/*
 * Lab-Project-coreMQTT-Agent 201215
 * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
 *
 * 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 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.
 *
 * http://www.FreeRTOS.org
 * http://aws.amazon.com/freertos
 *
 * 1 tab == 4 spaces!
 */

/***
 * See https://www.FreeRTOS.org/mqtt/mqtt-agent-demo.html for configuration and usage
 * instructions.
 ***/

/* Standard includes. */
#include <stdio.h>
#include <time.h>

/* FreeRTOS includes. */
#include <FreeRTOS.h>
#include "task.h"

/* TCP/IP stack includes. */
#include "FreeRTOS_IP.h"
#include "FreeRTOS_Sockets.h"

/* Demo Specific configs. */
#include "demo_config.h"

/*
 * Prototypes for the demos that can be started from this project.  Note the
 * MQTT demo is not actually started until the network is already, which is
 * indicated by vApplicationIPNetworkEventHook() executing - hence
 * prvStartMQTTAgentDemo() is called from inside vApplicationIPNetworkEventHook().
 */
extern void vStartMQTTAgentDemo( void );

/*
 * Just seeds the simple pseudo random number generator.
 *
 * !!! NOTE !!!
 * This is not a secure method of generating random numbers and production
 * devices should use a true random number generator (TRNG).
 */
static void prvSRand( UBaseType_t ulSeed );

/*
 * Miscellaneous initialization including preparing the logging and seeding the
 * random number generator.
 */
static void prvMiscInitialisation( void );

/* The default IP and MAC address used by the demo.  The address configuration
 * defined here will be used if ipconfigUSE_DHCP is 0, or if ipconfigUSE_DHCP is
 * 1 but a DHCP server could not be contacted.  See the online documentation for
 * more information. */
static const uint8_t ucIPAddress[ 4 ] = { configIP_ADDR0, configIP_ADDR1, configIP_ADDR2, configIP_ADDR3 };
static const uint8_t ucNetMask[ 4 ] = { configNET_MASK0, configNET_MASK1, configNET_MASK2, configNET_MASK3 };
static const uint8_t ucGatewayAddress[ 4 ] = { configGATEWAY_ADDR0, configGATEWAY_ADDR1, configGATEWAY_ADDR2, configGATEWAY_ADDR3 };
static const uint8_t ucDNSServerAddress[ 4 ] = { configDNS_SERVER_ADDR0, configDNS_SERVER_ADDR1, configDNS_SERVER_ADDR2, configDNS_SERVER_ADDR3 };


/* Default MAC address configuration.  The demo creates a virtual network
 * connection that uses this MAC address by accessing the raw Ethernet data
 * to and from a real network connection on the host PC.  See the
 * configNETWORK_INTERFACE_TO_USE definition for information on how to configure
 * the real network connection to use. */
const uint8_t ucMACAddress[ 6 ] = { configMAC_ADDR0, configMAC_ADDR1, configMAC_ADDR2, configMAC_ADDR3, configMAC_ADDR4, configMAC_ADDR5 };

/* Use by the pseudo random number generator. */
static UBaseType_t ulNextRand;

/*-----------------------------------------------------------*/

int main( void )
{
    /***
     * See https://www.FreeRTOS.org/mqtt and https://www.FreeRTOS.org/tcp for
     * configuration and usage instructions.
     ***/

    /* Miscellaneous initialization including preparing the logging and seeding
     * the random number generator. */
    prvMiscInitialisation();

    /* Initialize the network interface.
     *
     ***NOTE*** Tasks that use the network are created in the network event hook
     * when the network is connected and ready for use (see the implementation of
     * vApplicationIPNetworkEventHook() below).  The address values passed in here
     * are used if ipconfigUSE_DHCP is set to 0, or if ipconfigUSE_DHCP is set to 1
     * but a DHCP server cannot be contacted. */
    FreeRTOS_IPInit( ucIPAddress, ucNetMask, ucGatewayAddress, ucDNSServerAddress, ucMACAddress );

    /* Start the RTOS scheduler. */
    vTaskStartScheduler();

    /* If all is well, the scheduler will now be running, and the following
     * line will never be reached.  If the following line does execute, then
     * there was insufficient FreeRTOS heap memory available for the idle and/or
     * timer tasks to be created.  See the memory management section on the
     * FreeRTOS web site for more details (this is standard text that is not
     * really applicable to the Win32 simulator port). */
    for( ; ; )
    {
    }
}
/*-----------------------------------------------------------*/

