// GitHub source: from https://github.com/tanakh/cmdline
// Modifications made in-place to remove the use of exceptions,
// flagged with HALIDE_WITH_EXCEPTIONS

/*
  Copyright (c) 2009, Hideyuki Tanaka
  All rights reserved.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:
  * Redistributions of source code must retain the above copyright
  notice, this list of conditions and the following disclaimer.
  * Redistributions in binary form must reproduce the above copyright
  notice, this list of conditions and the following disclaimer in the
  documentation and/or other materials provided with the distribution.
  * Neither the name of the <organization> nor the
  names of its contributors may be used to endorse or promote products
  derived from this software without specific prior written permission.

  THIS SOFTWARE IS PROVIDED BY <copyright holder> ''AS IS'' AND ANY
  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  DISCLAIMED. IN NO EVENT SHALL <copyright holder> BE LIABLE FOR ANY
  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#pragma once

#include <algorithm>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <map>
#include <sstream>
#include <stdexcept>
#include <string>
#include <typeinfo>
#include <vector>

#if defined(_MSC_VER) && !defined(NOMINMAX)
#define NOMINMAX
#endif

#if !defined(_WIN32)
#include <cxxabi.h>
#else
#include <windows.h>
#pragma warning(disable : 4091)
#include <dbghelp.h>
#pragma comment(lib, "dbghelp.lib")
#endif

namespace cmdline {

namespace detail {

#ifdef HALIDE_WITH_EXCEPTIONS
inline void throw_bad_cast() {
    throw std::bad_cast();
}
#else
inline void throw_bad_cast() {
    std::cerr << "bad cast\n";
    exit(1);
}
#endif

template<typename Target, typename Source, bool Same>
class lexical_cast_t {
public:
    static Target cast(const Source &arg) {
        Target ret;
        std::stringstream ss;
        if (!(ss << arg && ss >> ret && ss.eof())) {
            throw_bad_cast();
        }

        return ret;
    }
};

template<typename Target, typename Source>
class lexical_cast_t<Target, Source, true> {
public:
    static Target cast(const Source &arg) {
        return arg;
    }
};

template<typename Source>
class lexical_cast_t<std::string, Source, false> {
public:
    static std::string cast(const Source &arg) {
        std::ostringstream ss;
        ss << arg;
        return ss.str();
    }
};

template<typename Target>
class lexical_cast_t<Target, std::string, false> {
public:
    static Target cast(const std::string &arg) {
        Target ret;
        std::istringstream ss(arg);
        if (!(ss >> ret && ss.eof())) {
            throw_bad_cast();
        }
        return ret;
    }
};

template<typename T1, typename T2>
struct is_same {
    static const bool value = false;
};

template<typename T>
struct is_same<T, T> {
    static const bool value = true;
};

template<typename Target, typename Source>
Target lexical_cast(const Source &arg) {
    return lexical_cast_t<Target, Source, detail::is_same<Target, Source>::value>::cast(arg);
}

static inline std::string demangle(const std::string &name) {
#if !defined(_WIN32)
    int status = 0;
    char *p = abi::__cxa_demangle(name.c_str(), nullptr, nullptr, &status);
    std::string ret(p);
    free(p);
    return ret;
#else
    char demangled_name[8192];
    if (UnDecorateSymbolName(name.c_str(), demangled_name, sizeof(demangled_name),
                             UNDNAME_COMPLETE)) {
        std::string ret(demangled_name);
        return ret;
    } else {
        DWORD error = GetLastError();
        std::cout << "UnDecorateSymbolName error: " << error << std::endl;
        return name;
    }
#endif
}

template<class T>
std::string readable_typename() {
#ifndef HALIDE_ENABLE_RTTI
    return "unrecognized type";
#else
    return demangle(typeid(T).name());
#endif
}

template<class T>
std::string default_value(T def) {
    return detail::lexical_cast<std::string>(def);
}

template<>
inline std::string readable_typename<std::string>() {
    return "string";
}

#ifndef HALIDE_ENABLE_RTTI
template<>
inline std::string readable_typename<bool>() {
    return "bool";
}

template<>
inline std::string readable_typename<int>() {
    return "int";
}
#endif

