package org.unicode.cldr.test;

import java.util.BitSet;
import java.util.List;

import org.unicode.cldr.test.CheckCLDR.CheckStatus.Subtype;
import org.unicode.cldr.util.CLDRConfig;
import org.unicode.cldr.util.CLDRFile;
import org.unicode.cldr.util.Factory;
import org.unicode.cldr.util.SupplementalDataInfo;
import org.unicode.cldr.util.UnicodeSetPrettyPrinter;
import org.unicode.cldr.util.XPathParts;

import com.ibm.icu.lang.UCharacter;
import com.ibm.icu.lang.UCharacterDirection;
import com.ibm.icu.lang.UProperty;
import com.ibm.icu.lang.UScript;
import com.ibm.icu.text.Collator;
import com.ibm.icu.text.UnicodeSet;
import com.ibm.icu.text.UnicodeSetIterator;
import com.ibm.icu.util.ULocale;

public class CheckExemplars extends FactoryCheckCLDR {

    public static final boolean USE_PUNCTUATION = false;
    private static final boolean SUPPRESS_AUX_EMPTY_CHECK = true;
    private static final String[] QUOTE_ELEMENTS = {
        "quotationStart", "quotationEnd",
        "alternateQuotationStart", "alternateQuotationEnd" };
    static final SupplementalDataInfo SUP = CLDRConfig.getInstance().getSupplementalDataInfo();

    Collator col;
    Collator spaceCol;
    boolean isRoot;
    UnicodeSetPrettyPrinter prettyPrinter;

    static final UnicodeSet HangulSyllables = new UnicodeSet(
        "[[:Hangul_Syllable_Type=LVT:][:Hangul_Syllable_Type=LV:]]").freeze();

    public static final UnicodeSet AlwaysOK;
    static {
        if (USE_PUNCTUATION) {
            AlwaysOK = new UnicodeSet("[\\u0020\\u00A0]");
        } else {
            AlwaysOK = new UnicodeSet(
                "[[[:Nd:][:script=common:][:script=inherited:]-[:Default_Ignorable_Code_Point:]-[:C:] - [_]] [\u05BE \u05F3 \u066A-\u066C]" +
                    "[[؉][་ །༌][ཱ]‎‎{য়}য়]" + // TODO Fix this Hack
                "]"); // [\\u200c-\\u200f] [:script=common:][:script=inherited:]
        }
        AlwaysOK.freeze();
    }
    // TODO Fix some of these characters
    private static final UnicodeSet SPECIAL_ALLOW = new UnicodeSet(
        "[\\u200E\\u200F\\u200c\\u200d"
            +
            "‎‎‎[\u064B\u064E-\u0651\u0670]‎[:Nd:]‎[\u0951\u0952]‎[\u064B-\u0652\u0654-\u0657\u0670]‎[\u0A66-\u0A6F][\u0ED0-\u0ED9][\u064B-\u0652]‎[\\u02BB\\u02BC][\u0CE6-\u0CEF]‎‎[\u0966-\u096F]"
            +
            "‎‎‎[:word_break=Katakana:][:word_break=ALetter:][:word_break=MidLetter:] ]" // restore
            // [:word_break=Katakana:][:word_break=ALetter:][:word_break=MidLetter:]
        ).freeze(); // add RLM, LRM [\u200C\u200D]‎

    public static final UnicodeSet UAllowedInExemplars = new UnicodeSet("[[:assigned:]-[:Z:]]") // [:alphabetic:][:Mn:][:word_break=Katakana:][:word_break=ALetter:][:word_break=MidLetter:]
    .removeAll(AlwaysOK) // this will remove some
    // [:word_break=Katakana:][:word_break=ALetter:][:word_break=MidLetter:] so we restore them
    // in SPECIAL_ALLOW
    .addAll(SPECIAL_ALLOW) // add RLM, LRM [\u200C\u200D]‎
    .freeze();

