/*
 * Copyright (C) 2014 Johannes Schauer <j.schauer@email.de>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2, as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 */

#define _POSIX_C_SOURCE 200809L // for strdup

#include <stdio.h>
#include <getopt.h>
#include <string.h>
#include <stdlib.h>

#include "options.h"

void print_help(const char *cmd)
{
    fprintf(stderr, "A shell to access a MediaFire account.\n");
    fprintf(stderr, "\n");
    fprintf(stderr, "Usage: %s [options]\n", cmd);
    fprintf(stderr, "\n");
    fprintf(stderr, "  -h, --help            Print this help\n");
    fprintf(stderr, "  -v, --version         Print version information\n");
    fprintf(stderr, "  -c, --command=<CMD>   Run command CMD and exit\n");
    fprintf(stderr, "  -u, --username=<USER> Login username\n");
    fprintf(stderr, "  -p, --password=<PASS> Login password\n");
    fprintf(stderr, "  -s, --server=<SERVER> Login server\n");
    fprintf(stderr, "  -i, --app-id=<id>     App ID\n");
    fprintf(stderr, "  -k, --api-key=<key>   API Key\n");
    fprintf(stderr, "\n");
    fprintf(stderr,
            "Username and password are optional. If not given, they\n"
            "have to be entered via standard input.\n");
    fprintf(stderr, "\n");
    fprintf(stderr, "You should not pass your password as a commandline\n"
            "argument as other users with access to the list of\n"
            "running processes will then be able to see it.\n");
    fprintf(stderr, "\n");
    fprintf(stderr,
            "Use the \"help\" command to print a list of available\n"
            "commands in the interactive environment:\n");
    fprintf(stderr, "\n");
    fprintf(stderr, "     %s -c help\n", cmd);
    fprintf(stderr, "\n");
    fprintf(stderr,
            "If arguments are given multiple times, the first one will be\n"
            "used.\n");
    fprintf(stderr, "\n");
    fprintf(stderr,
            "Arguments given on the commandline will overwrite arguments\n"
            "given in the configuration file\n");
    fprintf(stderr, "\n");
    fprintf(stderr,
            "The configuration file is parsed as if it was an argument\n"
            "string except that linebreaks are allowed between arguments.\n"
            "Lines starting with a # (hash) are ignored\n");
}

void parse_argv(int argc, char *const argv[],
                struct mfshell_user_options *opts)
{
    static struct option long_options[] = {
        {"command", required_argument, 0, 'c'},
        {"config", required_argument, 0, 'f'},
        {"username", required_argument, 0, 'u'},
        {"password", required_argument, 0, 'p'},
        {"server", required_argument, 0, 's'},
        {"app-id", required_argument, 0, 'i'},
        {"api-key", required_argument, 0, 'k'},
        {"help", no_argument, 0, 'h'},
        {"version", no_argument, 0, 'v'},
        {0, 0, 0, 0}
    };
    int             c;

    // resetting optind because we want to be able to call getopt_long
    // multiple times for the commandline arguments as well as for the
    // configuration file
    optind = 0;
    for (;;) {
        c = getopt_long(argc, argv, "c:u:p:s:hv", long_options, NULL);
        if (c == -1)
            break;

        switch (c) {
            case 'c':
                if (opts->command == NULL)
                    opts->command = strdup(optarg);
                break;
            case 'u':
                if (opts->username == NULL)
                    opts->username = strdup(optarg);
                break;
            case 'p':
                if (opts->password == NULL)
                    opts->password = strdup(optarg);
                break;
            case 's':
                if (opts->server == NULL)
                    opts->server = strdup(optarg);
                break;
            case 'f':
                if (opts->config == NULL)
                    opts->config = strdup(optarg);
            case 'i':
                if (opts->app_id == -1)
                    opts->app_id = atoi(optarg);
            case 'k':
                if (opts->api_key == NULL)
                    opts->api_key = strdup(optarg);
            case 'h':
                print_help(argv[0]);
                exit(0);
            case 'v':
                exit(0);
            case '?':
                exit(1);
                break;
            default:
                fprintf(stderr, "getopt_long returned character code %c\n", c);
        }
    }

    if (optind < argc) {
        // TODO: handle non-option argv elements
        fprintf(stderr, "Unexpected positional arguments\n");
        exit(1);
    }

    if (opts->password != NULL && opts->username == NULL) {
        fprintf(stderr, "You cannot pass the password without the username\n");
        exit(1);
    }
}