#include <stdio.h>
#include <conio.h>
#include <string.h>
#include <stdlib.h>

static int buffer[65536];
int MaxAddress = 0;

int LineAnalysis(char *line, int *ByteCount, int *Address, int *RType, int Data[], int *TempAdd){
    char ArrTemp[20];
    int sum, CheckSum, Pos = 9;

    if(line[0] != ':' || strlen(line) < 11) return 1;

    strncpy(ArrTemp, line+1, 2);
    ArrTemp[2] = '\0';
    *ByteCount = strtol(ArrTemp, NULL, 16);
    ArrTemp[0] = '\0';
    if(*ByteCount != ((strlen(line)-11)/2)) return 1;

    strncpy(ArrTemp, line+3, 4);
    ArrTemp[4] = '\0';
    *Address = strtol(ArrTemp, NULL, 16);
    ArrTemp[0] = '\0';

    strncpy(ArrTemp, line+7, 2);
    ArrTemp[2] = '\0';
    *RType = strtol(ArrTemp, NULL, 16);
    ArrTemp[0] = '\0';
    if(*RType > 5) return 1;

    sum = (*ByteCount & 255) + ((*Address >> 8) & 255) + (*Address & 255) + (*RType & 255);

    if(*RType == 4){
        strncpy(ArrTemp, line+Pos, 4);
        ArrTemp[4] = '\0';
        *TempAdd = strtol(ArrTemp, NULL, 16);
        ArrTemp[0] = '\0';
    }

    for(int i=0; i < *ByteCount; i++){
        strncpy(ArrTemp, line+Pos, 2);
        ArrTemp[2] = '\0';
        Data[i] = strtol(ArrTemp, NULL, 16);
        sum += (Data[i] & 255);
        ArrTemp[0] = '\0';
        Pos += 2;
    }

    strncpy(ArrTemp, line+Pos, 2);
    ArrTemp[2] = '\0';
    CheckSum = strtol(ArrTemp, NULL, 16);
    ArrTemp[0] = '\0';

    if(((sum & 255) + (CheckSum & 255)) & 255){
        printf("This line has ERROR CHECKSUM \n");
        return 1;
    }
    return 0;
}

int OpenFile(char *FileHex){
    int NumLine = 1;
    int ByteCount, Address, RType, Data[256], TempAdd, flag;
    char line[300];
    FILE *fp;
    fp = fopen(FileHex, "r"); //mo file Hex

    //Neu khong mo duoc file Hex se dua ra thong bao
    if(fp == NULL){
        printf("Error: %s could not be opened.", FileHex);
        return 1;
    }

    while(!feof(fp)){
        line[0] = '\0';
        fgets(line, 300, fp);
        if(ferror(fp)){
            printf("Error when read Line %d", NumLine);
            return 1;
        }
        if(line[strlen(line)-1]=='\n' || line[strlen(line)-1]=='\r')  line[strlen(line)-1] = '\0';
        if(LineAnalysis(line, &ByteCount, &Address, &RType, Data, &TempAdd) == 1){
            printf("ERROR: Line %d", NumLine);
            return 1;
        }
        else{
            if(RType == 1){
                fclose(fp);
                return 0;
            }
            if(RType == 4 && TempAdd > 0) flag = 0;
            if(RType == 4 && TempAdd == 0) flag = 1;
            if(RType == 0 && flag == 1){
                for(int i = 0; i < ByteCount; i++){
                    buffer[Address] = Data[i];
                    if(Address > MaxAddress) MaxAddress = Address;
                    Address++;
                }
            }
        }
        NumLine++;
    }
    return 0;
}

int main(int argc, char *argv[]){
    int LineCount = 1, choose, TempData;
    if(argc != 2){
        printf("Need Hex file name.\n");
        printf("To run, type 'HexDisplay Hex_File_Name.hex'\n");
        return 0;
    }
    for(int i = 0; i < 65536; i++){
        buffer[i] = 255;
    }
    if(OpenFile(argv[1]) == 1) return 0;

    for(int i = 0; i <= MaxAddress; i++){
        if(LineCount % 25 == 1 && LineCount != 1){
            printf("Do you want to continue printing?\n");
            printf("1: Yes      2: No\n");
            scanf("%d", &choose);
            if(choose == 1){
                system("cls");
                LineCount = 1;
            }
            else if(choose == 2){
                printf("Thanks for using. Bye bye <3");
                return 0;
            }
        }
        if(i % 16 == 0){
            printf("%04X  :  %02X ", i, buffer[i]);
        }
        else if(i % 16 == 15){
            printf("%02X  :  ", buffer[i]);
            for(int j = i - 15; j <= i; j++){
                if(buffer[j] < 32) TempData = 46;
                else TempData = buffer[j];
                printf("%c ", TempData);
            }
            printf("\n");
            LineCount++;
        }
        else printf("%02X ", buffer[i]);
        if(i == MaxAddress && (i % 16) != 15){
            for(int j = i+1; j <= (i + (15 - (i%16))); j++){
                printf("%2X ", buffer[j]);
            }
            printf(": ");
            for(int j = i - (i%16); j <= (i + (15 - (i%16))); j++){
                if(buffer[j] < 32) TempData = 46;
                else TempData = buffer[j];
                printf("%c ", TempData);
            }
            printf("\n");
        }
    }
    printf("End program. Thanks for using. Bye bye <3");
    return 0;
}