    public static final UnicodeSet AllowedInExemplars = new UnicodeSet(UAllowedInExemplars)
    .removeAll(new UnicodeSet("[[:Uppercase:]-[\u0130]]"))
    .freeze();

    public static final UnicodeSet ALLOWED_IN_PUNCTUATION = new UnicodeSet("[[:P:][:S:]]")
    .freeze();

    public static final UnicodeSet ALLOWED_IN_AUX = new UnicodeSet(AllowedInExemplars)
    .addAll(ALLOWED_IN_PUNCTUATION)
    .removeAll(AlwaysOK) // this will remove some
    // [:word_break=Katakana:][:word_break=ALetter:][:word_break=MidLetter:] so we restore them
    // in SPECIAL_ALLOW
    .addAll(SPECIAL_ALLOW) // add RLM, LRM [\u200C\u200D]‎
    .freeze();

    public enum ExemplarType {
        main(AllowedInExemplars, "(specific-script - uppercase - invisibles + \u0130)", true),
        punctuation(ALLOWED_IN_PUNCTUATION, "punctuation", false),
        auxiliary(ALLOWED_IN_AUX, "(specific-script - uppercase - invisibles + \u0130)", true),
        index(UAllowedInExemplars, "(specific-script - invisibles)", false),
        currencySymbol(AllowedInExemplars, "(specific-script - uppercase - invisibles + \u0130)", false);

        public final UnicodeSet allowed;
        public final UnicodeSet toRemove;
        public final String message;
        public final boolean convertUppercase;

        ExemplarType(UnicodeSet allowed, String message, boolean convertUppercase) {
            if (!allowed.isFrozen()) {
                throw new IllegalArgumentException("Internal Error");
            }
            this.allowed = allowed;
            this.message = message;
            this.toRemove = new UnicodeSet(allowed).complement().freeze();
            this.convertUppercase = convertUppercase;
        }
    }

    public CheckExemplars(Factory factory) {
        super(factory);
    }

    // Allowed[:script=common:][:script=inherited:][:alphabetic=false:]

    @Override
    public CheckCLDR setCldrFileToCheck(CLDRFile cldrFileToCheck, Options options,
        List<CheckStatus> possibleErrors) {
        if (cldrFileToCheck == null) return this;
        super.setCldrFileToCheck(cldrFileToCheck, options, possibleErrors);
        String locale = cldrFileToCheck.getLocaleID();
        col = Collator.getInstance(new ULocale(locale));
        spaceCol = Collator.getInstance(new ULocale(locale));
        spaceCol.setStrength(Collator.PRIMARY);
        isRoot = cldrFileToCheck.getLocaleID().equals("root");
        prettyPrinter = new UnicodeSetPrettyPrinter()
        .setOrdering(col != null ? col : Collator.getInstance(ULocale.ROOT))
        .setSpaceComparator(col != null ? col : Collator.getInstance(ULocale.ROOT)
            .setStrength2(Collator.PRIMARY))
            .setCompressRanges(true);

        // check for auxiliary anyway
        if (!SUPPRESS_AUX_EMPTY_CHECK) {
            UnicodeSet auxiliarySet = getResolvedCldrFileToCheck().getExemplarSet("auxiliary",
                CLDRFile.WinningChoice.WINNING);

            if (auxiliarySet == null) {
                possibleErrors.add(
                    new CheckStatus().setCause(this)
                    .setMainType(CheckStatus.warningType)
                    .setSubtype(Subtype.missingAuxiliaryExemplars)
                    .setMessage("Most languages allow <i>some<i> auxiliary characters, so review this."));
            }
        }
        return this;
    }

    public CheckCLDR handleCheck(String path, String fullPath, String value, Options options,
        List<CheckStatus> result) {
        if (fullPath == null) return this; // skip paths that we don't have
        if (path.indexOf("/exemplarCharacters") < 0) {
            if (path.contains("parseLenient")) {
                checkParse(path, fullPath, value, options, result);
            }
            return this;
        }
        XPathParts oparts = XPathParts.getFrozenInstance(path);
        final String exemplarString = oparts.findAttributeValue("exemplarCharacters", "type");
        ExemplarType type = exemplarString == null ? ExemplarType.main : ExemplarType.valueOf(exemplarString);
        checkExemplar(value, result, type);

