--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/unicode/localematcher.h	Tue Mar 18 17:55:14 2025 -0400
@@ -0,0 +1,665 @@
+// © 2019 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html#License
+
+// localematcher.h
+// created: 2019may08 Markus W. Scherer
+
+#ifndef __LOCALEMATCHER_H__
+#define __LOCALEMATCHER_H__
+
+#include "unicode/utypes.h"
+
+#if U_SHOW_CPLUSPLUS_API
+
+#include "unicode/locid.h"
+#include "unicode/stringpiece.h"
+#include "unicode/uobject.h"
+
+/**
+ * \file
+ * \brief C++ API: Locale matcher: User's desired locales vs. application's supported locales.
+ */
+
+#ifndef U_FORCE_HIDE_DRAFT_API
+
+/**
+ * Builder option for whether the language subtag or the script subtag is most important.
+ *
+ * @see Builder#setFavorSubtag(ULocMatchFavorSubtag)
+ * @draft ICU 65
+ */
+enum ULocMatchFavorSubtag {
+    /**
+     * Language differences are most important, then script differences, then region differences.
+     * (This is the default behavior.)
+     *
+     * @draft ICU 65
+     */
+    ULOCMATCH_FAVOR_LANGUAGE,
+    /**
+     * Makes script differences matter relatively more than language differences.
+     *
+     * @draft ICU 65
+     */
+    ULOCMATCH_FAVOR_SCRIPT
+};
+#ifndef U_IN_DOXYGEN
+typedef enum ULocMatchFavorSubtag ULocMatchFavorSubtag;
+#endif
+
+/**
+ * Builder option for whether all desired locales are treated equally or
+ * earlier ones are preferred.
+ *
+ * @see Builder#setDemotionPerDesiredLocale(ULocMatchDemotion)
+ * @draft ICU 65
+ */
+enum ULocMatchDemotion {
+    /**
+     * All desired locales are treated equally.
+     *
+     * @draft ICU 65
+     */
+    ULOCMATCH_DEMOTION_NONE,
+    /**
+     * Earlier desired locales are preferred.
+     *
+     * <p>From each desired locale to the next,
+     * the distance to any supported locale is increased by an additional amount
+     * which is at least as large as most region mismatches.
+     * A later desired locale has to have a better match with some supported locale
+     * due to more than merely having the same region subtag.
+     *
+     * <p>For example: <code>Supported={en, sv}  desired=[en-GB, sv]</code>
+     * yields <code>Result(en-GB, en)</code> because
+     * with the demotion of sv its perfect match is no better than
+     * the region distance between the earlier desired locale en-GB and en=en-US.
+     *
+     * <p>Notes:
+     * <ul>
+     *   <li>In some cases, language and/or script differences can be as small as
+     *       the typical region difference. (Example: sr-Latn vs. sr-Cyrl)
+     *   <li>It is possible for certain region differences to be larger than usual,
+     *       and larger than the demotion.
+     *       (As of CLDR 35 there is no such case, but
+     *        this is possible in future versions of the data.)
+     * </ul>
+     *
+     * @draft ICU 65
+     */
+    ULOCMATCH_DEMOTION_REGION
+};
+#ifndef U_IN_DOXYGEN
+typedef enum ULocMatchDemotion ULocMatchDemotion;
+#endif
+
+/**
+ * Builder option for whether to include or ignore one-way (fallback) match data.
+ * The LocaleMatcher uses CLDR languageMatch data which includes fallback (oneway=true) entries.
+ * Sometimes it is desirable to ignore those.
+ *
+ * <p>For example, consider a web application with the UI in a given language,
+ * with a link to another, related web app.
+ * The link should include the UI language, and the target server may also use
+ * the client’s Accept-Language header data.
+ * The target server has its own list of supported languages.
+ * One may want to favor UI language consistency, that is,
+ * if there is a decent match for the original UI language, we want to use it,
+ * but not if it is merely a fallback.
