callback;
	gpointer callback_data;

	NemoFileAttributes wait_for_attributes;
	gboolean wait_for_file_list;
	GList *file_list;
	GHashTable *non_ready_hash;
} SearchCallback;

G_DEFINE_TYPE (NemoSearchDirectory, nemo_search_directory,
	       NEMO_TYPE_DIRECTORY);

static void search_engine_hits_added (NemoSearchEngine *engine, GList *hits, NemoSearchDirectory *search);
static void search_engine_hits_subtracted (NemoSearchEngine *engine, GList *hits, NemoSearchDirectory *search);
static void search_engine_finished (NemoSearchEngine *engine, NemoSearchDirectory *search);
static void search_engine_error (NemoSearchEngine *engine, const char *error, NemoSearchDirectory *search);
static void search_callback_file_ready_callback (NemoFile *file, gpointer data);
static void file_changed (NemoFile *file, NemoSearchDirectory *search);

static void
ensure_search_engine (NemoSearchDirectory *search)
{
	if (!search->details->engine) {
		search->details->engine = nemo_search_engine_new ();
		g_signal_connect (search->details->engine, "hits-added",
				  G_CALLBACK (search_engine_hits_added),
				  search);
		g_signal_connect (search->details->engine, "hits-subtracted",
				  G_CALLBACK (search_engine_hits_subtracted),
				  search);
		g_signal_connect (search->details->engine, "finished",
				  G_CALLBACK (search_engine_finished),
				  search);
		g_signal_connect (search->details->engine, "error",
				  G_CALLBACK (search_engine_error),
				  search);
	}
}

static void
reset_file_list (NemoSearchDirectory *search)
{
	GList *list, *monitor_list;
	NemoFile *file;
	SearchMonitor *monitor;

	/* Remove file connections */
	for (list = search->details->files; list != NULL; list = list->next) {
		file = list->data;

		/* Disconnect change handler */
		g_signal_handlers_disconnect_by_func (file, file_changed, search);

		/* Remove monitors */
		for (monitor_list = search->details->monitor_list; monitor_list; 
		     monitor_list = monitor_list->next) {
			monitor = monitor_list->data;
			nemo_file_monitor_remove (file, monitor);
		}

        nemo_file_clear_search_result_data (file, (gpointer) search);

	}
	
	nemo_file_list_free (search->details->files);
	search->details->files = NULL;
}

static void
start_or_stop_search_engine (NemoSearchDirectory *search, gboolean adding)
{
	if (adding && (search->details->monitor_list ||
	    search->details->pending_callback_list) &&
	    search->details->query &&
	    !search->details->search_running) {
		/* We need to start the search engine */
		search->details->search_running = TRUE;
		search->details->search_finished = FALSE;
		ensure_search_engine (search);

        nemo_query_set_show_hidden (search->details->query,
                                    g_settings_get_boolean (nemo_preferences, NEMO_PREFERENCES_SHOW_HIDDEN_FILES));

		nemo_search_engine_set_query (search->details->engine, search->details->query);

		reset_file_list (search);

		nemo_search_engine_start (search->details->engine);
	} else if (!adding && (!search->details->monitor_list ||
		   !search->details->pending_callback_list) &&
		   search->details->engine &&
		   search->details->search_running) {
		search->details->search_running = FALSE;
		nemo_search_engine_stop (search->details->engine);

		reset_file_list (search);
	}

}

static void
file_changed (NemoFile *file, NemoSearchDirectory *search)
{
	GList list;

	list.data = file;
	list.next = NULL;

	nemo_directory_emit_files_changed (NEMO_DIRECTORY (search), &list);
}

static void
search_monitor_add (NemoDirectory *directory,
		    gconstpointer client,
		    gboolean monitor_hidden_files,
		    NemoFileAttributes file_attributes,
		    NemoDirectoryCallback callback,
		    gpointer callback_data)
{
	GList *list;
	SearchMonitor *monitor;
	NemoSearchDirectory *search;
	NemoFile *file;

	search = NEMO_SEARCH_DIRECTORY (directory);

	monitor = g_new0 (SearchMonitor, 1);
	monitor->monitor_hidden_files = monitor_hidden_files;
	monitor->monitor_attributes = file_attributes;
	monitor->client = client;

	search->details->monitor_list = g_list_prepend (search->details->monitor_list, monitor);
	
	if (callback != NULL) {
		(* callback) (directory, search->details->files, callback_data);
	}
	
	for (list = search->details->files; list != NULL; list = list->next) {
		file = list->data;