        // check relation to auxiliary set
        try {
            UnicodeSet mainSet = getResolvedCldrFileToCheck().getExemplarSet("", CLDRFile.WinningChoice.WINNING);
            if (type == ExemplarType.auxiliary) {
                UnicodeSet auxiliarySet = new UnicodeSet(value);

                UnicodeSet combined = new UnicodeSet(mainSet).addAll(auxiliarySet);
                checkMixedScripts("main+auxiliary", combined, result);

                if (auxiliarySet.containsSome(mainSet)) {
                    UnicodeSet overlap = new UnicodeSet(mainSet).retainAll(auxiliarySet).removeAll(HangulSyllables);
                    if (overlap.size() != 0) {
                        String fixedExemplar1 = new UnicodeSetPrettyPrinter()
                        .setOrdering(col != null ? col : Collator.getInstance(ULocale.ROOT))
                        .setSpaceComparator(col != null ? col : Collator.getInstance(ULocale.ROOT)
                            .setStrength2(Collator.PRIMARY))
                            .setCompressRanges(true)
                            .format(overlap);
                        result
                        .add(new CheckStatus()
                        .setCause(this)
                        .setMainType(CheckStatus.errorType)
                        .setSubtype(Subtype.auxiliaryExemplarsOverlap)
                        .setMessage("Auxiliary characters also exist in main: \u200E{0}\u200E",
                            new Object[] { fixedExemplar1 }));
                    }
                }
            } else if (type == ExemplarType.punctuation) {
                // Check that the punctuation exemplar characters include quotation marks.
                UnicodeSet punctuationSet = new UnicodeSet(value);
                UnicodeSet quoteSet = new UnicodeSet();
                for (String element : QUOTE_ELEMENTS) {
                    quoteSet.add(getResolvedCldrFileToCheck().getWinningValue("//ldml/delimiters/" + element));
                }
                if (!punctuationSet.containsAll(quoteSet)) {
                    quoteSet.removeAll(punctuationSet);
                    // go ahead and list the characters separately, with space between, for clarity.
                    StringBuilder characters = new StringBuilder();
                    for (String item : quoteSet) {
                        if (characters.length() != 0) {
                            characters.append(" ");
                        }
                        characters.append(item);
                    }
                    // String characters = quoteSet.toPattern(false);
                    CheckStatus message = new CheckStatus().setCause(this)
                        .setMainType(CheckStatus.warningType)
                        .setSubtype(Subtype.missingPunctuationCharacters)
                        .setMessage("Punctuation exemplar characters are missing quotation marks for this locale: {0}",
                            characters);
                    result.add(message);
                }
            } else if (type == ExemplarType.index) {
                // Check that the index exemplar characters are in case-completed union of main and auxiliary exemplars
                UnicodeSet auxiliarySet = getResolvedCldrFileToCheck().getExemplarSet("auxiliary", CLDRFile.WinningChoice.WINNING);
                if (auxiliarySet == null) {
                    auxiliarySet = new UnicodeSet();
                }
                UnicodeSet mainAndAuxAllCase = new UnicodeSet(mainSet).addAll(auxiliarySet).closeOver(UnicodeSet.ADD_CASE_MAPPINGS);
                UnicodeSet indexBadChars = new UnicodeSet(value).removeAll(mainAndAuxAllCase);

                if (!indexBadChars.isEmpty()) {
                    CheckStatus message = new CheckStatus().setCause(this)
                        .setMainType(CheckStatus.warningType)
                        .setSubtype(Subtype.charactersNotInMainOrAuxiliaryExemplars)
                        .setMessage("Index exemplars include characters not in main or auxiliary exemplars: {0}",
                            indexBadChars.toPattern(false));
                    result.add(message);
                }
            }

