/*
 * Copyright (c) 2007-2014, Anthony Minessale II
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 
 * * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * * Neither the name of the original author; nor the names of any contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 * 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "blade.h"

typedef enum {
	BH_NONE = 0,
	BH_MYPOOL = (1 << 0),
	BH_MYTPOOL = (1 << 1)
} bhpvt_flag_t;

struct blade_handle_s {
	bhpvt_flag_t flags;
	ks_pool_t *pool;
	ks_thread_pool_t *tpool;
	
	config_setting_t *config_directory;
	config_setting_t *config_datastore;

	ks_hash_t *transports; // registered transports exposed by modules, NOT active connections

	//blade_identity_t *identity;
	blade_datastore_t *datastore;

	// @todo insert on connection creations, remove on connection destructions, key based on a UUID for the connection
	ks_hash_t *connections; // active connections keyed by connection id
	// @todo insert on session creations, remove on session destructions, key based on a UUID for the session
	ks_hash_t *sessions; // active sessions keyed by session id
	// @todo another hash with sessions keyed by the remote identity without parameters for quick lookup by target identity on sending?
	ks_hash_t *requests; // outgoing requests waiting for a response keyed by the message id
};


typedef struct blade_handle_transport_registration_s blade_handle_transport_registration_t;
struct blade_handle_transport_registration_s {
	ks_pool_t *pool;

	blade_module_t *module;
	blade_transport_callbacks_t *callbacks;
};

KS_DECLARE(ks_status_t) blade_handle_transport_registration_create(blade_handle_transport_registration_t **bhtrP,
																   ks_pool_t *pool,
																   blade_module_t *module,
																   blade_transport_callbacks_t *callbacks)
{
	blade_handle_transport_registration_t *bhtr = NULL;

	ks_assert(bhtrP);
	ks_assert(pool);
	ks_assert(module);
	ks_assert(callbacks);

	bhtr = ks_pool_alloc(pool, sizeof(blade_handle_transport_registration_t));
	bhtr->pool = pool;
	bhtr->module = module;
	bhtr->callbacks = callbacks;

	*bhtrP = bhtr;

	return KS_STATUS_SUCCESS;
}

KS_DECLARE(ks_status_t) blade_handle_transport_registration_destroy(blade_handle_transport_registration_t **bhtrP)
{
	blade_handle_transport_registration_t *bhtr = NULL;

	ks_assert(bhtrP);

	bhtr = *bhtrP;
	*bhtrP = NULL;

	ks_assert(bhtr);

	ks_pool_free(bhtr->pool, &bhtr);

	return KS_STATUS_SUCCESS;
}



KS_DECLARE(ks_status_t) blade_handle_create(blade_handle_t **bhP, ks_pool_t *pool, ks_thread_pool_t *tpool)
{
	bhpvt_flag_t newflags = BH_NONE;
	blade_handle_t *bh = NULL;

	ks_assert(bhP);

	if (!pool) {
		newflags |= BH_MYPOOL;
		ks_pool_open(&pool);
	}
    if (!tpool) {
		newflags |= BH_MYTPOOL;
		ks_thread_pool_create(&tpool, BLADE_HANDLE_TPOOL_MIN, BLADE_HANDLE_TPOOL_MAX, BLADE_HANDLE_TPOOL_STACK, KS_PRI_NORMAL, BLADE_HANDLE_TPOOL_IDLE);
		ks_assert(tpool);
	}
	
	bh = ks_pool_alloc(pool, sizeof(blade_handle_t));
	bh->flags = newflags;
	bh->pool = pool;
	bh->tpool = tpool;

	ks_hash_create(&bh->transports, KS_HASH_MODE_CASE_INSENSITIVE, KS_HASH_FLAG_NOLOCK | KS_HASH_FLAG_DUP_CHECK, bh->pool);
	ks_assert(bh->transports);
	
	ks_hash_create(&bh->connections, KS_HASH_MODE_CASE_INSENSITIVE, KS_HASH_FLAG_NOLOCK | KS_HASH_FLAG_DUP_CHECK, bh->pool);
	ks_assert(bh->connections);
	ks_hash_create(&bh->sessions, KS_HASH_MODE_CASE_INSENSITIVE, KS_HASH_FLAG_NOLOCK | KS_HASH_FLAG_DUP_CHECK, bh->pool);
	ks_assert(bh->sessions);
	// @todo decide if this is uint32_t or uuid string, prefer uuid string to avoid needing another lock and variable for next id
	ks_hash_create(&bh->requests, KS_HASH_MODE_CASE_INSENSITIVE, KS_HASH_FLAG_NOLOCK | KS_HASH_FLAG_DUP_CHECK, bh->pool);
	ks_assert(bh->requests);
	
