package com.hughes.android.dictionary.engine;

import com.hughes.util.StringUtil;
import com.hughes.util.raf.RAFListSerializer;
import com.hughes.util.raf.RAFSerializable;
import com.ibm.icu.text.Transliterator;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.PrintStream;
import java.io.RandomAccessFile;
import java.lang.ref.SoftReference;
import java.util.List;
import java.util.regex.Pattern;

public class HtmlEntry extends AbstractEntry implements RAFSerializable<HtmlEntry>,
        Comparable<HtmlEntry> {

    // Title is not HTML escaped.
    public final String title;
    public final LazyHtmlLoader lazyHtmlLoader;
    public String html;

    public HtmlEntry(final EntrySource entrySource, String title) {
        super(entrySource);
        this.title = title;
        lazyHtmlLoader = null;
    }

    public HtmlEntry(Dictionary dictionary, DataInput raf, final int index)
            throws IOException {
        super(dictionary, raf, index);
        title = raf.readUTF();
        lazyHtmlLoader = new LazyHtmlLoader(raf);
        html = null;
    }

    @Override
    public void write(DataOutput raf) throws IOException {
        super.write(raf);
        raf.writeUTF(title);

        final byte[] bytes = getHtml().getBytes("UTF-8");
        final byte[] zipBytes = StringUtil.zipBytes(bytes);
        raf.writeInt(bytes.length);
        raf.writeInt(zipBytes.length);
        raf.write(zipBytes);
    }

    String getHtml() {
        return html != null ? html : lazyHtmlLoader.getHtml();
    }

    @Override
    public void addToDictionary(Dictionary dictionary) {
        assert index == -1;
        dictionary.htmlEntries.add(this);
        index = dictionary.htmlEntries.size() - 1;
    }

    @Override
    public RowBase CreateRow(int rowIndex, Index dictionaryIndex) {
        return new Row(this.index, rowIndex, dictionaryIndex);
    }

    static final class Serializer implements RAFListSerializer<HtmlEntry> {

        final Dictionary dictionary;

        Serializer(Dictionary dictionary) {
            this.dictionary = dictionary;
        }

        @Override
        public HtmlEntry read(DataInput raf, final int index) throws IOException {
            return new HtmlEntry(dictionary, raf, index);
        }

        @Override
        public void write(DataOutput raf, HtmlEntry t) throws IOException {
            t.write(raf);
        }
    }

    public String getRawText(final boolean compact) {
        return title + ":\n" + getHtml();
    }

    @Override
    public int compareTo(HtmlEntry another) {
        if (title.compareTo(another.title) != 0) {
            return title.compareTo(another.title);
        }
        return getHtml().compareTo(another.getHtml());
    }

    @Override
    public String toString() {
        return getRawText(false);
    }

    // --------------------------------------------------------------------

    public static class Row extends RowBase {

        boolean isExpanded = false;

        Row(final DataInput raf, final int thisRowIndex,
                final Index index) throws IOException {
            super(raf, thisRowIndex, index);
        }

        Row(final int referenceIndex, final int thisRowIndex,
                final Index index) {
            super(referenceIndex, thisRowIndex, index);
        }

        @Override
        public String toString() {
            return getRawText(false);
        }

        public HtmlEntry getEntry() {
            return index.dict.htmlEntries.get(referenceIndex);
        }

        @Override
        public void print(PrintStream out) {
            final HtmlEntry entry = getEntry();
            out.println("See also HtmlEntry:" + entry.title);
        }

        @Override
        public String getRawText(boolean compact) {
            final HtmlEntry entry = getEntry();
            return entry.getRawText(compact);
        }

        @Override
        public RowMatchType matches(final List<String> searchTokens,
                final Pattern orderedMatchPattern, final Transliterator normalizer,
                final boolean swapPairEntries) {
            final String text = normalizer.transform(getRawText(false));
            if (orderedMatchPattern.matcher(text).find()) {
                return RowMatchType.ORDERED_MATCH;
            }
            for (int i = searchTokens.size() - 1; i >= 0; --i) {
                final String searchToken = searchTokens.get(i);
                if (!text.contains(searchToken)) {
                    return RowMatchType.NO_MATCH;
                }
            }
            return RowMatchType.BAG_OF_WORDS_MATCH;
        }
    }

    public static String htmlBody(final List<HtmlEntry> htmlEntries, final String indexShortName) {
        final StringBuilder result = new StringBuilder();
        for (final HtmlEntry htmlEntry : htmlEntries) {
            final String titleEscaped = StringUtil.escapeUnicodeToPureHtml(htmlEntry.title);
            result.append(String.format("<h1><a href=\"%s\">%s</a></h1>\n<p>%s\n",
                    formatQuickdicUrl(indexShortName, htmlEntry.title), titleEscaped,
                    htmlEntry.getHtml()));
        }
        return result.toString();
    }

    public static String formatQuickdicUrl(final String indexShortName, final String text) {
        assert !indexShortName.contains(":");
        assert text.length() > 0;
        return String.format("q://d?%s&%s", indexShortName, StringUtil.encodeForUrl(text));
    }

    public static boolean isQuickdicUrl(String url) {
        return url.startsWith("q://d?");
    }

    // --------------------------------------------------------------------

    public static final class LazyHtmlLoader {
        final RandomAccessFile raf;
        final long offset;
        final int numBytes;
        final int numZipBytes;

        // Not sure this volatile is right, but oh well.
        volatile SoftReference<String> htmlRef = new SoftReference<String>(null);

        private LazyHtmlLoader(final DataInput inp) throws IOException {
            raf = (RandomAccessFile)inp;
            numBytes = raf.readInt();
            numZipBytes = raf.readInt();
            offset = raf.getFilePointer();
            raf.skipBytes(numZipBytes);
        }

        public String getHtml() {
            String html = htmlRef.get();
            if (html != null) {
                return html;
            }
            System.out.println("Loading Html: numBytes=" + numBytes + ", numZipBytes="
                    + numZipBytes);
            final byte[] bytes = new byte[numBytes];
            final byte[] zipBytes = new byte[numZipBytes];
            synchronized (raf) {
                try {
                    raf.seek(offset);
                    raf.read(zipBytes);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            try {
                StringUtil.unzipFully(zipBytes, bytes);
                html = new String(bytes, "UTF-8");
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            htmlRef = new SoftReference<String>(html);
            return html;
        }
    }

}