/*
 * Copyright (c) 2013-2017, ARM Limited, All Rights Reserved
 * SPDX-License-Identifier: Apache-2.0
 *
 * 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.
 */

 #ifndef MBED_CONF_APP_CONNECT_STATEMENT
     #error [NOT_SUPPORTED] No network configuration found for this target.
 #endif

#ifndef MBED_EXTENDED_TESTS
    #error [NOT_SUPPORTED] Parallel tests are not supported by default
#endif

#include "mbed.h"
#include MBED_CONF_APP_HEADER_FILE
#include "UDPSocket.h"
#include "greentea-client/test_env.h"
#include "unity/unity.h"
#include "utest.h"

using namespace utest::v1;


#ifndef MBED_CFG_UDP_CLIENT_ECHO_BUFFER_SIZE
#define MBED_CFG_UDP_CLIENT_ECHO_BUFFER_SIZE 64
#endif

#ifndef MBED_CFG_UDP_CLIENT_ECHO_TIMEOUT
#define MBED_CFG_UDP_CLIENT_ECHO_TIMEOUT 500
#endif

#ifndef MBED_CFG_UDP_CLIENT_ECHO_THREADS
#define MBED_CFG_UDP_CLIENT_ECHO_THREADS 3
#endif

#define STRINGIZE(x) STRINGIZE2(x)
#define STRINGIZE2(x) #x


const int ECHO_LOOPS = 16;
NetworkInterface* net;
SocketAddress udp_addr;
Mutex iomutex;
char uuid[48] = {0};

// NOTE: assuming that "id" stays in the single digits
void prep_buffer(int id, char *uuid, char *tx_buffer, size_t tx_size) {
    size_t i = 0;

    tx_buffer[i++] = '0' + id;
    tx_buffer[i++] = ' ';

    memcpy(tx_buffer+i, uuid, strlen(uuid));
    i += strlen(uuid);

    tx_buffer[i++] = ' ';

    for (; i<tx_size; ++i) {
        tx_buffer[i] = (rand() % 10) + '0';
    }
}


// Each echo class is in charge of one parallel transaction
class Echo {
private:
    char tx_buffer[MBED_CFG_UDP_CLIENT_ECHO_BUFFER_SIZE];
    char rx_buffer[MBED_CFG_UDP_CLIENT_ECHO_BUFFER_SIZE];

    UDPSocket sock;
    Thread thread;
    bool result;
    int id;
    char *uuid;

public:
    // Limiting stack size to 1k
    Echo(): thread(osPriorityNormal, 1024), result(false) {
    }

    void start(int id, char *uuid) {
        this->id = id;
        this->uuid = uuid;
        osStatus status = thread.start(callback(this, &Echo::echo));
    }

    void join() {
        osStatus status = thread.join();
        TEST_ASSERT_EQUAL(osOK, status);
    }

    void echo() {
        int success = 0;

        int err = sock.open(net);
        TEST_ASSERT_EQUAL(0, err);

        sock.set_timeout(MBED_CFG_UDP_CLIENT_ECHO_TIMEOUT);

        for (int i = 0; success < ECHO_LOOPS; i++) {
            prep_buffer(id, uuid, tx_buffer, sizeof(tx_buffer));
            const int ret = sock.sendto(udp_addr, tx_buffer, sizeof(tx_buffer));
            if (ret >= 0) {
                iomutex.lock();
                printf("[ID:%01d][%02d] sent %d bytes - %.*s  \n", id, i, ret, ret, tx_buffer);
                iomutex.unlock();
            } else {
                iomutex.lock();
                printf("[ID:%01d][%02d] Network error %d\n", id, i, ret);
                iomutex.unlock();
                continue;
            }

            SocketAddress temp_addr;
            const int n = sock.recvfrom(&temp_addr, rx_buffer, sizeof(rx_buffer));
            if (n >= 0) {
                iomutex.lock();
                printf("[ID:%01d][%02d] recv %d bytes - %.*s  \n", id, i, n, n, tx_buffer);
                iomutex.unlock();
            } else {
                iomutex.lock();
                printf("[ID:%01d][%02d] Network error %d\n", id, i, n);
                iomutex.unlock();
                continue;
            }

            if ((temp_addr == udp_addr &&
                 n == sizeof(tx_buffer) &&
                 memcmp(rx_buffer, tx_buffer, sizeof(rx_buffer)) == 0)) {
                success += 1;
                iomutex.lock();
                printf("[ID:%01d][%02d] success #%d\n", id, i, success);
                iomutex.unlock();
                continue;
            }

            // failed, clean out any remaining bad packets
            sock.set_timeout(0);
            while (true) {
                err = sock.recvfrom(NULL, NULL, 0);
                if (err == NSAPI_ERROR_WOULD_BLOCK) {
                    break;
                }
            }
            sock.set_timeout(MBED_CFG_UDP_CLIENT_ECHO_TIMEOUT);
        }

        result = success == ECHO_LOOPS;

        err = sock.close();
        TEST_ASSERT_EQUAL(0, err);
        if (err) {
            result = false;
        }
    }

    bool get_result() {
        return result;
    }
};

Echo *echoers[MBED_CFG_UDP_CLIENT_ECHO_THREADS];


void test_udp_echo_parallel() {
    net = MBED_CONF_APP_OBJECT_CONSTRUCTION;
    int err =  MBED_CONF_APP_CONNECT_STATEMENT;
    TEST_ASSERT_EQUAL(0, err);

    if (err) {
        printf("MBED: failed to connect with an error of %d\r\n", err);
        GREENTEA_TESTSUITE_RESULT(false);
    } else {
        printf("UDP client IP Address is %s\n", net->get_ip_address());

        udp_addr.set_ip_address(MBED_CONF_APP_ECHO_SERVER_ADDR);
        udp_addr.set_port(MBED_CONF_APP_ECHO_SERVER_PORT);

        // Startup echo threads in parallel
        for (int i = 0; i < MBED_CFG_UDP_CLIENT_ECHO_THREADS; i++) {
            echoers[i] = new Echo;
            echoers[i]->start(i, uuid);
        }

        bool result = true;

        for (int i = 0; i < MBED_CFG_UDP_CLIENT_ECHO_THREADS; i++) {
            echoers[i]->join();
            result = result && echoers[i]->get_result();
            delete echoers[i];
        }

        net->disconnect();
        TEST_ASSERT_EQUAL(true, result);
    }
}


// Test setup
utest::v1::status_t test_setup(const size_t number_of_cases) {
    GREENTEA_SETUP(120, "udp_echo");
    return verbose_test_setup_handler(number_of_cases);
}

Case cases[] = {
    Case("UDP echo parallel", test_udp_echo_parallel),
};

Specification specification(test_setup, cases);

int main() {
    return !Harness::run(specification);
}