// © 2018 and later: Unicode, Inc. and others.

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

#include "unicode/utypes.h"

#if !UCONFIG_NO_FORMATTING

// Allow implicit conversion from char16_t* to UnicodeString for this file:

// Helpful in toString methods and elsewhere.

#define UNISTR_FROM_STRING_EXPLICIT

#include "numparse_types.h"

#include "numparse_affixes.h"

#include "numparse_utils.h"

#include "number_utils.h"

#include "string_segment.h"

using namespace icu;

using namespace icu::numparse;

using namespace icu::numparse::impl;

using namespace icu::number;

using namespace icu::number::impl;

namespace {

/**

 * Helper method to return whether the given AffixPatternMatcher equals the given pattern string.

 * Either both arguments must be null or the pattern string inside the AffixPatternMatcher must equal

 * the given pattern string.

 */

static bool matched(const AffixPatternMatcher* affix, const UnicodeString& patternString) {

    return (affix == nullptr && patternString.isBogus()) ||

           (affix != nullptr && affix->getPattern() == patternString);

}

/**

 * Helper method to return the length of the given AffixPatternMatcher. Returns 0 for null.

 */

static int32_t length(const AffixPatternMatcher* matcher) {

    return matcher == nullptr ? 0 : matcher->getPattern().length();

}

/**

 * Helper method to return whether (1) both lhs and rhs are null/invalid, or (2) if they are both

 * valid, whether they are equal according to operator==.  Similar to Java Objects.equals()

 */

static bool equals(const AffixPatternMatcher* lhs, const AffixPatternMatcher* rhs) {

    if (lhs == nullptr && rhs == nullptr) {

        return true;

    }

    if (lhs == nullptr || rhs == nullptr) {

        return false;

    }

    return *lhs == *rhs;

}

}

AffixPatternMatcherBuilder::AffixPatternMatcherBuilder(const UnicodeString& pattern,

                                                       AffixTokenMatcherWarehouse& warehouse,

                                                       IgnorablesMatcher* ignorables)

        : fMatchersLen(0),

          fLastTypeOrCp(0),

          fPattern(pattern),

          fWarehouse(warehouse),

          fIgnorables(ignorables) {}

void AffixPatternMatcherBuilder::consumeToken(AffixPatternType type, UChar32 cp, UErrorCode& status) {

    // This is called by AffixUtils.iterateWithConsumer() for each token.

    // Add an ignorables matcher between tokens except between two literals, and don't put two

    // ignorables matchers in a row.

    if (fIgnorables != nullptr && fMatchersLen > 0 &&

        (fLastTypeOrCp < 0 || !fIgnorables->getSet()->contains(fLastTypeOrCp))) {

        addMatcher(*fIgnorables);

    }

    if (type != TYPE_CODEPOINT) {

        // Case 1: the token is a symbol.

        switch (type) {

            case TYPE_MINUS_SIGN:

                addMatcher(fWarehouse.minusSign());

                break;

            case TYPE_PLUS_SIGN:

                addMatcher(fWarehouse.plusSign());

                break;

            case TYPE_PERCENT:

                addMatcher(fWarehouse.percent());

                break;

            case TYPE_PERMILLE:

                addMatcher(fWarehouse.permille());

                break;

            case TYPE_CURRENCY_SINGLE:

            case TYPE_CURRENCY_DOUBLE:

            case TYPE_CURRENCY_TRIPLE:

            case TYPE_CURRENCY_QUAD:

            case TYPE_CURRENCY_QUINT:

                // All currency symbols use the same matcher

                addMatcher(fWarehouse.currency(status));

                break;

            default:

                UPRV_UNREACHABLE;

        }

    } else if (fIgnorables != nullptr && fIgnorables->getSet()->contains(cp)) {

        // Case 2: the token is an ignorable literal.

        // No action necessary: the ignorables matcher has already been added.

    } else {

        // Case 3: the token is a non-ignorable literal.

        if (auto* ptr = fWarehouse.nextCodePointMatcher(cp, status)) {

            addMatcher(*ptr);

        } else {

            // OOM; unwind the stack

            return;

        }

    }

    fLastTypeOrCp = type != TYPE_CODEPOINT ? type : cp;

}

void AffixPatternMatcherBuilder::addMatcher(NumberParseMatcher& matcher) {

    if (fMatchersLen >= fMatchers.getCapacity()) {

        fMatchers.resize(fMatchersLen * 2, fMatchersLen);

    }

    fMatchers[fMatchersLen++] = &matcher;

}

AffixPatternMatcher AffixPatternMatcherBuilder::build(UErrorCode& status) {

    return AffixPatternMatcher(fMatchers, fMatchersLen, fPattern, status);