		/* Add monitors */
		nemo_file_monitor_add (file, monitor, file_attributes);
	}

	start_or_stop_search_engine (search, TRUE);
}

static void
search_monitor_remove_file_monitors (SearchMonitor *monitor, NemoSearchDirectory *search)
{
	GList *list;
	NemoFile *file;
	
	for (list = search->details->files; list != NULL; list = list->next) {
		file = list->data;

		nemo_file_monitor_remove (file, monitor);
	}
}

static void
search_monitor_destroy (SearchMonitor *monitor, NemoSearchDirectory *search)
{
	search_monitor_remove_file_monitors (monitor, search);

	g_free (monitor);
}

static void
search_monitor_remove (NemoDirectory *directory,
		       gconstpointer client)
{
	NemoSearchDirectory *search;
	SearchMonitor *monitor;
	GList *list;

	search = NEMO_SEARCH_DIRECTORY (directory);

	for (list = search->details->monitor_list; list != NULL; list = list->next) {
		monitor = list->data;

		if (monitor->client == client) {
			search->details->monitor_list = g_list_delete_link (search->details->monitor_list, list);

			search_monitor_destroy (monitor, search);

			break;
		}
	}

	start_or_stop_search_engine (search, FALSE);
}

static void
cancel_call_when_ready (gpointer key, gpointer value, gpointer user_data)
{
	SearchCallback *search_callback;
	NemoFile *file;

	file = key;
	search_callback = user_data;

	nemo_file_cancel_call_when_ready (file, search_callback_file_ready_callback,
					      search_callback);
}

static void
search_callback_destroy (SearchCallback *search_callback)
{
	if (search_callback->non_ready_hash) {
		g_hash_table_foreach (search_callback->non_ready_hash, cancel_call_when_ready, search_callback);
		g_hash_table_destroy (search_callback->non_ready_hash);
	}

	nemo_file_list_free (search_callback->file_list);

	g_free (search_callback);
}

static void
search_callback_invoke_and_destroy (SearchCallback *search_callback)
{
	search_callback->callback (NEMO_DIRECTORY (search_callback->search_directory),
				   search_callback->file_list,
				   search_callback->callback_data);

	search_callback->search_directory->details->callback_list = 
		g_list_remove (search_callback->search_directory->details->callback_list, search_callback);

	search_callback_destroy (search_callback);
}

static void
search_callback_file_ready_callback (NemoFile *file, gpointer data)
{
	SearchCallback *search_callback = data;
	
	g_hash_table_remove (search_callback->non_ready_hash, file);

	if (g_hash_table_size (search_callback->non_ready_hash) == 0) {
		search_callback_invoke_and_destroy (search_callback);
	}
}

static void
search_callback_add_file_callbacks (SearchCallback *callback)
{
	GList *file_list_copy, *list;
	NemoFile *file;

	file_list_copy = g_list_copy (callback->file_list);

	for (list = file_list_copy; list != NULL; list = list->next) {
		file = list->data;

		nemo_file_call_when_ready (file,
					       callback->wait_for_attributes,
					       search_callback_file_ready_callback,
					       callback);
	}
	g_list_free (file_list_copy);
}
	 
static SearchCallback *
search_callback_find (NemoSearchDirectory *search, NemoDirectoryCallback callback, gpointer callback_data)
{
	SearchCallback *search_callback;
	GList *list;

	for (list = search->details->callback_list; list != NULL; list = list->next) {
		search_callback = list->data;

		if (search_callback->callback == callback &&
		    search_callback->callback_data == callback_data) {
			return search_callback;
		}
	}
	
	return NULL;
}

static SearchCallback *
search_callback_find_pending (NemoSearchDirectory *search, NemoDirectoryCallback callback, gpointer callback_data)
{
	SearchCallback *search_callback;
	GList *list;

	for (list = search->details->pending_callback_list; list != NULL; list = list->next) {
		search_callback = list->data;

		if (search_callback->callback == callback &&
		    search_callback->callback_data == callback_data) {
			return search_callback;
		}
	}
	