/* Called by FreeRTOS+TCP when the network connects or disconnects.  Disconnect
 * events are only received if implemented in the MAC driver. */
void vApplicationIPNetworkEventHook( eIPCallbackEvent_t eNetworkEvent )
{
    uint32_t ulIPAddress, ulNetMask, ulGatewayAddress, ulDNSServerAddress;
    char cBuffer[ 16 ];
    static BaseType_t xTasksAlreadyCreated = pdFALSE;

    /* If the network has just come up...*/
    if( eNetworkEvent == eNetworkUp )
    {
        /* Create the tasks that use the IP stack if they have not already been
         * created. */
        if( xTasksAlreadyCreated == pdFALSE )
        {
            /* Demos that use the network are created after the network is
             * up. */
            LogInfo( ( "---------STARTING DEMO---------\r\n" ) );
            vStartMQTTAgentDemo();
            xTasksAlreadyCreated = pdTRUE;
        }

        /* Print out the network configuration, which may have come from a DHCP
         * server. */
        FreeRTOS_GetAddressConfiguration( &ulIPAddress, &ulNetMask, &ulGatewayAddress, &ulDNSServerAddress );
        FreeRTOS_inet_ntoa( ulIPAddress, cBuffer );
        LogInfo( ( "\r\n\r\nIP Address: %s\r\n", cBuffer ) );

        FreeRTOS_inet_ntoa( ulNetMask, cBuffer );
        LogInfo( ( "Subnet Mask: %s\r\n", cBuffer ) );

        FreeRTOS_inet_ntoa( ulGatewayAddress, cBuffer );
        LogInfo( ( "Gateway Address: %s\r\n", cBuffer ) );

        FreeRTOS_inet_ntoa( ulDNSServerAddress, cBuffer );
        LogInfo( ( "DNS Server Address: %s\r\n\r\n\r\n", cBuffer ) );
    }
}
/*-----------------------------------------------------------*/

void vAssertCalled( const char * pcFile,
                    uint32_t ulLine )
{
    volatile uint32_t ulBlockVariable = 0UL;
    volatile char * pcFileName = ( volatile char * ) pcFile;
    volatile uint32_t ulLineNumber = ulLine;

    ( void ) pcFileName;
    ( void ) ulLineNumber;

    LogError( ( "vAssertCalled( %s, %u\n", pcFile, ( unsigned int ) ulLine ) );

    /* Setting ulBlockVariable to a non-zero value in the debugger will allow
     * this function to be exited. */
    taskDISABLE_INTERRUPTS();
    {
        while( ulBlockVariable == 0UL )
        {
        }
    }
    taskENABLE_INTERRUPTS();
}
/*-----------------------------------------------------------*/

UBaseType_t uxRand( void )
{
    const uint32_t ulMultiplier = 0x015a4e35UL, ulIncrement = 1UL;

    /*
     * Utility function to generate a pseudo random number.
     *
     * !!!NOTE!!!
     * This is not a secure method of generating a random number.  Production
     * devices should use a True Random Number Generator (TRNG).
     */
    ulNextRand = ( ulMultiplier * ulNextRand ) + ulIncrement;
    return ulNextRand;
}
/*-----------------------------------------------------------*/

static void prvSRand( UBaseType_t ulSeed )
{
    /* Utility function to seed the pseudo random number generator. */
    ulNextRand = ulSeed;
}
/*-----------------------------------------------------------*/

static void prvMiscInitialisation( void )
{
    time_t xTimeNow;

    /* Perform any initialization that is specific to a build.  This macro
     * can be defined in the build specific FreeRTOSConfig.h header file. */
    #ifdef configBUILD_SPECIFIC_INITIALISATION
        {
            configBUILD_SPECIFIC_INITIALISATION();
        }
    #endif

    vLoggingInit();

    /*
     * Seed random number generator.
     *
     * !!!NOTE!!!
     * This is not a secure method of generating a random number.  Production
     * devices should use a True Random Number Generator (TRNG).
     */
    time( &xTimeNow );
    LogDebug( ( "Seed for randomizer: %lu\n", xTimeNow ) );
    prvSRand( ( uint32_t ) xTimeNow );
    LogDebug( ( "Random numbers: %08X %08X %08X %08X\n", ipconfigRAND32(), ipconfigRAND32(), ipconfigRAND32(), ipconfigRAND32() ) );
}
/*-----------------------------------------------------------*/