}

AffixTokenMatcherWarehouse::AffixTokenMatcherWarehouse(const AffixTokenMatcherSetupData* setupData)

        : fSetupData(setupData) {}

NumberParseMatcher& AffixTokenMatcherWarehouse::minusSign() {

    return fMinusSign = {fSetupData->dfs, true};

}

NumberParseMatcher& AffixTokenMatcherWarehouse::plusSign() {

    return fPlusSign = {fSetupData->dfs, true};

}

NumberParseMatcher& AffixTokenMatcherWarehouse::percent() {

    return fPercent = {fSetupData->dfs};

}

NumberParseMatcher& AffixTokenMatcherWarehouse::permille() {

    return fPermille = {fSetupData->dfs};

}

NumberParseMatcher& AffixTokenMatcherWarehouse::currency(UErrorCode& status) {

    return fCurrency = {fSetupData->currencySymbols, fSetupData->dfs, fSetupData->parseFlags, status};

}

IgnorablesMatcher& AffixTokenMatcherWarehouse::ignorables() {

    return fSetupData->ignorables;

}

NumberParseMatcher* AffixTokenMatcherWarehouse::nextCodePointMatcher(UChar32 cp, UErrorCode& status) {

    if (U_FAILURE(status)) {

        return nullptr;

    }

    auto* result = fCodePoints.create(cp);

    if (result == nullptr) {

        status = U_MEMORY_ALLOCATION_ERROR;

    }

    return result;

}

CodePointMatcher::CodePointMatcher(UChar32 cp)

        : fCp(cp) {}

bool CodePointMatcher::match(StringSegment& segment, ParsedNumber& result, UErrorCode&) const {

    if (segment.startsWith(fCp)) {

        segment.adjustOffsetByCodePoint();

        result.setCharsConsumed(segment);

    }

    return false;

}

bool CodePointMatcher::smokeTest(const StringSegment& segment) const {

    return segment.startsWith(fCp);

}

UnicodeString CodePointMatcher::toString() const {

    return u"<CodePoint>";

}

AffixPatternMatcher AffixPatternMatcher::fromAffixPattern(const UnicodeString& affixPattern,

                                                          AffixTokenMatcherWarehouse& tokenWarehouse,

                                                          parse_flags_t parseFlags, bool* success,

                                                          UErrorCode& status) {

    if (affixPattern.isEmpty()) {

        *success = false;

        return {};

    }

    *success = true;

    IgnorablesMatcher* ignorables;

    if (0 != (parseFlags & PARSE_FLAG_EXACT_AFFIX)) {

        ignorables = nullptr;

    } else {

        ignorables = &tokenWarehouse.ignorables();

    }

    AffixPatternMatcherBuilder builder(affixPattern, tokenWarehouse, ignorables);

    AffixUtils::iterateWithConsumer(affixPattern, builder, status);

    return builder.build(status);

}

AffixPatternMatcher::AffixPatternMatcher(MatcherArray& matchers, int32_t matchersLen,

                                         const UnicodeString& pattern, UErrorCode& status)

    : ArraySeriesMatcher(matchers, matchersLen), fPattern(pattern, status) {

}

UnicodeString AffixPatternMatcher::getPattern() const {

    return fPattern.toAliasedUnicodeString();

}

bool AffixPatternMatcher::operator==(const AffixPatternMatcher& other) const {

    return fPattern == other.fPattern;

}

AffixMatcherWarehouse::AffixMatcherWarehouse(AffixTokenMatcherWarehouse* tokenWarehouse)

        : fTokenWarehouse(tokenWarehouse) {

}

bool AffixMatcherWarehouse::isInteresting(const AffixPatternProvider& patternInfo,

                                          const IgnorablesMatcher& ignorables, parse_flags_t parseFlags,

                                          UErrorCode& status) {

    UnicodeString posPrefixString = patternInfo.getString(AffixPatternProvider::AFFIX_POS_PREFIX);

    UnicodeString posSuffixString = patternInfo.getString(AffixPatternProvider::AFFIX_POS_SUFFIX);

    UnicodeString negPrefixString;

    UnicodeString negSuffixString;

    if (patternInfo.hasNegativeSubpattern()) {

        negPrefixString = patternInfo.getString(AffixPatternProvider::AFFIX_NEG_PREFIX);

        negSuffixString = patternInfo.getString(AffixPatternProvider::AFFIX_NEG_SUFFIX);

    }

    if (0 == (parseFlags & PARSE_FLAG_USE_FULL_AFFIXES) &&

        AffixUtils::containsOnlySymbolsAndIgnorables(posPrefixString, *ignorables.getSet(), status) &&

        AffixUtils::containsOnlySymbolsAndIgnorables(posSuffixString, *ignorables.getSet(), status) &&

        AffixUtils::containsOnlySymbolsAndIgnorables(negPrefixString, *ignorables.getSet(), status) &&

        AffixUtils::containsOnlySymbolsAndIgnorables(negSuffixString, *ignorables.getSet(), status)

        // HACK: Plus and minus sign are a special case: we accept them trailing only if they are

        // trailing in the pattern string.