}  // namespace detail

//-----

#ifdef HALIDE_WITH_EXCEPTIONS
class cmdline_error : public std::exception {
public:
    cmdline_error(const std::string &msg)
        : msg(msg) {
    }
    ~cmdline_error() throw() override = default;
    const char *what() const throw() override {
        return msg.c_str();
    }

private:
    std::string msg;
};
inline void throw_cmdline_error(const std::string &s) {
    throw cmdline::cmdline_error(s);
}
#else
inline void throw_cmdline_error(const std::string &s) {
    std::cerr << "error: " << s << "\n";
    exit(1);
}
#endif

template<class T>
struct default_reader {
    T operator()(const std::string &str) {
        return detail::lexical_cast<T>(str);
    }
};

template<class T>
struct range_reader {
    range_reader(const T &low, const T &high)
        : low(low), high(high) {
    }
    T operator()(const std::string &s) const {
        T ret = default_reader<T>()(s);
        if (!(ret >= low && ret <= high)) {
            throw_cmdline_error("range_error");
        }
        return ret;
    }

private:
    T low, high;
};

template<class T>
range_reader<T> range(const T &low, const T &high) {
    return range_reader<T>(low, high);
}

template<class T>
struct oneof_reader {
    T operator()(const std::string &s) {
        T ret = default_reader<T>()(s);
        if (std::find(alt.begin(), alt.end(), ret) == alt.end()) {
            throw_cmdline_error("");
        }
        return ret;
    }
    void add(const T &v) {
        alt.push_back(v);
    }

private:
    std::vector<T> alt;
};

template<class T>
oneof_reader<T> oneof(T a1) {
    oneof_reader<T> ret;
    ret.add(a1);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3, T a4) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    ret.add(a4);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3, T a4, T a5) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    ret.add(a4);
    ret.add(a5);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3, T a4, T a5, T a6) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    ret.add(a4);
    ret.add(a5);
    ret.add(a6);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3, T a4, T a5, T a6, T a7) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    ret.add(a4);
    ret.add(a5);
    ret.add(a6);
    ret.add(a7);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3, T a4, T a5, T a6, T a7, T a8) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    ret.add(a4);
    ret.add(a5);
    ret.add(a6);
    ret.add(a7);
    ret.add(a8);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3, T a4, T a5, T a6, T a7, T a8, T a9) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    ret.add(a4);
    ret.add(a5);
    ret.add(a6);
    ret.add(a7);
    ret.add(a8);
    ret.add(a9);
    return ret;
}

template<class T>
oneof_reader<T> oneof(T a1, T a2, T a3, T a4, T a5, T a6, T a7, T a8, T a9, T a10) {
    oneof_reader<T> ret;
    ret.add(a1);
    ret.add(a2);
    ret.add(a3);
    ret.add(a4);
    ret.add(a5);
    ret.add(a6);
    ret.add(a7);
    ret.add(a8);
    ret.add(a9);
    ret.add(a10);
    return ret;
}

//-----

class parser {
public:
    parser() = default;
    ~parser() {
        for (auto &option : options) {
            delete option.second;
        }
    }

    void add(const std::string &name,
             char short_name = 0,
             const std::string &desc = "") {
        if (options.count(name)) {
            throw_cmdline_error("multiple definition: " + name);
        }
        options[name] = new option_without_value(name, short_name, desc);
        ordered.push_back(options[name]);
    }

    template<class T>
    void add(const std::string &name,
             char short_name = 0,
             const std::string &desc = "",
             bool need = true,
             const T def = T()) {
        add(name, short_name, desc, need, def, default_reader<T>());
    }

    template<class T, class F>
    void add(const std::string &name,
             char short_name = 0,
             const std::string &desc = "",
             bool need = true,
             const T def = T(),
             F reader = F()) {
        if (options.count(name)) {
            throw_cmdline_error("multiple definition: " + name);
        }
        options[name] = new option_with_value_with_reader<T, F>(name, short_name, need, def, desc, reader);
        ordered.push_back(options[name]);
    }

    void footer(const std::string &f) {
        ftr = f;
    }

    void set_program_name(const std::string &name) {
        prog_name = name;
    }

    bool exist(const std::string &name) const {
        if (options.count(name) == 0) {
            throw_cmdline_error("there is no flag: --" + name);
        }
        return options.find(name)->second->has_set();
    }

    template<class T>
    const T &get(const std::string &name) const {
        if (options.count(name) == 0) {
            throw_cmdline_error("there is no flag: --" + name);
        }
#ifndef HALIDE_ENABLE_RTTI
        const option_with_value<T> *p = reinterpret_cast<const option_with_value<T> *>(options.find(name)->second);
        return p->get();
#else
        const option_with_value<T> *p = dynamic_cast<const option_with_value<T> *>(options.find(name)->second);
        if (p == nullptr) {
            throw_cmdline_error("type mismatch flag '" + name + "'");
        }
        return p->get();
#endif
    }

    const std::vector<std::string> &rest() const {
        return others;
    }

    bool parse(const std::string &arg) {
        std::vector<std::string> args;

        std::string buf;
        bool in_quote = false;
        for (std::string::size_type i = 0; i < arg.length(); i++) {
            if (arg[i] == '\"') {
                in_quote = !in_quote;
                continue;
            }

            if (arg[i] == ' ' && !in_quote) {
                args.push_back(buf);
                buf = "";
                continue;
            }

