#include "include/redirection.h"
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

void detectRedirections(char **args, Redirection *in, Redirection *out) {
    in->type = REDIRECT_NONE;
    in->filename = NULL;
    out->type = REDIRECT_NONE;
    out->filename = NULL;

    int j = 0;
    for (int i = 0; args[i] != NULL; i++) {
        if (strcmp(args[i], "<") == 0) {
            if (args[i + 1] != NULL) {
                in->type = REDIRECT_IN;
                in->filename = args[i+1];
                i++; // skip filename
            }
        } else if (strcmp(args[i], ">") == 0) {
            if (args[i + 1] != NULL) {
                out->type = REDIRECT_OUT;
                out->filename = args[i+1];
                i++;
            }
        } else if (strcmp(args[i], ">>") == 0) {
            if (args[i + 1] != NULL) {
                out->type = REDIRECT_APPEND;
                out->filename = args[i+1];
                i++;
            }
        } else {
            args[j++] = args[i];
        }
    }
    args[j] = NULL;
}

int applyRedirections(Redirection in, Redirection out) {
    if (in.type == REDIRECT_IN) {
        int fd = open(in.filename, O_RDONLY);
        if (fd < 0) {
            perror("open input");
            return -1;
        }
        if (dup2(fd, STDIN_FILENO) < 0) {
            perror("dup2 input");
            close(fd);
            return -1;
        }
        close(fd);
    }

    if (out.type == REDIRECT_OUT) {
        int fd = open(out.filename, O_WRONLY | O_CREAT | O_TRUNC, 0644);
        if (fd < 0) {
            perror("open output");
            return -1;
        }
        if (dup2(fd, STDOUT_FILENO) < 0) {
            perror("dup2 output");
            close(fd);
            return -1;
        }
        close(fd);
    } else if (out.type == REDIRECT_APPEND) {
        int fd = open(out.filename, O_WRONLY | O_CREAT | O_APPEND, 0644);
        if (fd < 0) {
            perror("open output append");
            return -1;
        }
        if (dup2(fd, STDOUT_FILENO) < 0) {
            perror("dup2 output append");
            close(fd);
            return -1;
        }
        close(fd);
    }
    return 0;
}