/*
 * Configuration/browsing profiles
 *
 * Copyright (C) 2017  Patrick McDermott
 *
 * This file is part of Marquee.
 *
 * Marquee 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.
 *
 * Marquee 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 Marquee.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "profiles.h"

#include <gio/gio.h>
#include <glib.h>
#include <glib/gstdio.h>

#include "config.h"

struct _MqProfiles {
	gchar    *config_dir;
	gchar    *file_name;
	GKeyFile *key_file;
	gchar    *current;
	MqConfig *current_config;
};

static gboolean
create(MqProfiles *profiles)
{
	GFile             *file;
	GFileOutputStream *stream;
	gchar             *default_profile;
	gchar             *private_profile;
	MqConfig          *config;

	file = g_file_new_for_path(profiles->file_name);

	stream = g_file_create(file, G_FILE_CREATE_PRIVATE, NULL, NULL);
	g_object_unref(file);
	if (!stream) {
		return FALSE;
	}
	g_object_unref(stream);

	default_profile = mq_profiles_insert(profiles, "Default", "#0000ff");
	private_profile = mq_profiles_insert(profiles, "Private", "#6060a0");

	if (default_profile) {
		config = mq_config_new(default_profile,
				MQ_CONFIG_PROFILE_DEFAULT);
		mq_config_save(config);
		mq_config_free(config);
		mq_profiles_set_default(profiles, default_profile);
		g_free(default_profile);
	}

	if (private_profile) {
		config = mq_config_new(private_profile,
				MQ_CONFIG_PROFILE_PRIVATE);
		mq_config_save(config);
		mq_config_free(config);
		g_free(private_profile);
	}

	mq_profiles_save(profiles);

	return TRUE;
}

static void
load(MqProfiles *profiles)
{
	/* TODO: Handle parsing and ENOENT errors differently? */
	g_key_file_load_from_file(profiles->key_file, profiles->file_name,
		G_KEY_FILE_KEEP_COMMENTS | G_KEY_FILE_KEEP_TRANSLATIONS, NULL);
}

static gboolean
insert(MqProfiles *profiles, const gchar *id, const gchar *name,
	const gchar *color)
{
	gchar *dir;

	/* Make sure the profile directory can be created and doesn't already
	 * exist (or, on a case-insensitive file system, a directory by the same
	 * name but in a different case doesn't exist). */
	dir = g_build_filename(profiles->config_dir, id, NULL);
	if (g_mkdir(dir, 0700) != 0) {
		g_free(dir);
		return FALSE;
	}
	g_free(dir);

	mq_profiles_set_name(profiles, id, name);
	mq_profiles_set_color(profiles, id, color);

	return TRUE;
}

static void
changed(GFileMonitor G_GNUC_UNUSED *monitor, GFile G_GNUC_UNUSED *file,
	GFile G_GNUC_UNUSED *other_file,
	GFileMonitorEvent G_GNUC_UNUSED event_type, MqProfiles *profiles)
{
	gchar *cur_name;
	gchar *cur_color;

	if (event_type != G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT) {
		return;
	}

	/* Save the current profile. */
	if (profiles->current) {
		cur_name  = mq_profiles_get_name( profiles, profiles->current);
		cur_color = mq_profiles_get_color(profiles, profiles->current);
	}

	/* Get changes. */
	load(profiles);

	/* If another process removed the current profile, restore it.  All
	 * other processes will reread the file and see the profile re-inserted.
	 * Multiple processes of the same profile may re-insert their profile,
	 * but they should all write the same contents to the file.  But this
	 * can cause a thundering hurd as all running processes read and/or
	 * write the file in response to each other's changes. */
	if (profiles->current) {
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"  /* False positive */
		if (!g_key_file_has_group(profiles->key_file,
					profiles->current)) {
			if (insert(profiles, profiles->current,
					cur_name, cur_color))
			{
				mq_config_save(profiles->current_config);
				mq_profiles_save(profiles);
			}
		}
		g_free(cur_name);
		g_free(cur_color);
#pragma GCC diagnostic pop
	}
}

static void
monitor(MqProfiles *profiles)
{
	GFile        *file;
	GFileMonitor *monitor;

	file = g_file_new_for_path(profiles->file_name);
	monitor = g_file_monitor_file(file, G_FILE_MONITOR_NONE, NULL, NULL);
	g_signal_connect(monitor, "changed", G_CALLBACK(changed), profiles);
}

MqProfiles *
mq_profiles_new(void)
{
	MqProfiles *profiles;

	profiles = g_new0(MqProfiles, 1);

	profiles->config_dir = g_build_filename(g_get_user_config_dir(),
		PACKAGE, NULL);
	g_mkdir_with_parents(profiles->config_dir, 0700);

	profiles->file_name = g_build_filename(g_get_user_config_dir(), PACKAGE,
		"profiles", NULL);
	profiles->key_file = g_key_file_new();

	if (!create(profiles)) {
		load(profiles);
	}

	monitor(profiles);

	return profiles;
}

gchar **
mq_profiles_get_profiles(MqProfiles *profiles, gsize *length)
{
	return g_key_file_get_groups(profiles->key_file, length);
}

gchar *
mq_profiles_get_name(MqProfiles *profiles, const gchar *profile)
{
	return g_key_file_get_string(profiles->key_file, profile, "name", NULL);
}

gchar *
mq_profiles_get_color(MqProfiles *profiles, const gchar *profile)
{
	return g_key_file_get_string(profiles->key_file, profile, "color",
		NULL);
}

