#include "configops.h"
#include "metadataops.h"
#include "StandardConstants.h"
#include "simulator.h"

/*
Name: createProcessList
Process: reads through the opcode struct to fill out the linked list of PCBs
Function Input/Parameters: metadata (OpCodeType *)
Function Output/Parameters: none
Function Output/Returned: head pointer to the PCBs
Device Input/Device: none
Device Output/Device: none
Dependencies: malloc, sizeof, ???
*/
ProcessControlBlockLL *createProcessList(OpCodeType *metadataPtr)
{
    // allocate and create the ProcessControlBlockLL using malloc and size of
    ProcessControlBlockLL *headBlock;
    headBlock = malloc(sizeof(ProcessControlBlockLL));
    // set the head pointer to NULL
    headBlock->headPtr = NULL;
    // return headBlock
    return headBlock;
}

/*
Name: destroyProcessList
Process: deallocates memory used for the linked list struct
Function Input/Parameters: head pointer to linked list (ProcessControlBlockLL *)
Function Output/Parameters: none
Function Output/Returned: NULL
Device Input/Device: none
Device Output/Device: none
Dependencies: free, destroyProcessListHelper, ???
*/
ProcessControlBlockLL *destroyProcessList(ProcessControlBlockLL *linkedListPtr)
{
    // call the first destroyProcessListHelper
    destroyProcessListHelper(linkedListPtr->headPtr);
    // free the rest of the struct
    free(linkedListPtr);
    // return null
    return NULL;
}

/*
Name: destroyProcessListHelper
Process: recursively clears the PCB linked list struct, freeing the struct
Function Input/Parameters: head pointer to linked list (ProcessControlBlockLL *)
Function Output/Parameters: none
Function Output/Returned: NULL
Device Input/Device: none
Device Output/Device: none
Dependencies: free, destroyProcessListHelper(recursively), ???
*/
ProcessControlBlock *destroyProcessListHelper(ProcessControlBlock *nodePtr)
{
    // check to see if the next pointer is NOT null
    if(nodePtr->nextPtr != NULL)
    {
        // if not null, move to the next pointer (recurse)
        nodePtr->nextPtr = destroyProcessListHelper(nodePtr->nextPtr);
    }
    // free the 'parent' node
    free(nodePtr);
    // return null
    return NULL;
}

/*
Name: runSim
Process: primary simulation driver
Function Input/Parameters: configuration data (ConfigDataType *),
                           metadata (OpCodeType *)
Function Output/Parameters: none
Function Output/Returned: none
Device Input/Device: none
Device Output/Device: none
Dependencies: ???
*/
void runSim(ConfigDataType *configPtr, OpCodeType *metaDataMstrPtr)
{
    // initialize function/variables
        // need a FILE * for file operations
        // need two working pointers, one for master loop, one for internal loop
        // currentTime variable that stores the time.
    // create the process list with createProcessList
    // function holds master loop, loops until sys end opcode found OR PCB List != NULL
        // will have a loop that goes from app start to app end for a PCB 
        // (checks to see if the next instruction is NOT app end), using getNextProcess?
            // this will getNextOpCode
            // this will checkForIO and run the IO operations, outputting to FILE * and/or monitor
                // checkForIO will need the FILE * passed, will need timer access, and ???
            // this will checkForCPU and run the CPU operations, outputting to FILE * and/or monitor
                // checkForCPU will need the FILE * passed, will need timer access, and ???
        //
    // deallocate the process list with destroyProcessList
    printf("runSim called here");
    // void function, no return.
}

    // getNextProcess/scheduler/dispatcher run here, loads/"runs" the process
    // getNextOpCode, not needed for Sim02 apparently, keep in mind.
    // checkForIO, I think this gets passed the current process and runs the IO ops
    // checkForCPU, I think this gets passed the current process and runs the CPU ops
    // checkForMemory, I think this gets passed the current process 
        // and runs mem ops (not needed for Sim02)
    // cpuIdler (not needed for Sim02)