/*
 * FreeRTOS V202212.00
 * 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.
 *
 * https://www.FreeRTOS.org
 * https://github.com/FreeRTOS
 *
 */

/*
 * Creates all the demo application tasks, then starts the scheduler.
 *
 * Main. c also creates a task called "Print".  This only executes every five
 * seconds but has the highest priority so is guaranteed to get processor time.
 * Its main function is to check that all the other tasks are still operational.
 * Nearly all the tasks in the demo application maintain a unique count that is
 * incremented each time the task successfully completes its function.  Should any
 * error occur within the task the count is permanently halted.  The print task
 * checks the count of each task to ensure it has changed since the last time the
 * print task executed.  If any count is found not to have changed the print task
 * displays an appropriate message, halts, and flashes the on board LED rapidly.
 * If all the tasks are still incrementing their unique counts the print task
 * displays an "OK" message.
 *
 * The LED flash tasks do not maintain a count as they already provide visual
 * feedback of their status.
 *
 * The print task blocks on the queue into which messages that require displaying
 * are posted.  It will therefore only block for the full 5 seconds if no messages
 * are posted onto the queue.
 *
 * Main. c also provides a demonstration of how the trace visualisation utility can
 * be used, and how the scheduler can be stopped.
 *
 * On the Flashlite it is preferable not to try to write to the console during
 * real time operation.  The built in LED is toggled every cycle of the print task
 * that does not encounter any errors, so the console IO may be removed if required.
 * The build in LED will start flashing rapidly if any task reports an error.
 */

/*
 * Changes from V1.01:
 *
 + Previously, if an error occurred in a task the on board LED was stopped from
 +    toggling.  Now if an error occurs the check task enters an infinite loop,
 +    toggling the LED rapidly.
 +
 + Changes from V1.2.3
 +
 + The integer and comtest tasks are now used when the cooperative scheduler
 +    is being used.  Previously they were only used with the preemptive
 +    scheduler.
 +
 + Changes from V1.2.5
 +
 + Made the communications RX task a higher priority.
 +
 + Changes from V2.0.0
 +
 + Delay periods are now specified using variables and constants of
 +    TickType_t rather than unsigned long.
 */

#include <stdlib.h>
#include <conio.h>
#include "FreeRTOS.h"
#include "task.h"
#include "partest.h"
#include "serial.h"

/* Demo file headers. */
#include "BlockQ.h"
#include "PollQ.h"
#include "death.h"
#include "flash.h"
#include "integer.h"
#include "print.h"
#include "comtest.h"
#include "fileio.h"
#include "semtest.h"

/* Priority definitions for all the tasks in the demo application. */
#define mainLED_TASK_PRIORITY          ( tskIDLE_PRIORITY + 1 )
#define mainCREATOR_TASK_PRIORITY      ( tskIDLE_PRIORITY + 3 )
#define mainPRINT_TASK_PRIORITY        ( tskIDLE_PRIORITY + 5 )
#define mainQUEUE_POLL_PRIORITY        ( tskIDLE_PRIORITY + 2 )
#define mainQUEUE_BLOCK_PRIORITY       ( tskIDLE_PRIORITY + 3 )
#define mainCOM_TEST_PRIORITY          ( tskIDLE_PRIORITY + 3 )
#define mainSEMAPHORE_TASK_PRIORITY    ( tskIDLE_PRIORITY + 1 )

#define mainPRINT_STACK_SIZE           ( ( unsigned short ) 256 )
#define mainDEBUG_LOG_BUFFER_SIZE      ( ( unsigned short ) 20480 )

/* Constant definitions for accessing the build in LED on the Flashlite 186. */
#define mainLED_REG_DIR                ( ( unsigned short ) 0xff78 )
#define mainLED_REG                    ( ( unsigned short ) 0xff7a )

/* If an error is detected in a task then the vErrorChecks() task will enter
 * an infinite loop flashing the LED at this rate. */
#define mainERROR_FLASH_RATE           ( ( TickType_t ) 100 / portTICK_PERIOD_MS )

/* Task function for the "Print" task as described at the top of the file. */
static void vErrorChecks( void * pvParameters );

/* Function that checks the unique count of all the other tasks as described at
 * the top of the file. */
static void prvCheckOtherTasksAreStillRunning( void );

