include/bej_decoder_core.h

#pragma once

#include "rde_common.h"

#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C"
{
#endif

    /**
     * @brief Indicates whether a new BEJ section falls inside a BEJ array or a
     * BEJ set or none of those.
     */
    enum BejSectionType
    {
        bejSectionNoType,
        bejSectionSet,
        bejSectionArray,
    };

    /**
     * @brief These stack entries are needed to implement the decoding
     * non-recursively.
     */
    struct BejStackProperty
    {
        // Indicates whether we are inside an array or a set or an annotation.
        enum BejSectionType sectionType;
        // Indicate whether we have property names for properties.
        bool addPropertyName;
        // Offset to the parent property in schema dictionary.
        uint16_t mainDictPropOffset;
        // Offset to the parent property in annotation dictionary.
        uint16_t annoDictPropOffset;
        // Offset to the end of the array or set or annotation.
        uint32_t streamEndOffset;
    };

    struct BejDictionaries
    {
        const uint8_t* schemaDictionary;
        const uint8_t* annotationDictionary;
        const uint8_t* errorDictionary;
    };

    /**
     * @brief Holds the information related to the current bejTuple being
     * decoded.
     */
    struct BejDecoderStates
    {
        bool addPropertyName;
        uint16_t mainDictPropOffset;
        uint16_t annoDictPropOffset;
        uint32_t encodedStreamOffset;
        const uint8_t* encodedSubStream;
    };

    /**
     * @brief Callbacks for decoded data.
     *
     * dataPtr in the callback functions can be used for extra arguments.
     */
    struct BejDecodedCallback
    {
        /**
         * @brief Calls when a Set is detected.
         */
        int (*callbackSetStart)(const char* propertyName, void* dataPtr);

        /**
         * @brief Calls when an end of a Set is found.
         */
        int (*callbackSetEnd)(void* dataPtr);

        /**
         * @brief Calls when an array is detected.
         */
        int (*callbackArrayStart)(const char* propertyName, void* dataPtr);

        /**
         * @brief Calls when an end of an array is found.
         */
        int (*callbackArrayEnd)(void* dataPtr);

        /**
         * @brief Calls after a property is finished unless this is the last
         * property in a Set or an array. In that case appropriate
         * callbackSetEnd or callbackArrayEnd will be called.
         */
        int (*callbackPropertyEnd)(void* dataPtr);

        /**
         * @brief Calls when a Null property is found or the property length is
         * 0.
         */
        int (*callbackNull)(const char* propertyName, void* dataPtr);

        /**
         * @brief Calls when an Integer property is found.
         */
        int (*callbackInteger)(const char* propertyName, int64_t value,
                               void* dataPtr);

        /**
         * @brief Calls when an Enum property is found.
         */
        int (*callbackEnum)(const char* propertyName, const char* value,
                            void* dataPtr);

        /**
         * @brief Calls when a String property is found.
         */
        int (*callbackString)(const char* propertyName, const char* value,
                              void* dataPtr);

        /**
         * @brief Calls when a Real value property is found.
         */
        int (*callbackReal)(const char* propertyName,
                            const struct BejReal* value, void* dataPtr);

        /**
         * @brief Calls when a Bool property is found.
         */
        int (*callbackBool)(const char* propertyName, bool value,
                            void* dataPtr);

        /**
         * @brief Calls when an Annotated property is found.
         */
        int (*callbackAnnotation)(const char* propertyName, void* dataPtr);

        /**
         * @brief Calls when a read only property is found.
         */
        int (*callbackReadonlyProperty)(uint32_t sequenceNumber, void* dataPtr);
    };

    /**
     * @brief Stack for holding BejStackProperty types. Decoder core is not
     * responsible for creating or deleting stack memory. User of the decoder
     * core is responsible for creating and deleting stack memory.
     *
     * dataPtr in the callback functions can be used for extra arguments.
     */
    struct BejStackCallback
    {
        /**
         * @brief Return true if the stack is empty.
         */
        bool (*stackEmpty)(void* dataPtr);

        /**
         * @brief View the object at the top of the stack. If the stack is
         * empty, this will return NULL.
         */
        const struct BejStackProperty* (*stackPeek)(void* dataPtr);

        /**
         * @brief Removes the top most object from the stack. Client of the
         * decoder core is responsible for destroying the memory for the removed
         * object.
         */
        void (*stackPop)(void* dataPtr);

        /**
         * @brief Push an object into the stack. Returns 0 if the operation is
         * successfull. Client of the decoder core is responsible for allocating
         * memory for the new object.
         */
        int (*stackPush)(const struct BejStackProperty* const property,
                         void* dataPtr);
    };

    /**
     * @brief Used to pass parameters to BEJ decoding local functions.
     */
    struct BejHandleTypeFuncParam
    {
        struct BejDecoderStates state;
        struct BejSFLV sflv;
        const uint8_t* mainDictionary;
        const uint8_t* annotDictionary;
        const struct BejDecodedCallback* decodedCallback;
        const struct BejStackCallback* stackCallback;
        void* callbacksDataPtr;
        void* stackDataPtr;
    };

    /**
     * @brief Decodes a PLDM block. Maximum encoded stream size the decoder
     * supports is 32bits.
     *
     * @param[in] dictionaries - dictionaries needed for decoding.
     * @param[in] encodedPldmBlock - encoded PLDM block.
     * @param[in] blockLength - length of the PLDM block.
     * @param[in] stackCallback - callbacks for stack handlers. callbacks in
     * stackCallback struct should be set to valid functions.
     * @param[in] decodedCallback - callbacks for extracting decoded
     * properties. callbacks in decodedCallback struct should be set to
     * NULL or valid functions.
     * @param[in] callbacksDataPtr - data pointer to pass to decoded callbacks.
     * This can be used pass additional data.
     * @param[in] stackDataPtr - data pointer to pass to stack callbacks. This
     * can be used pass additional data.
     *
     * @return 0 if successful.
     */
    int bejDecodePldmBlock(const struct BejDictionaries* dictionaries,
                           const uint8_t* encodedPldmBlock,
                           uint32_t blockLength,
                           const struct BejStackCallback* stackCallback,
                           const struct BejDecodedCallback* decodedCallback,
                           void* callbacksDataPtr, void* stackDataPtr);

#ifdef __cplusplus
}
#endif