1// Copyright 2019 Google LLC.
2#ifndef FontIterator_DEFINED
3#define FontIterator_DEFINED
4
5#include "include/core/SkString.h"
6#include "include/core/SkTypes.h"
7#include "modules/skparagraph/include/TextStyle.h"
8#include "modules/skshaper/include/SkShaper.h"
9#include "src/core/SkSpan.h"
10
11namespace skia {
12namespace textlayout {
13
14class LangIterator final : public SkShaper::LanguageRunIterator {
15public:
16 LangIterator(SkSpan<const char> utf8, SkSpan<Block> styles, const TextStyle& defaultStyle)
17 : fText(utf8)
18 , fTextStyles(styles)
19 , fCurrentChar(utf8.begin())
20 , fCurrentStyle(fTextStyles.begin())
21 , fCurrentLocale(defaultStyle.getLocale()) {}
22
23 void consume() override {
24 SkASSERT(fCurrentChar < fText.end());
25
26 if (fCurrentStyle == fTextStyles.end()) {
27 fCurrentChar = fText.end();
28 return;
29 }
30
31 fCurrentChar = fText.begin() + fCurrentStyle->fRange.end;
32 fCurrentLocale = fCurrentStyle->fStyle.getLocale();
33 while (++fCurrentStyle != fTextStyles.end() && !fCurrentStyle->fStyle.isPlaceholder()) {
34 if (fCurrentStyle->fStyle.getLocale() != fCurrentLocale) {
35 break;
36 }
37 fCurrentChar = fText.begin() + fCurrentStyle->fRange.end;
38 }
39 }
40
41 size_t endOfCurrentRun() const override { return fCurrentChar - fText.begin(); }
42 bool atEnd() const override { return fCurrentChar >= fText.end(); }
43 const char* currentLanguage() const override { return fCurrentLocale.c_str(); }
44
45private:
46 SkSpan<const char> fText;
47 SkSpan<Block> fTextStyles;
48 const char* fCurrentChar;
49 Block* fCurrentStyle;
50 SkString fCurrentLocale;
51};
52} // namespace textlayout
53} // namespace skia
54
55#endif // FontIterator_DEFINED
56