LibPDF: Split ColorSpace into a different class for each color space

While unnecessary at the moment, this will allow for more fine-grained
control when complex color spaces get added.

7 files changed, 174 insertions, 106 deletions

diff --git a/Userland/Libraries/LibPDF/CMakeLists.txt b/Userland/Libraries/LibPDF/CMakeLists.txt
index ea1cbce233..c3a959e4b2 100644
--- a/Userland/Libraries/LibPDF/CMakeLists.txt
+++ b/Userland/Libraries/LibPDF/CMakeLists.txt
@@ -1,4 +1,5 @@
 set(SOURCES
+    ColorSpace.cpp
     CommonNames.cpp
     Document.cpp
     Filter.cpp
diff --git a/Userland/Libraries/LibPDF/ColorSpace.cpp b/Userland/Libraries/LibPDF/ColorSpace.cpp
new file mode 100644
index 0000000000..1651c3fff8
--- /dev/null
+++ b/Userland/Libraries/LibPDF/ColorSpace.cpp
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2021, Matthew Olsson <mattco@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibPDF/ColorSpace.h>
+#include <LibPDF/CommonNames.h>
+
+namespace PDF {
+
+RefPtr<DeviceGrayColorSpace> DeviceGrayColorSpace::the()
+{
+    static auto instance = adopt_ref(*new DeviceGrayColorSpace());
+    return instance;
+}
+
+Color DeviceGrayColorSpace::color(const Vector<Value>& arguments) const
+{
+    VERIFY(arguments.size() == 1);
+    auto gray = static_cast<u8>(arguments[0].to_float() * 255.0f);
+    return Color(gray, gray, gray);
+}
+
+RefPtr<DeviceRGBColorSpace> DeviceRGBColorSpace::the()
+{
+    static auto instance = adopt_ref(*new DeviceRGBColorSpace());
+    return instance;
+}
+
+Color DeviceRGBColorSpace::color(const Vector<Value>& arguments) const
+{
+    VERIFY(arguments.size() == 3);
+    auto r = static_cast<u8>(arguments[0].to_float() * 255.0f);
+    auto g = static_cast<u8>(arguments[1].to_float() * 255.0f);
+    auto b = static_cast<u8>(arguments[2].to_float() * 255.0f);
+    return Color(r, g, b);
+}
+
+RefPtr<DeviceCMYKColorSpace> DeviceCMYKColorSpace::the()
+{
+    static auto instance = adopt_ref(*new DeviceCMYKColorSpace());
+    return instance;
+}
+
+Color DeviceCMYKColorSpace::color(const Vector<Value>& arguments) const
+{
+    VERIFY(arguments.size() == 4);
+    auto c = arguments[0].to_float();
+    auto m = arguments[1].to_float();
+    auto y = arguments[2].to_float();
+    auto k = arguments[3].to_float();
+    return Color::from_cmyk(c, m, y, k);
+}
+
+}
diff --git a/Userland/Libraries/LibPDF/ColorSpace.h b/Userland/Libraries/LibPDF/ColorSpace.h
new file mode 100644
index 0000000000..cea624a6ac
--- /dev/null
+++ b/Userland/Libraries/LibPDF/ColorSpace.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2021, Matthew Olsson <mattco@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/FlyString.h>
+#include <LibGfx/Color.h>
+#include <LibPDF/Object.h>
+#include <LibPDF/Value.h>
+
+#define ENUMERATE_COLOR_SPACES(V) \
+    V(DeviceGray)                 \
+    V(DeviceRGB)                  \
+    V(DeviceCMYK)                 \
+    V(CalGray)                    \
+    V(CalRGB)                     \
+    V(Lab)                        \
+    V(ICCBased)                   \
+    V(Indexed)                    \
+    V(Pattern)                    \
+    V(Separation)                 \
+    V(DeviceN)
+
+namespace PDF {
+
+class ColorSpace : public RefCounted<ColorSpace> {
+public:
+    virtual ~ColorSpace() = default;
+
+    virtual Color color(const Vector<Value>& arguments) const = 0;
+};
+
+class DeviceGrayColorSpace final : public ColorSpace {
+public:
+    static RefPtr<DeviceGrayColorSpace> the();
+
+    virtual ~DeviceGrayColorSpace() override = default;
+
+    virtual Color color(const Vector<Value>& arguments) const override;
+
+private:
+    DeviceGrayColorSpace() = default;
+};
+
+class DeviceRGBColorSpace final : public ColorSpace {
+public:
+    static RefPtr<DeviceRGBColorSpace> the();
+
+    virtual ~DeviceRGBColorSpace() override = default;
+
+    virtual Color color(const Vector<Value>& arguments) const override;
+
+private:
+    DeviceRGBColorSpace() = default;
+};
+
+class DeviceCMYKColorSpace final : public ColorSpace {
+public:
+    static RefPtr<DeviceCMYKColorSpace> the();
+
+    virtual ~DeviceCMYKColorSpace() override = default;
+
+    virtual Color color(const Vector<Value>& arguments) const override;
+
+private:
+    DeviceCMYKColorSpace() = default;
+};
+
+}
diff --git a/Userland/Libraries/LibPDF/CommonNames.h b/Userland/Libraries/LibPDF/CommonNames.h
index fe4010dc7e..b300c81396 100644
--- a/Userland/Libraries/LibPDF/CommonNames.h
+++ b/Userland/Libraries/LibPDF/CommonNames.h
@@ -12,14 +12,20 @@
     V(ASCII85Decode)              \
     V(ASCIIHexDecode)             \
     V(BaseFont)                   \
+    V(BlackPoint)                 \
     V(C)                          \
+    V(CalRGB)                     \
     V(CCITTFaxDecode)             \
+    V(ColorSpace)                 \
     V(Contents)                   \
     V(Count)                      \
     V(CropBox)                    \
     V(Crypt)                      \
     V(DCTDecode)                  \
     V(Dest)                       \
+    V(DeviceCMYK)                 \
+    V(DeviceGray)                 \
+    V(DeviceRGB)                  \
     V(E)                          \
     V(F)                          \
     V(Filter)                     \
@@ -33,6 +39,7 @@
     V(FitV)                       \
     V(FlateDecode)                \
     V(Font)                       \
+    V(Gamma)                      \
     V(H)                          \
     V(JBIG2Decode)                \
     V(JPXDecode)                  \
@@ -42,6 +49,7 @@
     V(Last)                       \
     V(Length)                     \
     V(Linearized)                 \
+    V(Matrix)                     \
     V(MediaBox)                   \
     V(N)                          \
     V(Next)                       \
@@ -50,6 +58,7 @@
     V(P)                          \
     V(Pages)                      \
     V(Parent)                     \
+    V(Pattern)                    \
     V(Prev)                       \
     V(Resources)                  \
     V(Root)                       \
@@ -59,6 +68,7 @@
     V(Title)                      \
     V(Type)                       \
     V(UserUnit)                   \
+    V(WhitePoint)                 \
     V(XYZ)
 