	*bhP = bh;

	return KS_STATUS_SUCCESS;
}

KS_DECLARE(ks_status_t) blade_handle_destroy(blade_handle_t **bhP)
{
	blade_handle_t *bh = NULL;
	bhpvt_flag_t flags;
	ks_pool_t *pool;

	ks_assert(bhP);

	bh = *bhP;
	*bhP = NULL;

	ks_assert(bh);

	flags = bh->flags;
	pool = bh->pool;

	blade_handle_shutdown(bh);

	ks_hash_destroy(&bh->requests);
	ks_hash_destroy(&bh->sessions);
	ks_hash_destroy(&bh->connections);
	ks_hash_destroy(&bh->transports);

    if (bh->tpool && (flags & BH_MYTPOOL)) ks_thread_pool_destroy(&bh->tpool);

	ks_pool_free(bh->pool, &bh);

	if (pool && (flags & BH_MYPOOL)) {
		ks_pool_close(&pool);
	}

	return KS_STATUS_SUCCESS;
}

ks_status_t blade_handle_config(blade_handle_t *bh, config_setting_t *config)
{
	config_setting_t *directory = NULL;
	config_setting_t *datastore = NULL;
	
	ks_assert(bh);

	if (!config) return KS_STATUS_FAIL;
    if (!config_setting_is_group(config)) return KS_STATUS_FAIL;

	directory = config_setting_get_member(config, "directory");
	
    datastore = config_setting_get_member(config, "datastore");
    //if (datastore && !config_setting_is_group(datastore)) return KS_STATUS_FAIL;


	bh->config_directory = directory;
	bh->config_datastore = datastore;
	
	return KS_STATUS_SUCCESS;
}

KS_DECLARE(ks_status_t) blade_handle_startup(blade_handle_t *bh, config_setting_t *config)
{
	ks_assert(bh);

    if (blade_handle_config(bh, config) != KS_STATUS_SUCCESS) {
		ks_log(KS_LOG_DEBUG, "blade_handle_config failed\n");
		return KS_STATUS_FAIL;
	}

	if (bh->config_datastore && !blade_handle_datastore_available(bh)) {
		blade_datastore_create(&bh->datastore, bh->pool, bh->tpool);
		ks_assert(bh->datastore);
		if (blade_datastore_startup(bh->datastore, bh->config_datastore) != KS_STATUS_SUCCESS) {
			ks_log(KS_LOG_DEBUG, "blade_datastore_startup failed\n");
			return KS_STATUS_FAIL;
		}
	}

	// @todo load DSOs
	
	// @todo call onload and onstartup callbacks for modules from DSOs

	return KS_STATUS_SUCCESS;
}

KS_DECLARE(ks_status_t) blade_handle_shutdown(blade_handle_t *bh)
{
	ks_hash_iterator_t *it = NULL;

	ks_assert(bh);

	for (it = ks_hash_first(bh->requests, KS_UNLOCKED); it; it = ks_hash_next(&it)) {
		void *key = NULL;
		blade_request_t *value = NULL;
		
		ks_hash_this(it, (const void **)&key, NULL, (void **)&value);
		ks_hash_remove(bh->requests, key);
		
		blade_request_destroy(&value);
	}
	
	for (it = ks_hash_first(bh->sessions, KS_UNLOCKED); it; it = ks_hash_next(&it)) {
		void *key = NULL;
		blade_session_t *value = NULL;
		
		ks_hash_this(it, (const void **)&key, NULL, (void **)&value);
		ks_hash_remove(bh->requests, key);
		
		blade_session_hangup(value);
	}
	while (ks_hash_count(bh->sessions) > 0) ks_sleep_ms(100);

	// @todo call onshutdown and onunload callbacks for modules from DSOs, which will unregister transports and disconnect remaining unattached connections

	// @todo unload DSOs

	if (blade_handle_datastore_available(bh)) blade_datastore_destroy(&bh->datastore);

	return KS_STATUS_SUCCESS;
}

KS_DECLARE(ks_pool_t *) blade_handle_pool_get(blade_handle_t *bh)
{
	ks_assert(bh);
	return bh->pool;
}

KS_DECLARE(ks_thread_pool_t *) blade_handle_tpool_get(blade_handle_t *bh)
{
	ks_assert(bh);
	return bh->tpool;
}

