#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#define BUFFER_SIZE 1024
#define LRU_MAX 20
struct readData
{
    char op; //READ OR WRITE OPERAND
    int page; //PAGE REFERENCE
    int dirtyBit;
    int bit;
};
int pageNumber(int frameSize, int address)
{
    return floor(address/frameSize);
}
unsigned int hexToBin(char *HEX) //RETURNS DECIMAL OF A HEX STRING
{
    return (unsigned int)strtol(HEX, NULL, 16);
}
int main(int argc, char **argv)
{
    if(argc < 4)
    {
        printf("%s\n","YOU DONT HAVE ENOUGH ARGUMENTS");
        return -1;
    }
    /* OPENS A FILE, READS, AND TOKENIZES IT. STORES TOKENS IN AN ARRAY OF STRUCTURES  */
    char *filename = argv[1];
    FILE *inputFile = fopen(filename, "r");
    char buffer[BUFFER_SIZE];
    char *last_token;
    char delimit[] = " \n\f\v\t\r";
    int frameAmount = atoi(argv[3]);
    int frameSize = atoi(argv[2]);
    int frameCounter = 0;
    struct readData *data;
    data = malloc(sizeof(struct readData) * frameAmount);
    int index  = 0;

    //TEMP STORES
    char operand;
    int page, bit, dirtyBit;
    int events = 0;
    int writeCount = 0;
    int readCount = 0;
    //if W operation, set db to 1, so that when you replace it && db is 1 increment disk memory

    for(int i = 0; i < frameAmount; i++)
    {
        data[i].bit = 0;
        data[i].page = 0;
    }

    int readFlag = 0;
    while(fgets(buffer, BUFFER_SIZE, inputFile) != NULL)
    {
        last_token = strtok(buffer, delimit);
        while(last_token != NULL)
        {
            //WHILE TOKENIZING. CONVERT AND PUT THE ADDRESS INTO DATA STRUCT
            if(strcmp("W", last_token) == 0 || strcmp("R", last_token) == 0)
            {
                //THIS IS THE CASE WE HAVE AN OPERAND
                //STORE INTO THE OP OF THE STRUCT
                operand = *last_token;
                events++;
            }
            else
            {
                unsigned int address = hexToBin(last_token);
                page = pageNumber(frameSize, address);
            }
                readFlag++;
                readFlag = readFlag % 2;
                last_token = strtok(NULL, delimit);
        }
            //START REFERENCING HERE

    /* WHAT THE FUCK AM I DOING
     * ========================
     * the scenario that queue is full
     * A(1) - B(0) - C(1) - D(0) - E(1)
     * say we want to add F
     * TREAT IT LIKE A CLOCK INSTEAD WHERE EVERYONE STAYS STATIONARY
     * BUT INSTEAD YOU JUST MOVE THE HAND
     *          A(1)
     *      D(0)    B(0)
     *          C(1)
     *
     *  EXPLAINING WHAT THIS MEANS:
     *  start your handle at A
     *  then say you want to add F
     *  if A's reference bit is 1
     *  Set A's reference bit to 0
     *  and then move the handle
     *  then replace B with F set F's bit to 1.
     *  and then move the handle.
     *  Keep track of the handle at all times
     *  If you add something though and its already in the queue
     *  IVE GIVEN UP ON EFFICIENCY. JUST FUCKING SEARCH THE THING EVERY TIME
     */
        int found = 0;

        if(readFlag == 0)
        {
            for(int i = 0; i < frameSize; i++)
            {
                if (data[i].page == page)
                    found = 1;
                //DO NOTHING
            }
            if(found == 0)
            {
                if(data[index].bit == 0)
                {
                    data[index].bit = 1;
                    printf("%s%d%s%d\n", "WE ARE CURRENTLY CHANGING INDEXED PAGE: ", data[index].page, " TO: ", page);
                    data[index].page = page;

                    index++;
                    index = index % frameAmount;
                    //REPLACE
                } else if(data[index].bit == 1)
                {
                    //SET TO 0 AND INCREMENT COUNT
                    data[index].bit = 0;
                    index++;
                    index = index % frameAmount;
                }
            }
        }
        printf("%s%d\n", "CURRENT INDEX: ", index);

    }
        for(int i = 0; i < 8; i++)
        {
            printf("%s%d%s%d\n", "FRAME: ", i, " CONTAINS: ", data[i].page);
        }
        return 0;

}