 namespace PDF {
diff --git a/Userland/Libraries/LibPDF/Document.cpp b/Userland/Libraries/LibPDF/Document.cpp
index a127a4359f..c545e781dd 100644
--- a/Userland/Libraries/LibPDF/Document.cpp
+++ b/Userland/Libraries/LibPDF/Document.cpp
@@ -89,6 +89,11 @@ Page Document::get_page(u32 index)
     auto page_object_index = m_page_object_indices[index];
     auto raw_page_object = resolve_to<DictObject>(get_or_load_value(page_object_index));
 
+    if (!raw_page_object->contains(CommonNames::Resources)) {
+        // This page inherits its resource dictionary
+        TODO();
+    }
+
     auto resources = raw_page_object->get_dict(this, CommonNames::Resources);
     auto contents = raw_page_object->get_object(this, CommonNames::Contents);
 
diff --git a/Userland/Libraries/LibPDF/Renderer.cpp b/Userland/Libraries/LibPDF/Renderer.cpp
index a0de5c37f9..009b660d06 100644
--- a/Userland/Libraries/LibPDF/Renderer.cpp
+++ b/Userland/Libraries/LibPDF/Renderer.cpp
@@ -7,8 +7,6 @@
 #include <AK/Utf8View.h>
 #include <LibPDF/CommonNames.h>
 #include <LibPDF/Renderer.h>
-#include <ctype.h>
-#include <math.h>
 
