// Copyright 2012 Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.hughes.android.dictionary.parser.wiktionary;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;

import com.hughes.android.dictionary.engine.EntryTypeName;
import com.hughes.android.dictionary.engine.IndexBuilder;
import com.hughes.android.dictionary.engine.IndexedEntry;
import com.hughes.android.dictionary.engine.PairEntry;
import com.hughes.android.dictionary.parser.WikiTokenizer;

public final class EnForeignParser extends EnParser {

    public EnForeignParser(final IndexBuilder enIndexBuilder,
                           final IndexBuilder otherIndexBuilder, final Pattern langPattern,
                           final Pattern langCodePattern, final boolean swap) {
        super(enIndexBuilder, otherIndexBuilder, langPattern, langCodePattern, swap);
    }

    @Override
    void parseSection(String heading, String text) {
        if (isIgnorableTitle(title)) {
            return;
        }
        final String lang = heading.replace("=", "").trim();
        if (!langPattern.matcher(lang).find()) {
            return;
        }

        final WikiTokenizer wikiTokenizer = new WikiTokenizer(text);
        while (wikiTokenizer.nextToken() != null) {
            if (wikiTokenizer.isHeading()) {
                final String headingName = wikiTokenizer.headingWikiText();
                if (headingName.equals("Translations")) {
                    LOG.warning("Translations not in English section: " + title);
                    incrementCount("WARNING: Translations not in English section");
                } else if (headingName.equals("Pronunciation")) {
                    //doPronunciation(wikiLineReader);
                } else if (headingName.startsWith(" {{S|")) {
                    // HACK to support parsing frwiktionary
                    String[] parts = headingName.split("\\|");
                    if (parts.length > 2 && langCodePattern.matcher(parts[2]).find() &&
                            (parts.length < 4 || !parts[3].startsWith("flexion"))) {
                        doForeignPartOfSpeech(lang, headingName, wikiTokenizer.headingDepth(), wikiTokenizer);
                    }
                } else if (partOfSpeechHeader.matcher(headingName).matches()) {
                    doForeignPartOfSpeech(lang, headingName, wikiTokenizer.headingDepth(), wikiTokenizer);
                }
            } else {
                // It's not a heading.
                // TODO: optimization: skip to next heading.
            }
        }
    }

    static final class ListSection {
        final String firstPrefix;
        final String firstLine;
        final List<String> nextPrefixes = new ArrayList<>();
        final List<String> nextLines = new ArrayList<>();

        public ListSection(String firstPrefix, String firstLine) {
            this.firstPrefix = firstPrefix;
            this.firstLine = firstLine;
        }

        @Override
        public String toString() {
            return firstPrefix + firstLine + "{ " + nextPrefixes + "}";
        }
    }

    int foreignCount = 0;
    private void doForeignPartOfSpeech(final String lang, String posHeading, final int posDepth, WikiTokenizer wikiTokenizer) {
        if (++foreignCount % 1000 == 0) {
            LOG.info("***" + lang + ", " + title + ", pos=" + posHeading + ", foreignCount=" + foreignCount);
        }
        if (title.equals("6")) {
            System.out.println();
        }

        final StringBuilder foreignBuilder = new StringBuilder();
        final List<EnForeignParser.ListSection> listSections = new ArrayList<>();

        appendAndIndexWikiCallback.reset(foreignBuilder, null);
        this.state = State.ENGLISH_DEF_OF_FOREIGN;  // TODO: this is wrong, need new category....
        titleAppended = false;
        wordForms.clear();

        try {

            EnForeignParser.ListSection lastListSection = null;

            int currentHeadingDepth = posDepth;
            while (wikiTokenizer.nextToken() != null) {
                if (wikiTokenizer.isHeading()) {
                    currentHeadingDepth = wikiTokenizer.headingDepth();

                    if (currentHeadingDepth <= posDepth) {
                        wikiTokenizer.returnToLineStart();
                        return;
                    }
                }  // heading

                if (currentHeadingDepth > posDepth) {
                    // TODO: deal with other neat info sections inside POS
                    continue;
                }

                if (wikiTokenizer.isFunction()) {
                    final String name = wikiTokenizer.functionName();
                    final List<String> args = wikiTokenizer.functionPositionArgs();
                    final Map<String,String> namedArgs = wikiTokenizer.functionNamedArgs();
                    // First line is generally a repeat of the title with some extra information.
                    // We need to build up the left side (foreign text, tokens) separately from the
                    // right side (English).  The left-side may get paired with multiple right sides.
                    // The left side should get filed under every form of the word in question (singular, plural).

                    // For verbs, the conjugation comes later on in a deeper section.
                    // Ideally, we'd want to file every English entry with the verb
                    // under every verb form coming from the conjugation.
                    // Ie. under "fa": see: "make :: fare" and "do :: fare"
                    // But then where should we put the conjugation table?
                    // I think just under fare.  But then we need a way to link to the entry (actually the row, since entries doesn't show up!)
                    // for the conjugation table from "fa".
                    // Would like to be able to link to a lang#token.