            // check for consistency with RTL

            Boolean localeIsRTL = false;
            String charOrientation = getResolvedCldrFileToCheck().getStringValue(
                "//ldml/layout/orientation/characterOrder");
            if (charOrientation.equals("right-to-left")) {
                localeIsRTL = true;
            }

            UnicodeSetIterator mi = new UnicodeSetIterator(mainSet);
            while (mi.next()) {
                if (mi.codepoint != UnicodeSetIterator.IS_STRING &&
                    (UCharacter.getDirection(mi.codepoint) == UCharacterDirection.RIGHT_TO_LEFT ||
                    UCharacter.getDirection(mi.codepoint) == UCharacterDirection.RIGHT_TO_LEFT_ARABIC) &&
                    !localeIsRTL) {
                    result.add(new CheckStatus()
                    .setCause(this)
                    .setMainType(CheckStatus.errorType)
                    .setSubtype(Subtype.orientationDisagreesWithExemplars)
                    .setMessage(
                        "Main exemplar set contains RTL characters, but orientation of this locale is not RTL."));
                    break;
                }
            }

        } catch (Exception e) {
        } // if these didn't parse, checkExemplar will be called anyway at some point
        return this;
    }

    private void checkParse(String path, String fullPath, String value, Options options, List<CheckStatus> result) {
        try {
            XPathParts oparts = XPathParts.getFrozenInstance(path);
            // only thing we do is make sure that the sample is in the value
            UnicodeSet us = new UnicodeSet(value);
            String sampleValue = oparts.getAttributeValue(-1, "sample");
            if (!us.contains(sampleValue)) {
                CheckStatus message = new CheckStatus().setCause(this)
                    .setMainType(CheckStatus.errorType)
                    .setSubtype(Subtype.badParseLenient)
                    .setMessage("ParseLenient sample not in value: {0} ∌ {1}", us, sampleValue);
                result.add(message);            
            }
        } catch (Exception e) {
            CheckStatus message = new CheckStatus().setCause(this)
                .setMainType(CheckStatus.errorType)
                .setSubtype(Subtype.badParseLenient)
                .setMessage(e.getMessage());
            result.add(message);            
        }
    }

    static final BitSet Japn = new BitSet();
    static final BitSet Kore = new BitSet();
    static {
        Japn.set(UScript.HAN);
        Japn.set(UScript.HIRAGANA);
        Japn.set(UScript.KATAKANA);
        Kore.set(UScript.HAN);
        Kore.set(UScript.HANGUL);
    }

    private void checkMixedScripts(String title, UnicodeSet set, List<CheckStatus> result) {
        BitSet s = new BitSet();
        for (String item : set) {
            int script = UScript.getScript(item.codePointAt(0));
            if (script != UScript.COMMON && script != UScript.INHERITED) {
                s.set(script);
            }
        }
        final int cardinality = s.cardinality();
        if (cardinality < 2) {
            return;
        }
        if (cardinality == 2 && title.equals("currencySymbol") && s.get(UScript.LATIN)) {
            return; // allow 2 scripts in exemplars for currencies.
        }
        // allowable combinations
        if (s.equals(Japn) || s.equals(Kore)) {
            return;
        }
        StringBuilder scripts = new StringBuilder();
        for (int i = s.nextSetBit(0); i >= 0; i = s.nextSetBit(i + 1)) {
            if (scripts.length() != 0) {
                scripts.append(", ");
            }
            scripts.append(UScript.getName(i));
            UnicodeSet inSet = new UnicodeSet().applyIntPropertyValue(UProperty.SCRIPT, i).retainAll(set);
            int count = 0;
            scripts.append(" (");
            for (String cp : inSet) {
                if (count != 0) {
                    scripts.append(",");
                }
                scripts.append(cp);
                count++;
                if (count > 3) {
                    scripts.append('\u2026');
                    break;
                }
            }
            scripts.append(")");
        }
        result.add(new CheckStatus().setCause(this).setMainType(CheckStatus.errorType)
            .setSubtype(Subtype.illegalExemplarSet)
            .setMessage("{0} exemplars contain multiple scripts: {1}", new Object[] { title, scripts }));
        return;
    }

