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

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

/*

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

* Copyright (C) 2013-2014, International Business Machines

* Corporation and others.  All Rights Reserved.

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

* collationruleparser.h

*

* created on: 2013apr10

* created by: Markus W. Scherer

*/

#ifndef __COLLATIONRULEPARSER_H__

#define __COLLATIONRULEPARSER_H__

#include "unicode/utypes.h"

#if !UCONFIG_NO_COLLATION

#include "unicode/ucol.h"

#include "unicode/uniset.h"

#include "unicode/unistr.h"

struct UParseError;

U_NAMESPACE_BEGIN

struct CollationData;

struct CollationTailoring;

class Locale;

class Normalizer2;

struct CollationSettings;

class U_I18N_API CollationRuleParser : public UMemory {

public:

    /** Special reset positions. */

    enum Position {

        FIRST_TERTIARY_IGNORABLE,

        LAST_TERTIARY_IGNORABLE,

        FIRST_SECONDARY_IGNORABLE,

        LAST_SECONDARY_IGNORABLE,

        FIRST_PRIMARY_IGNORABLE,

        LAST_PRIMARY_IGNORABLE,

        FIRST_VARIABLE,

        LAST_VARIABLE,

        FIRST_REGULAR,

        LAST_REGULAR,

        FIRST_IMPLICIT,

        LAST_IMPLICIT,

        FIRST_TRAILING,

        LAST_TRAILING

    };

    /**

     * First character of contractions that encode special reset positions.

     * U+FFFE cannot be tailored via rule syntax.

     *

     * The second contraction character is POS_BASE + Position.

     */

    static const UChar POS_LEAD = 0xfffe;

    /**

     * Base for the second character of contractions that encode special reset positions.

     * Braille characters U+28xx are printable and normalization-inert.

     * @see POS_LEAD

     */

    static const UChar POS_BASE = 0x2800;

    class U_I18N_API Sink : public UObject {

    public:

        virtual ~Sink();

        /**

         * Adds a reset.

         * strength=UCOL_IDENTICAL for &str.

         * strength=UCOL_PRIMARY/UCOL_SECONDARY/UCOL_TERTIARY for &[before n]str where n=1/2/3.

         */

        virtual void addReset(int32_t strength, const UnicodeString &str,

                              const char *&errorReason, UErrorCode &errorCode) = 0;

        /**

         * Adds a relation with strength and prefix | str / extension.

         */

        virtual void addRelation(int32_t strength, const UnicodeString &prefix,

                                 const UnicodeString &str, const UnicodeString &extension,

                                 const char *&errorReason, UErrorCode &errorCode) = 0;

        virtual void suppressContractions(const UnicodeSet &set, const char *&errorReason,

                                          UErrorCode &errorCode);

        virtual void optimize(const UnicodeSet &set, const char *&errorReason,

                              UErrorCode &errorCode);

    };

    class U_I18N_API Importer : public UObject {

    public:

        virtual ~Importer();

        virtual void getRules(

                const char *localeID, const char *collationType,

                UnicodeString &rules,

                const char *&errorReason, UErrorCode &errorCode) = 0;

    };

    /**

     * Constructor.

     * The Sink must be set before parsing.

     * The Importer can be set, otherwise [import locale] syntax is not supported.

     */

    CollationRuleParser(const CollationData *base, UErrorCode &errorCode);

    ~CollationRuleParser();

    /**

     * Sets the pointer to a Sink object.

     * The pointer is aliased: Pointer copy without cloning or taking ownership.

     */

    void setSink(Sink *sinkAlias) {

        sink = sinkAlias;

    }

    /**

     * Sets the pointer to an Importer object.

     * The pointer is aliased: Pointer copy without cloning or taking ownership.

     */

    void setImporter(Importer *importerAlias) {

        importer = importerAlias;

    }

    void parse(const UnicodeString &ruleString,

               CollationSettings &outSettings,

               UParseError *outParseError,

               UErrorCode &errorCode);

    const char *getErrorReason() const { return errorReason; }

    /**

     * Gets a script or reorder code from its string representation.

     * @return the script/reorder code, or

     * -1 if not recognized

     */

    static int32_t getReorderCode(const char *word);

private:

    /** UCOL_PRIMARY=0 .. UCOL_IDENTICAL=15 */

    static const int32_t STRENGTH_MASK = 0xf;

    static const int32_t STARRED_FLAG = 0x10;

    static const int32_t OFFSET_SHIFT = 8;

    void parse(const UnicodeString &ruleString, UErrorCode &errorCode);

    void parseRuleChain(UErrorCode &errorCode);

    int32_t parseResetAndPosition(UErrorCode &errorCode);

    int32_t parseRelationOperator(UErrorCode &errorCode);

    void parseRelationStrings(int32_t strength, int32_t i, UErrorCode &errorCode);

    void parseStarredCharacters(int32_t strength, int32_t i, UErrorCode &errorCode);

    int32_t parseTailoringString(int32_t i, UnicodeString &raw, UErrorCode &errorCode);

    int32_t parseString(int32_t i, UnicodeString &raw, UErrorCode &errorCode);

    /**

     * Sets str to a contraction of U+FFFE and (U+2800 + Position).

     * @return rule index after the special reset position

     */

    int32_t parseSpecialPosition(int32_t i, UnicodeString &str, UErrorCode &errorCode);

    void parseSetting(UErrorCode &errorCode);

    void parseReordering(const UnicodeString &raw, UErrorCode &errorCode);

    static UColAttributeValue getOnOffValue(const UnicodeString &s);

    int32_t parseUnicodeSet(int32_t i, UnicodeSet &set, UErrorCode &errorCode);

    int32_t readWords(int32_t i, UnicodeString &raw) const;

    int32_t skipComment(int32_t i) const;

    void setParseError(const char *reason, UErrorCode &errorCode);

    void setErrorContext();

    /**

     * ASCII [:P:] and [:S:]:

     * [\u0021-\u002F \u003A-\u0040 \u005B-\u0060 \u007B-\u007E]

     */

    static UBool isSyntaxChar(UChar32 c);

    int32_t skipWhiteSpace(int32_t i) const;

    const Normalizer2 &nfd, &nfc;

    const UnicodeString *rules;

    const CollationData *const baseData;

    CollationSettings *settings;

    UParseError *parseError;

    const char *errorReason;

    Sink *sink;

    Importer *importer;

    int32_t ruleIndex;

};

U_NAMESPACE_END

#endif  // !UCONFIG_NO_COLLATION

#endif  // __COLLATIONRULEPARSER_H__