+ *
+ * @see Builder#setDirection(ULocMatchDirection)
+ * @draft ICU 67
+ */
+enum ULocMatchDirection {
+    /**
+     * Locale matching includes one-way matches such as Breton→French. (default)
+     *
+     * @draft ICU 67
+     */
+    ULOCMATCH_DIRECTION_WITH_ONE_WAY,
+    /**
+     * Locale matching limited to two-way matches including e.g. Danish↔Norwegian
+     * but ignoring one-way matches.
+     *
+     * @draft ICU 67
+     */
+    ULOCMATCH_DIRECTION_ONLY_TWO_WAY
+};
+#ifndef U_IN_DOXYGEN
+typedef enum ULocMatchDirection ULocMatchDirection;
+#endif
+
+struct UHashtable;
+
+U_NAMESPACE_BEGIN
+
+struct LSR;
+
+class LocaleDistance;
+class LocaleLsrIterator;
+class UVector;
+class XLikelySubtags;
+
+/**
+ * Immutable class that picks the best match between a user's desired locales and
+ * an application's supported locales.
+ * Movable but not copyable.
+ *
+ * <p>Example:
+ * <pre>
+ * UErrorCode errorCode = U_ZERO_ERROR;
+ * LocaleMatcher matcher = LocaleMatcher::Builder().setSupportedLocales("fr, en-GB, en").build(errorCode);
+ * Locale *bestSupported = matcher.getBestLocale(Locale.US, errorCode);  // "en"
+ * </pre>
+ *
+ * <p>A matcher takes into account when languages are close to one another,
+ * such as Danish and Norwegian,
+ * and when regional variants are close, like en-GB and en-AU as opposed to en-US.
+ *
+ * <p>If there are multiple supported locales with the same (language, script, region)
+ * likely subtags, then the current implementation returns the first of those locales.
+ * It ignores variant subtags (except for pseudolocale variants) and extensions.
+ * This may change in future versions.
+ *
+ * <p>For example, the current implementation does not distinguish between
+ * de, de-DE, de-Latn, de-1901, de-u-co-phonebk.
+ *
+ * <p>If you prefer one equivalent locale over another, then provide only the preferred one,
+ * or place it earlier in the list of supported locales.
+ *
+ * <p>Otherwise, the order of supported locales may have no effect on the best-match results.
+ * The current implementation compares each desired locale with supported locales
+ * in the following order:
+ * 1. Default locale, if supported;
+ * 2. CLDR "paradigm locales" like en-GB and es-419;
+ * 3. other supported locales.
+ * This may change in future versions.
+ *
+ * <p>Often a product will just need one matcher instance, built with the languages
+ * that it supports. However, it may want multiple instances with different
+ * default languages based on additional information, such as the domain.
+ *
+ * <p>This class is not intended for public subclassing.
+ *
+ * @draft ICU 65
+ */
+class U_COMMON_API LocaleMatcher : public UMemory {
+public:
+    /**
+     * Data for the best-matching pair of a desired and a supported locale.
+     * Movable but not copyable.
+     *
+     * @draft ICU 65
+     */
+    class U_COMMON_API Result : public UMemory {
+    public:
+        /**
+         * Move constructor; might modify the source.
+         * This object will have the same contents that the source object had.
+         *
+         * @param src Result to move contents from.
+         * @draft ICU 65
+         */
+        Result(Result &&src) U_NOEXCEPT;
+
+        /**
+         * Destructor.
+         *
+         * @draft ICU 65
+         */
+        ~Result();
+
+        /**
+         * Move assignment; might modify the source.
+         * This object will have the same contents that the source object had.
+         *
+         * @param src Result to move contents from.
+         * @draft ICU 65
+         */
+        Result &operator=(Result &&src) U_NOEXCEPT;
+
+#ifndef U_HIDE_DRAFT_API
+        /**
+         * Returns the best-matching desired locale.
+         * nullptr if the list of desired locales is empty or if none matched well enough.
+         *
+         * @return the best-matching desired locale, or nullptr.
+         * @draft ICU 65
+         */
+        inline const Locale *getDesiredLocale() const { return desiredLocale; }
+
+        /**
+         * Returns the best-matching supported locale.