        && !AffixUtils::containsType(posSuffixString, TYPE_PLUS_SIGN, status) &&

        !AffixUtils::containsType(posSuffixString, TYPE_MINUS_SIGN, status) &&

        !AffixUtils::containsType(negSuffixString, TYPE_PLUS_SIGN, status) &&

        !AffixUtils::containsType(negSuffixString, TYPE_MINUS_SIGN, status)) {

        // The affixes contain only symbols and ignorables.

        // No need to generate affix matchers.

        return false;

    }

    return true;

}

void AffixMatcherWarehouse::createAffixMatchers(const AffixPatternProvider& patternInfo,

                                                MutableMatcherCollection& output,

                                                const IgnorablesMatcher& ignorables,

                                                parse_flags_t parseFlags, UErrorCode& status) {

    if (!isInteresting(patternInfo, ignorables, parseFlags, status)) {

        return;

    }

    // The affixes have interesting characters, or we are in strict mode.

    // Use initial capacity of 6, the highest possible number of AffixMatchers.

    UnicodeString sb;

    bool includeUnpaired = 0 != (parseFlags & PARSE_FLAG_INCLUDE_UNPAIRED_AFFIXES);

    int32_t numAffixMatchers = 0;

    int32_t numAffixPatternMatchers = 0;

    AffixPatternMatcher* posPrefix = nullptr;

    AffixPatternMatcher* posSuffix = nullptr;

    // Pre-process the affix strings to resolve LDML rules like sign display.

    for (int8_t typeInt = 0; typeInt < PATTERN_SIGN_TYPE_COUNT; typeInt++) {

        auto type = static_cast<PatternSignType>(typeInt);

        // Skip affixes in some cases

        if (type == PATTERN_SIGN_TYPE_POS

                && 0 != (parseFlags & PARSE_FLAG_PLUS_SIGN_ALLOWED)) {

            continue;

        }

        if (type == PATTERN_SIGN_TYPE_POS_SIGN

                && 0 == (parseFlags & PARSE_FLAG_PLUS_SIGN_ALLOWED)) {

            continue;

        }

        // Generate Prefix

        // TODO: Handle approximately sign?

        bool hasPrefix = false;

        PatternStringUtils::patternInfoToStringBuilder(

                patternInfo, true, type, false, StandardPlural::OTHER, false, sb);

        fAffixPatternMatchers[numAffixPatternMatchers] = AffixPatternMatcher::fromAffixPattern(

                sb, *fTokenWarehouse, parseFlags, &hasPrefix, status);

        AffixPatternMatcher* prefix = hasPrefix ? &fAffixPatternMatchers[numAffixPatternMatchers++]

                                                : nullptr;

        // Generate Suffix

        // TODO: Handle approximately sign?

        bool hasSuffix = false;

        PatternStringUtils::patternInfoToStringBuilder(

                patternInfo, false, type, false, StandardPlural::OTHER, false, sb);

        fAffixPatternMatchers[numAffixPatternMatchers] = AffixPatternMatcher::fromAffixPattern(

                sb, *fTokenWarehouse, parseFlags, &hasSuffix, status);

        AffixPatternMatcher* suffix = hasSuffix ? &fAffixPatternMatchers[numAffixPatternMatchers++]

                                                : nullptr;

        if (type == PATTERN_SIGN_TYPE_POS) {

            posPrefix = prefix;

            posSuffix = suffix;

        } else if (equals(prefix, posPrefix) && equals(suffix, posSuffix)) {

            // Skip adding these matchers (we already have equivalents)

            continue;

        }

        // Flags for setting in the ParsedNumber; the token matchers may add more.

        int flags = (type == PATTERN_SIGN_TYPE_NEG) ? FLAG_NEGATIVE : 0;

        // Note: it is indeed possible for posPrefix and posSuffix to both be null.

        // We still need to add that matcher for strict mode to work.

        fAffixMatchers[numAffixMatchers++] = {prefix, suffix, flags};

        if (includeUnpaired && prefix != nullptr && suffix != nullptr) {

            // The following if statements are designed to prevent adding two identical matchers.

            if (type == PATTERN_SIGN_TYPE_POS || !equals(prefix, posPrefix)) {

                fAffixMatchers[numAffixMatchers++] = {prefix, nullptr, flags};

            }

            if (type == PATTERN_SIGN_TYPE_POS || !equals(suffix, posSuffix)) {

                fAffixMatchers[numAffixMatchers++] = {nullptr, suffix, flags};

            }

        }

    }

    // Put the AffixMatchers in order, and then add them to the output.

