argument.h

/*
 * Copyright 2025 Dominik Czekai
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#pragma once
#include <any>
#include <string>
#include <string_view>
#include <typeindex>
 
namespace cli::commands
{
 
enum class ArgumentKind
{
    Positional,
    Option,
    Flag,
};
 
namespace docwriting
{
class DocWriter; // Forward declaration
}
 
class ArgumentBase
{
public:
    virtual ~ArgumentBase() = default;
 
#pragma region Accessors
 
    [[nodiscard]] constexpr std::string_view getName() const noexcept { return name; }
 
    [[nodiscard]] constexpr std::string_view getOptionComment() const noexcept
    {
        return optionsComment;
    }
 
    [[nodiscard]] constexpr bool isRequired() const noexcept { return required; }
 
    [[nodiscard]] constexpr bool isRepeatable() const noexcept { return repeatable; }
 
    [[nodiscard]] constexpr ArgumentKind getArgType() const { return argType; }
 
    [[nodiscard]] virtual std::string getOptionsDocString(
        const docwriting::DocWriter &writer) const = 0;
 
    [[nodiscard]] virtual std::string getArgDocString(
        const docwriting::DocWriter &writer) const = 0;
#pragma endregion Accessors
 
protected:
    ArgumentBase(std::string_view name, std::string_view optionsComment, ArgumentKind argType,
                 bool repeatable, bool required)
        : name(name), optionsComment(optionsComment), argType(argType), repeatable(repeatable),
          required(required)
    {
    }
 
    const std::string name;
    std::string optionsComment;
    const ArgumentKind argType;
    bool repeatable{false};
    bool required{true};
};
 
class TypedArgumentBase
{
public:
    virtual ~TypedArgumentBase() = default;
 
    [[nodiscard]] std::type_index getType() const { return type; }
 
    [[nodiscard]] virtual std::any parseToValue(const std::string &input) const = 0;
 
protected:
    explicit TypedArgumentBase(std::type_index t) : type(t) {}
 
    const std::type_index type;
};
 
class FlaggedArgumentBase
{
public:
    [[nodiscard]] constexpr std::string_view getShortName() const noexcept { return shortName; }
 
protected:
    explicit FlaggedArgumentBase(std::string_view shortName) : shortName(shortName) {}
 
    std::string shortName;
};
 
} // namespace cli::commands