gecko/gfx/thebes/gfxUserFontSet.h

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#ifndef GFX_USER_FONT_SET_H
#define GFX_USER_FONT_SET_H

#include "gfxTypes.h"
#include "gfxFont.h"
#include "gfxFontUtils.h"
#include "nsRefPtrHashtable.h"
#include "nsAutoPtr.h"
#include "nsCOMPtr.h"
#include "nsIURI.h"
#include "nsIFile.h"
#include "nsISupportsImpl.h"

class nsIURI;
class gfxMixedFontFamily;

// parsed CSS @font-face rule information
// lifetime: from when @font-face rule processed until font is loaded
struct gfxFontFaceSrc {
    PRPackedBool           mIsLocal;       // url or local

    // if url, whether to use the origin principal or not
    PRPackedBool           mUseOriginPrincipal;

    // format hint flags, union of all possible formats
    // (e.g. TrueType, EOT, SVG, etc.)
    // see FLAG_FORMAT_* enum values below
    PRUint32               mFormatFlags;

    nsString               mLocalName;     // full font name if local
    nsCOMPtr<nsIURI>       mURI;           // uri if url 
    nsCOMPtr<nsIURI>       mReferrer;      // referrer url if url
    nsCOMPtr<nsISupports>  mOriginPrincipal; // principal if url 
    
};

// subclassed to store platform-specific code cleaned out when font entry is deleted
// lifetime: from when platform font is created until it is deactivated 
class gfxUserFontData {
public:
    gfxUserFontData() { }
    virtual ~gfxUserFontData() { }
};

// initially contains a set of proxy font entry objects, replaced with
// platform/user fonts as downloaded

class gfxMixedFontFamily : public gfxFontFamily {
public:
    friend class gfxUserFontSet;

    gfxMixedFontFamily(const nsAString& aName)
        : gfxFontFamily(aName) { }

    virtual ~gfxMixedFontFamily() { }

    void AddFontEntry(gfxFontEntry *aFontEntry) {
        nsRefPtr<gfxFontEntry> fe = aFontEntry;
        mAvailableFonts.AppendElement(fe);
    }

    void ReplaceFontEntry(gfxFontEntry *aOldFontEntry, gfxFontEntry *aNewFontEntry) 
    {
        PRUint32 numFonts = mAvailableFonts.Length();
        for (PRUint32 i = 0; i < numFonts; i++) {
            gfxFontEntry *fe = mAvailableFonts[i];
            if (fe == aOldFontEntry) {
                mAvailableFonts[i] = aNewFontEntry;
                return;
            }
        }
    }

    void RemoveFontEntry(gfxFontEntry *aFontEntry) 
    {
        PRUint32 numFonts = mAvailableFonts.Length();
        for (PRUint32 i = 0; i < numFonts; i++) {
            gfxFontEntry *fe = mAvailableFonts[i];
            if (fe == aFontEntry) {
                mAvailableFonts.RemoveElementAt(i);
                return;
            }
        }
    }

    // temp method to determine if all proxies are loaded
    PRBool AllLoaded() 
    {
        PRUint32 numFonts = mAvailableFonts.Length();
        for (PRUint32 i = 0; i < numFonts; i++) {
            gfxFontEntry *fe = mAvailableFonts[i];
            if (fe->mIsProxy)
                return PR_FALSE;
        }
        return PR_TRUE;
    }
};

class gfxProxyFontEntry;

class THEBES_API gfxUserFontSet {

public:

    NS_INLINE_DECL_REFCOUNTING(gfxUserFontSet)

    gfxUserFontSet();
    virtual ~gfxUserFontSet();

    enum {
        // no flags ==> no hint set
        // unknown ==> unknown format hint set
        FLAG_FORMAT_UNKNOWN        = 1,
        FLAG_FORMAT_OPENTYPE       = 1 << 1,
        FLAG_FORMAT_TRUETYPE       = 1 << 2,
        FLAG_FORMAT_TRUETYPE_AAT   = 1 << 3,
        FLAG_FORMAT_EOT            = 1 << 4,
        FLAG_FORMAT_SVG            = 1 << 5,
        FLAG_FORMAT_WOFF           = 1 << 6,

