#include <luna/PathParser.h>
#include <os/ArgumentParser.h>
#include <os/File.h>
#include <os/FileSystem.h>

using os::File;

Result<int> luna_main(int argc, char** argv)
{
    StringView source;
    StringView destination;
    bool verbose { false };

    os::ArgumentParser parser;
    parser.add_description("Copy files or directories."_sv);
    parser.add_system_program_info("cp"_sv);
    parser.add_positional_argument(source, "source"_sv, true);
    parser.add_positional_argument(destination, "destination"_sv, true);
    parser.add_switch_argument(verbose, 'v', "verbose"_sv, "show more information"_sv);
    parser.parse(argc, argv);

    SharedPtr<File> source_file = TRY(os::File::open(source, File::ReadOnly));
    SharedPtr<File> destination_file;

    struct stat st;
    TRY(os::FileSystem::stat(source_file->fd(), st, true));
    umask(0);

    if (os::FileSystem::is_directory(destination, true))
    {
        auto basename = TRY(PathParser::basename(source));
        auto path = TRY(PathParser::join_paths(destination, basename.view()));

        destination_file = TRY(File::open_or_create(path.view(), File::ReadWrite, st.st_mode & ~S_IFMT));
    }
    else
        destination_file = TRY(File::open_or_create(destination, File::ReadWrite, st.st_mode & ~S_IFMT));

    if (verbose) os::eprintln("copying %s to %s", source.chars(), destination.chars());

    auto buf = TRY(Buffer::create_sized(4096));
    while (1)
    {
        TRY(source_file->read(buf, 4096));
        if (buf.is_empty()) break;
        destination_file->write(buf);
    }

    return 0;
}