/* Functions to setup and use the built in LED on the Flashlite 186 board. */
static void prvToggleLED( void );
static void prvInitLED( void );

/* Key presses can be used to start/stop the trace visualisation utility or stop
 * the scheduler. */
static void prvCheckForKeyPresses( void );

/* Buffer used by the trace visualisation utility. */
static char pcWriteBuffer[ mainDEBUG_LOG_BUFFER_SIZE ];

/*-----------------------------------------------------------*/
short main( void )
{
    /* Initialise hardware and utilities. */
    vParTestInitialise();
    vPrintInitialise();
    prvInitLED();

    /* CREATE ALL THE DEMO APPLICATION TASKS. */

    vStartComTestTasks( mainCOM_TEST_PRIORITY, serCOM2, ser38400 );
    vStartIntegerMathTasks( tskIDLE_PRIORITY );
    vStartPolledQueueTasks( mainQUEUE_POLL_PRIORITY );
    vStartBlockingQueueTasks( mainQUEUE_BLOCK_PRIORITY );
    vStartLEDFlashTasks( mainLED_TASK_PRIORITY );
    vStartSemaphoreTasks( mainSEMAPHORE_TASK_PRIORITY );

    /* Create the "Print" task as described at the top of the file. */
    xTaskCreate( vErrorChecks, "Print", mainPRINT_STACK_SIZE, NULL, mainPRINT_TASK_PRIORITY, NULL );

    /* This task has to be created last as it keeps account of the number of tasks
     * it expects to see running. */
    vCreateSuicidalTasks( mainCREATOR_TASK_PRIORITY );

    /* Set the scheduler running.  This function will not return unless a task
     * calls vTaskEndScheduler(). */
    vTaskStartScheduler();

    return 1;
}
/*-----------------------------------------------------------*/

static void vErrorChecks( void * pvParameters )
{
    TickType_t xExpectedWakeTime;
    const TickType_t xPrintRate = ( TickType_t ) 5000 / portTICK_PERIOD_MS;
    const long lMaxAllowableTimeDifference = ( long ) 0;
    TickType_t xWakeTime;
    long lTimeDifference;
    const char * pcReceivedMessage;
    const char * const pcTaskBlockedTooLongMsg = "Print task blocked too long!\r\n";

    /* Stop warnings. */
    ( void ) pvParameters;

    /* Loop continuously, blocking, then checking all the other tasks are still
     * running, before blocking once again.  This task blocks on the queue of messages
     * that require displaying so will wake either by its time out expiring, or a
     * message becoming available. */
    for( ; ; )
    {
        /* Calculate the time we will unblock if no messages are received
         * on the queue.  This is used to check that we have not blocked for too long. */
        xExpectedWakeTime = xTaskGetTickCount();
        xExpectedWakeTime += xPrintRate;

        /* Block waiting for either a time out or a message to be posted that
         * required displaying. */
        pcReceivedMessage = pcPrintGetNextMessage( xPrintRate );

        /* Was a message received? */
        if( pcReceivedMessage == NULL )
        {
            /* A message was not received so we timed out, did we unblock at the
             * expected time? */
            xWakeTime = xTaskGetTickCount();

            /* Calculate the difference between the time we unblocked and the
             * time we should have unblocked. */
            if( xWakeTime > xExpectedWakeTime )
            {
                lTimeDifference = ( long ) ( xWakeTime - xExpectedWakeTime );
            }
            else
            {
                lTimeDifference = ( long ) ( xExpectedWakeTime - xWakeTime );
            }

            if( lTimeDifference > lMaxAllowableTimeDifference )
            {
                /* We blocked too long - create a message that will get
                 * printed out the next time around. */
                vPrintDisplayMessage( &pcTaskBlockedTooLongMsg );
            }

            /* Check the other tasks are still running, just in case. */
            prvCheckOtherTasksAreStillRunning();
        }
        else
        {
            /* We unblocked due to a message becoming available.  Send the message
             * for printing. */
            vDisplayMessage( pcReceivedMessage );
        }