 #define RENDERER_HANDLER(name) \
     void Renderer::handle_##name([[maybe_unused]] const Vector<Value>& args)
@@ -22,58 +20,6 @@
 
 namespace PDF {
 
-Optional<ColorSpace::Type> ColorSpace::color_space_from_string(const FlyString& str)
-{
-#define ENUM(name)    \
-    if (str == #name) \
-        return ColorSpace::Type::name;
-    ENUMERATE_COLOR_SPACES(ENUM)
-#undef ENUM
-
-    return {};
-}
-
-Color ColorSpace::default_color_for_color_space(ColorSpace::Type color_space)
-{
-    switch (color_space) {
-    case Type::DeviceGray:
-    case Type::DeviceRGB:
-        return Color::NamedColor::Black;
-    case Type::DeviceCMYK:
-        return Color::from_cmyk(1.0f, 1.0f, 1.0f, 0.0f);
-    default:
-        TODO();
-    }
-}
-
-Color ColorSpace::color_from_parameters(ColorSpace::Type color_space, const Vector<Value>& args)
-{
-    switch (color_space) {
-    case Type::DeviceGray: {
-        VERIFY(args.size() == 1);
-        auto gray = static_cast<u8>(args[0].to_float() * 255.0f);
-        return Color(gray, gray, gray);
-    }
-    case Type::DeviceRGB: {
-        VERIFY(args.size() == 3);
-        auto r = static_cast<u8>(args[0].to_float() * 255.0f);
-        auto g = static_cast<u8>(args[1].to_float() * 255.0f);
-        auto b = static_cast<u8>(args[2].to_float() * 255.0f);
-        return Color(r, g, b);
-    }
-    case Type::DeviceCMYK: {
-        VERIFY(args.size() == 4);
-        auto c = args[0].to_float();
-        auto m = args[1].to_float();
-        auto y = args[2].to_float();
-        auto k = args[3].to_float();
-        return Color::from_cmyk(c, m, y, k);
-    }
-    default:
-        TODO();
-    }
-}
-
 void Renderer::render(Document& document, const Page& page, RefPtr<Gfx::Bitmap> bitmap)
 {
     Renderer(document, page, bitmap).render();
@@ -438,63 +384,63 @@ RENDERER_TODO(type3_font_set_glyph_width_and_bbox);
 RENDERER_HANDLER(set_stroking_space)
 {
     state().stroke_color_space = get_color_space(args[0]);
-    state().stroke_color = ColorSpace::default_color_for_color_space(state().stroke_color_space);
+    VERIFY(state().stroke_color_space);
 }
 
 RENDERER_HANDLER(set_painting_space)
 {
     state().paint_color_space = get_color_space(args[0]);
-    state().paint_color = ColorSpace::default_color_for_color_space(state().paint_color_space);
+    VERIFY(state().paint_color_space);
 }
 
 RENDERER_HANDLER(set_stroking_color)
 {
-    state().stroke_color = ColorSpace::color_from_parameters(state().stroke_color_space, args);
+    state().stroke_color = state().stroke_color_space->color(args);
 }
 
 RENDERER_TODO(set_stroking_color_extended);
 
 RENDERER_HANDLER(set_painting_color)
 {
-    state().paint_color = ColorSpace::color_from_parameters(state().paint_color_space, args);
+    state().paint_color = state().paint_color_space->color(args);
 }
 
 RENDERER_TODO(set_painting_color_extended);
 
 RENDERER_HANDLER(set_stroking_color_and_space_to_gray)
 {
-    state().stroke_color_space = ColorSpace::Type::DeviceGray;
-    state().stroke_color = ColorSpace::color_from_parameters(ColorSpace::Type::DeviceGray, args);
+    state().stroke_color_space = DeviceGrayColorSpace::the();
+    state().stroke_color = state().stroke_color_space->color(args);
 }
 
 RENDERER_HANDLER(set_painting_color_and_space_to_gray)
 {
-    state().paint_color_space = ColorSpace::Type::DeviceGray;
-    state().paint_color = ColorSpace::color_from_parameters(ColorSpace::Type::DeviceGray, args);
+    state().paint_color_space = DeviceGrayColorSpace::the();
+    state().paint_color = state().paint_color_space->color(args);
 }
 
 RENDERER_HANDLER(set_stroking_color_and_space_to_rgb)
 {
-    state().stroke_color_space = ColorSpace::Type::DeviceRGB;
-    state().stroke_color = ColorSpace::color_from_parameters(ColorSpace::Type::DeviceRGB, args);
+    state().stroke_color_space = DeviceRGBColorSpace::the();
+    state().stroke_color = state().stroke_color_space->color(args);
 }
 
 RENDERER_HANDLER(set_painting_color_and_space_to_rgb)
 {
-    state().paint_color_space = ColorSpace::Type::DeviceRGB;
-    state().paint_color = ColorSpace::color_from_parameters(ColorSpace::Type::DeviceRGB, args);
+    state().paint_color_space = DeviceRGBColorSpace::the();
+    state().paint_color = state().paint_color_space->color(args);
 }
 
