#include "sh.h"
#include <errno.h>
#include <os/ArgumentParser.h>
#include <stdlib.h>

shell_builtin_t builtin_set = [](int argc, char** argv) -> Result<void> {
    StringView name;
    StringView value;
    bool preserve { false };

    os::ArgumentParser parser;
    parser.set_should_exit_on_bad_usage(false);
    parser.add_description("Set an environment variable (shell builtin)"_sv);
    parser.add_system_program_info("set"_sv);
    parser.add_positional_argument(name, "name"_sv, true);
    parser.add_positional_argument(value, "value"_sv, true);
    parser.add_switch_argument(preserve, 'p', "preserve"_sv,
                               "preserve the environment variable if it already exists"_sv);
    if (!TRY(parser.parse(argc, argv))) return {};

    if (setenv(name.chars(), value.chars(), !preserve) < 0) return err(errno);

    return {};
};