/* PipeWire
 *
 * Copyright © 2020 Collabora Ltd.
 *   @author George Kiagiadakis <george.kiagiadakis@collabora.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#include <pipewire/impl.h>
#include <extensions/session-manager.h>
#include <spa/utils/result.h>

#define NAME "endpoint"

struct pw_proxy *pw_core_endpoint_export(struct pw_core *core,
		const char *type, const struct spa_dict *props, void *object,
		size_t user_data_size);

struct impl
{
	struct pw_global *global;
	struct spa_hook global_listener;

	union {
		struct pw_endpoint *endpoint;
		struct pw_resource *resource;
	};
	struct spa_hook resource_listener;
};

struct resource_data
{
	struct impl *impl;

	struct pw_resource *resource;
	struct spa_hook resource_listener;
	struct spa_hook object_listener;
	struct spa_hook endpoint_listener;
};

struct factory_data
{
	struct pw_impl_factory *this;

	struct pw_impl_module *module;
	struct spa_hook module_listener;

	struct pw_export_type export;
};

static int method_subscribe_params(void *object, uint32_t *ids, uint32_t n_ids)
{
	struct resource_data *d = object;
	struct impl *impl = d->impl;
	pw_endpoint_subscribe_params(impl->endpoint, ids, n_ids);
	return 0;
}

static int method_enum_params(void *object, int seq,
			uint32_t id, uint32_t start, uint32_t num,
			const struct spa_pod *filter)
{
	struct resource_data *d = object;
	struct impl *impl = d->impl;
	pw_endpoint_enum_params(impl->endpoint, seq, id, start, num, filter);
	return 0;
}

static int method_set_param(void *object, uint32_t id, uint32_t flags,
			  const struct spa_pod *param)
{
	struct resource_data *d = object;
	struct impl *impl = d->impl;
	pw_endpoint_set_param(impl->endpoint, id, flags, param);
	return 0;
}

static int method_create_link(void *object, const struct spa_dict *props)
{
	struct resource_data *d = object;
	struct impl *impl = d->impl;
	pw_endpoint_create_link(impl->endpoint, props);
	return 0;
}

static const struct pw_endpoint_methods endpoint_methods = {
	PW_VERSION_ENDPOINT_METHODS,
	.subscribe_params = method_subscribe_params,
	.enum_params = method_enum_params,
	.set_param = method_set_param,
	.create_link = method_create_link,
};

#define pw_endpoint_resource(r,m,v,...)      \
	pw_resource_call(r,struct pw_endpoint_events,m,v,__VA_ARGS__)

#define pw_endpoint_resource_info(r,...)        \
        pw_endpoint_resource(r,info,0,__VA_ARGS__)
#define pw_endpoint_resource_param(r,...)        \
        pw_endpoint_resource(r,param,0,__VA_ARGS__)

static void event_info(void *object, const struct pw_endpoint_info *info)
{
	struct resource_data *d = object;
	pw_endpoint_resource_info(d->resource, info);
}

static void event_param(void *object, int seq,
		       uint32_t id, uint32_t index, uint32_t next,
		       const struct spa_pod *param)
{
	struct resource_data *d = object;
	pw_endpoint_resource_param (d->resource, seq, id, index, next, param);
}

static const struct pw_endpoint_events endpoint_events = {
	PW_VERSION_ENDPOINT_EVENTS,
	.info = event_info,
	.param = event_param,
};

static void global_unbind(void *data)
{
	struct resource_data *d = data;
	if (d->resource)
		spa_hook_remove(&d->endpoint_listener);
}

static const struct pw_resource_events resource_events = {
	PW_VERSION_RESOURCE_EVENTS,
	.destroy = global_unbind,
};

static int global_bind(void *_data, struct pw_impl_client *client,
		uint32_t permissions, uint32_t version, uint32_t id)
{
	struct impl *impl = _data;
	struct pw_resource *resource;
	struct resource_data *data;

	resource = pw_resource_new(client, id, permissions,
				PW_TYPE_INTERFACE_Endpoint,
				version, sizeof(*data));
	if (resource == NULL)
		return -errno;

	data = pw_resource_get_user_data(resource);
	data->impl = impl;
	data->resource = resource;

	pw_global_add_resource(impl->global, resource);

	/* listen for when the resource goes away */
	pw_resource_add_listener(resource,
			&data->resource_listener,
			&resource_events, data);

	/* resource methods -> implemention */
	pw_resource_add_object_listener(resource,
			&data->object_listener,
			&endpoint_methods, data);
	/* implementation events -> resource */
	pw_endpoint_add_listener(impl->endpoint,
			&data->endpoint_listener,
			&endpoint_events, data);

	return 0;
}

static void global_destroy(void *data)
{
	struct impl *impl = data;
	spa_hook_remove(&impl->global_listener);
	impl->global = NULL;
	if (impl->resource)
		pw_resource_destroy(impl->resource);
}

static const struct pw_global_events global_events = {
	PW_VERSION_GLOBAL_EVENTS,
	.destroy = global_destroy,
};

