fview.cpp

/*
 * Copyright (C) 2025  Tete
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include <filesystem>
#include <iostream>
#include <vector>
#include <fstream>
#include <unistd.h>
#include "argh.h"

typedef bool FLAG;

template<typename... vT>
__inline void cout_print(const vT&... vals)
{
    (std::cout << ... << vals);
}

std::vector<std::string> get_lines_file(const std::string& path)
{
    std::vector<std::string> lines;

    std::ifstream file = std::ifstream(path);
    std::string line;


    while (std::getline(file, line))
    {
        lines.push_back(line);
    }

    return lines;
}

std::vector<std::string> get_lines_cin()
{
    std::vector<std::string> lines;

    std::string line;
    while (std::getline(std::cin, line))
    {
        lines.push_back(line);
    }
    return lines;
}

#define REP_BUG_TEXT "Copyright (C) 2025  Tete.\nFor Docs and bug reporting\nplease see: <https://github.com/tetex7/fview>."
void help(int ecode = 0)
{
    cout_print("Usage: fview [options] [PATH_TO_FILE]\n");
    cout_print("FVIEW HELP:\n",
        "--no-head, -n       : dons't print \"START/END VIEW\" msg\n",
        "--help,    -h       : you'r reading it lol\n"
    );

    cout_print("\n\n");
    cout_print(FV_VER, '\n');
    cout_print(REP_BUG_TEXT, '\n');
    exit(ecode);
}

int main(const int argc, const char** argv)
{
    FLAG SE_WAR = 1;
    const auto cmdl = argh::parser(argc, argv);

    if (cmdl[{"-h", "--help"}])
        help(0);

    if (cmdl[{"-n", "--no-head"}])
        SE_WAR = 0;

    FLAG use_cin = 0;
    std::string file_path;

    if (!isatty(STDIN_FILENO))
    {
        use_cin = 1;
    }
    else if (!argc)
    {
        help(1);
    }

    if ((argc > 1) && (cmdl.pos_args()[cmdl.size()-1] != argv[0]))
    {
        file_path = cmdl.pos_args()[cmdl.size()-1];
    }
    else if (!use_cin)
    {
        help(1);
    }

    if(!std::filesystem::exists(file_path) && !use_cin)
    {
        cout_print(file_path, " dosn't exists\n");
        help(1);
    }

    std::vector<std::string> lines; //= get_lines(file_path, use_cin);

    if (use_cin)
    {
        lines = get_lines_cin();
    }
    else
    {
        lines = get_lines_file(file_path);
    }

    if (SE_WAR) cout_print("START OF VIEW:\n");

    for (size_t i = 0; i < lines.size(); i++)
    {
        if (i < 9)
        {
            cout_print(i+1, "   | ", lines[i], '\n');
        }
        else if (i < 99)
        {
            cout_print(i+1, "  | ", lines[i], '\n');
        }
        else if (i < 999)
        {
            cout_print(i+1, " | ", lines[i], '\n');
        }
        else
        {
            cout_print("BFN", " | ", lines[i], '\n');
        }
    }
    if(SE_WAR) cout_print("END OF VIEW\n");

    return 0;
}