#include "api.h"
#include "lib.h"
#define ALWAYS_REPORT_EXIT_CODE 0
#define PROMPT "->"
#define BUF_LEN 256
char curr_line[BUF_LEN];
int count;
int read_line() {
	for(int i=0;i<BUF_LEN;++i) {
		char c = getch();
		switch(c) {
			case 0: // null byte, probably a keyboard key we've not mapped yet.
				--i;
				continue;
			case 8: // backspace.
				i-=2;
				continue;
			case '\n':
				c=0;
			default:
				curr_line[i]=c;
				break;
		}
		if(c==0)
			return i;
	}
	return -1;
}
int main(void) {
	print("Welcome to the shell ;)\n");
	for(;;) {
		print(PROMPT);
		flush();
		int len=read_line();
		if(len==-1) {
			printf("\nLine too long!\n");
			continue;
		}
		if(len==0)
			continue;
		int background=0;
		if(curr_line[len-1]=='&') {
			background=1;
			curr_line[len-1]=0;
		}
		int program_fd =sys_open(curr_line,0);
		if(program_fd==-1) {
			printf("No such program: %s - errno=%d\n",curr_line,errno);
			continue;
		}
		int retval=0;
		int childpid=sys_fork();
		switch(childpid) {
			case -1: printf("Error forking: %d\n",childpid);
					break;
			case 0:
				sys_exec(program_fd);
				print("Could not execute program\n");
				sys_exit(1);
				// doesn't return...
			default:
				sys_close(program_fd);
				if(background==1) {
					printf("Running %d in background.\n",childpid);
				}else{
					sys_wait(&retval);
					if(retval || ALWAYS_REPORT_EXIT_CODE)
					printf("%s returned %d\n",curr_line,retval);
				}
				break;
		}
	}
	return 0;
}