+         * If none matched well enough, this is the default locale.
+         * The default locale is nullptr if the list of supported locales is empty and
+         * no explicit default locale is set.
+         *
+         * @return the best-matching supported locale, or nullptr.
+         * @draft ICU 65
+         */
+        inline const Locale *getSupportedLocale() const { return supportedLocale; }
+
+        /**
+         * Returns the index of the best-matching desired locale in the input Iterable order.
+         * -1 if the list of desired locales is empty or if none matched well enough.
+         *
+         * @return the index of the best-matching desired locale, or -1.
+         * @draft ICU 65
+         */
+        inline int32_t getDesiredIndex() const { return desiredIndex; }
+
+        /**
+         * Returns the index of the best-matching supported locale in the
+         * constructor’s or builder’s input order (“set” Collection plus “added” locales).
+         * If the matcher was built from a locale list string, then the iteration order is that
+         * of a LocalePriorityList built from the same string.
+         * -1 if the list of supported locales is empty or if none matched well enough.
+         *
+         * @return the index of the best-matching supported locale, or -1.
+         * @draft ICU 65
+         */
+        inline int32_t getSupportedIndex() const { return supportedIndex; }
+
+        /**
+         * Takes the best-matching supported locale and adds relevant fields of the
+         * best-matching desired locale, such as the -t- and -u- extensions.
+         * May replace some fields of the supported locale.
+         * The result is the locale that should be used for date and number formatting, collation, etc.
+         * Returns the root locale if getSupportedLocale() returns nullptr.
+         *
+         * <p>Example: desired=ar-SA-u-nu-latn, supported=ar-EG, resolved locale=ar-SA-u-nu-latn
+         *
+         * @return a locale combining the best-matching desired and supported locales.
+         * @draft ICU 65
+         */
+        Locale makeResolvedLocale(UErrorCode &errorCode) const;
+#endif  // U_HIDE_DRAFT_API
+
+    private:
+        Result(const Locale *desired, const Locale *supported,
+               int32_t desIndex, int32_t suppIndex, UBool owned) :
+                desiredLocale(desired), supportedLocale(supported),
+                desiredIndex(desIndex), supportedIndex(suppIndex),
+                desiredIsOwned(owned) {}
+
+        Result(const Result &other) = delete;
+        Result &operator=(const Result &other) = delete;
+
+        const Locale *desiredLocale;
+        const Locale *supportedLocale;
+        int32_t desiredIndex;
+        int32_t supportedIndex;
+        UBool desiredIsOwned;
+
+        friend class LocaleMatcher;
+    };
+
+    /**
+     * LocaleMatcher builder.
+     * Movable but not copyable.
+     *
+     * @see LocaleMatcher#builder()
+     * @draft ICU 65
+     */
+    class U_COMMON_API Builder : public UMemory {
+    public:
+        /**
+         * Constructs a builder used in chaining parameters for building a LocaleMatcher.
+         *
+         * @return a new Builder object
+         * @draft ICU 65
+         */
+        Builder() {}
+
+        /**
+         * Move constructor; might modify the source.
+         * This builder will have the same contents that the source builder had.
+         *
+         * @param src Builder to move contents from.
+         * @draft ICU 65
+         */
+        Builder(Builder &&src) U_NOEXCEPT;
+
+        /**
+         * Destructor.
+         *
+         * @draft ICU 65
+         */
+        ~Builder();
+
+        /**
+         * Move assignment; might modify the source.
+         * This builder will have the same contents that the source builder had.
+         *
+         * @param src Builder to move contents from.
+         * @draft ICU 65
+         */
+        Builder &operator=(Builder &&src) U_NOEXCEPT;
+
+#ifndef U_HIDE_DRAFT_API
+        /**
+         * Parses an Accept-Language string
+         * (<a href="https://tools.ietf.org/html/rfc2616#section-14.4">RFC 2616 Section 14.4</a>),
+         * such as "af, en, fr;q=0.9", and sets the supported locales accordingly.
