1 // 2017 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 4 #include "unicode/utypes.h" 5 6 #if !UCONFIG_NO_FORMATTING && !UPRV_INCOMPLETE_CPP11_SUPPORT 7 #ifndef __NUMBER_AFFIXUTILS_H__ 8 #define __NUMBER_AFFIXUTILS_H__ 9 10 #include <cstdint> 11 #include "number_types.h" 12 #include "unicode/stringpiece.h" 13 #include "unicode/unistr.h" 14 #include "number_stringbuilder.h" 15 16 U_NAMESPACE_BEGIN namespace number { 17 namespace impl { 18 19 enum AffixPatternState { 20 STATE_BASE = 0, 21 STATE_FIRST_QUOTE = 1, 22 STATE_INSIDE_QUOTE = 2, 23 STATE_AFTER_QUOTE = 3, 24 STATE_FIRST_CURR = 4, 25 STATE_SECOND_CURR = 5, 26 STATE_THIRD_CURR = 6, 27 STATE_FOURTH_CURR = 7, 28 STATE_FIFTH_CURR = 8, 29 STATE_OVERFLOW_CURR = 9 30 }; 31 32 // enum AffixPatternType defined in internals.h 33 34 struct AffixTag { 35 int32_t offset; 36 UChar32 codePoint; 37 AffixPatternState state; 38 AffixPatternType type; 39 40 AffixTag() : offset(0), state(STATE_BASE) {} 41 42 AffixTag(int32_t offset) : offset(offset) {} 43 44 AffixTag(int32_t offset, UChar32 codePoint, AffixPatternState state, AffixPatternType type) 45 : offset(offset), codePoint(codePoint), state(state), type(type) 46 {} 47 }; 48 49 // Exported as U_I18N_API because it is a base class for other exported types 50 class U_I18N_API SymbolProvider { 51 public: 52 virtual ~SymbolProvider() = default; 53 54 // TODO: Could this be more efficient if it returned by reference? 55 virtual UnicodeString getSymbol(AffixPatternType type) const = 0; 56 }; 57 58 /** 59 * Performs manipulations on affix patterns: the prefix and suffix strings associated with a decimal 60 * format pattern. For example: 61 * 62 * <table> 63 * <tr><th>Affix Pattern</th><th>Example Unescaped (Formatted) String</th></tr> 64 * <tr><td>abc</td><td>abc</td></tr> 65 * <tr><td>ab-</td><td>ab</td></tr> 66 * <tr><td>ab'-'</td><td>ab-</td></tr> 67 * <tr><td>ab''</td><td>ab'</td></tr> 68 * </table> 69 * 70 * To manually iterate over tokens in a literal string, use the following pattern, which is designed 71 * to be efficient. 72 * 73 * <pre> 74 * long tag = 0L; 75 * while (AffixPatternUtils.hasNext(tag, patternString)) { 76 * tag = AffixPatternUtils.nextToken(tag, patternString); 77 * int typeOrCp = AffixPatternUtils.getTypeOrCp(tag); 78 * switch (typeOrCp) { 79 * case AffixPatternUtils.TYPE_MINUS_SIGN: 80 * // Current token is a minus sign. 81 * break; 82 * case AffixPatternUtils.TYPE_PLUS_SIGN: 83 * // Current token is a plus sign. 84 * break; 85 * case AffixPatternUtils.TYPE_PERCENT: 86 * // Current token is a percent sign. 87 * break; 88 * // ... other types ... 89 * default: 90 * // Current token is an arbitrary code point. 91 * // The variable typeOrCp is the code point. 92 * break; 93 * } 94 * } 95 * </pre> 96 */ 97 class U_I18N_API AffixUtils { 98 99 public: 100 101 /** 102 * Estimates the number of code points present in an unescaped version of the affix pattern string 103 * (one that would be returned by {@link #unescape}), assuming that all interpolated symbols 104 * consume one code point and that currencies consume as many code points as their symbol width. 105 * Used for computing padding width. 106 * 107 * @param patternString The original string whose width will be estimated. 108 * @return The length of the unescaped string. 109 */ 110 static int32_t estimateLength(const CharSequence &patternString, UErrorCode &status); 111 112 /** 113 * Takes a string and escapes (quotes) characters that have special meaning in the affix pattern 114 * syntax. This function does not reverse-lookup symbols. 115 * 116 * <p>Example input: "-$x"; example output: "'-'$x" 117 * 118 * @param input The string to be escaped. 119 * @return The resulting UnicodeString. 120 */ 121 static UnicodeString escape(const CharSequence &input); 122 123 static Field getFieldForType(AffixPatternType type); 124 125 /** 126 * Executes the unescape state machine. Replaces the unquoted characters "-", "+", "%", "", and 127 * "" with the corresponding symbols provided by the {@link SymbolProvider}, and inserts the 128 * result into the NumberStringBuilder at the requested location. 