#ifndef YERBACON_ARGUMENTS_HPP
#define YERBACON_ARGUMENTS_HPP

#include <iostream>
#include <utility>
#include <string>
#include <string_view>
#include <span>

using namespace std;

class Argument {
protected:
    const string longVersion;
    virtual bool is(string_view str) {
        bool hasPrefix = str.starts_with("--");
        if (hasPrefix) str.remove_prefix(2);
        return (not str.empty()) && longVersion == str && hasPrefix;
    }
public:
    bool operator ==(const string_view it) { return is(it); }
    explicit Argument(string name): longVersion(move(name)) {}
};

class ArgumentAssignable: public Argument {
    vector<string_view> values;
public:
    static string getValueFor(const string& str) {
        unsigned long definePos = str.find_last_of('=') + 1;
        return str.size() > definePos ? str.substr(definePos) : string();
    }
    ArgumentAssignable(string name, const span<string_view>& possibleValues) : Argument(move(name)), values() {
        values.reserve(possibleValues.size());
        move(possibleValues.begin(), possibleValues.end(), back_inserter(values));
    }
    explicit ArgumentAssignable(const string& name): ArgumentAssignable(name, span<string_view>()) {}; // To use when we don't want the argument's possible values to be checked
protected:
    bool is(string_view str) override {
        if (str.find_last_of('=') != string_view::npos && !str.empty()) {
            auto isValid = [&]() -> bool { return str.starts_with("--" + longVersion + '='); };
            if (values.empty()) return isValid();
            for (const auto& value : values) {
                if (str.ends_with(value.substr(1, value.size()))) {
                    return isValid();
                }
            }
        }
        return false;
    }
};

struct ArgumentShort: public Argument {
    const string shortVersion;
    ArgumentShort(string shortName, string name): Argument(move(name)), shortVersion(move(shortName)) {}
    explicit ArgumentShort(string name): ArgumentShort(string(1, name.at(0)), name) {}
protected:
    bool is(string_view string) override {
        return Argument::is(string) || (!string.empty() && shortVersion == string.substr(1, string.size()));
    }
};

#endif //YERBACON_ARGUMENTS_HPP