+         * Allows whitespace in more places but does not allow "*".
+         * Clears any previously set/added supported locales first.
+         *
+         * @param locales the Accept-Language string of locales to set
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        Builder &setSupportedLocalesFromListString(StringPiece locales);
+
+        /**
+         * Copies the supported locales, preserving iteration order.
+         * Clears any previously set/added supported locales first.
+         * Duplicates are allowed, and are not removed.
+         *
+         * @param locales the list of locale
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        Builder &setSupportedLocales(Locale::Iterator &locales);
+
+        /**
+         * Copies the supported locales from the begin/end range, preserving iteration order.
+         * Clears any previously set/added supported locales first.
+         * Duplicates are allowed, and are not removed.
+         *
+         * Each of the iterator parameter values must be an
+         * input iterator whose value is convertible to const Locale &.
+         *
+         * @param begin Start of range.
+         * @param end Exclusive end of range.
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        template<typename Iter>
+        Builder &setSupportedLocales(Iter begin, Iter end) {
+            if (U_FAILURE(errorCode_)) { return *this; }
+            clearSupportedLocales();
+            while (begin != end) {
+                addSupportedLocale(*begin++);
+            }
+            return *this;
+        }
+
+        /**
+         * Copies the supported locales from the begin/end range, preserving iteration order.
+         * Calls the converter to convert each *begin to a Locale or const Locale &.
+         * Clears any previously set/added supported locales first.
+         * Duplicates are allowed, and are not removed.
+         *
+         * Each of the iterator parameter values must be an
+         * input iterator whose value is convertible to const Locale &.
+         *
+         * @param begin Start of range.
+         * @param end Exclusive end of range.
+         * @param converter Converter from *begin to const Locale & or compatible.
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        template<typename Iter, typename Conv>
+        Builder &setSupportedLocalesViaConverter(Iter begin, Iter end, Conv converter) {
+            if (U_FAILURE(errorCode_)) { return *this; }
+            clearSupportedLocales();
+            while (begin != end) {
+                addSupportedLocale(converter(*begin++));
+            }
+            return *this;
+        }
+
+        /**
+         * Adds another supported locale.
+         * Duplicates are allowed, and are not removed.
+         *
+         * @param locale another locale
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        Builder &addSupportedLocale(const Locale &locale);
+
+        /**
+         * Sets the default locale; if nullptr, or if it is not set explicitly,
+         * then the first supported locale is used as the default locale.
+         *
+         * @param defaultLocale the default locale (will be copied)
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        Builder &setDefaultLocale(const Locale *defaultLocale);
+
+        /**
+         * If ULOCMATCH_FAVOR_SCRIPT, then the language differences are smaller than script
+         * differences.
+         * This is used in situations (such as maps) where
+         * it is better to fall back to the same script than a similar language.
+         *
+         * @param subtag the subtag to favor
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        Builder &setFavorSubtag(ULocMatchFavorSubtag subtag);
+
+        /**
+         * Option for whether all desired locales are treated equally or
+         * earlier ones are preferred (this is the default).
+         *
+         * @param demotion the demotion per desired locale to set.
+         * @return this Builder object
+         * @draft ICU 65
+         */
+        Builder &setDemotionPerDesiredLocale(ULocMatchDemotion demotion);
+
+        /**
+         * Option for whether to include or ignore one-way (fallback) match data.
+         * By default, they are included.
+         *
+         * @param direction the match direction to set.
+         * @return this Builder object
+         * @draft ICU 67
+         */
+        Builder &setDirection(ULocMatchDirection direction) {
+            if (U_SUCCESS(errorCode_)) {
+                direction_ = direction;
+            }
+            return *this;
+        }
+
+        /**
+         * Sets the UErrorCode if an error occurred while setting parameters.
+         * Preserves older error codes in the outErrorCode.
+         *
+         * @param outErrorCode Set to an error code if it does not contain one already
+         *                  and an error occurred while setting parameters.
+         *                  Otherwise unchanged.