	return NULL;
}

static GHashTable *
file_list_to_hash_table (GList *file_list)
{
	GList *list;
	GHashTable *table;

	if (!file_list)
		return NULL;

	table = g_hash_table_new (NULL, NULL);

	for (list = file_list; list != NULL; list = list->next) {
		g_hash_table_insert (table, list->data, list->data);
	}

	return table;
}

static void
search_call_when_ready (NemoDirectory *directory,
			NemoFileAttributes file_attributes,
			gboolean wait_for_file_list,
			NemoDirectoryCallback callback,
			gpointer callback_data)
{
	NemoSearchDirectory *search;
	SearchCallback *search_callback;

	search = NEMO_SEARCH_DIRECTORY (directory);

	search_callback = search_callback_find (search, callback, callback_data);
	if (search_callback == NULL) {
		search_callback = search_callback_find_pending (search, callback, callback_data);
	}
	
	if (search_callback) {
		g_warning ("tried to add a new callback while an old one was pending");
		return;
	}

	search_callback = g_new0 (SearchCallback, 1);
	search_callback->search_directory = search;
	search_callback->callback = callback;
	search_callback->callback_data = callback_data;
	search_callback->wait_for_attributes = file_attributes;
	search_callback->wait_for_file_list = wait_for_file_list;

	if (wait_for_file_list && !search->details->search_finished) {
		/* Add it to the pending callback list, which will be
		 * processed when the directory has finished loading
		 */
		search->details->pending_callback_list = 
			g_list_prepend (search->details->pending_callback_list, search_callback);

		/* We might need to start the search engine */
		start_or_stop_search_engine (search, TRUE);
	} else {
		search_callback->file_list = nemo_file_list_copy (search->details->files);
		search_callback->non_ready_hash = file_list_to_hash_table (search->details->files);

		if (!search_callback->non_ready_hash) {
			/* If there are no ready files, we invoke the callback
			   with an empty list.
			*/
			search_callback_invoke_and_destroy (search_callback);
		} else {
			search->details->callback_list = g_list_prepend (search->details->callback_list, search_callback);
			search_callback_add_file_callbacks (search_callback);
		}
	}
}

static void
search_cancel_callback (NemoDirectory *directory,
			NemoDirectoryCallback callback,
			gpointer callback_data)
{
	NemoSearchDirectory *search;
	SearchCallback *search_callback;

	search = NEMO_SEARCH_DIRECTORY (directory);
	search_callback = search_callback_find (search, callback, callback_data);
	
	if (search_callback) {
		search->details->callback_list = g_list_remove (search->details->callback_list, search_callback);
		
		search_callback_destroy (search_callback);
		
		return;
	} 

	/* Check for a pending callback */
	search_callback = search_callback_find_pending (search, callback, callback_data);

	if (search_callback) {
		search->details->pending_callback_list = g_list_remove (search->details->pending_callback_list, search_callback);

		search_callback_destroy (search_callback);

		/* We might need to stop the search engine now */
		start_or_stop_search_engine (search, FALSE);
	}
}


static void
search_engine_hits_added (NemoSearchEngine *engine, GList *hits, 
			  NemoSearchDirectory *search)
{
	GList *hit_list;
	GList *file_list;
	NemoFile *file;
    FileSearchResult *fsr;
	SearchMonitor *monitor;
	GList *monitor_list;

	file_list = NULL;

	for (hit_list = hits; hit_list != NULL; hit_list = hit_list->next) {
		fsr = (FileSearchResult *) hit_list->data;

        file = nemo_file_get_by_uri (fsr->uri);
        nemo_file_add_search_result_data (file, (gpointer) search, fsr->hits);

		for (monitor_list = search->details->monitor_list; monitor_list; monitor_list = monitor_list->next) {
			monitor = monitor_list->data;