129 * 130 * <p>Example input: "'-'x"; example output: "-$x" 131 * 132 * @param affixPattern The original string to be unescaped. 133 * @param output The NumberStringBuilder to mutate with the result. 134 * @param position The index into the NumberStringBuilder to insert the string. 135 * @param provider An object to generate locale symbols. 136 */ 137 static int32_t 138 unescape(const CharSequence &affixPattern, NumberStringBuilder &output, int32_t position, 139 const SymbolProvider &provider, UErrorCode &status); 140 141 /** 142 * Sames as {@link #unescape}, but only calculates the code point count. More efficient than {@link #unescape} 143 * if you only need the length but not the string itself. 144 * 145 * @param affixPattern The original string to be unescaped. 146 * @param provider An object to generate locale symbols. 147 * @return The same return value as if you called {@link #unescape}. 148 */ 149 static int32_t unescapedCodePointCount(const CharSequence &affixPattern, 150 const SymbolProvider &provider, UErrorCode &status); 151 152 /** 153 * Checks whether the given affix pattern contains at least one token of the given type, which is 154 * one of the constants "TYPE_" in {@link AffixPatternUtils}. 155 * 156 * @param affixPattern The affix pattern to check. 157 * @param type The token type. 158 * @return true if the affix pattern contains the given token type; false otherwise. 159 */ 160 static bool 161 containsType(const CharSequence &affixPattern, AffixPatternType type, UErrorCode &status); 162 163 /** 164 * Checks whether the specified affix pattern has any unquoted currency symbols (""). 165 * 166 * @param affixPattern The string to check for currency symbols. 167 * @return true if the literal has at least one unquoted currency symbol; false otherwise. 168 */ 169 static bool hasCurrencySymbols(const CharSequence &affixPattern, UErrorCode &status); 170 171 /** 172 * Replaces all occurrences of tokens with the given type with the given replacement char. 173 * 174 * @param affixPattern The source affix pattern (does not get modified). 175 * @param type The token type. 176 * @param replacementChar The char to substitute in place of chars of the given token type. 177 * @return A string containing the new affix pattern. 178 */ 179 static UnicodeString 180 replaceType(const CharSequence &affixPattern, AffixPatternType type, char16_t replacementChar, 181 UErrorCode &status); 182 183 /** 184 * Returns the next token from the affix pattern. 185 * 186 * @param tag A bitmask used for keeping track of state from token to token. The initial value 187 * should be 0L. 188 * @param patternString The affix pattern. 189 * @return The bitmask tag to pass to the next call of this method to retrieve the following token 190 * (never negative), or -1 if there were no more tokens in the affix pattern. 191 * @see #hasNext 192 */ 193 static AffixTag nextToken(AffixTag tag, const CharSequence &patternString, UErrorCode &status); 194 195 /** 196 * Returns whether the affix pattern string has any more tokens to be retrieved from a call to 197 * {@link #nextToken}. 198 * 199 * @param tag The bitmask tag of the previous token, as returned by {@link #nextToken}. 200 * @param string The affix pattern. 201 * @return true if there are more tokens to consume; false otherwise. 202 */ 203 static bool hasNext(const AffixTag &tag, const CharSequence &string); 204 205 private: 206 /** 207 * Encodes the given values into a tag struct. 208 * The order of the arguments is consistent with Java, but the order of the stored 209 * fields is not necessarily the same. 210 */ 211 static inline AffixTag 212 makeTag(int32_t offset, AffixPatternType type, AffixPatternState state, UChar32 cp) { 213 return {offset, cp, state, type}; 214 } 215 }; 216 217 } // namespace impl 218 } // namespace number 219 U_NAMESPACE_END 220 221 222 #endif //__NUMBER_AFFIXUTILS_H__ 223 224 #endif /* #if !UCONFIG_NO_FORMATTING */ 225
