#include "parser.h"

#include "../lib/malloc/malloc.h"
#include "../lib/cstr/cstr.h"

#include "../lib/sys/write.h"

char **__new_argv(char *exp);
void __free_argv(char **argv);

expression_list_t *new_expression_from_line(char *line)
{

	u64 n = cstr_split(line, '|');
	char *current = line;
	char *next    = 0;
	expression_list_t *head = 0;
	expression_list_t *expression = 0;

	for (; n > 0; --n) {
		next = (char*)next_split(current);

		strip_cstr(current, ' ');

		if (!expression) {
			expression = malloc(sizeof(expression_list_t));
			head = expression;
		} else {
			expression->next = malloc(sizeof(expression_list_t));
			expression = expression->next;
		}

		expression->call = current;
		expression->next = 0;

		current = next;
	}

	return head;
}


void free_expression(expression_list_t *expression)
{
	expression_list_t *next;

	while (expression) {
		next = expression->next;
		free(expression);
		expression = next;
	}
}


char **__new_argv(char *exp)
{
	u64 n = cstr_split(exp, ' ');
	char **argv = malloc(sizeof(char*) * n + 1);
	u64 i = 0;
	char *current = exp;
	char *next;

	for (; n > 0; --n) {
		next = (char*)next_split(current);
		strip_cstr(current, ' ');

		if (cstr_length(current))
			argv[i++] = current;

		current = next;
	}

	argv[i] = 0;

	return argv;
}


void __free_argv(char **argv)
{
	free(argv);
}

#ifdef PARSER_UNIT_TEST

#include "../lib/sys/execve.h"
#include "../lib/sys/fork.h"
#include "../lib/sys/wait4.h"
#include "../lib/sys/pipe.h"
#include "../lib/sys/dup2.h"
#include "../lib/sys/close.h"
#include "../lib/sys/io.h"
#include "../lib/sys/exit.h"

int main() {
	char in[] = "/bin/ls -a | /bin/wc -l";
	expression_list_t *exps = new_expression_from_line(in);
	expression_list_t *exp = exps;
	char **envp = { 0 };

	int pid[2];
	int pipefd[2];

	char **argv1 = __new_argv(exp->call);
	char **argv2 = __new_argv(exp->next->call);

	pipe(pipefd);
	pid[0] = fork();

	if (pid[0] == 0) {
		close(pipefd[0]);
		dup2(pipefd[1], STDOUT_FD);
		close(pipefd[1]);

		execve(argv1[0], argv1, envp);
	} else {
		pid[1] = fork();


		close(pipefd[1]);

		if (pid[1] == 0) {
			dup2(pipefd[0], STDIN_FD);
			close(pipefd[0]);

			execve(argv2[0], argv2, envp);
		} else {
			close(pipefd[0]);
			wait4(pid[0], 0, 0);
			wait4(pid[1], 0, 0);
		}
	}

	return 0;
}

#endif