pdf/engine/tests/display_list_test.cpp

#include <gtest/gtest.h>
#include <pdfengine/display_list.hpp>
#include <string>
#include <vector>

using namespace pdfengine;

class MockVisitor : public CommandVisitor {
public:
    std::vector<std::string> calls;

    void visit(const SaveStateCommand&) override { calls.push_back("SaveState"); }
    void visit(const RestoreStateCommand&) override { calls.push_back("RestoreState"); }
    void visit(const SetTransformCommand& cmd) override { calls.push_back("SetTransform(" + std::to_string(cmd.matrix.a) + ")"); }
    void visit(const FillRectCommand& cmd) override { calls.push_back("FillRect(" + std::to_string(cmd.width) + ")"); }
    void visit(const DrawTextCommand& cmd) override { calls.push_back("DrawText(" + cmd.text + ")"); }
    void visit(const FillPathCommand&) override { calls.push_back("FillPath"); }
    void visit(const StrokePathCommand&) override { calls.push_back("StrokePath"); }
    void visit(const FillStrokePathCommand&) override { calls.push_back("FillStrokePath"); }
    void visit(const DrawImageCommand&) override { calls.push_back("DrawImage"); }
};

TEST(DisplayListTest, RecordAndReplay) {
    DisplayList list;
    
    EXPECT_EQ(list.size(), 0);
    
    list.saveState();
    list.setTransform(Matrix(2.0f, 0.0f, 0.0f, 2.0f, 0.0f, 0.0f));
    list.fillRect(10.0f, 10.0f, 100.0f, 50.0f);
    list.drawText("Hello World", 20.0f, 30.0f);
    list.restoreState();

    EXPECT_EQ(list.size(), 5);

    MockVisitor visitor;
    list.replay(visitor);

    ASSERT_EQ(visitor.calls.size(), 5);
    EXPECT_EQ(visitor.calls[0], "SaveState");
    EXPECT_EQ(visitor.calls[1], "SetTransform(2.000000)");
    EXPECT_EQ(visitor.calls[2], "FillRect(100.000000)");
    EXPECT_EQ(visitor.calls[3], "DrawText(Hello World)");
    EXPECT_EQ(visitor.calls[4], "RestoreState");
}

TEST(DisplayListTest, Clear) {
    DisplayList list;
    list.saveState();
    list.fillRect(0, 0, 10, 10);
    EXPECT_EQ(list.size(), 2);
    
    list.clear();
    EXPECT_EQ(list.size(), 0);
}