// © 2016 and later: Unicode, Inc. and others.

// License & terms of use: http://www.unicode.org/copyright.html

/*

**********************************************************************

*   Copyright (C) 1999-2016, International Business Machines

*   Corporation and others.  All Rights Reserved.

**********************************************************************

*   Date        Name        Description

*   10/22/99    alan        Creation.  This is an internal header.

*                           It should not be exported.

**********************************************************************

*/

#ifndef UVECTOR_H

#define UVECTOR_H

#include "unicode/utypes.h"

#include "unicode/uobject.h"

#include "cmemory.h"

#include "uarrsort.h"

#include "uelement.h"

U_NAMESPACE_BEGIN

/**

 * <p>Ultralightweight C++ implementation of a <tt>void*</tt> vector

 * that is (mostly) compatible with java.util.Vector.

 *

 * <p>This is a very simple implementation, written to satisfy an

 * immediate porting need.  As such, it is not completely fleshed out,

 * and it aims for simplicity and conformity.  Nonetheless, it serves

 * its purpose (porting code from java that uses java.util.Vector)

 * well, and it could be easily made into a more robust vector class.

 *

 * <p><b>Design notes</b>

 *

 * <p>There is index bounds checking, but little is done about it.  If

 * indices are out of bounds, either nothing happens, or zero is

 * returned.  We <em>do</em> avoid indexing off into the weeds.

 *

 * <p>There is detection of out of memory, but the handling is very

 * coarse-grained -- similar to UnicodeString's protocol, but even

 * coarser.  The class contains <em>one static flag</em> that is set

 * when any call to <tt>new</tt> returns zero.  This allows the caller

 * to use several vectors and make just one check at the end to see if

 * a memory failure occurred.  This is more efficient than making a

 * check after each call on each vector when doing many operations on

 * multiple vectors.  The single static flag works best when memory

 * failures are infrequent, and when recovery options are limited or

 * nonexistent.

 *

 * <p>Since we don't have garbage collection, UVector was given the

 * option to <em>own</em>its contents.  To employ this, set a deleter

 * function.  The deleter is called on a void* pointer when that

 * pointer is released by the vector, either when the vector itself is

 * destructed, or when a call to setElementAt() overwrites an element,

 * or when a call to remove() or one of its variants explicitly

 * removes an element.  If no deleter is set, or the deleter is set to

 * zero, then it is assumed that the caller will delete elements as

 * needed.

 *

 * <p>In order to implement methods such as contains() and indexOf(),

 * UVector needs a way to compare objects for equality.  To do so, it

 * uses a comparison function, or "comparer."  If the comparer is not

 * set, or is set to zero, then all such methods will act as if the

 * vector contains no element.  That is, indexOf() will always return

 * -1, contains() will always return false, etc.

 *

 * <p><b>To do</b>

 *

 * <p>Improve the handling of index out of bounds errors.

 *

 * @author Alan Liu

 */

class U_COMMON_API UVector : public UObject {

    // NOTE: UVector uses the UHashKey (union of void* and int32_t) as

    // its basic storage type.  It uses UElementsAreEqual as its

    // comparison function.  It uses UObjectDeleter as its deleter

    // function.  These are named for hashtables, but used here as-is

    // rather than duplicating the type.  This allows sharing of

    // support functions.

private:

    int32_t count;

    int32_t capacity;

    UElement* elements;

    UObjectDeleter *deleter;

    UElementsAreEqual *comparer;

public:

    UVector(UErrorCode &status);

    UVector(int32_t initialCapacity, UErrorCode &status);

    UVector(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status);

    UVector(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status);

    virtual ~UVector();

    /**

     * Assign this object to another (make this a copy of 'other').

     * Use the 'assign' function to assign each element.

     */

    void assign(const UVector& other, UElementAssigner *assign, UErrorCode &ec);

    /**

     * Compare this vector with another.  They will be considered

     * equal if they are of the same size and all elements are equal,

     * as compared using this object's comparer.