static void global_resource_destroy(void *data)
{
	struct impl *impl = data;
	spa_hook_remove(&impl->resource_listener);
	impl->resource = NULL;
	if (impl->global)
		pw_global_destroy(impl->global);
}

static const struct pw_resource_events global_resource_events = {
	PW_VERSION_RESOURCE_EVENTS,
	.destroy = global_resource_destroy,
};

static void *endpoint_new(struct pw_context *context,
			  struct pw_resource *resource,
			  struct pw_properties *properties)
{
	struct impl *impl;

	impl = calloc(1, sizeof(*impl));
	if (impl == NULL) {
		pw_properties_free(properties);
		return NULL;
	}

	impl->global = pw_global_new(context,
			PW_TYPE_INTERFACE_Endpoint,
			PW_VERSION_ENDPOINT,
			properties,
			global_bind, impl);
	if (impl->global == NULL) {
		free(impl);
		return NULL;
	}
	impl->resource = resource;

	pw_global_add_listener(impl->global,
			&impl->global_listener,
			&global_events, impl);

	pw_resource_add_listener(resource,
			&impl->resource_listener,
			&global_resource_events, impl);

	pw_resource_set_bound_id(resource, pw_global_get_id (impl->global));
	pw_global_register(impl->global);

	return impl;
}

static void *create_object(void *data,
			   struct pw_resource *resource,
			   const char *type,
			   uint32_t version,
			   struct pw_properties *properties,
			   uint32_t new_id)
{
	struct factory_data *d = data;
	struct pw_resource *impl_resource;
	struct pw_impl_client *client = pw_resource_get_client(resource);
	void *result;
	int res;

	impl_resource = pw_resource_new(client, new_id, PW_PERM_RWX, type, version, 0);
	if (impl_resource == NULL) {
		res = -errno;
		goto error_resource;
	}

	pw_resource_install_marshal(impl_resource, true);

	if (properties == NULL)
		properties = pw_properties_new(NULL, NULL);
	if (properties == NULL) {
		res = -ENOMEM;
		goto error_endpoint;
	}

	pw_properties_setf(properties, PW_KEY_CLIENT_ID, "%d",
			pw_impl_client_get_info(client)->id);
	pw_properties_setf(properties, PW_KEY_FACTORY_ID, "%d",
			pw_impl_factory_get_info(d->this)->id);

	result = endpoint_new(pw_impl_client_get_context(client), impl_resource, properties);
	if (result == NULL) {
		res = -errno;
		goto error_endpoint;
	}
	return result;

error_resource:
	pw_log_error("can't create resource: %s", spa_strerror(res));
	pw_resource_errorf_id(resource, new_id, res, "can't create resource: %s", spa_strerror(res));
	goto error_exit;
error_endpoint:
	pw_log_error("can't create endpoint: %s", spa_strerror(res));
	pw_resource_errorf_id(resource, new_id, res, "can't create endpoint: %s", spa_strerror(res));
	goto error_exit_free;

error_exit_free:
	pw_resource_remove(impl_resource);
error_exit:
	errno = -res;
	return NULL;
}

static const struct pw_impl_factory_implementation impl_factory = {
	PW_VERSION_IMPL_FACTORY_IMPLEMENTATION,
	.create_object = create_object,
};

static void module_destroy(void *data)
{
	struct factory_data *d = data;

	spa_hook_remove(&d->module_listener);
	spa_list_remove(&d->export.link);
	pw_impl_factory_destroy(d->this);
}

static void module_registered(void *data)
{
	struct factory_data *d = data;
	struct pw_impl_module *module = d->module;
	struct pw_impl_factory *factory = d->this;
	struct spa_dict_item items[1];
	char id[16];
	int res;

	snprintf(id, sizeof(id), "%d", pw_impl_module_get_info(module)->id);
	items[0] = SPA_DICT_ITEM_INIT(PW_KEY_MODULE_ID, id);
	pw_impl_factory_update_properties(factory, &SPA_DICT_INIT(items, 1));

	if ((res = pw_impl_factory_register(factory, NULL)) < 0) {
		pw_log_error(NAME" %p: can't register factory: %s", factory, spa_strerror(res));
	}
}

static const struct pw_impl_module_events module_events = {
	PW_VERSION_IMPL_MODULE_EVENTS,
	.destroy = module_destroy,
	.registered = module_registered,
};

int endpoint_factory_init(struct pw_impl_module *module)
{
	struct pw_context *context = pw_impl_module_get_context(module);
	struct pw_impl_factory *factory;
	struct factory_data *data;

	factory = pw_context_create_factory(context,
				 "endpoint",
				 PW_TYPE_INTERFACE_Endpoint,
				 PW_VERSION_ENDPOINT,
				 NULL,
				 sizeof(*data));
	if (factory == NULL)
		return -errno;

	data = pw_impl_factory_get_user_data(factory);
	data->this = factory;
	data->module = module;

	pw_impl_factory_set_implementation(factory, &impl_factory, data);

	data->export.type = PW_TYPE_INTERFACE_Endpoint;
	data->export.func = pw_core_endpoint_export;
	pw_context_register_export_type(context, &data->export);

	pw_impl_module_add_listener(module, &data->module_listener, &module_events, data);

	return 0;
}