Plan depth export through document renderer

src/app_core/document_export.h

@@ -37,10 +37,20 @@ struct DocumentCubeFaceExportTarget {
     std::size_t face_count = 0;
 };
 
+struct DocumentDepthExportTarget {
+    std::string image_path;
+    std::string depth_path;
+};
+
 struct DocumentCubeFaceExportPayload {
     std::span<const std::byte> bytes;
 };
 
+struct DocumentDepthExportPayload {
+    std::span<const std::byte> image_bytes;
+    std::span<const std::byte> depth_bytes;
+};
+
 struct DocumentExportCollectionPngPayload {
     std::string path_suffix;
     std::span<const std::byte> bytes;
@@ -195,6 +205,16 @@ public:
     virtual void publish_exported_image(std::string_view path) = 0;
 };
 
+class DocumentDepthExportWriteServices {
+public:
+    virtual ~DocumentDepthExportWriteServices() = default;
+
+    virtual pp::foundation::Status write_binary_file(
+        std::string_view path,
+        std::span<const std::byte> bytes) = 0;
+    virtual void publish_exported_image(std::string_view path) = 0;
+};
+
 class DocumentExportCollectionWriteServices {
 public:
     virtual ~DocumentExportCollectionWriteServices() = default;
@@ -623,6 +643,34 @@ document_cube_face_export_names() noexcept
     return pp::foundation::Result<DocumentCubeFaceExportTarget>::success(std::move(target));
 }
 
+[[nodiscard]] inline pp::foundation::Result<DocumentDepthExportTarget> make_document_depth_export_target(
+    std::string_view work_directory,
+    std::string_view document_name)
+{
+    if (work_directory.empty()) {
+        return pp::foundation::Result<DocumentDepthExportTarget>::failure(
+            pp::foundation::Status::invalid_argument("work directory must not be empty"));
+    }
+
+    if (document_name.empty()) {
+        return pp::foundation::Result<DocumentDepthExportTarget>::failure(
+            pp::foundation::Status::invalid_argument("document name must not be empty"));
+    }
+
+    DocumentDepthExportTarget target;
+    target.image_path.reserve(work_directory.size() + document_name.size() + 5U);
+    target.image_path += work_directory;
+    target.image_path += "/";
+    target.image_path += document_name;
+    target.image_path += ".png";
+    target.depth_path.reserve(work_directory.size() + document_name.size() + 11U);
+    target.depth_path += work_directory;
+    target.depth_path += "/";
+    target.depth_path += document_name;
+    target.depth_path += "_depth.png";
+    return pp::foundation::Result<DocumentDepthExportTarget>::success(std::move(target));
+}
+
 [[nodiscard]] inline std::string document_export_two_digit_index(std::size_t index)
 {
     auto value = std::to_string(index);
@@ -706,6 +754,33 @@ document_cube_face_export_names() noexcept
     return pp::foundation::Status::success();
 }
 
+[[nodiscard]] inline pp::foundation::Status execute_document_depth_export_write(
+    const DocumentDepthExportTarget& target,
+    DocumentDepthExportPayload payload,
+    DocumentDepthExportWriteServices& services)
+{
+    if (target.image_path.empty() || target.depth_path.empty()) {
+        return pp::foundation::Status::invalid_argument("depth export target requires image and depth paths");
+    }
+    if (payload.image_bytes.empty() || payload.depth_bytes.empty()) {
+        return pp::foundation::Status::invalid_argument("depth export payload requires image and depth bytes");
+    }
+
+    const auto image_status = services.write_binary_file(target.image_path, payload.image_bytes);
+    if (!image_status.ok()) {
+        return image_status;
+    }
+    services.publish_exported_image(target.image_path);
+
+    const auto depth_status = services.write_binary_file(target.depth_path, payload.depth_bytes);
+    if (!depth_status.ok()) {
+        return depth_status;
+    }
+    services.publish_exported_image(target.depth_path);
+
+    return pp::foundation::Status::success();
+}
+
 [[nodiscard]] inline pp::foundation::Status execute_document_export_collection_write(
     const DocumentExportCollectionTarget& target,
     std::span<const DocumentExportCollectionPngPayload> payloads,