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

long GetFileSize(FILE* f){
    fseek(f, 0, SEEK_END);
    long size = ftell(f);
    fseek(f, 0, SEEK_SET);
    return size;
}

void DumpMemory(char *memory, char *filename){
    FILE *dump = fopen(filename, "wb");
    fwrite(memory, 1, strlen(memory), dump);
    fclose(dump);
}

int main(int argc, char **argv){
    
    long mem_size = 0;
    char filename[255];
    
    FILE *rom = fopen("ROM.bin","rb");
    mem_size = mem_size + GetFileSize(rom);
    
    //Handling arguments
    if(argc < 2){
	printf("too few arguments\n");
	return 1;
    }
    for(int i = 1; i < argc; i++){
	if(strcmp(argv[i], "-m") == 0 || strcmp(argv[i], "--memory") == 0){
	    char *endptr;
	    long convert = strtol(argv[i+1], &endptr, 10);
	    mem_size = &endptr != NULL ? mem_size + convert : mem_size;
	}
	if(strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0){
	    printf("Usage: %s [OPTIONS] --file filename\nOptions:\n%s-m, --memory: specify RAM size\n%s-h, --help: print this message\n\n",argv[0],"    ","    ");
	    return 0;
	}
	if(strcmp(argv[i], "-f") == 0 || strcmp(argv[i], "--file") == 0){
	    for(int j = 0; j < strlen(argv[i+1]); j++){
		filename[j] = argv[i+1][j];
	    }
	}
    }

    FILE *program = fopen(filename, "rb");
    if(program == NULL){
	printf("ERROR: file does not exist");
	return 2;
    }
    long program_size = GetFileSize(program);
    mem_size = mem_size + program_size;

    //Intializing memory and stuff

    long PC = 0; //program counter
    char *memory = (char *)malloc(mem_size * sizeof(char)); //Allocating RAM
    if(memory == NULL){
	printf("ERROR: Memory allocation failed (Buy more RAM)");
	return 3;
    }
    //Copying program to memory
    {
	char buffer[program_size];
	fread(buffer, 1, program_size, program);
	for(int i = 0; i <= program_size; i++){
	    memory[mem_size-i] = buffer[program_size-i];
	}
    }
    fclose(program);
    //Copying ROM to memory
    {
	long size = GetFileSize(rom);
	char buffer[size];
	fread(buffer, 1, size, rom);
	for(int i = 0; i < size; i++){
	    memory[mem_size-program_size-1-i] = buffer[size-i];
	}
    }
    fclose(rom);

    DumpMemory(memory, "out.bin");
    
    free(memory);
    return 0;
}