            if (arg[i] == '\\') {
                i++;
                if (i >= arg.length()) {
                    errors.emplace_back("unexpected occurrence of '\\' at end of string");
                    return false;
                }
            }

            buf += arg[i];
        }

        if (in_quote) {
            errors.emplace_back("quote is not closed");
            return false;
        }

        if (buf.length() > 0) {
            args.push_back(buf);
        }

        for (auto &arg : args) {
            std::cout << "\"" << arg << "\"" << std::endl;
        }

        return parse(args);
    }

    bool parse(const std::vector<std::string> &args) {
        int argc = static_cast<int>(args.size());
        std::vector<const char *> argv(argc);

        for (int i = 0; i < argc; i++) {
            argv[i] = args[i].c_str();
        }

        return parse(argc, &argv[0]);
    }

    bool parse(int argc, const char *const argv[]) {
        errors.clear();
        others.clear();

        if (argc < 1) {
            errors.emplace_back("argument number must be longer than 0");
            return false;
        }
        if (prog_name.empty()) {
            prog_name = argv[0];
        }

        std::map<char, std::string> lookup;
        for (auto &option : options) {
            if (option.first.length() == 0) {
                continue;
            }
            char initial = option.second->short_name();
            if (initial) {
                if (lookup.count(initial) > 0) {
                    lookup[initial] = "";
                    errors.push_back(std::string("short option '") + initial + "' is ambiguous");
                    return false;
                } else {
                    lookup[initial] = option.first;
                }
            }
        }

        for (int i = 1; i < argc; i++) {
            if (strncmp(argv[i], "--", 2) == 0) {
                const char *p = strchr(argv[i] + 2, '=');
                if (p) {
                    std::string name(argv[i] + 2, p);
                    std::string val(p + 1);
                    set_option(name, val);
                } else {
                    std::string name(argv[i] + 2);
                    if (options.count(name) == 0) {
                        errors.push_back("undefined option: --" + name);
                        continue;
                    }
                    if (options[name]->has_value()) {
                        if (i + 1 >= argc) {
                            errors.push_back("option needs value: --" + name);
                            continue;
                        } else {
                            i++;
                            set_option(name, argv[i]);
                        }
                    } else {
                        set_option(name);
                    }
                }
            } else if (strncmp(argv[i], "-", 1) == 0) {
                if (!argv[i][1]) {
                    continue;
                }
                char last = argv[i][1];
                for (int j = 2; argv[i][j]; j++) {
                    last = argv[i][j];
                    if (lookup.count(argv[i][j - 1]) == 0) {
                        errors.push_back(std::string("undefined short option: -") + argv[i][j - 1]);
                        continue;
                    }
                    if (lookup[argv[i][j - 1]].empty()) {
                        errors.push_back(std::string("ambiguous short option: -") + argv[i][j - 1]);
                        continue;
                    }
                    set_option(lookup[argv[i][j - 1]]);
                }

                if (lookup.count(last) == 0) {
                    errors.push_back(std::string("undefined short option: -") + last);
                    continue;
                }
                if (lookup[last].empty()) {
                    errors.push_back(std::string("ambiguous short option: -") + last);
                    continue;
                }

                if (i + 1 < argc && options[lookup[last]]->has_value()) {
                    set_option(lookup[last], argv[i + 1]);
                    i++;
                } else {
                    set_option(lookup[last]);
                }
            } else {
                others.emplace_back(argv[i]);
            }
        }

        for (auto &option : options) {
            if (!option.second->valid()) {
                errors.push_back("need option: --" + std::string(option.first));
            }
        }

        return errors.empty();
    }

    void parse_check(const std::string &arg) {
        if (!options.count("help")) {
            add("help", '?', "print this message");
        }
        check(0, parse(arg));
    }

    void parse_check(const std::vector<std::string> &args) {
        if (!options.count("help")) {
            add("help", '?', "print this message");
        }
        check(args.size(), parse(args));
    }

    void parse_check(int argc, char *argv[]) {
        if (!options.count("help")) {
            add("help", '?', "print this message");
        }
        check(argc, parse(argc, argv));
    }

    std::string error() const {
        return !errors.empty() ? errors[0] : "";
    }

    std::string error_full() const {
        std::ostringstream oss;
        for (const auto &error : errors) {
            oss << error << std::endl;
        }
        return oss.str();
    }

    std::string usage() const {
        std::ostringstream oss;
        oss << "usage: " << prog_name << " ";
        for (const auto &o : ordered) {
            if (o->must()) {
                oss << o->short_description() << " ";
            }
        }

        oss << "[options] ... " << ftr << std::endl;
        oss << "options:" << std::endl;

        size_t max_width = 0;
        for (const auto &o : ordered) {
            max_width = std::max(max_width, o->name().length());
        }
        for (const auto &o : ordered) {
            if (o->short_name()) {
                oss << "  -" << o->short_name() << ", ";
            } else {
                oss << "      ";
            }

