release_embedded.cpp

#include <QApplication>
#include <QWidget>
#include <algorithm>
#include <cstddef>
#include <cstdint>
#include <iostream>
#include <stdexcept>
#include <utility>
#include <vector>

#include "frame_player_widget.hpp"
#include "generated/embedded_video_cache.hpp"

namespace {
    using Rectangle = VIDEO::FramePlayerWidget::Rectangle;
    using Frame = VIDEO::FramePlayerWidget::Frame;

    std::int32_t readInt32LE(const unsigned char *data, std::size_t size, std::size_t &offset) {
        if (offset + 4 > size) {
            throw std::runtime_error("unexpected end of embedded cache data");
        }

        const std::uint32_t value =
            static_cast<std::uint32_t>(data[offset]) |
            (static_cast<std::uint32_t>(data[offset + 1]) << 8) |
            (static_cast<std::uint32_t>(data[offset + 2]) << 16) |
            (static_cast<std::uint32_t>(data[offset + 3]) << 24);

        offset += 4;
        return static_cast<std::int32_t>(value);
    }

    std::vector<Frame> parseFrames() {
        std::vector<Frame> frames;
        std::size_t offset = 0;

        while (offset < BAD_APPLE_EMBEDDED::kVideoCacheSize) {
            const int rectangleCount = readInt32LE(
                BAD_APPLE_EMBEDDED::kVideoCache,
                BAD_APPLE_EMBEDDED::kVideoCacheSize,
                offset
            );

            if (rectangleCount < 0) {
                throw std::runtime_error("embedded cache contains a negative rectangle count");
            }

            Frame frame;
            frame.reserve(static_cast<std::size_t>(rectangleCount));

            for (int i = 0; i < rectangleCount; ++i) {
                const int row = readInt32LE(BAD_APPLE_EMBEDDED::kVideoCache, BAD_APPLE_EMBEDDED::kVideoCacheSize, offset);
                const int col = readInt32LE(BAD_APPLE_EMBEDDED::kVideoCache, BAD_APPLE_EMBEDDED::kVideoCacheSize, offset);
                const int height = readInt32LE(BAD_APPLE_EMBEDDED::kVideoCache, BAD_APPLE_EMBEDDED::kVideoCacheSize, offset);
                const int width = readInt32LE(BAD_APPLE_EMBEDDED::kVideoCache, BAD_APPLE_EMBEDDED::kVideoCacheSize, offset);

                frame.push_back({{row, col}, {height, width}});
            }

            frames.push_back(std::move(frame));
        }

        return frames;
    }

    int frameDelayMs() {
        return std::max(1, static_cast<int>(1000.0 / std::max(BAD_APPLE_EMBEDDED::kVideoFps, 1.0)));
    }
}

int main(int argc, char *argv[]) {
#ifdef __linux__
    qputenv("QT_QPA_PLATFORM", "xcb");
#endif

    QApplication app(argc, argv);

    try {
        auto *player = new VIDEO::FramePlayerWidget(
            parseFrames(),
            QSize(BAD_APPLE_EMBEDDED::kVideoWidth, BAD_APPLE_EMBEDDED::kVideoHeight),
            frameDelayMs()
        );
        player->setAttribute(Qt::WA_DeleteOnClose);
        player->start();
    } catch (const std::exception &ex) {
        std::cerr << ex.what() << '\n';
        return 1;
    }

    return app.exec();
}