                    String head = namedArgs.remove("head");
                    final String tr = namedArgs.remove("tr");
                    if (head == null && tr != null && !titleAppended) {
                        head = title;
                    }
                    if (head != null) {
                        final String form = appendAndIndexWikiCallback.dispatch(head, EntryTypeName.WIKTIONARY_TITLE_MULTI);
                        wordForms.add(form);
                        appendAndIndexWikiCallback.builder.append(" ");
                        titleAppended = true;
                    }
                    if (tr != null) {
                        appendAndIndexWikiCallback.builder.append(" (");
                        final String form = appendAndIndexWikiCallback.dispatch(tr, EntryTypeName.WIKTIONARY_TRANSLITERATION);
                        wordForms.add(form);
                        appendAndIndexWikiCallback.builder.append(") ");
                    }

                    appendAndIndexWikiCallback.onFunction(wikiTokenizer, name, args, namedArgs);

                } else if (wikiTokenizer.isListItem()) {
                    final String prefix = wikiTokenizer.listItemPrefix();
                    if (lastListSection != null &&
                            prefix.startsWith(lastListSection.firstPrefix) &&
                            prefix.length() > lastListSection.firstPrefix.length()) {
                        lastListSection.nextPrefixes.add(prefix);
                        lastListSection.nextLines.add(wikiTokenizer.listItemWikiText());
                    } else {
                        lastListSection = new ListSection(prefix, wikiTokenizer.listItemWikiText());
                        listSections.add(lastListSection);
                    }
                } else if (lastListSection != null) {
                    // Don't append anything after the lists, because there's crap.
                } else if (wikiTokenizer.isWikiLink()) {
                    // Unindexed!
                    foreignBuilder.append(wikiTokenizer.wikiLinkText());

                } else if (wikiTokenizer.isPlainText()) {
                    // Unindexed!
                    foreignBuilder.append(wikiTokenizer.token());
                } else if (wikiTokenizer.isHtml()) {
                    if (!wikiTokenizer.token().startsWith("<ref>")) {
                        foreignBuilder.append(wikiTokenizer.token());
                    }
                } else if (wikiTokenizer.isMarkup() ||
                           wikiTokenizer.isNewline() ||
                           wikiTokenizer.isComment()) {
                    // Do nothing.
                } else {
                    LOG.warning("Unexpected token: " + wikiTokenizer.token());
                    assert !wikiTokenizer.errors().isEmpty();
                }
            }

        } finally {
            // Here's where we exit.
            // Should we make an entry even if there are no foreign list items?
            String foreign = foreignBuilder.toString().trim();
            if (!titleAppended && !foreign.toLowerCase().startsWith(title.toLowerCase())) {
                foreign = String.format("%s %s", title, foreign);
            }
            if (!langPattern.matcher(lang).matches()) {
                foreign = String.format("(%s) %s", lang, foreign);
            }
            for (final EnForeignParser.ListSection listSection : listSections) {
                doForeignListSection(foreign, title, wordForms, listSection);
            }
        }
    }

    private void doForeignListSection(final String foreignText, String title, final Collection<String> forms, final EnForeignParser.ListSection listSection) {
        state = State.ENGLISH_DEF_OF_FOREIGN;
        final String prefix = listSection.firstPrefix;
        if (prefix.length() > 1) {
            // Could just get looser and say that any prefix longer than first is a sublist.
            LOG.warning("Prefix '" + prefix + "' too long: " + listSection);
            incrementCount("WARNING: Prefix too long");
            return;
        }

        final PairEntry pairEntry = new PairEntry(entrySource);
        final IndexedEntry indexedEntry = new IndexedEntry(pairEntry);
        indexedEntry.isValid = true;

        entryIsFormOfSomething = false;
        final StringBuilder englishBuilder = new StringBuilder();
        final String mainLine = listSection.firstLine;
        appendAndIndexWikiCallback.reset(englishBuilder, indexedEntry);
        appendAndIndexWikiCallback.dispatch(mainLine, enIndexBuilder, EntryTypeName.WIKTIONARY_ENGLISH_DEF);

        final String english = trim(englishBuilder.toString());
        if (english.length() > 0) {
            final PairEntry.Pair pair = new PairEntry.Pair(english, trim(foreignText), this.swap);
            pairEntry.pairs.add(pair);
            foreignIndexBuilder.addEntryWithString(indexedEntry, title, entryIsFormOfSomething ? EntryTypeName.WIKTIONARY_IS_FORM_OF_SOMETHING_ELSE : EntryTypeName.WIKTIONARY_TITLE_MULTI);
            for (final String form : forms) {
                foreignIndexBuilder.addEntryWithString(indexedEntry, form, EntryTypeName.WIKTIONARY_INFLECTED_FORM_MULTI);
            }
        }

