1 files changed, 137 insertions, 0 deletions
diff --git a/src/win/graph/direct/TextLayout.cpp b/src/win/graph/direct/TextLayout.cpp
new file mode 100644
index 00000000..16db77f0
--- /dev/null
+++ b/src/win/graph/direct/TextLayout.cpp
@@ -0,0 +1,137 @@
+#include "cru/win/graph/direct/TextLayout.hpp"
+
+#include "cru/common/Logger.hpp"
+#include "cru/platform/Check.hpp"
+#include "cru/win/graph/direct/Exception.hpp"
+#include "cru/win/graph/direct/Factory.hpp"
+#include "cru/win/graph/direct/Font.hpp"
+#include "cru/win/String.hpp"
+
+#include <utility>
+
+namespace cru::platform::graph::win::direct {
+using cru::platform::win::IndexUtf16ToUtf8;
+using cru::platform::win::IndexUtf8ToUtf16;
+
+DWriteTextLayout::DWriteTextLayout(DirectGraphFactory* factory,
+                                   std::shared_ptr<IFont> font,
+                                   std::string text)
+    : DirectGraphResource(factory), text_(std::move(text)) {
+  Expects(font);
+  font_ = CheckPlatform<DWriteFont>(font, GetPlatformId());
+
+  w_text_ = cru::platform::win::ToUtf16String(text_);
+
+  ThrowIfFailed(factory->GetDWriteFactory()->CreateTextLayout(
+      w_text_.c_str(), static_cast<UINT32>(w_text_.size()),
+      font_->GetComInterface(), max_width_, max_height_, &text_layout_));
+}
+
+DWriteTextLayout::~DWriteTextLayout() = default;
+
+std::string DWriteTextLayout::GetText() { return text_; }
+
+void DWriteTextLayout::SetText(std::string new_text) {
+  text_.swap(new_text);
+  w_text_ = cru::platform::win::ToUtf16String(text_);
+  ThrowIfFailed(GetDirectFactory()->GetDWriteFactory()->CreateTextLayout(
+      w_text_.c_str(), static_cast<UINT32>(w_text_.size()),
+      font_->GetComInterface(), max_width_, max_height_, &text_layout_));
+}
+
+std::shared_ptr<IFont> DWriteTextLayout::GetFont() {
+  return std::dynamic_pointer_cast<IFont>(font_);
+}
+
+void DWriteTextLayout::SetFont(std::shared_ptr<IFont> font) {
+  font_ = CheckPlatform<DWriteFont>(font, GetPlatformId());
+  ThrowIfFailed(GetDirectFactory()->GetDWriteFactory()->CreateTextLayout(
+      w_text_.c_str(), static_cast<UINT32>(w_text_.size()),
+      font_->GetComInterface(), max_width_, max_height_, &text_layout_));
+}
+
+void DWriteTextLayout::SetMaxWidth(float max_width) {
+  max_width_ = max_width;
+  ThrowIfFailed(text_layout_->SetMaxWidth(max_width_));
+}
+
+void DWriteTextLayout::SetMaxHeight(float max_height) {
+  max_height_ = max_height;
+  ThrowIfFailed(text_layout_->SetMaxHeight(max_height_));
+}
+
+Rect DWriteTextLayout::GetTextBounds() {
+  DWRITE_TEXT_METRICS metrics;
+  ThrowIfFailed(text_layout_->GetMetrics(&metrics));
+  return Rect{metrics.left, metrics.top, metrics.width, metrics.height};
+}
+
+std::vector<Rect> DWriteTextLayout::TextRangeRect(
+    const TextRange& text_range_arg) {
+  if (text_range_arg.count == 0) {
+    return {};
+  }
+  const auto text_range = text_range_arg.Normalize();
+
+  // TODO: This can be faster with one iteration.
+  const int start_index =
+      IndexUtf8ToUtf16(text_, static_cast<int>(text_range.position), w_text_);
+  const int end_index = IndexUtf8ToUtf16(
+      text_, static_cast<int>(text_range.position + text_range.count), w_text_);
+
+  DWRITE_TEXT_METRICS text_metrics;
+  ThrowIfFailed(text_layout_->GetMetrics(&text_metrics));
+  const auto metrics_count =
+      text_metrics.lineCount * text_metrics.maxBidiReorderingDepth;
+
+  std::vector<DWRITE_HIT_TEST_METRICS> hit_test_metrics(metrics_count);
+  UINT32 actual_count;
+  ThrowIfFailed(text_layout_->HitTestTextRange(
+      static_cast<UINT32>(start_index),
+      static_cast<UINT32>(end_index - start_index), 0, 0,
+      hit_test_metrics.data(), metrics_count, &actual_count));
+
+  hit_test_metrics.erase(hit_test_metrics.cbegin() + actual_count,
+                         hit_test_metrics.cend());
+
+  std::vector<Rect> result;
+  result.reserve(actual_count);
+
+  for (const auto& metrics : hit_test_metrics) {
+    result.push_back(
+        Rect{metrics.left, metrics.top, metrics.width, metrics.height});
+  }
+
+  return result;
+}
+
+Point DWriteTextLayout::TextSinglePoint(gsl::index position, bool trailing) {
+  const auto index =
+      IndexUtf8ToUtf16(text_, static_cast<int>(position), w_text_);
+
+  DWRITE_HIT_TEST_METRICS metrics;
+  FLOAT left;
+  FLOAT top;
+  ThrowIfFailed(text_layout_->HitTestTextPosition(static_cast<UINT32>(index),
+                                                  static_cast<BOOL>(trailing),
+                                                  &left, &top, &metrics));
+  return Point{left, top};
+}
+
+TextHitTestResult DWriteTextLayout::HitTest(const Point& point) {
+  BOOL trailing;
+  BOOL inside;
+  DWRITE_HIT_TEST_METRICS metrics;
+
+  ThrowIfFailed(text_layout_->HitTestPoint(point.x, point.y, &trailing, &inside,
+                                           &metrics));
+
+  const auto index =
+      IndexUtf16ToUtf8(w_text_, static_cast<int>(metrics.textPosition), text_);
+  TextHitTestResult result;
+  result.position = index;
+  result.trailing = trailing != 0;
+  result.insideText = inside != 0;
+  return result;
+}
+}  // namespace cru::platform::graph::win::direct