/*++
Copyright (c) Microsoft Corporation
Licensed under the MIT license.

Module Name:
- UiaTextRangeBase.hpp

Abstract:
- This module provides UI Automation access to the text of the console
  window to support both automation tests and accessibility (screen
  reading) applications.
- ConHost and Windows Terminal must implement their own virtual functions separately.

Author(s):
- Austin Diviness (AustDi)     2017
- Carlos Zamora   (CaZamor)    2019
--*/

#pragma once

#include "inc/viewport.hpp"
#include "../buffer/out/textBuffer.hpp"
#include "IUiaData.h"
#include "unicode.hpp"
#include "IUiaTraceable.h"

#include <UIAutomationCore.h>
#include <deque>
#include <tuple>
#include <wrl/implements.h>

#ifdef UNIT_TESTING
class UiaTextRangeTests;
#endif

namespace Microsoft::Console::Types
{
    class UiaTextRangeBase : public WRL::RuntimeClass<WRL::RuntimeClassFlags<WRL::ClassicCom | WRL::InhibitFtmBase>, ITextRangeProvider>, public IUiaTraceable
    {
    protected:
        // indicates which direction a movement operation
        // is going
        enum class MovementDirection
        {
            Forward,
            Backward
        };

    public:
        // The default word delimiter for UiaTextRanges
        static constexpr std::wstring_view DefaultWordDelimiter{ &UNICODE_SPACE, 1 };

        // degenerate range
        virtual HRESULT RuntimeClassInitialize(_In_ IUiaData* pData,
                                               _In_ IRawElementProviderSimple* const pProvider,
                                               _In_ std::wstring_view wordDelimiters = DefaultWordDelimiter) noexcept;

        // degenerate range at cursor position
        virtual HRESULT RuntimeClassInitialize(_In_ IUiaData* pData,
                                               _In_ IRawElementProviderSimple* const pProvider,
                                               _In_ const Cursor& cursor,
                                               _In_ std::wstring_view wordDelimiters = DefaultWordDelimiter) noexcept;

        // specific endpoint range
        virtual HRESULT RuntimeClassInitialize(_In_ IUiaData* pData,
                                               _In_ IRawElementProviderSimple* const pProvider,
                                               _In_ const COORD start,
                                               _In_ const COORD end,
                                               _In_ bool blockRange = false,
                                               _In_ std::wstring_view wordDelimiters = DefaultWordDelimiter) noexcept;

        virtual HRESULT RuntimeClassInitialize(const UiaTextRangeBase& a) noexcept;

        UiaTextRangeBase(const UiaTextRangeBase&) = delete;
        UiaTextRangeBase(UiaTextRangeBase&&) = delete;
        UiaTextRangeBase& operator=(const UiaTextRangeBase&) = delete;
        UiaTextRangeBase& operator=(UiaTextRangeBase&&) = delete;
        ~UiaTextRangeBase() = default;

        const COORD GetEndpoint(TextPatternRangeEndpoint endpoint) const noexcept;
        bool SetEndpoint(TextPatternRangeEndpoint endpoint, const COORD val) noexcept;
        const bool IsDegenerate() const noexcept;