     */

    bool operator==(const UVector& other);

    /**

     * Equivalent to !operator==()

     */

    inline bool operator!=(const UVector& other);

    //------------------------------------------------------------

    // java.util.Vector API

    //------------------------------------------------------------

    /*

     * Old version of addElement, with non-standard error handling.

     * Will be removed once all uses have been switched to the new addElement().

     */

    void addElementX(void* obj, UErrorCode &status);

    void addElement(int32_t elem, UErrorCode &status);

    void setElementAt(void* obj, int32_t index);

    void setElementAt(int32_t elem, int32_t index);

    void insertElementAt(void* obj, int32_t index, UErrorCode &status);

    void insertElementAt(int32_t elem, int32_t index, UErrorCode &status);

    void* elementAt(int32_t index) const;

    int32_t elementAti(int32_t index) const;

    UBool equals(const UVector &other) const;

    inline void* firstElement(void) const;

    inline void* lastElement(void) const;

    inline int32_t lastElementi(void) const;

    int32_t indexOf(void* obj, int32_t startIndex = 0) const;

    int32_t indexOf(int32_t obj, int32_t startIndex = 0) const;

    inline UBool contains(void* obj) const;

    inline UBool contains(int32_t obj) const;

    UBool containsAll(const UVector& other) const;

    UBool removeAll(const UVector& other);

    UBool retainAll(const UVector& other);

    void removeElementAt(int32_t index);

    UBool removeElement(void* obj);

    void removeAllElements();

    inline int32_t size(void) const;

    inline UBool isEmpty(void) const;

    /*

     * Old version of ensureCapacity, with non-standard error handling.

     * Will be removed once all uses have been switched to the new ensureCapacity().

     */

    UBool ensureCapacityX(int32_t minimumCapacity, UErrorCode &status);

    /**

     * Change the size of this vector as follows: If newSize is

     * smaller, then truncate the array, possibly deleting held

     * elements for i >= newSize.  If newSize is larger, grow the

     * array, filling in new slots with NULL.

     */

    void setSize(int32_t newSize, UErrorCode &status);

    /**

     * Fill in the given array with all elements of this vector.

     */

    void** toArray(void** result) const;

    //------------------------------------------------------------

    // New API

    //------------------------------------------------------------

    UObjectDeleter *setDeleter(UObjectDeleter *d);

    UElementsAreEqual *setComparer(UElementsAreEqual *c);

    inline void* operator[](int32_t index) const;

    /**

     * Removes the element at the given index from this vector and

     * transfer ownership of it to the caller.  After this call, the

     * caller owns the result and must delete it and the vector entry

     * at 'index' is removed, shifting all subsequent entries back by

     * one index and shortening the size of the vector by one.  If the

     * index is out of range or if there is no item at the given index

     * then 0 is returned and the vector is unchanged.

     */

    void* orphanElementAt(int32_t index);

    /**

     * Returns true if this vector contains none of the elements

     * of the given vector.

     * @param other vector to be checked for containment

     * @return true if the test condition is met

     */

    UBool containsNone(const UVector& other) const;

    /**

     * Insert the given object into this vector at its sorted position

     * as defined by 'compare'.  The current elements are assumed to

     * be sorted already.

     */

    void sortedInsert(void* obj, UElementComparator *compare, UErrorCode& ec);

    /**

     * Insert the given integer into this vector at its sorted position

     * as defined by 'compare'.  The current elements are assumed to

     * be sorted already.

     */

    void sortedInsert(int32_t obj, UElementComparator *compare, UErrorCode& ec);

    /**

     * Sort the contents of the vector, assuming that the contents of the

     * vector are of type int32_t.

     */

    void sorti(UErrorCode &ec);

    /**

      * Sort the contents of this vector, using a caller-supplied function

      * to do the comparisons.  (It's confusing that

      *  UVector's UElementComparator function is different from the

      *  UComparator function type defined in uarrsort.h)

      */

    void sort(UElementComparator *compare, UErrorCode &ec);

    /**

     * Stable sort the contents of this vector using a caller-supplied function

     * of type UComparator to do the comparison.  Provides more flexibility

     * than UVector::sort() because an additional user parameter can be passed to

     * the comparison function.

