/*
    Copyright (c) 2020 Intel Corporation

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/


#include "common/test.h"

#include "common/utils.h"
#include "common/graph_utils.h"

#include "oneapi/tbb/flow_graph.h"
#include "oneapi/tbb/task_arena.h"
#include "oneapi/tbb/global_control.h"

#include "conformance_flowgraph.h"

//! \file conformance_write_once_node.cpp
//! \brief Test for [flow_graph.write_once_node] specification

/*
TODO: implement missing conformance tests for write_once_node:
  - [ ] The copy constructor and copy assignment are called for the node's type template parameter.
  - [ ] Improve copy constructor and general constructor tests.
  - [ ] Write test checking the value is initially invalid.
  - [ ] Write test checking that the gets from the node are non-destructive, but the first `try_get'
    fails.
  - [ ] Add test on `write_once_node::is_valid()' method.
  - [ ] Add test on `write_once_node::clear()' method.
  - [ ] Add test with reserving `join_node' as node's successor. Use example from the spec.
*/

template<typename T>
void test_inheritance(){
    using namespace oneapi::tbb::flow;

    CHECK_MESSAGE( (std::is_base_of<graph_node, write_once_node<T>>::value), "write_once_node should be derived from graph_node");
    CHECK_MESSAGE( (std::is_base_of<receiver<T>, write_once_node<T>>::value), "write_once_node should be derived from receiver<T>");
    CHECK_MESSAGE( (std::is_base_of<sender<T>, write_once_node<T>>::value), "write_once_node should be derived from sender<T>");
}

void test_copies(){
    using namespace oneapi::tbb::flow;

    graph g;
    write_once_node<int> fn(g);
    write_once_node<int> fn2(fn);

}
void test_buffering(){
    oneapi::tbb::flow::graph g;

    oneapi::tbb::flow::write_once_node<int> node(g);
    oneapi::tbb::flow::limiter_node<int> rejecter(g, 0);

    oneapi::tbb::flow::make_edge(node, rejecter);
    node.try_put(1);

    int tmp = -1;
    CHECK_MESSAGE( (node.try_get(tmp) == true), "try_get after rejection should succeed");
    CHECK_MESSAGE( (tmp == 1), "try_get after rejection should set value");
    g.wait_for_all();
}

void test_forwarding(){
    oneapi::tbb::flow::graph g;

    oneapi::tbb::flow::write_once_node<int> node1(g);
    test_push_receiver<int> node2(g);
    test_push_receiver<int> node3(g);

    oneapi::tbb::flow::make_edge(node1, node2);
    oneapi::tbb::flow::make_edge(node1, node3);

    node1.try_put(1);
    g.wait_for_all();

    CHECK_MESSAGE( (get_count(node2) == 1), "Descendant of the node must receive one message.");
    CHECK_MESSAGE( (get_count(node3) == 1), "Descendant of the node must receive one message.");
}


void test_writing_once(){
    oneapi::tbb::flow::graph g;

    oneapi::tbb::flow::write_once_node<int> node1(g);

    int tmp = -1;
    node1.try_put(1);

    CHECK_MESSAGE( (node1.try_get(tmp) == true), "Descendant needs to receive");
    CHECK_MESSAGE( (tmp == 1), "Descendant needs be receive correct message");

    CHECK_MESSAGE( (node1.try_put(2) == false), "Putting again should not succeed");

    CHECK_MESSAGE( (node1.try_get(tmp) == true), "try_get should still succeed");
    CHECK_MESSAGE( (tmp == 1), "try_get should receive initial value");

    g.wait_for_all();
}

//! Test overwrite_node behavior
//! \brief \ref requirement
TEST_CASE("write_once_node messages"){
    test_writing_once();
}

//! Test function_node broadcast
//! \brief \ref requirement
TEST_CASE("overwrite_node broadcast"){
    test_forwarding();
}

//! Test write_once_node buffering
//! \brief \ref requirement
TEST_CASE("write_once_node buffering"){
    test_buffering();
}

//! Test copy constructor
//! \brief \ref interface
TEST_CASE("write_once_node copy constructor"){
    test_copies();
}

//! Test inheritance relations
//! \brief \ref interface
TEST_CASE("write_once_node superclasses"){
    test_inheritance<int>();
    test_inheritance<void*>();
}