gboolean
mq_profiles_is_default(MqProfiles *profiles, const gchar *profile)
{
	return g_key_file_get_boolean(profiles->key_file, profile, "default",
		NULL);
}

gchar *
mq_profiles_get_default(MqProfiles *profiles)
{
	gchar  *def;
	gchar **ids;
	gsize   length;
	gsize   i;

	def = NULL;

	ids = g_key_file_get_groups(profiles->key_file, &length);
	for (i = 0; i < length; ++i) {
		if (i == 0) {
			/* In case no profile is marked as default, use the
			 * first one. */
			def = g_strdup(ids[i]);
		}
		if (g_key_file_get_boolean(profiles->key_file, ids[i],
				"default", NULL)) {
			g_free(def);
			def = g_strdup(ids[i]);
			break;
		}
	}
	g_strfreev(ids);

	return def;
}

gchar *
mq_profiles_get_current(MqProfiles *profiles)
{
	return g_strdup(profiles->current);
}

MqConfig *
mq_profiles_get_current_config(MqProfiles *profiles)
{
	return profiles->current_config;
}

void
mq_profiles_set_name(MqProfiles *profiles, const gchar *profile,
	const gchar *name)
{
	g_key_file_set_string(profiles->key_file, profile, "name", name);
}

void
mq_profiles_set_color(MqProfiles *profiles, const gchar *profile,
	const gchar *color)
{
	g_key_file_set_string(profiles->key_file, profile, "color", color);
}

void
mq_profiles_set_default(MqProfiles *profiles, const gchar *profile)
{
	gchar **ids;
	gsize   length;
	gsize   i;

	ids = g_key_file_get_groups(profiles->key_file, &length);
	for (i = 0; i < length; ++i) {
		g_key_file_set_boolean(profiles->key_file, ids[i], "default",
			FALSE);
	}
	g_strfreev(ids);

	g_key_file_set_boolean(profiles->key_file, profile, "default", TRUE);
}

void
mq_profiles_set_current(MqProfiles *profiles, const gchar *profile)
{
	g_free(profiles->current);
	if (profiles->current_config) {
		mq_config_free(profiles->current_config);
	}

	if (profile && profile[0]) {
		profiles->current = g_strdup(profile);
	} else {
		profiles->current = mq_profiles_get_default(profiles);
	}
	profiles->current_config = mq_config_new(profiles->current,
		MQ_CONFIG_PROFILE_DEFAULT);
	mq_config_load(profiles->current_config);
}

gchar *
mq_profiles_insert(MqProfiles *profiles, const gchar *name, const gchar *color)
{
	gchar *id;

	/* The ID must be safe for both the file system and HTML5 "name" and
	 * "id" attributes.  To make profile directories portable to other file
	 * systems, use the lowest common denominator of allowed characters. */
	id = g_strdelimit(g_strdup(name),
		"/\\:*\"?<>|"  /* Lowest common denominator of modern FSes */
		" \t\n\f\r",   /* HTML5 "space characters" */
		'_');

	if (insert(profiles, id, name, color)) {
		return id;
	} else {
		g_free(id);
		return NULL;
	}
}

static gboolean
unlink_recursive(const gchar *dir_path)
{
	GDir        *dir;
	const gchar *entry_name;
	gchar       *entry_path;

	dir = g_dir_open(dir_path, 0, NULL);
	if (!dir) {
		return FALSE;
	}

	while ((entry_name = g_dir_read_name(dir))) {
		entry_path = g_build_filename(dir_path, entry_name, NULL);
		if (g_file_test(entry_path, G_FILE_TEST_IS_DIR)) {
			unlink_recursive(entry_path);
		}
		if (g_unlink(entry_path) != 0) {
			return FALSE;
		}
		g_free(entry_path);
	}

	g_dir_close(dir);
	if (g_rmdir(dir_path) != 0) {
		return FALSE;
	}

	return TRUE;
}

gboolean
mq_profiles_remove(MqProfiles *profiles, const gchar *profile)
{
	if (g_strcmp0(profile, profiles->current) == 0) {
		return FALSE;
	}

	return unlink_recursive(
			g_build_filename(profiles->config_dir, profile, NULL))
		&& g_key_file_remove_group(profiles->key_file, profile, NULL);
}

gboolean
mq_profiles_save(MqProfiles *profiles)
{
	/* TODO: Handle GFileError? */
	return g_key_file_save_to_file(profiles->key_file, profiles->file_name,
		NULL);
}

gboolean
mq_profile_launch(gchar *profile)
{
	static gchar *program_path = NULL;
	gchar        *argv[4];
	gboolean      success;
	GPid          child_pid;

	if (!program_path) {
#if defined(RUN_IN_PLACE) && RUN_IN_PLACE
		program_path = g_build_filename(ABS_TOP_BUILDDIR, PROGRAM_NAME,
			NULL);
#else
		program_path = g_build_filename(BINDIR, PROGRAM_NAME, NULL);
#endif
	}

	argv[0] = g_strdup(program_path);
	argv[1] = g_strdup("-P");
	argv[2] = profile;
	argv[3] = NULL;

	success = g_spawn_async(NULL, argv, NULL, G_SPAWN_DEFAULT, NULL, NULL,
		&child_pid, NULL);
	g_spawn_close_pid(child_pid);

	g_free(argv[0]);
	g_free(argv[1]);

	return success;
}