        /* Key presses are used to invoke the trace visualisation utility, or
         * end the program. */
        prvCheckForKeyPresses();
    }
} /*lint !e715 !e818 pvParameters is not used but all task functions must take this form. */
/*-----------------------------------------------------------*/

static void prvCheckForKeyPresses( void )
{
    #ifdef USE_STDIO
        short sIn;


        taskENTER_CRITICAL();
        sIn = kbhit();
        taskEXIT_CRITICAL();

        if( sIn )
        {
            unsigned long ulBufferLength;

            /* Key presses can be used to start/stop the trace utility, or end the
             * program. */
            sIn = getch();

            switch( sIn )
            {
                /* Only define keys for turning on and off the trace if the trace
                 * is being used. */
                #if configUSE_TRACE_FACILITY == 1
                    case 't':
                        vTaskList( pcWriteBuffer );
                        vWriteMessageToDisk( pcWriteBuffer );
                        break;

                        /* The legacy trace is no longer supported.  Use FreeRTOS+Trace instead.
                         * case 's' :	vTaskStartTrace( pcWriteBuffer, mainDEBUG_LOG_BUFFER_SIZE );
                         *          break;
                         *
                         * case 'e' :	ulBufferLength = ulTaskEndTrace();
                         *          vWriteBufferToDisk( pcWriteBuffer, ulBufferLength );
                         *          break;*/
                #endif

                default:
                    vTaskEndScheduler();
                    break;
            }
        }
    #else /* ifdef USE_STDIO */
        ( void ) pcWriteBuffer;
    #endif /* ifdef USE_STDIO */
}
/*-----------------------------------------------------------*/

static void prvCheckOtherTasksAreStillRunning( void )
{
    short sErrorHasOccurred = pdFALSE;

    if( xAreComTestTasksStillRunning() != pdTRUE )
    {
        vDisplayMessage( "Com test count unchanged!\r\n" );
        sErrorHasOccurred = pdTRUE;
    }

    if( xAreIntegerMathsTaskStillRunning() != pdTRUE )
    {
        vDisplayMessage( "Integer maths task count unchanged!\r\n" );
        sErrorHasOccurred = pdTRUE;
    }

    if( xAreBlockingQueuesStillRunning() != pdTRUE )
    {
        vDisplayMessage( "Blocking queues count unchanged!\r\n" );
        sErrorHasOccurred = pdTRUE;
    }

    if( xArePollingQueuesStillRunning() != pdTRUE )
    {
        vDisplayMessage( "Polling queue count unchanged!\r\n" );
        sErrorHasOccurred = pdTRUE;
    }

    if( xIsCreateTaskStillRunning() != pdTRUE )
    {
        vDisplayMessage( "Incorrect number of tasks running!\r\n" );
        sErrorHasOccurred = pdTRUE;
    }

    if( xAreSemaphoreTasksStillRunning() != pdTRUE )
    {
        vDisplayMessage( "Semaphore take count unchanged!\r\n" );
        sErrorHasOccurred = pdTRUE;
    }

    if( sErrorHasOccurred == pdFALSE )
    {
        vDisplayMessage( "OK " );

        /* Toggle the LED if everything is okay so we know if an error occurs even if not
         * using console IO. */
        prvToggleLED();
    }
    else
    {
        for( ; ; )
        {
            /* An error has occurred in one of the tasks.  Don't go any further and
             * flash the LED rapidly in case console IO is not being used. */
            prvToggleLED();
            vTaskDelay( mainERROR_FLASH_RATE );
        }
    }
}
/*-----------------------------------------------------------*/

static void prvInitLED( void )
{
    unsigned short usPortDirection;
    const unsigned short usLEDOut = 0x400;

    /* Set the LED bit to an output. */

    usPortDirection = inpw( mainLED_REG_DIR );
    usPortDirection &= ~usLEDOut;
    outpw( mainLED_REG_DIR, usPortDirection );
}
/*-----------------------------------------------------------*/

static void prvToggleLED( void )
{
    static short sLED = pdTRUE;
    unsigned short usLEDState;
    const unsigned short usLEDBit = 0x400;

    /* Flip the state of the LED. */
    usLEDState = inpw( mainLED_REG );

    if( sLED )
    {
        usLEDState &= ~usLEDBit;
    }
    else
    {
        usLEDState |= usLEDBit;
    }

    outpw( mainLED_REG, usLEDState );

    sLED = !sLED;
}