    private void checkExemplar(String v, List<CheckStatus> result, ExemplarType exemplarType) {
        if (v == null) return;
        final UnicodeSet exemplar1;
        try {
            exemplar1 = new UnicodeSet(v).freeze();
        } catch (Exception e) {
            result.add(new CheckStatus().setCause(this).setMainType(CheckStatus.errorType)
                .setSubtype(Subtype.illegalExemplarSet)
                .setMessage("This field must be a set of the form [a b c-d ...]: ", new Object[] { e.getMessage() }));
            return;
        }

        // check for mixed scripts

        checkMixedScripts(exemplarType.toString(), exemplar1, result);

        // check that the formatting is correct

        String fixedExemplar1 = prettyPrinter.format(exemplar1);
        UnicodeSet doubleCheck = new UnicodeSet(fixedExemplar1);
        if (!doubleCheck.equals(exemplar1)) {
            result.add(new CheckStatus().setCause(this).setMainType(CheckStatus.errorType)
                .setSubtype(Subtype.internalUnicodeSetFormattingError)
                .setMessage("Internal Error: formatting not working for {0}", new Object[] { exemplar1 }));
        }
        // else if (!v.equals(fixedExemplar1)) {
        // result.add(new CheckStatus().setCause(this).setType(CheckStatus.warningType)
        // .setMessage("Better formatting would be \u200E{0}\u200E", new Object[]{fixedExemplar1}));
        // }

        // now check that only allowed characters are in the set

        if (!exemplarType.allowed.containsAll(exemplar1)) {
            UnicodeSet remainder0 = new UnicodeSet(exemplar1).removeAll(exemplarType.allowed);

            // we do allow for punctuation & combining marks in strings
            UnicodeSet remainder = new UnicodeSet();
            for (String s : remainder0) {
                if (Character.codePointCount(s, 0, s.length()) == 1) {
                    remainder.add(s);
                } else {
                    // just check normalization
                }
            }

            // after a first check, we check again in case we flattened

            if (remainder.size() != 0) {
                fixedExemplar1 = prettyPrinter.format(exemplar1);
                result.add(new CheckStatus().setCause(this).setMainType(CheckStatus.warningType)
                    .setSubtype(Subtype.illegalCharactersInExemplars)
                    .setMessage("Should be limited to " + exemplarType.message + "; thus not contain: \u200E{0}\u200E",
                        new Object[] { remainder }));
            }
        }

        // now check for empty

        if (!isRoot && exemplar1.size() == 0) {
            switch (exemplarType) {
            case currencySymbol: // ok if empty
                break;
            case auxiliary:
                result.add(new CheckStatus().setCause(this).setMainType(CheckStatus.warningType)
                    .setSubtype(Subtype.missingAuxiliaryExemplars)
                    .setMessage("Most languages allow <i>some<i> auxiliary characters, so review this."));
                break;
            case index:
            case punctuation:
            case main:
                result.add(new CheckStatus()
                .setCause(this)
                .setMainType(CheckStatus.errorType)
                .setSubtype(Subtype.missingMainExemplars)
                .setMessage(
                    "Exemplar set (" + exemplarType
                    + ") must not be empty -- that would imply that this language uses no " +
                    (exemplarType == ExemplarType.punctuation ? "punctuation" : "letters") + "!"));
                break;
            }
        }
    }
}
