#pragma once

#include <cstdint>
#include <iterator>
#include <memory>
#include <string>
#include <type_traits>
#include <variant>
#include <vector>

#define NOMINMAX
// %TwinCAT3DIR%\sdk\Include
#include <Ads.h>
namespace tcAdsAPI
{
// <TcAdsDef.h> defines many of the same types as <Ads.h> so we move these into another namespace,
// functions in <TcAdsAPI.h> have external "C" linkange so linking is not affected
#include <TcAdsDef.h>
#include <TcAdsAPI.h>
}

enum class adsDatatypeId : std::uint16_t
{
    void_ = VT_EMPTY,
    int8_ = VT_I1,
    uint8_ = VT_UI1,
    int16_ = VT_I2,
    uint16_ = VT_UI2,
    int32_ = VT_I4,
    uint32_ = VT_UI4,
    int64_ = VT_I8,
    uint64_ = VT_UI8,
    float_ = VT_R4,
    double_ = VT_R8,
    cstring_ = VT_LPSTR,
    wcstring_ = VT_LPWSTR,
    ldouble_ = VT_LPWSTR + 1,
    bool_ = 33,
    blob_ = VT_BLOB,
};

using ustring = std::basic_string<std::uint8_t>;

class adsVarData;

class adsData
{
public:
    using sizeType = decltype(AdsSymbolEntry::entryLength);

    class symbolInfo;
    class subSymbolInfo;
    class datatypeInfo;
    class arrayInfo;
    using attributeInfo = std::pair<std::string, std::string>;
    using enumVariant = std::variant<std::int8_t, std::uint8_t,
                                     std::int16_t, std::uint16_t,
                                     std::int32_t, std::uint32_t,
                                     std::int64_t, std::uint64_t,
                                     std::float_t, std::double_t,
                                     bool, std::string>;
    class enumInfo : public std::pair<std::string, enumVariant>
    {
    public:
        using pair_type = std::pair<std::string, enumVariant>;
        using pair_type::pair_type;
        std::string valueToString() const;
    };

    class iterator;
    using const_iterator = iterator;

    explicit adsData(decltype(AmsAddr::port) port = AMSPORT_R0_PLC_RTS1);

    adsData(const adsData&) = delete;
    adsData& operator=(const adsData&) = delete;

    adsData(adsData&&) noexcept;
    adsData& operator=(adsData&&) noexcept;

    ~adsData() noexcept;

    adsVarData operator[](std::string_view name) const;

    iterator begin() const noexcept;
    iterator end() const noexcept;
    iterator cbegin() const noexcept;
    iterator cend() const noexcept;
private:
    void initialize(const std::vector<char>& symData, const std::vector<char>& dtData);
    std::vector<symbolInfo> symbols_;
    std::vector<datatypeInfo> types_;
};

class adsVarData
{
public:
    using sizeType = adsData::sizeType;
    class iterator;
    using const_iterator = iterator;

    std::string        name(std::string prefix) const;
    std::string        shortName() const;
    const std::string& type() const noexcept;
    const std::string& comment() const noexcept;
    adsDatatypeId      typeId() const noexcept;
    sizeType           group() const noexcept;
    sizeType           offset() const noexcept;
    sizeType           size() const noexcept;
    bool               isStatic() const noexcept;
    const GUID*        typeGuid() const noexcept;
    const ustring&     copyMask() const noexcept;
    const std::vector<adsData::attributeInfo>& attributes() const noexcept;
    const std::vector<adsData::attributeInfo>& typeAttributes() const noexcept;
    const std::vector<adsData::enumInfo>& typeEnums() const noexcept;

    bool isScalar() const noexcept;
    bool isPointer() const noexcept;
    bool isArray() const noexcept;
    bool isStruct() const noexcept;
    bool empty() const noexcept;

    sizeType subElements() const noexcept;

    iterator begin() const noexcept;
    iterator end() const noexcept;
    iterator cbegin() const noexcept;
    iterator cend() const noexcept;
private:
    adsVarData(const adsData::subSymbolInfo* info, sizeType group, sizeType offset, sizeType index);
    const adsData::subSymbolInfo* info_;
    sizeType group_;
    sizeType offset_;
    sizeType index_;

    friend class adsData;
    friend class adsData::iterator;
};

class adsData::iterator
{
public:
    using value_type = adsVarData;
    using reference = adsVarData;
    using pointer = adsVarData;
    using difference_type = std::ptrdiff_t;
    using iterator_category = std::input_iterator_tag;

    reference operator*() const noexcept;
    pointer operator->() const noexcept;

    friend bool operator==(iterator lhs, iterator rhs) noexcept;
    friend bool operator!=(iterator lhs, iterator rhs) noexcept;

    iterator& operator++() noexcept;
    iterator operator++(int) noexcept;
private:
    explicit iterator(std::vector<adsData::symbolInfo>::const_iterator it) noexcept;
    std::vector<adsData::symbolInfo>::const_iterator iter_;

    friend class adsData;
};

class adsVarData::iterator
{
public:
    using value_type = adsVarData;
    using reference = adsVarData;
    using pointer = adsVarData;
    using difference_type = std::ptrdiff_t;
    using iterator_category = std::input_iterator_tag;

    reference operator*() const noexcept;
    pointer operator->() const noexcept;

    friend bool operator==(const iterator& lhs, const iterator& rhs) noexcept;
    friend bool operator!=(const iterator& lhs, const iterator& rhs) noexcept;

    iterator& operator++() noexcept;
    iterator operator++(int) noexcept;
private:
    explicit iterator(const adsData::subSymbolInfo* info, sizeType group, sizeType offset, sizeType index) noexcept;
    const adsData::subSymbolInfo* info_;
    sizeType group_;
    sizeType offset_;
    sizeType index_;

    friend class adsVarData;
};