KS_DECLARE(ks_status_t) blade_handle_transport_register(blade_handle_t *bh, blade_module_t *bm, const char *name, blade_transport_callbacks_t *callbacks)
{
	blade_handle_transport_registration_t *bhtr = NULL;
	blade_handle_transport_registration_t *bhtr_old = NULL;
	
	ks_assert(bh);
	ks_assert(bm);
	ks_assert(name);
	ks_assert(callbacks);

	// @todo reduce blade_handle_t parameter, pull from blade_module_t parameter

	blade_handle_transport_registration_create(&bhtr, bh->pool, bm, callbacks);
	ks_assert(bhtr);

	ks_hash_write_lock(bh->transports);
	bhtr_old = ks_hash_search(bh->transports, (void *)name, KS_UNLOCKED);
	if (bhtr_old) ks_hash_remove(bh->transports, (void *)name);
	ks_hash_insert(bh->transports, (void *)name, bhtr);
	ks_hash_write_unlock(bh->transports);

	if (bhtr_old) blade_handle_transport_registration_destroy(&bhtr_old);

	ks_log(KS_LOG_DEBUG, "Transport Registered: %s\n", name);

	return KS_STATUS_SUCCESS;
}

KS_DECLARE(ks_status_t) blade_handle_transport_unregister(blade_handle_t *bh, const char *name)
{
	blade_handle_transport_registration_t *bhtr = NULL;

	ks_assert(bh);
	ks_assert(name);

	ks_hash_write_lock(bh->transports);
	bhtr = ks_hash_search(bh->transports, (void *)name, KS_UNLOCKED);
	if (bhtr) ks_hash_remove(bh->transports, (void *)name);
	ks_hash_write_unlock(bh->transports);

	if (bhtr) blade_handle_transport_registration_destroy(&bhtr);

	return KS_STATUS_SUCCESS;
}

KS_DECLARE(ks_status_t) blade_handle_connect(blade_handle_t *bh, blade_connection_t **bcP, blade_identity_t *target, const char *session_id)
{
	ks_status_t ret = KS_STATUS_SUCCESS;
	blade_handle_transport_registration_t *bhtr = NULL;
	const char *tname = NULL;
	
	ks_assert(bh);
	ks_assert(target);

	// @todo this should take a callback, and push this to a queue to be processed async from another thread on the handle
	// which will allow the onconnect callback to block while doing things like DNS lookups without having unknown
	// impact depending on the caller thread

	ks_hash_read_lock(bh->transports);

	tname = blade_identity_parameter_get(target, "transport");
	if (tname) {
		bhtr = ks_hash_search(bh->transports, (void *)tname, KS_UNLOCKED);
		if (!bhtr) {
			// @todo error logging, target has an explicit transport that is not available in the local transports registry
			// discuss later whether this scenario should still attempt other transports when target is explicit
			// @note discussions indicate that by default messages should favor relaying through a master service, unless
			// an existing direct connection already exists to the target (which if the target is the master node, then there is
			// no conflict of proper routing). This also applies to routing for identities which relate to groups, relaying should
			// most often occur through a master service, however there may be scenarios that exist where an existing session
			// exists dedicated to faster delivery for a group (IE, through an ampq cluster directly, such as master services
			// syncing with each other through a pub/sub).  There is also the potential that instead of a separate session, the
			// current session with a master service may be able to have another connection attached which represents access through
			// amqp, which in turn acts as a preferred router for only group identities
			// This information does not directly apply to connecting, but should be noted for the next level up where you simply
			// send a message which will not actually connect, only check for existing sessions for the target and master service
			// @note relaying by master services should take a slightly different path, when they receive something not for the
			// master service itself, it should relay this on to all other master services, which in turn all including original
			// receiver pass on to any sessions matching an identity that is part of the group, alternatively they can use a pub/sub
			// like amqp to relay between the master services more efficiently than using the websocket to send every master service
			// session the message individually
		}
	} else {
		for (ks_hash_iterator_t *it = ks_hash_first(bh->transports, KS_UNLOCKED); it; it = ks_hash_next(&it)) {
			// @todo use onrank (or replace with whatever method is used for determining what transport to use) and keep highest ranked callbacks
		}
	}
	ks_hash_read_unlock(bh->transports);

