#include "settings.h"

static void print_config_error(GError *error) {
	if (error == NULL) return;

	if (!g_error_matches(error, G_KEY_FILE_ERROR, G_KEY_FILE_ERROR_KEY_NOT_FOUND) && !g_error_matches(error, G_KEY_FILE_ERROR, G_KEY_FILE_ERROR_GROUP_NOT_FOUND)) {
		g_printerr("Config error: %s\n", error->message);
	}
}

void print_config(config_t *config) {
#define EXPAND_GROUP(group_name, members) \
	g_print("[%s]\n", #group_name); \
	members

#define EXPAND_GROUP_MEMBER(member, key_type) \
	g_print("%s="FORMAT_FOR_KEY_TYPE(key_type)"\n", #member, config->member);

	EXPAND_CONFIG

#undef EXPAND_GROUP
#undef EXPAND_GROUP_MEMBER
}

void load_config_from_key_file(config_t *config, GKeyFile *key_file) {
	g_print("Loading config from key file\n");
	GError *error = NULL;
	gchar *group_name;

#define EXPAND_GROUP(name, members) \
	group_name = #name; \
	if (g_key_file_has_group(key_file, group_name)) { \
		members \
	}

#define EXPAND_GROUP_MEMBER(member, key_type) \
	config->member = g_key_file_get_##key_type(key_file, group_name, #member, &error); \
	print_config_error(error); \
	g_clear_error(&error);

	EXPAND_CONFIG

	if (config->rewind_duration > 600) {
		g_warning("Setting Emulation.rewind_duration too high might affect performance.\n");
	}

#undef EXPAND_GROUP
#undef EXPAND_GROUP_MEMBER
}

void save_config_to_key_file(config_t *config, GKeyFile *key_file) {
	g_print("Saving config to key file\n");
	GError *error = NULL;
	gchar *group_name;

#define EXPAND_GROUP(name, members) \
	group_name = #name; \
	members

#define EXPAND_GROUP_MEMBER_IF_0(member, key_type) \
	g_key_file_set_##key_type(key_file, group_name, #member, config->member);

#define EXPAND_GROUP_MEMBER_IF_1(member, key_type) \
	if (config->member != NULL) { \
		g_key_file_set_##key_type(key_file, group_name, #member, config->member); \
	} \
	else if (g_key_file_has_key(key_file, group_name, #member, &error)) { \
		if (error != NULL) { \
			g_printerr("%s\n", error->message); \
			g_clear_error(&error); \
		} \
		g_key_file_remove_key(key_file, group_name, #member, &error); \
		if (error != NULL) { \
			g_printerr("%s\n", error->message); \
			g_clear_error(&error); \
		} \
	}

#define EXPAND_GROUP_MEMBER_IF_EVAL(y, member, key_type) EXPAND_GROUP_MEMBER_IF_ ## y(member, key_type)
#define EXPAND_GROUP_MEMBER_IF(member, key_type, is_pointer) EXPAND_GROUP_MEMBER_IF_EVAL(is_pointer, member, key_type)
#define EXPAND_GROUP_MEMBER(member, key_type) EXPAND_GROUP_MEMBER_IF(member, key_type, GTYPE_IS_POINTER(key_type))
	
	EXPAND_CONFIG

#undef EXPAND_GROUP
#undef EXPAND_GROUP_MEMBER
#undef EXPAND_GROUP_MEMBER_IF
#undef EXPAND_GROUP_MEMBER_IF_EVAL
#undef EXPAND_GROUP_MEMBER_IF_0
#undef EXPAND_GROUP_MEMBER_IF_1
}

void init_settings(gchar *path, GtkWindow *preferences) {
	free_settings();
	key_file = g_key_file_new();

	if (path != NULL) {
		settings_file_path = path;
	}
	else {
		settings_file_path = g_build_filename(g_get_user_config_dir(), SETTINGS_FILE, NULL);
	}

	load_settings();
}

int load_settings(void) {
	GError *error = NULL;

	g_print("Trying to load settings from %s\n", settings_file_path);

	if (!g_key_file_load_from_file(key_file, settings_file_path, G_KEY_FILE_KEEP_COMMENTS | G_KEY_FILE_KEEP_TRANSLATIONS, &error)) {
		if (error->domain == G_FILE_ERROR) {
			g_warning("Unable to load %s: %s", settings_file_path, error->message);
		}
		else if (error->domain == G_KEY_FILE_ERROR) {
			g_warning("Failed to parse %s: %s", settings_file_path, error->message);
		}