        // ITextRangeProvider methods
        virtual IFACEMETHODIMP Clone(_Outptr_result_maybenull_ ITextRangeProvider** ppRetVal) = 0;
        IFACEMETHODIMP Compare(_In_opt_ ITextRangeProvider* pRange, _Out_ BOOL* pRetVal) noexcept override;
        IFACEMETHODIMP CompareEndpoints(_In_ TextPatternRangeEndpoint endpoint,
                                        _In_ ITextRangeProvider* pTargetRange,
                                        _In_ TextPatternRangeEndpoint targetEndpoint,
                                        _Out_ int* pRetVal) noexcept override;
        IFACEMETHODIMP ExpandToEnclosingUnit(_In_ TextUnit unit) noexcept override;
        IFACEMETHODIMP FindAttribute(_In_ TEXTATTRIBUTEID textAttributeId,
                                     _In_ VARIANT val,
                                     _In_ BOOL searchBackward,
                                     _Outptr_result_maybenull_ ITextRangeProvider** ppRetVal) noexcept override;
        IFACEMETHODIMP FindText(_In_ BSTR text,
                                _In_ BOOL searchBackward,
                                _In_ BOOL ignoreCase,
                                _Outptr_result_maybenull_ ITextRangeProvider** ppRetVal) noexcept override;
        IFACEMETHODIMP GetAttributeValue(_In_ TEXTATTRIBUTEID textAttributeId,
                                         _Out_ VARIANT* pRetVal) noexcept override;
        IFACEMETHODIMP GetBoundingRectangles(_Outptr_result_maybenull_ SAFEARRAY** ppRetVal) noexcept override;
        IFACEMETHODIMP GetEnclosingElement(_Outptr_result_maybenull_ IRawElementProviderSimple** ppRetVal) noexcept override;
        IFACEMETHODIMP GetText(_In_ int maxLength,
                               _Out_ BSTR* pRetVal) noexcept override;
        IFACEMETHODIMP Move(_In_ TextUnit unit,
                            _In_ int count,
                            _Out_ int* pRetVal) noexcept override;
        IFACEMETHODIMP MoveEndpointByUnit(_In_ TextPatternRangeEndpoint endpoint,
                                          _In_ TextUnit unit,
                                          _In_ int count,
                                          _Out_ int* pRetVal) noexcept override;
        IFACEMETHODIMP MoveEndpointByRange(_In_ TextPatternRangeEndpoint endpoint,
                                           _In_ ITextRangeProvider* pTargetRange,
                                           _In_ TextPatternRangeEndpoint targetEndpoint) noexcept override;
        IFACEMETHODIMP Select() noexcept override;
        IFACEMETHODIMP AddToSelection() noexcept override;
        IFACEMETHODIMP RemoveFromSelection() noexcept override;
        IFACEMETHODIMP ScrollIntoView(_In_ BOOL alignToTop) noexcept override;
        IFACEMETHODIMP GetChildren(_Outptr_result_maybenull_ SAFEARRAY** ppRetVal) noexcept override;

    protected:
        UiaTextRangeBase() = default;
        IUiaData* _pData{ nullptr };

        IRawElementProviderSimple* _pProvider{ nullptr };

        std::wstring _wordDelimiters{};

        virtual void _TranslatePointToScreen(LPPOINT clientPoint) const = 0;
        virtual void _TranslatePointFromScreen(LPPOINT screenPoint) const = 0;

        void Initialize(_In_ const UiaPoint point);

        // measure units in the form [_start, _end).
        // These are in the TextBuffer coordinate space.
        // NOTE: _start is inclusive, but _end is exclusive
        COORD _start{};
        COORD _end{};
        bool _blockRange{};

        // This is used by tracing to extract the text value
        // that the UiaTextRange currently encompasses.
        // GetText() cannot be used as it's not const
        std::wstring _getTextValue(std::optional<unsigned int> maxLength = std::nullopt) const;

        RECT _getTerminalRect() const;

        virtual const COORD _getScreenFontSize() const;

        const unsigned int _getViewportHeight(const SMALL_RECT viewport) const noexcept;
        const Viewport _getOptimizedBufferSize() const noexcept;
        const til::point _getDocumentEnd() const;

        void _getBoundingRect(const til::rectangle textRect, _Inout_ std::vector<double>& coords) const;

        void _expandToEnclosingUnit(TextUnit unit);

        void
        _moveEndpointByUnitCharacter(_In_ const int moveCount,
                                     _In_ const TextPatternRangeEndpoint endpoint,
                                     gsl::not_null<int*> const pAmountMoved,
                                     _In_ const bool preventBufferEnd = false);

        void
        _moveEndpointByUnitWord(_In_ const int moveCount,
                                _In_ const TextPatternRangeEndpoint endpoint,
                                gsl::not_null<int*> const pAmountMoved,
                                _In_ const bool preventBufferEnd = false);

        void
        _moveEndpointByUnitLine(_In_ const int moveCount,
                                _In_ const TextPatternRangeEndpoint endpoint,
                                gsl::not_null<int*> const pAmountMoved,
                                _In_ const bool preventBoundary = false) noexcept;

        void
        _moveEndpointByUnitDocument(_In_ const int moveCount,
                                    _In_ const TextPatternRangeEndpoint endpoint,
                                    gsl::not_null<int*> const pAmountMoved,
                                    _In_ const bool preventBoundary = false) noexcept;

        std::optional<bool> _verifyAttr(TEXTATTRIBUTEID attributeId, VARIANT val, const TextAttribute& attr) const;
        bool _initializeAttrQuery(TEXTATTRIBUTEID attributeId, VARIANT* pRetVal, const TextAttribute& attr) const;
        bool _tryMoveToWordStart(const TextBuffer& buffer, const til::point documentEnd, COORD& resultingPos) const;

        COORD _getInclusiveEnd() noexcept;

#ifdef UNIT_TESTING
        friend class ::UiaTextRangeTests;
#endif
        friend class UiaTracing;
    };
}