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

#include <reent.h>

extern char **environ;
extern struct _reent *_impure_ptr;

uint8_t buf_test[1024*300];

//
void hello()
{
    // ascci art: http://patorjk.com/software/taag/#p=testall&f=Cards&t=Fool%20OS
    puts(

    "\033c"
    "\033[36m"
                    
    "       ______            __   ____  _____      \n"
    "      / ____/___  ____  / /  / __ \\/ ___/     \n"
    "     / /_  / __ \\/ __ \\/ /  / / / /\\__ \\   \n"
    "    / __/ / /_/ / /_/ / /  / /_/ /___/ /       \n"
    "   /_/    \\____/\\____/_/   \\____//____/     \n"
    "                                               \n"

    "\033[37;44m"
    "                                               \n"

    "  Welcome to FoolShell v0.12 (Compiled on " __DATE__ " at " __TIME__")\n"
    "  ------------------------------------------------------------------\n\n"
    "  Please type 'help' anytime, to show shell \"built-ins\". You can execute \n"
    "  user programms that are in your $PATH directory by simply typing \n"
    "  their filenames. Get additional information for many, of the available\n"
    "  commands by invoking them with --help or -h. (e.g. ls --help) \n"
    "                                               \n"

    "\033[37;40m"
    );

    printf("  Your $PATH is currently set to: %s\n",getenv("PATH"));
    printf("  Type 'ls %s' to list programms on your $PATH.\n\n",getenv("PATH"));
}

void prompt() 
{
    printf("\033[36mfool\033[37m@\033[32mhill\033[33m:%s%s\033[37m",getenv("PWD"),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=calloc(sizeof(char),256);

    setvbuf(stdin,NULL,_IONBF,0);
    setvbuf(stdout,NULL,_IONBF,0);

    while(1)
    {
	prompt();
	int bl=0;

	while(1)
	{
	    char c=fgetc(stdin);

	    if(c=='\b')
	    {
		if(bl==0)continue;
		buf[--bl]='\0';
		putc(c,stdout);
	    }
	    else
	    {
		putc(c,stdout);
		if(c=='\n')break;
		buf[bl]=c;
		buf[++bl]='\0';
	    }
	}

        //fgets(buf,255,stdin);
	//buf[strlen(buf)-1]=0; // remove \n
	//printf("[%s]",buf);
	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(   "\nfoolshell: supported built-in commands:\n\n" 
                "'help'                      - show this message\n"
                "'echo [string]'             - print given string to stdout\n"
                "'getenv [var]'              - show environment variable\n"
                "'putenv/setenv [var] [val]' - set environemnet variable\n"
                "'env'                       - show all environment variables\n"
                "'cd [dir]'                  - change directory (set $PWD)\n"
                "'exit'                      - exit running foolshell\n\n");
    }

    else if(!strcmp(command,"cd"))
    {
	char *dir=getenv("PWD");

	char buf[256];

	if(token[1][0]!='/')
	{
	    sprintf(buf,"%s%s%s",dir,dir[0]=='/'&&dir[1]==0?"":"/",token[1]);
	}
	else
	{
	    sprintf(buf,"%s",token[1]);
	}

	char token[10];

	//adjust pwd (resolve '..' and '.')
////	printf("adjusting pwd: '%s'\n",buf);
	int left=1;
	int right=0;

	do{

	    int t=0;
	    do
	    {
		right++;
		token[t]=buf[right];

		t++;
	    }
	    while(buf[right]!=0&&buf[right]!='/');
	    token[t-1]=0;
	    
//	    printf("path token: '%s'\n",token);
	    
	    if(!strcmp(token,".."))
	    {
		left--;
		while(buf[left]!='/')left--;
	    }
	    else if(!strcmp(token,"."))
	    {
	    }
	    else
	    {
		int i=0;
		if(left!=1)buf[left++]='/';
		do{buf[left++]=token[i++];}while(token[i]!=0);
	    }

	}while(buf[right]!=0);
	buf[left]=0;
//	printf("adjusted: '%s'\n",buf);
	if(buf[0]==0)setenv("PWD","/",1);
	else setenv("PWD",buf,1);
    }
    else if(!strcmp(command,"exit"))
    {
	_exit(1);
    }
    else if(!strcmp(command,"echo"))
    {
	printf("\"%s\"\n",token[1]);

    }
    else if(!strcmp(command,"getenv"))
    {
	printf("(0x%08X) get: '%s' = '%s'(0x%08X) \n",environ,token[1],getenv(token[1]),getenv(token[1]));
    }
    else if(!strcmp(command,"putenv")||!strcmp(command,"setenv"))
    {
	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
    {
	int pid=_fork();

	if(pid==0)
	{
	    sprintf(buf,"%s",token[0]);
	    _execve(buf,token,environ);
	    sprintf(buf,"%s/%s",getenv("PATH"),token[0]);
	    _execve(buf,token,environ);
	    puts("foolshell: command not found");
	    exit(0);
	}
	
	if(token[1]!=NULL&&strcmp(token[1],"branch"))_wait(pid);

    }
    return 0;
}