michael@0: /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef GFX_DWRITETEXTANALYSIS_H
michael@0: #define GFX_DWRITETEXTANALYSIS_H
michael@0: 
michael@0: #include "gfxDWriteCommon.h"
michael@0: 
michael@0: // Helper source/sink class for text analysis.
michael@0: class TextAnalysis
michael@0:     :   public IDWriteTextAnalysisSource,
michael@0:         public IDWriteTextAnalysisSink        
michael@0: {
michael@0: public:
michael@0: 
michael@0:     // IUnknown interface
michael@0:     IFACEMETHOD(QueryInterface)(IID const& iid, OUT void** ppObject)
michael@0:     {
michael@0:         if (iid == __uuidof(IDWriteTextAnalysisSource)) {
michael@0:             *ppObject = static_cast<IDWriteTextAnalysisSource*>(this);
michael@0:             return S_OK;
michael@0:         } else if (iid == __uuidof(IDWriteTextAnalysisSink)) {
michael@0:             *ppObject = static_cast<IDWriteTextAnalysisSink*>(this);
michael@0:             return S_OK;
michael@0:         } else if (iid == __uuidof(IUnknown)) {
michael@0:             *ppObject = 
michael@0:                 static_cast<IUnknown*>(static_cast<IDWriteTextAnalysisSource*>(this));
michael@0:             return S_OK;
michael@0:         } else {
michael@0:             return E_NOINTERFACE;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     IFACEMETHOD_(ULONG, AddRef)()
michael@0:     {
michael@0:         return 1;
michael@0:     }
michael@0: 
michael@0:     IFACEMETHOD_(ULONG, Release)()
michael@0:     {
michael@0:         return 1;
michael@0:     }
michael@0: 
michael@0:     // A single contiguous run of characters containing the same analysis 
michael@0:     // results.
michael@0:     struct Run
michael@0:     {
michael@0:         UINT32 mTextStart;   // starting text position of this run
michael@0:         UINT32 mTextLength;  // number of contiguous code units covered
michael@0:         UINT32 mGlyphStart;  // starting glyph in the glyphs array
michael@0:         UINT32 mGlyphCount;  // number of glyphs associated with this run of 
michael@0:                              // text
michael@0:         DWRITE_SCRIPT_ANALYSIS mScript;
michael@0:         UINT8 mBidiLevel;
michael@0:         bool mIsSideways;
michael@0: 
michael@0:         inline bool ContainsTextPosition(UINT32 aTextPosition) const
michael@0:         {
michael@0:             return aTextPosition >= mTextStart
michael@0:                 && aTextPosition <  mTextStart + mTextLength;
michael@0:         }
michael@0: 
michael@0:         Run *nextRun;
michael@0:     };
michael@0: 
michael@0: public:
michael@0:     TextAnalysis(const wchar_t* text,
michael@0:                  UINT32 textLength,
michael@0:                  const wchar_t* localeName,
michael@0:                  DWRITE_READING_DIRECTION readingDirection);
michael@0: 
michael@0:     ~TextAnalysis();
michael@0: 
michael@0:     STDMETHODIMP GenerateResults(IDWriteTextAnalyzer* textAnalyzer,
michael@0:                                  Run **runHead);
michael@0: 
michael@0:     // IDWriteTextAnalysisSource implementation
michael@0: 
michael@0:     IFACEMETHODIMP GetTextAtPosition(UINT32 textPosition,
michael@0:                                      OUT WCHAR const** textString,
michael@0:                                      OUT UINT32* textLength);
michael@0: 
michael@0:     IFACEMETHODIMP GetTextBeforePosition(UINT32 textPosition,
michael@0:                                          OUT WCHAR const** textString,
michael@0:                                          OUT UINT32* textLength);
michael@0: 
michael@0:     IFACEMETHODIMP_(DWRITE_READING_DIRECTION) 
michael@0:         GetParagraphReadingDirection() throw();
michael@0: 
michael@0:     IFACEMETHODIMP GetLocaleName(UINT32 textPosition,
michael@0:                                  OUT UINT32* textLength,
michael@0:                                  OUT WCHAR const** localeName);
michael@0: 
michael@0:     IFACEMETHODIMP 
michael@0:         GetNumberSubstitution(UINT32 textPosition,
michael@0:                               OUT UINT32* textLength,
michael@0:                               OUT IDWriteNumberSubstitution** numberSubstitution);
michael@0: 
michael@0:     // IDWriteTextAnalysisSink implementation
michael@0: 
michael@0:     IFACEMETHODIMP 
michael@0:         SetScriptAnalysis(UINT32 textPosition,
michael@0:                           UINT32 textLength,
michael@0:                           DWRITE_SCRIPT_ANALYSIS const* scriptAnalysis);
michael@0: 
michael@0:     IFACEMETHODIMP 
michael@0:         SetLineBreakpoints(UINT32 textPosition,
michael@0:                            UINT32 textLength,
michael@0:                            const DWRITE_LINE_BREAKPOINT* lineBreakpoints);
michael@0: 
michael@0:     IFACEMETHODIMP SetBidiLevel(UINT32 textPosition,
michael@0:                                 UINT32 textLength,
michael@0:                                 UINT8 explicitLevel,
michael@0:                                 UINT8 resolvedLevel);
michael@0: 
michael@0:     IFACEMETHODIMP 
michael@0:         SetNumberSubstitution(UINT32 textPosition,
michael@0:                               UINT32 textLength,
michael@0:                               IDWriteNumberSubstitution* numberSubstitution);
michael@0: 
michael@0: protected:
michael@0:     Run *FetchNextRun(IN OUT UINT32* textLength);
michael@0: 
michael@0:     void SetCurrentRun(UINT32 textPosition);
michael@0: 
michael@0:     void SplitCurrentRun(UINT32 splitPosition);
michael@0: 
michael@0: protected:
michael@0:     // Input
michael@0:     // (weak references are fine here, since this class is a transient
michael@0:     //  stack-based helper that doesn't need to copy data)
michael@0:     UINT32 mTextLength;
michael@0:     const wchar_t* mText;
michael@0:     const wchar_t* mLocaleName;
michael@0:     DWRITE_READING_DIRECTION mReadingDirection;
michael@0: 
michael@0:     // Current processing state.
michael@0:     Run *mCurrentRun;
michael@0: 
michael@0:     // Output is a list of runs starting here
michael@0:     Run  mRunHead;
michael@0: };
michael@0: 
michael@0: #endif /* GFX_DWRITETEXTANALYSIS_H */