     */

    void sortWithUComparator(UComparator *compare, const void *context, UErrorCode &ec);

    /**

     * ICU "poor man's RTTI", returns a UClassID for this class.

     */

    static UClassID U_EXPORT2 getStaticClassID();

    /**

     * ICU "poor man's RTTI", returns a UClassID for the actual class.

     */

    virtual UClassID getDynamicClassID() const;

private:

    void _init(int32_t initialCapacity, UErrorCode &status);

    int32_t indexOf(UElement key, int32_t startIndex = 0, int8_t hint = 0) const;

    void sortedInsert(UElement e, UElementComparator *compare, UErrorCode& ec);

    // Disallow

    UVector(const UVector&);

    // Disallow

    UVector& operator=(const UVector&);

};

/**

 * <p>Ultralightweight C++ implementation of a <tt>void*</tt> stack

 * that is (mostly) compatible with java.util.Stack.  As in java, this

 * is merely a paper thin layer around UVector.  See the UVector

 * documentation for further information.

 *

 * <p><b>Design notes</b>

 *

 * <p>The element at index <tt>n-1</tt> is (of course) the top of the

 * stack.

 *

 * <p>The poorly named <tt>empty()</tt> method doesn't empty the

 * stack; it determines if the stack is empty.

 *

 * @author Alan Liu

 */

class U_COMMON_API UStack : public UVector {

public:

    UStack(UErrorCode &status);

    UStack(int32_t initialCapacity, UErrorCode &status);

    UStack(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status);

    UStack(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status);

    virtual ~UStack();

    // It's okay not to have a virtual destructor (in UVector)

    // because UStack has no special cleanup to do.

    inline UBool empty(void) const;

    inline void* peek(void) const;

    inline int32_t peeki(void) const;

    void* pop(void);

    int32_t popi(void);

    inline void* push(void* obj, UErrorCode &status);

    inline int32_t push(int32_t i, UErrorCode &status);

    /*

    If the object o occurs as an item in this stack,

    this method returns the 1-based distance from the top of the stack.

    */

    int32_t search(void* obj) const;

    /**

     * ICU "poor man's RTTI", returns a UClassID for this class.

     */

    static UClassID U_EXPORT2 getStaticClassID();

    /**

     * ICU "poor man's RTTI", returns a UClassID for the actual class.

     */

    virtual UClassID getDynamicClassID() const;

private:

    // Disallow

    UStack(const UStack&);

    // Disallow

    UStack& operator=(const UStack&);

};

// UVector inlines

inline int32_t UVector::size(void) const {

    return count;

}

inline UBool UVector::isEmpty(void) const {

    return count == 0;

}

inline UBool UVector::contains(void* obj) const {

    return indexOf(obj) >= 0;

}

inline UBool UVector::contains(int32_t obj) const {

    return indexOf(obj) >= 0;

}

inline void* UVector::firstElement(void) const {

    return elementAt(0);

}

inline void* UVector::lastElement(void) const {

    return elementAt(count-1);

}

inline int32_t UVector::lastElementi(void) const {

    return elementAti(count-1);

}

inline void* UVector::operator[](int32_t index) const {

    return elementAt(index);

}

inline bool UVector::operator!=(const UVector& other) {

    return !operator==(other);

}

// UStack inlines

inline UBool UStack::empty(void) const {

    return isEmpty();

}

inline void* UStack::peek(void) const {

    return lastElement();

}

inline int32_t UStack::peeki(void) const {

    return lastElementi();

}

inline void* UStack::push(void* obj, UErrorCode &status) {

    addElementX(obj, status);

    return obj;

}

inline int32_t UStack::push(int32_t i, UErrorCode &status) {

    addElement(i, status);

    return i;

}

U_NAMESPACE_END

#endif