			/* Add monitors */
			nemo_file_monitor_add (file, monitor, monitor->monitor_attributes);
		}

		g_signal_connect (file, "changed", G_CALLBACK (file_changed), search),

		file_list = g_list_prepend (file_list, file);
	}
	
	search->details->files = g_list_concat (search->details->files, file_list);

	nemo_directory_emit_files_added (NEMO_DIRECTORY (search), file_list);

	file = nemo_directory_get_corresponding_file (NEMO_DIRECTORY (search));
	nemo_file_emit_changed (file);
	nemo_file_unref (file);
}

static void
search_engine_hits_subtracted (NemoSearchEngine *engine, GList *hits, 
			       NemoSearchDirectory *search)
{
	GList *hit_list;
	GList *monitor_list;
	SearchMonitor *monitor;
	GList *file_list;
	char *uri;
	NemoFile *file;

	file_list = NULL;

	for (hit_list = hits; hit_list != NULL; hit_list = hit_list->next) {
		uri = hit_list->data;
		file = nemo_file_get_by_uri (uri);

		for (monitor_list = search->details->monitor_list; monitor_list; 
		     monitor_list = monitor_list->next) {
			monitor = monitor_list->data;
			/* Remove monitors */
			nemo_file_monitor_remove (file, monitor);
		}
		
		g_signal_handlers_disconnect_by_func (file, file_changed, search);

		search->details->files = g_list_remove (search->details->files, file);

		file_list = g_list_prepend (file_list, file);
	}
	
	nemo_directory_emit_files_changed (NEMO_DIRECTORY (search), file_list);

	nemo_file_list_free (file_list);

	file = nemo_directory_get_corresponding_file (NEMO_DIRECTORY (search));
	nemo_file_emit_changed (file);
	nemo_file_unref (file);
}

static void
search_callback_add_pending_file_callbacks (SearchCallback *callback)
{
	callback->file_list = nemo_file_list_copy (callback->search_directory->details->files);
	callback->non_ready_hash = file_list_to_hash_table (callback->search_directory->details->files);

	search_callback_add_file_callbacks (callback);
}

static void
search_engine_error (NemoSearchEngine *engine, const char *error_message, NemoSearchDirectory *search)
{
	GError *error;

	error = g_error_new_literal (G_IO_ERROR, G_IO_ERROR_FAILED,
				     error_message);
	nemo_directory_emit_load_error (NEMO_DIRECTORY (search),
					    error);
	g_error_free (error);
}

static void
search_engine_finished (NemoSearchEngine *engine, NemoSearchDirectory *search)
{
	search->details->search_finished = TRUE;

	nemo_directory_emit_done_loading (NEMO_DIRECTORY (search));

	/* Add all file callbacks */
	g_list_foreach (search->details->pending_callback_list, 
			(GFunc)search_callback_add_pending_file_callbacks, NULL);
	search->details->callback_list = g_list_concat (search->details->callback_list,
							search->details->pending_callback_list);

	g_list_free (search->details->pending_callback_list);
	search->details->pending_callback_list = NULL;
}

static void
search_force_reload (NemoDirectory *directory)
{
	NemoSearchDirectory *search;

	search = NEMO_SEARCH_DIRECTORY (directory);

	if (!search->details->query) {
		return;
	}
	
	search->details->search_finished = FALSE;

	if (!search->details->engine) {
		return;
	}

	/* Remove file monitors */
	reset_file_list (search);
	
	if (search->details->search_running) {
		nemo_search_engine_stop (search->details->engine);

        nemo_query_set_show_hidden (search->details->query,
                                    g_settings_get_boolean (nemo_preferences, NEMO_PREFERENCES_SHOW_HIDDEN_FILES));

		nemo_search_engine_set_query (search->details->engine, search->details->query);
		nemo_search_engine_start (search->details->engine);
	}
}

static gboolean
search_are_all_files_seen (NemoDirectory *directory)
{
	NemoSearchDirectory *search;

	search = NEMO_SEARCH_DIRECTORY (directory);

	return (!search->details->query ||
		search->details->search_finished);
}

static gboolean
search_is_not_empty (NemoDirectory *directory)
{
	NemoSearchDirectory *search;

	search = NEMO_SEARCH_DIRECTORY (directory);

	return search->details->files != NULL;
}

static gboolean
search_contains_file (NemoDirectory *directory,
		      NemoFile *file)
{
	NemoSearchDirectory *search;

	search = NEMO_SEARCH_DIRECTORY (directory);