+         * @return TRUE if U_FAILURE(outErrorCode)
+         * @draft ICU 65
+         */
+        UBool copyErrorTo(UErrorCode &outErrorCode) const;
+
+        /**
+         * Builds and returns a new locale matcher.
+         * This builder can continue to be used.
+         *
+         * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+         *                  or else the function returns immediately. Check for U_FAILURE()
+         *                  on output or use with function chaining. (See User Guide for details.)
+         * @return new LocaleMatcher.
+         * @draft ICU 65
+         */
+        LocaleMatcher build(UErrorCode &errorCode) const;
+#endif  // U_HIDE_DRAFT_API
+
+    private:
+        friend class LocaleMatcher;
+
+        Builder(const Builder &other) = delete;
+        Builder &operator=(const Builder &other) = delete;
+
+        void clearSupportedLocales();
+        bool ensureSupportedLocaleVector();
+
+        UErrorCode errorCode_ = U_ZERO_ERROR;
+        UVector *supportedLocales_ = nullptr;
+        int32_t thresholdDistance_ = -1;
+        ULocMatchDemotion demotion_ = ULOCMATCH_DEMOTION_REGION;
+        Locale *defaultLocale_ = nullptr;
+        ULocMatchFavorSubtag favor_ = ULOCMATCH_FAVOR_LANGUAGE;
+        ULocMatchDirection direction_ = ULOCMATCH_DIRECTION_WITH_ONE_WAY;
+    };
+
+    // FYI No public LocaleMatcher constructors in C++; use the Builder.
+
+    /**
+     * Move copy constructor; might modify the source.
+     * This matcher will have the same settings that the source matcher had.
+     * @param src source matcher
+     * @draft ICU 65
+     */
+    LocaleMatcher(LocaleMatcher &&src) U_NOEXCEPT;
+
+    /**
+     * Destructor.
+     * @draft ICU 65
+     */
+    ~LocaleMatcher();
+
+    /**
+     * Move assignment operator; might modify the source.
+     * This matcher will have the same settings that the source matcher had.
+     * The behavior is undefined if *this and src are the same object.
+     * @param src source matcher
+     * @return *this
+     * @draft ICU 65
+     */
+    LocaleMatcher &operator=(LocaleMatcher &&src) U_NOEXCEPT;
+
+#ifndef U_HIDE_DRAFT_API
+    /**
+     * Returns the supported locale which best matches the desired locale.
+     *
+     * @param desiredLocale Typically a user's language.
+     * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+     *                  or else the function returns immediately. Check for U_FAILURE()
+     *                  on output or use with function chaining. (See User Guide for details.)
+     * @return the best-matching supported locale.
+     * @draft ICU 65
+     */
+    const Locale *getBestMatch(const Locale &desiredLocale, UErrorCode &errorCode) const;
+
+    /**
+     * Returns the supported locale which best matches one of the desired locales.
+     *
+     * @param desiredLocales Typically a user's languages, in order of preference (descending).
+     * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+     *                  or else the function returns immediately. Check for U_FAILURE()
+     *                  on output or use with function chaining. (See User Guide for details.)
+     * @return the best-matching supported locale.
+     * @draft ICU 65
+     */
+    const Locale *getBestMatch(Locale::Iterator &desiredLocales, UErrorCode &errorCode) const;
+
+    /**
+     * Parses an Accept-Language string
+     * (<a href="https://tools.ietf.org/html/rfc2616#section-14.4">RFC 2616 Section 14.4</a>),
+     * such as "af, en, fr;q=0.9",
+     * and returns the supported locale which best matches one of the desired locales.
+     * Allows whitespace in more places but does not allow "*".
+     *
+     * @param desiredLocaleList Typically a user's languages, as an Accept-Language string.
+     * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+     *                  or else the function returns immediately. Check for U_FAILURE()
+     *                  on output or use with function chaining. (See User Guide for details.)
+     * @return the best-matching supported locale.
+     * @draft ICU 65
+     */
+    const Locale *getBestMatchForListString(StringPiece desiredLocaleList, UErrorCode &errorCode) const;
+
+    /**
+     * Returns the best match between the desired locale and the supported locales.
