cocos_lib/cocos/core/memop/CachedArray.h

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 Copyright (c) 2021-2023 Xiamen Yaji Software Co., Ltd.

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#pragma once

#include <string.h>
#include <climits>
#include "base/Object.h"
#include "base/TypeDef.h"
#include "base/memory/Memory.h"

namespace cc {

template <typename T>
class CachedArray final {
public:
    explicit CachedArray(uint size = 1U) {
        _size = 0;
        _capacity = std::max(size, 1U);
        _array = ccnew T[_capacity];
    }

    // The rule of five applies here
    ~CachedArray() {
        CC_SAFE_DELETE_ARRAY(_array);
    }

    CachedArray(const CachedArray &other)
    : _size(other._size), _capacity(other._capacity), _array(ccnew T[other._capacity]) {
        memcpy(_array, other._array, _size * sizeof(T));
    }

    CachedArray &operator=(const CachedArray &other) {
        if (this != &other) {
            delete[] _array;
            _size = other._size;
            _capacity = other._capacity;
            _array = ccnew T[_capacity];
            memcpy(_array, other._array, _size * sizeof(T));
        }
        return *this;
    }

    CachedArray(CachedArray &&other) noexcept : _size(other._size), _capacity(other._capacity), _array(other._array) {
        other._size = 0;
        other._capacity = 0;
        other._array = nullptr;
    }

    CachedArray &operator=(CachedArray &&other) noexcept {
        if (this != &other) {
            delete[] _array;
            _size = other._size;
            _capacity = other._capacity;
            _array = other._array;
            other._size = 0;
            other._capacity = 0;
            other._array = nullptr;
        }
        return *this;
    }

    // Subscription operators
    T &operator[](uint index) {
        return _array[index];
    }

    const T &operator[](uint index) const {
        return _array[index];
    }

    inline void clear() { _size = 0; }
    inline uint size() const { return _size; }
    inline T pop() { return _array[--_size]; }

    void reserve(uint size) {
        if (size > _capacity) {
            T *temp = _array;
            _array = ccnew T[size];
            memcpy(_array, temp, _capacity * sizeof(T));
            _capacity = size;
            delete[] temp;
        }
    }

    void push(T item) {
        if (_size >= _capacity) {
            T *temp = _array;
            _array = ccnew T[_capacity * 2];
            memcpy(_array, temp, _capacity * sizeof(T));
            _capacity *= 2;
            delete[] temp;
        }
        _array[_size++] = item;
    }

    void concat(const CachedArray<T> &array) {
        if (_size + array._size > _capacity) {
            T *temp = _array;
            uint size = std::max(_capacity * 2, _size + array._size);
            _array = ccnew T[size];
            memcpy(_array, temp, _size * sizeof(T));
            _capacity = size;
            delete[] temp;
        }
        memcpy(_array + _size, array._array, array._size * sizeof(T));
        _size += array._size;
    }

    void concat(T *array, uint count) {
        if (_size + count > _capacity) {
            T *temp = _array;
            uint size = std::max(_capacity * 2, _size + count);
            _array = ccnew T[size];
            memcpy(_array, temp, _size * sizeof(T));
            _capacity = size;
            delete[] temp;
        }
        memcpy(_array + _size, array, count * sizeof(T));
        _size += count;
    }

    void fastRemove(uint idx) {
        if (idx >= _size) {
            return;
        }
        _array[idx] = _array[--_size];
    }

    uint indexOf(T item) {
        for (uint i = 0; i < _size; ++i) {
            if (_array[i] == item) {
                return i;
            }
        }
        return UINT_MAX;
    }

private:
    uint _size = 0;
    uint _capacity = 0;
    T *_array = nullptr;
};

} // namespace cc