/* PipeWire
 *
 * Copyright © 2020 Wim Taymans
 *
 * 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.
 */

struct sample {
	int ref;
	uint32_t index;
	struct impl *impl;
	const char *name;
	struct sample_spec ss;
	struct channel_map map;
	struct pw_properties *props;
	uint32_t length;
	uint8_t *buffer;
};

struct sample_play_events {
#define VERSION_SAMPLE_PLAY_EVENTS	0
	uint32_t version;

	void (*ready) (void *data, uint32_t id);

	void (*error) (void *data, int err);

	void (*done) (void *data);
};

#define sample_play_emit_ready(p,i) spa_hook_list_call(&p->hooks, struct sample_play_events, ready, 0, i)
#define sample_play_emit_error(p,e) spa_hook_list_call(&p->hooks, struct sample_play_events, error, 0, e)
#define sample_play_emit_done(p) spa_hook_list_call(&p->hooks, struct sample_play_events, done, 0)

struct sample_play {
	struct spa_list link;
	struct sample *sample;
	struct pw_stream *stream;
	uint32_t index;
	struct spa_hook listener;
	struct pw_context *context;
	struct pw_loop *main_loop;
	uint32_t offset;
	uint32_t stride;
	struct spa_hook_list hooks;
	void *user_data;
};

static void sample_free(struct sample *sample);

static void sample_play_stream_state_changed(void *data, enum pw_stream_state old,
		enum pw_stream_state state, const char *error)
{
	struct sample_play *p = data;

	switch (state) {
	case PW_STREAM_STATE_UNCONNECTED:
	case PW_STREAM_STATE_ERROR:
		sample_play_emit_error(p, -EIO);
		break;
	case PW_STREAM_STATE_PAUSED:
		p->index = pw_stream_get_node_id(p->stream);
		sample_play_emit_ready(p, p->index);
		break;
	default:
		break;
	}
}

static void sample_play_stream_destroy(void *data)
{
	struct sample_play *p = data;

	pw_log_info("destroy %s", p->sample->name);
	spa_hook_remove(&p->listener);
	p->stream = NULL;
	if (--p->sample->ref == 0)
		sample_free(p->sample);
	p->sample = NULL;
}

static void sample_play_stream_process(void *data)
{
	struct sample_play *p = data;
	struct sample *s = p->sample;
	struct pw_buffer *b;
	struct spa_buffer *buf;
	uint32_t size;
	uint8_t *d;

	if (p->offset >= s->length) {
		pw_stream_flush(p->stream, true);
		return;
	}
	size = s->length - p->offset;

	if ((b = pw_stream_dequeue_buffer(p->stream)) == NULL) {
		pw_log_warn("out of buffers: %m");
                return;
	}

	buf = b->buffer;
	if ((d = buf->datas[0].data) == NULL)
		return;

	size = SPA_MIN(size, buf->datas[0].maxsize);

	memcpy(d, p->sample->buffer + p->offset, size);

	p->offset += size;

        buf->datas[0].chunk->offset = 0;
        buf->datas[0].chunk->stride = p->stride;
        buf->datas[0].chunk->size = size;

        pw_stream_queue_buffer(p->stream, b);
}

static void sample_play_stream_drained(void *data)
{
	struct sample_play *p = data;
	sample_play_emit_done(p);
}

struct pw_stream_events sample_play_stream_events = {
	PW_VERSION_STREAM_EVENTS,
	.state_changed = sample_play_stream_state_changed,
	.destroy = sample_play_stream_destroy,
	.process = sample_play_stream_process,
	.drained = sample_play_stream_drained,
};

static struct sample_play *sample_play_new(struct pw_core *core,
		struct sample *sample, struct pw_properties *props,
		size_t user_data_size)
{
	struct sample_play *p;
	uint8_t buffer[1024];
        struct spa_pod_builder b = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
	const struct spa_pod *params[1];
	uint32_t n_params = 0;
	int res;

	p = calloc(1, sizeof(struct sample_play) + user_data_size);
	if (p == NULL) {
		res = -errno;
		goto error_free;
	}

	p->context = pw_core_get_context(core);
	p->main_loop = pw_context_get_main_loop(p->context);
	spa_hook_list_init(&p->hooks);
	p->user_data = SPA_MEMBER(p, sizeof(struct sample_play), void);

	pw_properties_update(props, &sample->props->dict);

	p->stream = pw_stream_new(core, sample->name, props);
	props = NULL;
	if (p->stream == NULL) {
		res = -errno;
		goto error_free;
	}

	p->sample = sample;
	sample->ref++;

	pw_stream_add_listener(p->stream,
			&p->listener,
			&sample_play_stream_events, p);

	params[n_params++] = format_build_param(&b, SPA_PARAM_EnumFormat,
			&sample->ss, &sample->map);

	res = pw_stream_connect(p->stream,
			PW_DIRECTION_OUTPUT,
			PW_ID_ANY,
			PW_STREAM_FLAG_AUTOCONNECT |
			PW_STREAM_FLAG_MAP_BUFFERS |
			PW_STREAM_FLAG_RT_PROCESS,
			params, n_params);
	if (res < 0)
		goto error_cleanup;

	return p;

error_cleanup:
	pw_stream_destroy(p->stream);
error_free:
	if (props)
		pw_properties_free(props);
	free(p);
	errno = -res;
	return NULL;
}

static void sample_play_add_listener(struct sample_play *p,
		struct spa_hook *listener,
		const struct sample_play_events *events, void *data)
{
	spa_hook_list_append(&p->hooks, listener, events, data);
}

static void sample_play_destroy(struct sample_play *p)
{
	if (p->stream)
		pw_stream_destroy(p->stream);
	free(p);
}