		g_error_free(error);
		return -1;
	}

	load_config_from_key_file(&config, key_file);
	print_config(&config);

	return 0;
}

void save_settings(void) {
	GError *error = NULL;

	g_print("Trying to save settings to %s\n", settings_file_path);
	
	save_config_to_key_file(&config, key_file);

	if (!g_key_file_save_to_file(key_file, settings_file_path, &error)) {
		g_warning ("Failed to save %s: %s", settings_file_path, error->message);
		g_error_free(error);
		return;
	}
}

void free_settings(void) {
	if (key_file != NULL) {
		g_key_file_free(key_file);
		key_file = NULL;
	}
}

enum menubar_override get_show_menubar(void) {
	if (config.menubar_override == NULL) goto default_value;

	if (g_strcmp0(config.menubar_override, "show") == 0) {
		return MENUBAR_SHOW;
	}
	else if (g_strcmp0(config.menubar_override, "hide") == 0) {
		return MENUBAR_HIDE;
	}

	// This should not happen
	g_warning("Unknown menubar setting: %s\nFalling back to “Auto”\n", config.menubar_override);
	default_value: return MENUBAR_AUTO;
}

void set_show_menubar(enum menubar_override value) {
	switch (value) {
		case MENUBAR_AUTO:
			config.menubar_override = "auto";
			break;
		case MENUBAR_SHOW:
			config.menubar_override = "show";
			break;
		case MENUBAR_HIDE:
			config.menubar_override = "hide";
			break;
	}
}

GB_color_correction_mode_t get_color_correction_mode(void) {
	if (config.color_correction_id == NULL) goto default_value;

	if (g_strcmp0(config.color_correction_id, "disabled") == 0) {
		return GB_COLOR_CORRECTION_DISABLED;
	}
	else if (g_strcmp0(config.color_correction_id, "correct_color_curves") == 0) {
		return GB_COLOR_CORRECTION_CORRECT_CURVES;
	}
	else if (g_strcmp0(config.color_correction_id, "emulate_hardware") == 0) {
		return GB_COLOR_CORRECTION_EMULATE_HARDWARE;
	}
	else if (g_strcmp0(config.color_correction_id, "preserve_brightness") == 0) {
		return GB_COLOR_CORRECTION_PRESERVE_BRIGHTNESS;
	}

	// This should not happen
	g_warning("Unknown color correction mode: %s\nFalling back to “Emulate Hardware”\n", config.color_correction_id);
	default_value: return GB_COLOR_CORRECTION_EMULATE_HARDWARE;
}

void set_color_correction_mode(GB_color_correction_mode_t mode) {
	switch (mode) {
		case GB_COLOR_CORRECTION_DISABLED:
			config.color_correction_id = "disabled";
			break;
		case GB_COLOR_CORRECTION_CORRECT_CURVES:
			config.color_correction_id = "correct_color_curves";
			break;
		case GB_COLOR_CORRECTION_EMULATE_HARDWARE:
			config.color_correction_id = "emulate_hardware";
			break;
		case GB_COLOR_CORRECTION_PRESERVE_BRIGHTNESS:
			config.color_correction_id = "preserve_brightness";
			break;
	}
}

GB_highpass_mode_t get_highpass_mode(void) {
	if (config.high_pass_filter_id == NULL) goto default_value;

	if (g_strcmp0(config.high_pass_filter_id, "disabled") == 0) {
		return GB_HIGHPASS_OFF;
	}
	else if (g_strcmp0(config.high_pass_filter_id, "emulate_hardware") == 0) {
		return GB_HIGHPASS_ACCURATE;
	}
	else if (g_strcmp0(config.high_pass_filter_id, "preserve_waveform") == 0) {
		return GB_HIGHPASS_REMOVE_DC_OFFSET;
	}

	// This should not happen
	g_warning("Unknown highpass mode: %s\nFalling back to “Accurate”\n", config.high_pass_filter_id);
	default_value: return GB_HIGHPASS_ACCURATE;
}

void set_highpass_mode(GB_highpass_mode_t mode) {
	switch (mode) {
		case GB_HIGHPASS_OFF:
			config.high_pass_filter_id = "disabled";
			break;
		case GB_HIGHPASS_MAX:
			g_warning("GB_HIGHPASS_MAX is not a valid highpass mode, falling back to “Accurate”.\n");
		case GB_HIGHPASS_ACCURATE:
			config.high_pass_filter_id = "emulate_hardware";
			break;
		case GB_HIGHPASS_REMOVE_DC_OFFSET:
			config.high_pass_filter_id = "preserve_waveform";
			break;
	}
}