        // mask of all unused bits, update when adding new formats
        FLAG_FORMAT_NOT_USED       = ~((1 << 7)-1)
    };

    enum LoadStatus {
        STATUS_LOADING = 0,
        STATUS_LOADED,
        STATUS_FORMAT_NOT_SUPPORTED,
        STATUS_ERROR,
        STATUS_END_OF_LIST
    };


    // add in a font face
    // weight, stretch - 0 == unknown, [1, 9] otherwise
    // italic style = constants in gfxFontConstants.h, e.g. NS_FONT_STYLE_NORMAL
    // TODO: support for unicode ranges not yet implemented
    void AddFontFace(const nsAString& aFamilyName, 
                     const nsTArray<gfxFontFaceSrc>& aFontFaceSrcList, 
                     PRUint32 aWeight = 0, 
                     PRUint32 aStretch = 0, 
                     PRUint32 aItalicStyle = 0, 
                     gfxSparseBitSet *aUnicodeRanges = nsnull);

    // Whether there is a face with this family name
    PRBool HasFamily(const nsAString& aFamilyName) const
    {
        return GetFamily(aFamilyName) != nsnull;
    }

    // lookup a font entry for a given style, returns null if not loaded
    gfxFontEntry *FindFontEntry(const nsAString& aName, 
                                const gfxFontStyle& aFontStyle, 
                                PRBool& aNeedsBold);
                                
    // initialize the process that loads external font data, which upon 
    // completion will call OnLoadComplete method
    virtual nsresult StartLoad(gfxFontEntry *aFontToLoad, 
                               const gfxFontFaceSrc *aFontFaceSrc) = 0;

    // when download has been completed, pass back data here
    // aDownloadStatus == NS_OK ==> download succeeded, error otherwise
    // returns true if platform font creation sucessful (or local()
    // reference was next in line)
    // Ownership of aFontData is passed in here; the font set must
    // ensure that it is eventually deleted with NS_Free().
    PRBool OnLoadComplete(gfxFontEntry *aFontToLoad,
                          const PRUint8 *aFontData, PRUint32 aLength,
                          nsresult aDownloadStatus);

    // generation - each time a face is loaded, generation is
    // incremented so that the change can be recognized 
    PRUint64 GetGeneration() { return mGeneration; }

protected:
    // for a given proxy font entry, attempt to load the next resource
    // in the src list
    LoadStatus LoadNext(gfxProxyFontEntry *aProxyEntry);

    // increment the generation on font load
    void IncrementGeneration();

    gfxMixedFontFamily *GetFamily(const nsAString& aName) const;

    // remove family
    void RemoveFamily(const nsAString& aFamilyName);

    // font families defined by @font-face rules
    nsRefPtrHashtable<nsStringHashKey, gfxMixedFontFamily> mFontFamilies;

    PRUint64        mGeneration;
};

// acts a placeholder until the real font is downloaded

class gfxProxyFontEntry : public gfxFontEntry {
    friend class gfxUserFontSet;

public:
    gfxProxyFontEntry(const nsTArray<gfxFontFaceSrc>& aFontFaceSrcList, 
                      gfxMixedFontFamily *aFamily,
                      PRUint32 aWeight, 
                      PRUint32 aStretch, 
                      PRUint32 aItalicStyle, 
                      gfxSparseBitSet *aUnicodeRanges);

    virtual ~gfxProxyFontEntry();

    virtual gfxFont *CreateFontInstance(const gfxFontStyle *aFontStyle, PRBool aNeedsBold);

    PRPackedBool                           mIsLoading;
    nsTArray<gfxFontFaceSrc>               mSrcList;
    PRUint32                               mSrcIndex; // index of loading src item
};


#endif /* GFX_USER_FONT_SET_H */