    // Since there are at most 9 elements, do a simple-to-implement bubble sort.

    bool madeChanges;

    do {

        madeChanges = false;

        for (int32_t i = 1; i < numAffixMatchers; i++) {

            if (fAffixMatchers[i - 1].compareTo(fAffixMatchers[i]) > 0) {

                madeChanges = true;

                AffixMatcher temp = std::move(fAffixMatchers[i - 1]);

                fAffixMatchers[i - 1] = std::move(fAffixMatchers[i]);

                fAffixMatchers[i] = std::move(temp);

            }

        }

    } while (madeChanges);

    for (int32_t i = 0; i < numAffixMatchers; i++) {

        // Enable the following line to debug affixes

        //std::cout << "Adding affix matcher: " << CStr(fAffixMatchers[i].toString())() << std::endl;

        output.addMatcher(fAffixMatchers[i]);

    }

}

AffixMatcher::AffixMatcher(AffixPatternMatcher* prefix, AffixPatternMatcher* suffix, result_flags_t flags)

        : fPrefix(prefix), fSuffix(suffix), fFlags(flags) {}

bool AffixMatcher::match(StringSegment& segment, ParsedNumber& result, UErrorCode& status) const {

    if (!result.seenNumber()) {

        // Prefix

        // Do not match if:

        // 1. We have already seen a prefix (result.prefix != null)

        // 2. The prefix in this AffixMatcher is empty (prefix == null)

        if (!result.prefix.isBogus() || fPrefix == nullptr) {

            return false;

        }

        // Attempt to match the prefix.

        int initialOffset = segment.getOffset();

        bool maybeMore = fPrefix->match(segment, result, status);

        if (initialOffset != segment.getOffset()) {

            result.prefix = fPrefix->getPattern();

        }

        return maybeMore;

    } else {

        // Suffix

        // Do not match if:

        // 1. We have already seen a suffix (result.suffix != null)

        // 2. The suffix in this AffixMatcher is empty (suffix == null)

        // 3. The matched prefix does not equal this AffixMatcher's prefix

        if (!result.suffix.isBogus() || fSuffix == nullptr || !matched(fPrefix, result.prefix)) {

            return false;

        }

        // Attempt to match the suffix.

        int initialOffset = segment.getOffset();

        bool maybeMore = fSuffix->match(segment, result, status);

        if (initialOffset != segment.getOffset()) {

            result.suffix = fSuffix->getPattern();

        }

        return maybeMore;

    }

}

bool AffixMatcher::smokeTest(const StringSegment& segment) const {

    return (fPrefix != nullptr && fPrefix->smokeTest(segment)) ||

           (fSuffix != nullptr && fSuffix->smokeTest(segment));

}

void AffixMatcher::postProcess(ParsedNumber& result) const {

    // Check to see if our affix is the one that was matched. If so, set the flags in the result.

    if (matched(fPrefix, result.prefix) && matched(fSuffix, result.suffix)) {

        // Fill in the result prefix and suffix with non-null values (empty string).

        // Used by strict mode to determine whether an entire affix pair was matched.

        if (result.prefix.isBogus()) {

            result.prefix = UnicodeString();

        }

        if (result.suffix.isBogus()) {

            result.suffix = UnicodeString();

        }

        result.flags |= fFlags;

        if (fPrefix != nullptr) {

            fPrefix->postProcess(result);

        }

        if (fSuffix != nullptr) {

            fSuffix->postProcess(result);

        }

    }

}

int8_t AffixMatcher::compareTo(const AffixMatcher& rhs) const {

    const AffixMatcher& lhs = *this;

    if (length(lhs.fPrefix) != length(rhs.fPrefix)) {

        return length(lhs.fPrefix) > length(rhs.fPrefix) ? -1 : 1;

    } else if (length(lhs.fSuffix) != length(rhs.fSuffix)) {

        return length(lhs.fSuffix) > length(rhs.fSuffix) ? -1 : 1;

    } else {

        return 0;

    }

}

UnicodeString AffixMatcher::toString() const {

    bool isNegative = 0 != (fFlags & FLAG_NEGATIVE);

    return UnicodeString(u"<Affix") + (isNegative ? u":negative " : u" ") +

           (fPrefix ? fPrefix->getPattern() : u"null") + u"#" +

           (fSuffix ? fSuffix->getPattern() : u"null") + u">";

}

#endif /* #if !UCONFIG_NO_FORMATTING */