	/* FIXME: Maybe put the files in a hash */
	return (g_list_find (search->details->files, file) != NULL);
}

static GList *
search_get_file_list (NemoDirectory *directory)
{
	NemoSearchDirectory *search;

	search = NEMO_SEARCH_DIRECTORY (directory);

	return nemo_file_list_copy (search->details->files);
}


static gboolean
search_is_editable (NemoDirectory *directory)
{
	return FALSE;
}

static void
search_dispose (GObject *object)
{
	NemoSearchDirectory *search;
	GList *list;

	search = NEMO_SEARCH_DIRECTORY (object);
	
	/* Remove search monitors */
	if (search->details->monitor_list) {
		for (list = search->details->monitor_list; list != NULL; list = list->next) {
			search_monitor_destroy ((SearchMonitor *)list->data, search);
		}

		g_list_free (search->details->monitor_list);
		search->details->monitor_list = NULL;
	}

	reset_file_list (search);
	
	if (search->details->callback_list) {
		/* Remove callbacks */
		g_list_foreach (search->details->callback_list,
				(GFunc)search_callback_destroy, NULL);
		g_list_free (search->details->callback_list);
		search->details->callback_list = NULL;
	}

	if (search->details->pending_callback_list) {
		g_list_foreach (search->details->pending_callback_list,
				(GFunc)search_callback_destroy, NULL);
		g_list_free (search->details->pending_callback_list);
		search->details->pending_callback_list = NULL;
	}

	if (search->details->query) {
		g_object_unref (search->details->query);
		search->details->query = NULL;
	}

	if (search->details->engine) {
		if (search->details->search_running) {
			nemo_search_engine_stop (search->details->engine);
		}
		
		g_object_unref (search->details->engine);
		search->details->engine = NULL;
	}

	G_OBJECT_CLASS (nemo_search_directory_parent_class)->dispose (object);
}

static void
search_finalize (GObject *object)
{
	NemoSearchDirectory *search;

	search = NEMO_SEARCH_DIRECTORY (object);

	g_free (search->details);

	G_OBJECT_CLASS (nemo_search_directory_parent_class)->finalize (object);
}

static void
nemo_search_directory_init (NemoSearchDirectory *search)
{
	search->details = g_new0 (NemoSearchDirectoryDetails, 1);
}

static void
nemo_search_directory_class_init (NemoSearchDirectoryClass *class)
{
	NemoDirectoryClass *directory_class;

	G_OBJECT_CLASS (class)->dispose = search_dispose;
	G_OBJECT_CLASS (class)->finalize = search_finalize;

	directory_class = NEMO_DIRECTORY_CLASS (class);

 	directory_class->are_all_files_seen = search_are_all_files_seen;
	directory_class->is_not_empty = search_is_not_empty;
	directory_class->contains_file = search_contains_file;
	directory_class->force_reload = search_force_reload;
	directory_class->call_when_ready = search_call_when_ready;
	directory_class->cancel_callback = search_cancel_callback;

	directory_class->file_monitor_add = search_monitor_add;
	directory_class->file_monitor_remove = search_monitor_remove;
	
	directory_class->get_file_list = search_get_file_list;
	directory_class->is_editable = search_is_editable;
}

char *
nemo_search_directory_generate_new_uri (void)
{
	static int counter = 0;
	char *uri;

	uri = g_strdup_printf (EEL_SEARCH_URI"//%d/", counter++);

	return uri;
}


void
nemo_search_directory_set_query (NemoSearchDirectory *search,
				     NemoQuery *query)
{
	NemoDirectory *dir;
	NemoFile *as_file;

	if (search->details->query != query) {
		search->details->modified = TRUE;
	}

	if (query) {
		g_object_ref (query);
	}

	if (search->details->query) {
		g_object_unref (search->details->query);
	}

	search->details->query = query;

	dir = NEMO_DIRECTORY (search);
	as_file = dir->details->as_file;
	if (as_file != NULL) {
		nemo_search_directory_file_update_display_name (NEMO_SEARCH_DIRECTORY_FILE (as_file));
	}
}

NemoQuery *
nemo_search_directory_get_query (NemoSearchDirectory *search)
{
	if (search->details->query != NULL) {
		return g_object_ref (search->details->query);
	}
					   
	return NULL;
}

gboolean
nemo_search_directory_is_modified (NemoSearchDirectory *search)
{
	return search->details->modified;
}