 RENDERER_HANDLER(set_stroking_color_and_space_to_cmyk)
 {
-    state().stroke_color_space = ColorSpace::Type::DeviceCMYK;
-    state().stroke_color = ColorSpace::color_from_parameters(ColorSpace::Type::DeviceCMYK, args);
+    state().stroke_color_space = DeviceCMYKColorSpace::the();
+    state().stroke_color = state().stroke_color_space->color(args);
 }
 
 RENDERER_HANDLER(set_painting_color_and_space_to_cmyk)
 {
-    state().paint_color_space = ColorSpace::Type::DeviceCMYK;
-    state().paint_color = ColorSpace::color_from_parameters(ColorSpace::Type::DeviceCMYK, args);
+    state().paint_color_space = DeviceCMYKColorSpace::the();
+    state().paint_color = state().paint_color_space->color(args);
 }
 
 RENDERER_TODO(shade);
@@ -560,16 +506,19 @@ void Renderer::show_text(const String& string, int shift)
     }
 }
 
-ColorSpace::Type Renderer::get_color_space(const Value& value)
+RefPtr<ColorSpace> Renderer::get_color_space(const Value& value)
 {
     auto name = object_cast<NameObject>(value.as_object())->name();
-    auto color_space_opt = ColorSpace::color_space_from_string(name);
-    if (!color_space_opt.has_value()) {
-        // The name is probably a key into the resource dictionary
-        TODO();
-    }
 
-    return color_space_opt.value();
+    // Simple color spaces with no parameters, which can be specified directly
+    if (name == CommonNames::DeviceGray)
+        return DeviceGrayColorSpace::the();
+    if (name == CommonNames::DeviceRGB)
+        return DeviceRGBColorSpace::the();
+    if (name == CommonNames::DeviceCMYK)
+        return DeviceCMYKColorSpace::the();
+
+    TODO();
 }
 
 const Gfx::AffineTransform& Renderer::calculate_text_rendering_matrix()
diff --git a/Userland/Libraries/LibPDF/Renderer.h b/Userland/Libraries/LibPDF/Renderer.h
index 5709d1c564..36bd103d7a 100644
--- a/Userland/Libraries/LibPDF/Renderer.h
+++ b/Userland/Libraries/LibPDF/Renderer.h
@@ -16,22 +16,10 @@
 #include <LibGfx/Point.h>
 #include <LibGfx/Rect.h>
 #include <LibGfx/Size.h>
+#include <LibPDF/ColorSpace.h>
 #include <LibPDF/Document.h>
 #include <LibPDF/Object.h>
 
-#define ENUMERATE_COLOR_SPACES(V) \
-    V(DeviceGray)                 \
-    V(DeviceRGB)                  \
-    V(DeviceCMYK)                 \
-    V(CalGray)                    \
-    V(CalRGB)                     \
-    V(Lab)                        \
-    V(ICCBased)                   \
-    V(Indexed)                    \
-    V(Pattern)                    \
-    V(Separation)                 \
-    V(DeviceN)
-
 namespace PDF {
 
 enum class LineCapStyle : u8 {
@@ -73,23 +61,10 @@ struct TextState {
     bool knockout { true };
 };
 
-class ColorSpace {
-public:
-    enum class Type {
-#define ENUM(name) name,
-        ENUMERATE_COLOR_SPACES(ENUM)
-#undef ENUM
-    };
-
-    static Optional<ColorSpace::Type> color_space_from_string(const FlyString&);
-    static Color default_color_for_color_space(ColorSpace::Type);
-    static Color color_from_parameters(ColorSpace::Type color_space, const Vector<Value>& args);
-};
-
 struct GraphicsState {
     Gfx::AffineTransform ctm;
-    ColorSpace::Type stroke_color_space { ColorSpace::Type::DeviceGray };
-    ColorSpace::Type paint_color_space { ColorSpace::Type::DeviceGray };
+    RefPtr<ColorSpace> stroke_color_space { DeviceGrayColorSpace::the() };
+    RefPtr<ColorSpace> paint_color_space { DeviceGrayColorSpace::the() };
     Gfx::Color stroke_color { Gfx::Color::NamedColor::Black };
     Gfx::Color paint_color { Gfx::Color::NamedColor::Black };
     float line_width { 1.0f };
@@ -119,7 +94,7 @@ private:
 
     // shift is the manual advance given in the TJ command array
     void show_text(const String&, int shift = 0);
-    ColorSpace::Type get_color_space(const Value&);
+    RefPtr<ColorSpace> get_color_space(const Value&);
 
     ALWAYS_INLINE const GraphicsState& state() const { return m_graphics_state_stack.last(); }
     ALWAYS_INLINE GraphicsState& state() { return m_graphics_state_stack.last(); }