#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "proto.h"

/* Constants */ 

#define LINELEN 1024
#define EXPANDEDLEN 200000

/* Globals */
 int last_exit_status = 0;
 int m_argc;
 int m_shifted_argc;
 char **m_argv;
 char **m_shifted_argv;

/* Prototypes */

void processline (char *line, int outFD, int waitFlag);
void print_args(char **args);

/* Shell main */

int main (int mainargc, char **mainargv)
{
	// Defining Locals
	char *promptStr;
    char   buffer [LINELEN];
    int    len;
    FILE *fp;

    m_argc = mainargc;
    m_shifted_argc = mainargc;
	m_argv = mainargv;
	m_shifted_argv = mainargv;

    if(m_argc > 1) fp = fopen(m_argv[1], "r");
    else fp = stdin;

    if(fp == NULL)
    {
   		fprintf(stderr, "./msh: Can not open file %s\n", m_argv[1]);
    	exit(127);
    }

    while(1)
    {
    	if(fp == stdin)
		{
			if(!(promptStr = getenv("P1"))) fprintf(stderr, "%% ");
			else fprintf(stderr, promptStr);
		}
		
    	if(fgets(buffer, LINELEN, fp) != buffer) break;

    	len = strlen(buffer);
		if (buffer[len-1] == '\n') buffer[len-1] = 0;

		processline (buffer, 1, 1); //, mainargc, mainargv, shiftedMArgV);
    }

    if (!feof(fp)) perror ("read");
    if(fclose(fp) != 0) perror("close");
    return 0;		/* Also known as exit (0); */
}


void processline (char *line, int outFD, int waitFlag) //, int mainargc, char **mainargv, char **shiftedMArgV)
{
    pid_t  cpid;
    int    status;
	/* All the parsed arguments, will be passed to exec */
	/* int expanded_len = 2048;*/
	char expanded_line[EXPANDEDLEN];
	char **args;
	int command_count;
	/* int index = 0; */
	
	if(expand(line, expanded_line, EXPANDEDLEN)) return; //, mainargc, mainargv, shiftedMArgV)) return;

	fprintf(stderr, "strlen(expanded) = %d\n", (int)strlen(expanded_line));
	
	command_count = arg_parse(expanded_line, &args);

	if(!command_count) return;

	if(!exec_if_built_in(args, outFD))
	{	
		/* Start a new process to do the job. */
		cpid = fork();
		if (cpid < 0) {
			perror ("fork");
			free(args);
			return;
		}
		
		/* Check for who we are! */
		if (cpid == 0) {
		  /* We are the child! */
	
			/* Turning stdout into pipe output if needed */
			if((dup2(outFD, 1)) < 0)
			{
				perror("dup");
				return;
			}
			
			execvp(args[0], args);
			perror ("exec");
			exit (127);
			last_exit_status = 127;
		}
		
		/* Have the parent wait for child to complete */
		if(waitFlag)
		{
			if (wait (&status) < 0) perror ("wait");
			last_exit_status = ((WEXITSTATUS(status) || !WIFEXITED(status)) ? 127 : 0);
		}
	}
	free(args);
}


/* Procedure for testing purposes,
prints the arguments of a command array */
void print_args(char **args)
{
	int i = 0;
	char** cmd = args;
	
	printf("COMMANDS: ");
	while(cmd[i] != 0) 
	{
		printf("'%s'\n", cmd[i]);
		i++;
	}
}