include/rive/core/binary_reader.hpp

#ifndef _RIVE_CORE_BINARY_READER_HPP_
#define _RIVE_CORE_BINARY_READER_HPP_

#include <string>
#include <vector>
#include "rive/span.hpp"
#include "rive/core/type_conversions.hpp"

namespace rive {
    class BinaryReader {
    private:
        Span<const uint8_t> m_Bytes;
        const uint8_t* m_Position;
        bool m_Overflowed;
        bool m_IntRangeError;

        void overflow();
        void intRangeError();

    public:
        explicit BinaryReader(Span<const uint8_t>);
        bool didOverflow() const;
        bool didIntRangeError() const;
        bool hasError() const { return m_Overflowed || m_IntRangeError; }
        bool reachedEnd() const;

        size_t lengthInBytes() const;

        std::string readString();
        Span<const uint8_t> readBytes();
        float readFloat32();
        uint8_t readByte();
        uint32_t readUint32();
        uint64_t readVarUint64(); // Reads a LEB128 encoded uint64_t
        
        // This will cast the uint read to the requested size, but if the
        // raw value was out-of-range, instead returns 0 and sets the IntRangeError.
        template <typename T> T readVarUintAs() {
            auto value = this->readVarUint64();
            if (!fitsIn<T>(value)) {
                value = 0;
                this->intRangeError();
            }
            return static_cast<T>(value);
        }
    };
} // namespace rive

#endif