            oss << "--" << o->name();
            for (size_t j = o->name().length(); j < max_width + 4; j++) {
                oss << ' ';
            }
            oss << o->description() << std::endl;
        }
        return oss.str();
    }

private:
    void check(int argc, bool ok) {
        if ((argc == 1 && !ok) || exist("help")) {
            std::cerr << usage();
            exit(0);
        }

        if (!ok) {
            std::cerr << error() << std::endl
                      << usage();
            exit(1);
        }
    }

    void set_option(const std::string &name) {
        if (options.count(name) == 0) {
            errors.push_back("undefined option: --" + name);
            return;
        }
        if (!options[name]->set()) {
            errors.push_back("option needs value: --" + name);
            return;
        }
    }

    void set_option(const std::string &name, const std::string &value) {
        if (options.count(name) == 0) {
            errors.push_back("undefined option: --" + name);
            return;
        }
        if (!options[name]->set(value)) {
            errors.push_back("option value is invalid: --" + name + "=" + value);
            return;
        }
    }

    class option_base {
    public:
        virtual ~option_base() = default;

        virtual bool has_value() const = 0;
        virtual bool set() = 0;
        virtual bool set(const std::string &value) = 0;
        virtual bool has_set() const = 0;
        virtual bool valid() const = 0;
        virtual bool must() const = 0;

        virtual const std::string &name() const = 0;
        virtual char short_name() const = 0;
        virtual const std::string &description() const = 0;
        virtual std::string short_description() const = 0;
    };

    class option_without_value : public option_base {
    public:
        option_without_value(const std::string &name,
                             char short_name,
                             const std::string &desc)
            : nam(name), snam(short_name), desc(desc), has(false) {
        }
        ~option_without_value() override = default;

        bool has_value() const override {
            return false;
        }

        bool set() override {
            has = true;
            return true;
        }

        bool set(const std::string &) override {
            return false;
        }

        bool has_set() const override {
            return has;
        }

        bool valid() const override {
            return true;
        }

        bool must() const override {
            return false;
        }

        const std::string &name() const override {
            return nam;
        }

        char short_name() const override {
            return snam;
        }

        const std::string &description() const override {
            return desc;
        }

        std::string short_description() const override {
            return "--" + nam;
        }

    private:
        std::string nam;
        char snam;
        std::string desc;
        bool has;
    };

    template<class T>
    class option_with_value : public option_base {
    public:
        option_with_value(const std::string &name,
                          char short_name,
                          bool need,
                          const T &def,
                          const std::string &desc)
            : nam(name), snam(short_name), need(need), has(false), def(def), actual(def) {
            this->desc = full_description(desc);
        }
        ~option_with_value() override = default;

        const T &get() const {
            return actual;
        }

        bool has_value() const override {
            return true;
        }

        bool set() override {
            return false;
        }

        bool set(const std::string &value) override {
#ifdef HALIDE_WITH_EXCEPTIONS
            try {
                actual = read(value);
                has = true;
            } catch (const std::exception &e) {
                std::cout << "Exception was caught: " << e.what() << std::endl;
                return false;
            }
            return true;
#else
            actual = read(value);
            has = true;
            return true;
#endif
        }

        bool has_set() const override {
            return has;
        }

        bool valid() const override {
            if (need && !has) {
                return false;
            }
            return true;
        }

        bool must() const override {
            return need;
        }

        const std::string &name() const override {
            return nam;
        }

        char short_name() const override {
            return snam;
        }

        const std::string &description() const override {
            return desc;
        }

        std::string short_description() const override {
            return "--" + nam + "=" + detail::readable_typename<T>();
        }

    protected:
        std::string full_description(const std::string &desc) {
            return desc + " (" + detail::readable_typename<T>() +
                   (need ? "" : " [=" + detail::default_value<T>(def) + "]") + ")";
        }

        virtual T read(const std::string &s) = 0;

        std::string nam;
        char snam;
        bool need;
        std::string desc;

        bool has;
        T def;
        T actual;
    };

    template<class T, class F>
    class option_with_value_with_reader : public option_with_value<T> {
    public:
        option_with_value_with_reader(const std::string &name,
                                      char short_name,
                                      bool need,
                                      const T def,
                                      const std::string &desc,
                                      F reader)
            : option_with_value<T>(name, short_name, need, def, desc), reader(reader) {
        }

    private:
        T read(const std::string &s) override {
            return reader(s);
        }

        F reader;
    };

    std::map<std::string, option_base *> options;
    std::vector<option_base *> ordered;
    std::string ftr;

    std::string prog_name;
    std::vector<std::string> others;

    std::vector<std::string> errors;
};

}  // namespace cmdline