        // Do examples.
        String lastForeign = null;
        for (int i = 0; i < listSection.nextPrefixes.size(); ++i) {
            final String nextPrefix = listSection.nextPrefixes.get(i);
            String nextLine = listSection.nextLines.get(i);

            // TODO: This splitting is not sensitive to wiki code.
            int dash = nextLine.indexOf("&mdash;");
            int mdashLen = 7;
            if (dash == -1) {
                dash = nextLine.indexOf("—");
                mdashLen = 1;
            }
            if (dash == -1) {
                dash = nextLine.indexOf(" - ");
                mdashLen = 3;
            }

            if ((nextPrefix.equals("#:") || nextPrefix.equals("##:")) && dash != -1) {
                final String foreignEx = nextLine.substring(0, dash);
                final String englishEx = nextLine.substring(dash + mdashLen);
                final PairEntry.Pair pair = new PairEntry.Pair(formatAndIndexExampleString(englishEx, enIndexBuilder, indexedEntry), formatAndIndexExampleString(foreignEx, foreignIndexBuilder, indexedEntry), swap);
                if (pair.lang1 != "--" && pair.lang1 != "--") {
                    pairEntry.pairs.add(pair);
                }
                lastForeign = null;
                // TODO: make #* and #*: work
            } else if (nextPrefix.equals("#:") || nextPrefix.equals("##:")/* || nextPrefix.equals("#*")*/) {
                final PairEntry.Pair pair = new PairEntry.Pair("--", formatAndIndexExampleString(nextLine, null, indexedEntry), swap);
                lastForeign = nextLine;
                if (pair.lang1 != "--" && pair.lang1 != "--") {
                    pairEntry.pairs.add(pair);
                }
            } else if (nextPrefix.equals("#::") || nextPrefix.equals("#**")/* || nextPrefix.equals("#*:")*/) {
                if (lastForeign != null && pairEntry.pairs.size() > 0) {
                    if (i + 1 < listSection.nextPrefixes.size()) {
                        // Chinese has sometimes multiple foreign lines
                        final String nextNextPrefix = listSection.nextPrefixes.get(i + 1);
                        if (nextNextPrefix.equals("#::") || nextNextPrefix.equals("#**")) {
                            ++i;
                            nextLine += "\n" + listSection.nextLines.get(i);
                        }
                    }
                    pairEntry.pairs.remove(pairEntry.pairs.size() - 1);
                    final PairEntry.Pair pair = new PairEntry.Pair(formatAndIndexExampleString(nextLine, enIndexBuilder, indexedEntry), formatAndIndexExampleString(lastForeign, foreignIndexBuilder, indexedEntry), swap);
                    if (pair.lang1 != "--" || pair.lang2 != "--") {
                        pairEntry.pairs.add(pair);
                    }
                    lastForeign = null;
                } else {
                    LOG.warning("TODO: English example with no foreign: " + title + ", " + nextLine);
                    final PairEntry.Pair pair = new PairEntry.Pair("--", formatAndIndexExampleString(nextLine, null, indexedEntry), swap);
                    if (pair.lang1 != "--" || pair.lang2 != "--") {
                        pairEntry.pairs.add(pair);
                    }
                }
            } else if (nextPrefix.equals("#*")) {
                // Can't really index these.
                final PairEntry.Pair pair = new PairEntry.Pair("--", formatAndIndexExampleString(nextLine, null, indexedEntry), swap);
                lastForeign = nextLine;
                if (pair.lang1 != "--" || pair.lang2 != "--") {
                    pairEntry.pairs.add(pair);
                }
            } else if (nextPrefix.equals("#::*") || nextPrefix.equals("##") || nextPrefix.equals("#*:") || nextPrefix.equals("#:*") || true) {
                final PairEntry.Pair pair = new PairEntry.Pair("--", formatAndIndexExampleString(nextLine, null, indexedEntry), swap);
                if (pair.lang1 != "--" || pair.lang2 != "--") {
                    pairEntry.pairs.add(pair);
                }
//        } else {
//          assert false;
            }
        }
    }

    private String formatAndIndexExampleString(final String example, final IndexBuilder indexBuilder, final IndexedEntry indexedEntry) {
        // TODO:
//      if (wikiTokenizer.token().equals("'''")) {
//        insideTripleQuotes = !insideTripleQuotes;
//      }
        final StringBuilder builder = new StringBuilder();
        appendAndIndexWikiCallback.reset(builder, indexedEntry);
        appendAndIndexWikiCallback.entryTypeName = EntryTypeName.WIKTIONARY_EXAMPLE;
        appendAndIndexWikiCallback.entryTypeNameSticks = true;
        try {
            // TODO: this is a hack needed because we don't safely split on the dash.
            appendAndIndexWikiCallback.dispatch(example, indexBuilder, EntryTypeName.WIKTIONARY_EXAMPLE);
        } catch (AssertionError e) {
            return "--";
        }
        final String result = trim(builder.toString());
        return result.length() > 0 ? result : "--";
    }


}  // ForeignParser