+     * If the result's desired locale is not nullptr, then it is the address of the input locale.
+     * It has not been cloned.
+     *
+     * @param desiredLocale Typically a user's language.
+     * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+     *                  or else the function returns immediately. Check for U_FAILURE()
+     *                  on output or use with function chaining. (See User Guide for details.)
+     * @return the best-matching pair of the desired and a supported locale.
+     * @draft ICU 65
+     */
+    Result getBestMatchResult(const Locale &desiredLocale, UErrorCode &errorCode) const;
+
+    /**
+     * Returns the best match between the desired and supported locales.
+     * If the result's desired locale is not nullptr, then it is a clone of
+     * the best-matching desired locale. The Result object owns the clone.
+     *
+     * @param desiredLocales Typically a user's languages, in order of preference (descending).
+     * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+     *                  or else the function returns immediately. Check for U_FAILURE()
+     *                  on output or use with function chaining. (See User Guide for details.)
+     * @return the best-matching pair of a desired and a supported locale.
+     * @draft ICU 65
+     */
+    Result getBestMatchResult(Locale::Iterator &desiredLocales, UErrorCode &errorCode) const;
+#endif  // U_HIDE_DRAFT_API
+
+#ifndef U_HIDE_INTERNAL_API
+    /**
+     * Returns a fraction between 0 and 1, where 1 means that the languages are a
+     * perfect match, and 0 means that they are completely different.
+     *
+     * <p>This is mostly an implementation detail, and the precise values may change over time.
+     * The implementation may use either the maximized forms or the others ones, or both.
+     * The implementation may or may not rely on the forms to be consistent with each other.
+     *
+     * <p>Callers should construct and use a matcher rather than match pairs of locales directly.
+     *
+     * @param desired Desired locale.
+     * @param supported Supported locale.
+     * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+     *                  or else the function returns immediately. Check for U_FAILURE()
+     *                  on output or use with function chaining. (See User Guide for details.)
+     * @return value between 0 and 1, inclusive.
+     * @internal (has a known user)
+     */
+    double internalMatch(const Locale &desired, const Locale &supported, UErrorCode &errorCode) const;
+#endif  // U_HIDE_INTERNAL_API
+
+private:
+    LocaleMatcher(const Builder &builder, UErrorCode &errorCode);
+    LocaleMatcher(const LocaleMatcher &other) = delete;
+    LocaleMatcher &operator=(const LocaleMatcher &other) = delete;
+
+    int32_t putIfAbsent(const LSR &lsr, int32_t i, int32_t suppLength, UErrorCode &errorCode);
+
+    int32_t getBestSuppIndex(LSR desiredLSR, LocaleLsrIterator *remainingIter, UErrorCode &errorCode) const;
+
+    const XLikelySubtags &likelySubtags;
+    const LocaleDistance &localeDistance;
+    int32_t thresholdDistance;
+    int32_t demotionPerDesiredLocale;
+    ULocMatchFavorSubtag favorSubtag;
+    ULocMatchDirection direction;
+
+    // These are in input order.
+    const Locale ** supportedLocales;
+    LSR *lsrs;
+    int32_t supportedLocalesLength;
+    // These are in preference order: 1. Default locale 2. paradigm locales 3. others.
+    UHashtable *supportedLsrToIndex;  // Map<LSR, Integer> stores index+1 because 0 is "not found"
+    // Array versions of the supportedLsrToIndex keys and values.
+    // The distance lookup loops over the supportedLSRs and returns the index of the best match.
+    const LSR **supportedLSRs;
+    int32_t *supportedIndexes;
+    int32_t supportedLSRsLength;
+    Locale *ownedDefaultLocale;
+    const Locale *defaultLocale;
+};
+
+U_NAMESPACE_END
+
+#endif  // U_FORCE_HIDE_DRAFT_API
+#endif  // U_SHOW_CPLUSPLUS_API
+#endif  // __LOCALEMATCHER_H__