fsfw/container/ArrayList.h

#ifndef FSFW_CONTAINER_ARRAYLIST_H_
#define FSFW_CONTAINER_ARRAYLIST_H_

#include "../returnvalues/HasReturnvaluesIF.h"
#include "../serialize/SerializeAdapter.h"
#include "../serialize/SerializeIF.h"

/**
 * @brief     A List that stores its values in an array.
 * @details
 * The underlying storage is an array that can be allocated by the class
 * itself or supplied via ctor.
 *
 * @ingroup container
 */
template<typename T, typename count_t = uint8_t>
class ArrayList {
    template<typename U, typename count> friend class SerialArrayListAdapter;
public:
    static const uint8_t INTERFACE_ID = CLASS_ID::ARRAY_LIST;
    static const ReturnValue_t FULL = MAKE_RETURN_CODE(0x01);

    /**
     * This is the allocating constructor.
     * It allocates an array of the specified size.
     * @param maxSize
     */
    ArrayList(count_t maxSize) :
        size(0), maxSize_(maxSize), allocated(true) {
        entries = new T[maxSize];
    }

    /**
     * This is the non-allocating constructor
     *
     * It expects a pointer to an array of a certain size and initializes
     * itself to it.
     *
     * @param storage the array to use as backend
     * @param maxSize size of storage
     * @param size size of data already present in storage
     */
    ArrayList(T *storage, count_t maxSize, count_t size = 0) :
        size(size), entries(storage), maxSize_(maxSize), allocated(false) {
    }

    /**
     * Copying is forbiden by declaring copy ctor and copy assignment deleted
     * It is too ambigous in this case.
     * (Allocate a new backend? Use the same? What to do in an modifying call?)
     */
    ArrayList(const ArrayList& other) = delete;
    const ArrayList& operator=(const ArrayList& other) = delete;

    /**
     * Number of Elements stored in this List
     */
    count_t size;


    /**
     * Destructor, if the allocating constructor was used, it deletes the array.
     */
    virtual ~ArrayList() {
        if (allocated) {
            delete[] entries;
        }
    }

    /**
     * An Iterator to go trough an ArrayList
     *
     * It stores a pointer to an element and increments the
     * pointer when incremented itself.
     */
    class Iterator {
    public:
        /**
         * Empty ctor, points to NULL
         */
        Iterator(): value(0) {}

        /**
         * Initializes the Iterator to point to an element
         *
         * @param initialize
         */
        Iterator(T *initialize) {
            value = initialize;
        }

        /**
         * The current element the iterator points to
         */
        T *value;

        Iterator& operator++() {
            value++;
            return *this;
        }

        Iterator operator++(int) {
            Iterator tmp(*this);
            operator++();
            return tmp;
        }

        Iterator& operator--() {
            value--;
            return *this;
        }

        Iterator operator--(int) {
            Iterator tmp(*this);
            operator--();
            return tmp;
        }

        T& operator*() {
            return *value;
        }

        const T& operator*() const {
            return *value;
        }

        T *operator->() {
            return value;
        }

        const T *operator->() const {
            return value;
        }
    };

    friend bool operator==(const ArrayList::Iterator& lhs,
            const ArrayList::Iterator& rhs) {
        return (lhs.value == rhs.value);
    }

    friend bool operator!=(const ArrayList::Iterator& lhs,
            const ArrayList::Iterator& rhs) {
        return not (lhs.value == rhs.value);
    }

    /**
     * Iterator pointing to the first stored elmement
     *
     * @return Iterator to the first element
     */
    Iterator begin() const {
        return Iterator(&entries[0]);
    }

    /**
     * returns an Iterator pointing to the element after the last stored entry
     *
     * @return Iterator to the element after the last entry
     */
    Iterator end() const {
        return Iterator(&entries[size]);
    }

    T & operator[](count_t i) const {
        return entries[i];
    }

    /**
     * The first element
     *
     * @return pointer to the first stored element
     */
    T *front() {
        return entries;
    }

    /**
     * The last element
     *
     * does not return a valid pointer if called on an empty list.
     *
     * @return pointer to the last stored element
     */
    T *back() {
        return &entries[size - 1];
        //Alternative solution
        //return const_cast<T*>(static_cast<const T*>(*this).back());
    }

    const T* back() const{
        return &entries[size-1];
    }

    /**
     * The maximum number of elements this List can contain
     *
     * @return maximum number of elements
     */
    size_t maxSize() const {
        return this->maxSize_;
    }

    /**
     * Insert a new element into the list.
     *
     * The new element is inserted after the last stored element.
     *
     * @param entry
     * @return
     *          -@c FULL if the List is full
     *          -@c RETURN_OK else
     */
    ReturnValue_t insert(T entry) {
        if (size >= maxSize_) {
            return FULL;
        }
        entries[size] = entry;
        ++size;
        return HasReturnvaluesIF::RETURN_OK;
    }

    /**
     * clear the List
     *
     * This does not actually clear all entries, it only sets the size to 0.
     */
    void clear() {
        size = 0;
    }

    count_t remaining() {
        return (maxSize_ - size);
    }

protected:
    /**
     * pointer to the array in which the entries are stored
     */
    T *entries;
    /**
     * remembering the maximum size
     */
    size_t maxSize_;

    /**
     * true if the array was allocated and needs to be deleted in the destructor.
     */
    bool allocated;
};



#endif /* FSFW_CONTAINER_ARRAYLIST_H_ */