	// @todo need to be able to get to the blade_module_t from the callbacks, may require envelope around registration of callbacks to include module
	// this is required because onconnect transport callback needs to be able to get back to the module data to create the connection being returned
	if (bhtr) ret = bhtr->callbacks->onconnect(bcP, bhtr->module, target, session_id);
	else ret = KS_STATUS_FAIL;

	return ret;
}


KS_DECLARE(blade_connection_t *) blade_handle_connections_get(blade_handle_t *bh, const char *cid)
{
	blade_connection_t *bc = NULL;

	ks_assert(bh);
	ks_assert(cid);

	ks_hash_read_lock(bh->connections);
	bc = ks_hash_search(bh->connections, (void *)cid, KS_UNLOCKED);
	if (bc && blade_connection_read_lock(bc, KS_FALSE) != KS_STATUS_SUCCESS) bc = NULL;
	ks_hash_read_unlock(bh->connections);

	return bc;
}

KS_DECLARE(ks_status_t) blade_handle_connections_add(blade_connection_t *bc)
{
	ks_status_t ret = KS_STATUS_SUCCESS;
	blade_handle_t *bh = NULL;

	ks_assert(bc);

	bh = blade_connection_handle_get(bc);
	ks_assert(bh);

	ks_hash_write_lock(bh->connections);
	ret = ks_hash_insert(bh->connections, (void *)blade_connection_id_get(bc), bc);
	ks_hash_write_unlock(bh->connections);

	return ret;
}

KS_DECLARE(ks_status_t) blade_handle_connections_remove(blade_connection_t *bc)
{
	ks_status_t ret = KS_STATUS_SUCCESS;
	blade_handle_t *bh = NULL;

	ks_assert(bc);

	bh = blade_connection_handle_get(bc);
	ks_assert(bh);

	blade_connection_write_lock(bc, KS_TRUE);

	ks_hash_write_lock(bh->connections);
	if (ks_hash_remove(bh->connections, (void *)blade_connection_id_get(bc)) == NULL) ret = KS_STATUS_FAIL;
	ks_hash_write_unlock(bh->connections);

	blade_connection_write_unlock(bc);

	return ret;
}


KS_DECLARE(blade_session_t *) blade_handle_sessions_get(blade_handle_t *bh, const char *sid)
{
	blade_session_t *bs = NULL;

	ks_assert(bh);
	ks_assert(sid);

	ks_hash_read_lock(bh->sessions);
	bs = ks_hash_search(bh->sessions, (void *)sid, KS_UNLOCKED);
	if (bs && blade_session_read_lock(bs, KS_FALSE) != KS_STATUS_SUCCESS) bs = NULL;
	ks_hash_read_unlock(bh->sessions);

	return bs;
}

KS_DECLARE(ks_status_t) blade_handle_sessions_add(blade_session_t *bs)
{
	ks_status_t ret = KS_STATUS_SUCCESS;
	blade_handle_t *bh = NULL;

	ks_assert(bs);

	bh = blade_session_handle_get(bs);
	ks_assert(bh);

	ks_hash_write_lock(bh->sessions);
	ret = ks_hash_insert(bh->sessions, (void *)blade_session_id_get(bs), bs);
	ks_hash_write_unlock(bh->sessions);

	return ret;
}

KS_DECLARE(ks_status_t) blade_handle_sessions_remove(blade_session_t *bs)
{
	ks_status_t ret = KS_STATUS_SUCCESS;
	blade_handle_t *bh = NULL;

	ks_assert(bs);

	bh = blade_session_handle_get(bs);
	ks_assert(bh);

	blade_session_write_lock(bs, KS_TRUE);

	ks_hash_write_lock(bh->sessions);
	if (ks_hash_remove(bh->sessions, (void *)blade_session_id_get(bs)) == NULL) ret = KS_STATUS_FAIL;
	ks_hash_write_unlock(bh->sessions);

	blade_session_write_unlock(bs);

	return ret;
}



KS_DECLARE(ks_bool_t) blade_handle_datastore_available(blade_handle_t *bh)
{
	ks_assert(bh);

	return bh->datastore != NULL;
}

KS_DECLARE(ks_status_t) blade_handle_datastore_store(blade_handle_t *bh, const void *key, int32_t key_length, const void *data, int64_t data_length)
{
	ks_assert(bh);
	ks_assert(key);
	ks_assert(key_length > 0);
	ks_assert(data);
	ks_assert(data_length > 0);

	if (!blade_handle_datastore_available(bh)) return KS_STATUS_INACTIVE;
	
	return blade_datastore_store(bh->datastore, key, key_length, data, data_length);
}

KS_DECLARE(ks_status_t) blade_handle_datastore_fetch(blade_handle_t *bh,
													 blade_datastore_fetch_callback_t callback,
													 const void *key,
													 int32_t key_length,
													 void *userdata)
{
	ks_assert(bh);
	ks_assert(callback);
	ks_assert(key);
	ks_assert(key_length > 0);
	
	if (!blade_handle_datastore_available(bh)) return KS_STATUS_INACTIVE;
	
	return blade_datastore_fetch(bh->datastore, callback, key, key_length, userdata);
}


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