#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>

extern char **environ;
//
void hello()
{
    // ascci art: http://patorjk.com/software/taag/#p=testall&f=Cards&t=Fool%20OS
    puts(
                    
        "       ______            __   ____  _____      \n"
        "      / ____/___  ____  / /  / __ \\/ ___/     \n"
        "     / /_  / __ \\/ __ \\/ /  / / / /\\__ \\   \n"
        "    / __/ / /_/ / /_/ / /  / /_/ /___/ /       \n"
        "   /_/    \\____/\\____/_/   \\____//____/     \n"
        "                                               \n"
        "Welcome to FoolShell v0.2 (Compiled on " __DATE__ " at " __TIME__ "\n"
        "--------------------------------------------------------------------\n\n"
        "type 'help' anytime to show shell built-ins\n"
        "or execute user programms that are in the '/bin' directory (e.g. ls)\n"
    );
}

void prompt() 
{
    printf("%s",getenv("PS1"));
}

int main(int argc, char **argv) 
{

    bool silent=false;
    for(int i=0;i<argc;i++)
    {
	if(!strcmp(argv[i],"--silent"))silent=true;
    }
    
    if(!silent)hello();

    char *buf=malloc(256);

    while(1)
    {
	prompt();
        fgets(buf,255,stdin);
	buf[strlen(buf)-1]=0; // remove \n
	process(buf);
    }

    return 0;
}

char **tokenize(char *buf)
{

    char **token;
    token=malloc(10*sizeof(char*));

    int l=strlen(buf);

    int i;
    int c=0;

    for(i=0;i<l;i++)
    {  
	// init space for next token
	token[c]=malloc(256);

	//skip all the whitespace
	while(buf[i]==' '&&i<l)i++;
	if(i==l)break;

	//get token
	int t=0;

	while(buf[i]!=' '&&i<l)
	{
	    token[c][t]=buf[i];
	    t++;
	    i++;
	}
	token[c][t]=0;
	


//	printf("token %i : <%s>\n",c, token[c]);
	c++;
	token[c]=NULL;

    }

    return token;

}

int process(char *buf)
{
    
    char **token=tokenize(buf);
    char *command=token[0];
  //  puts(command);
    // copied from trottelshell

    if(!strcmp(command,"help"))
    {
	puts("foolshell: supported built-in commands: 'help', 'echo [string]', 'malloc [bytes]', 'free [address]', 'getenv [var]', 'putenv [var] [val]', 'env'");
    }
    else if(!strcmp(command,"echo"))
    {
	printf("\"%s\"\n",token[1]);

    }
    else if(!strcmp(command,"malloc"))
    {
	uint8_t *mall=malloc(atoi(token[1]));
	printf("allocated %d bytes at 0x%08X (%i).\n",atoi(token[1]),mall,mall);
    }
    else if(!strcmp(command,"free"))
    {
	free(atoi(token[1]));
	printf("called free(0x%08X).\n",atoi(token[1]));
    }
    else if(!strcmp(command,"getenv"))
    {
	printf("(0x%08X) put: %s = %s(0x%08X) \n",environ,token[1],getenv(token[1]),getenv(token[1]));
    }
    else if(!strcmp(command,"putenv"))
    {
	char buf[256];
	sprintf(buf,"%s=%s",token[1],token[2]);
	putenv(buf);
	printf("(0x%08X) set: %s = %s \n",environ,token[1],getenv(token[1]));
    }
    else if(!strcmp(command,"env"))
    {
	int i=0;
	printf("env: 0x%08X\n",environ);
	while(environ[i]!=NULL)
	{
	    printf("envvar %s (0x%08X)\n" ,environ[i],environ[i]);
	    i++;
	}
    }
    else
    {
	execve(token[0],token,0);
	char buf[256];
	sprintf(buf,"/bin/%s",token[0]);
	execve(buf,token,environ);
	puts("foolshell: command not found");
    }

}