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

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

/*

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

*

*   Copyright (C) 2007, International Business Machines

*   Corporation and others.  All Rights Reserved.

*

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

*   file name:  unisetspan.h

*   encoding:   UTF-8

*   tab size:   8 (not used)

*   indentation:4

*

*   created on: 2007mar01

*   created by: Markus W. Scherer

*/

#ifndef __UNISETSPAN_H__

#define __UNISETSPAN_H__

#include "unicode/utypes.h"

#include "unicode/uniset.h"

U_NAMESPACE_BEGIN

/*

 * Implement span() etc. for a set with strings.

 * Avoid recursion because of its exponential complexity.

 * Instead, try multiple paths at once and track them with an IndexList.

 */

class UnicodeSetStringSpan : public UMemory {

public:

    /*

     * Which span() variant will be used?

     * The object is either built for one variant and used once,

     * or built for all and may be used many times.

     */

    enum {

        FWD             = 0x20,

        BACK            = 0x10,

        UTF16           = 8,

        UTF8            = 4,

        CONTAINED       = 2,

        NOT_CONTAINED   = 1,

        ALL             = 0x3f,

        FWD_UTF16_CONTAINED     = FWD  | UTF16 |     CONTAINED,

        FWD_UTF16_NOT_CONTAINED = FWD  | UTF16 | NOT_CONTAINED,

        FWD_UTF8_CONTAINED      = FWD  | UTF8  |     CONTAINED,

        FWD_UTF8_NOT_CONTAINED  = FWD  | UTF8  | NOT_CONTAINED,

        BACK_UTF16_CONTAINED    = BACK | UTF16 |     CONTAINED,

        BACK_UTF16_NOT_CONTAINED= BACK | UTF16 | NOT_CONTAINED,

        BACK_UTF8_CONTAINED     = BACK | UTF8  |     CONTAINED,

        BACK_UTF8_NOT_CONTAINED = BACK | UTF8  | NOT_CONTAINED

    };

    UnicodeSetStringSpan(const UnicodeSet &set, const UVector &setStrings, uint32_t which);

    // Copy constructor. Assumes which==ALL for a frozen set.

    UnicodeSetStringSpan(const UnicodeSetStringSpan &otherStringSpan, const UVector &newParentSetStrings);

    ~UnicodeSetStringSpan();

    /*

     * Do the strings need to be checked in span() etc.?

     * @return true if strings need to be checked (call span() here),

     *         false if not (use a BMPSet for best performance).

     */

    inline UBool needsStringSpanUTF16();

    inline UBool needsStringSpanUTF8();

    // For fast UnicodeSet::contains(c).

    inline UBool contains(UChar32 c) const;

    int32_t span(const UChar *s, int32_t length, USetSpanCondition spanCondition) const;

    int32_t spanBack(const UChar *s, int32_t length, USetSpanCondition spanCondition) const;

    int32_t spanUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const;

    int32_t spanBackUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const;

private:

    // Special spanLength byte values.

    enum {

        // The spanLength is >=0xfe.

        LONG_SPAN=0xfe,

        // All code points in the string are contained in the parent set.

        ALL_CP_CONTAINED=0xff

    };

    // Add a starting or ending string character to the spanNotSet

    // so that a character span ends before any string.

    void addToSpanNotSet(UChar32 c);

    int32_t spanNot(const UChar *s, int32_t length) const;

    int32_t spanNotBack(const UChar *s, int32_t length) const;

    int32_t spanNotUTF8(const uint8_t *s, int32_t length) const;

    int32_t spanNotBackUTF8(const uint8_t *s, int32_t length) const;

    // Set for span(). Same as parent but without strings.

    UnicodeSet spanSet;

    // Set for span(not contained).

    // Same as spanSet, plus characters that start or end strings.

    UnicodeSet *pSpanNotSet;

    // The strings of the parent set.

    const UVector &strings;

    // Pointer to the UTF-8 string lengths.

    // Also pointer to further allocated storage for meta data and

    // UTF-8 string contents as necessary.

    int32_t *utf8Lengths;

    // Pointer to the part of the (utf8Lengths) memory block that stores

    // the lengths of span(), spanBack() etc. for each string.

    uint8_t *spanLengths;

    // Pointer to the part of the (utf8Lengths) memory block that stores

    // the UTF-8 versions of the parent set's strings.

    uint8_t *utf8;

    // Number of bytes for all UTF-8 versions of strings together.

    int32_t utf8Length;

    // Maximum lengths of relevant strings.

    int32_t maxLength16;

    int32_t maxLength8;

    // Set up for all variants of span()?

    UBool all;

    // Memory for small numbers and lengths of strings.

    // For example, for 8 strings:

    // 8 UTF-8 lengths, 8*4 bytes span lengths, 8*2 3-byte UTF-8 characters

    // = 112 bytes = int32_t[28].

    int32_t staticLengths[32];

};

UBool UnicodeSetStringSpan::needsStringSpanUTF16() {

    return (UBool)(maxLength16!=0);

}

UBool UnicodeSetStringSpan::needsStringSpanUTF8() {

    return (UBool)(maxLength8!=0);

}

UBool UnicodeSetStringSpan::contains(UChar32 c) const {

    return spanSet.contains(c);

}

U_NAMESPACE_END

#endif