/*
 * Callback that provides the inputs necessary to generate a randomized TCP
 * Initial Sequence Number per RFC 6528.  THIS IS ONLY A DUMMY IMPLEMENTATION
 * THAT RETURNS A PSEUDO RANDOM NUMBER SO IS NOT INTENDED FOR USE IN PRODUCTION
 * SYSTEMS.
 */
extern uint32_t ulApplicationGetNextSequenceNumber( uint32_t ulSourceAddress,
                                                    uint16_t usSourcePort,
                                                    uint32_t ulDestinationAddress,
                                                    uint16_t usDestinationPort )
{
    ( void ) ulSourceAddress;
    ( void ) usSourcePort;
    ( void ) ulDestinationAddress;
    ( void ) usDestinationPort;

    return uxRand();
}
/*-----------------------------------------------------------*/

/*
 * Set *pulNumber to a random number, and return pdTRUE. When the random number
 * generator is broken, it shall return pdFALSE.
 * The macros ipconfigRAND32() and configRAND32() are not in use
 * anymore in FreeRTOS+TCP.
 *
 * THIS IS ONLY A DUMMY IMPLEMENTATION THAT RETURNS A PSEUDO RANDOM NUMBER SO IS
 * NOT INTENDED FOR USE IN PRODUCTION SYSTEMS.
 */
BaseType_t xApplicationGetRandomNumber( uint32_t * pulNumber )
{
    *pulNumber = uxRand();
    return pdTRUE;
}
/*-----------------------------------------------------------*/

/* configUSE_STATIC_ALLOCATION is set to 1, so the application must provide an
 * implementation of vApplicationGetIdleTaskMemory() to provide the memory that is
 * used by the Idle task. */
void vApplicationGetIdleTaskMemory( StaticTask_t ** ppxIdleTaskTCBBuffer,
                                    StackType_t ** ppxIdleTaskStackBuffer,
                                    uint32_t * pulIdleTaskStackSize )
{
    /* If the buffers to be provided to the Idle task are declared inside this
     * function then they must be declared static - otherwise they will be allocated on
     * the stack and so not exists after this function exits. */
    static StaticTask_t xIdleTaskTCB;
    static StackType_t uxIdleTaskStack[ configMINIMAL_STACK_SIZE ];

    /* Pass out a pointer to the StaticTask_t structure in which the Idle task's
     * state will be stored. */
    *ppxIdleTaskTCBBuffer = &xIdleTaskTCB;

    /* Pass out the array that will be used as the Idle task's stack. */
    *ppxIdleTaskStackBuffer = uxIdleTaskStack;

    /* Pass out the size of the array pointed to by *ppxIdleTaskStackBuffer.
     * Note that, as the array is necessarily of type StackType_t,
     * configMINIMAL_STACK_SIZE is specified in words, not bytes. */
    *pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;
}
/*-----------------------------------------------------------*/

/* configUSE_STATIC_ALLOCATION and configUSE_TIMERS are both set to 1, so the
 * application must provide an implementation of vApplicationGetTimerTaskMemory()
 * to provide the memory that is used by the Timer service task. */
void vApplicationGetTimerTaskMemory( StaticTask_t ** ppxTimerTaskTCBBuffer,
                                     StackType_t ** ppxTimerTaskStackBuffer,
                                     uint32_t * pulTimerTaskStackSize )
{
    /* If the buffers to be provided to the Timer task are declared inside this
     * function then they must be declared static - otherwise they will be allocated on
     * the stack and so not exists after this function exits. */
    static StaticTask_t xTimerTaskTCB;
    static StackType_t uxTimerTaskStack[ configTIMER_TASK_STACK_DEPTH ];

    /* Pass out a pointer to the StaticTask_t structure in which the Timer
     * task's state will be stored. */
    *ppxTimerTaskTCBBuffer = &xTimerTaskTCB;

    /* Pass out the array that will be used as the Timer task's stack. */
    *ppxTimerTaskStackBuffer = uxTimerTaskStack;

    /* Pass out the size of the array pointed to by *ppxTimerTaskStackBuffer.
     * Note that, as the array is necessarily of type StackType_t,
     * configMINIMAL_STACK_SIZE is specified in words, not bytes. */
    *pulTimerTaskStackSize = configTIMER_TASK_STACK_DEPTH;
}
/*-----------------------------------------------------------*/

void vApplicationMallocFailedHook( void )
{
    LogDebug( ( "Malloc failed\n" ) );
}
/*-----------------------------------------------------------*/

void vApplicationStackOverflowHook( TaskHandle_t xTask,
                                    char * pcTaskName )

{
    volatile uint32_t ulSetToZeroToStepOut = 1UL;

    LogDebug( ( "Stack overflow in %s\n", pcTaskName ) );
    ( void ) xTask;
    ( void ) pcTaskName; /* Remove compiler warnings if LogDebug() is not defined. */

    taskENTER_CRITICAL();

    while( ulSetToZeroToStepOut != 0 )
    {
    }

    taskEXIT_CRITICAL();
}