/*
 * [ExtractColours.java]
 *
 * Summary: Extracts unnamed colour numbers from style sheets.
 *
 * Copyright: (c) 2009-2017 Roedy Green, Canadian Mind Products, http://mindprod.com
 *
 * Licence: This software may be copied and used freely for any purpose but military.
 *          http://mindprod.com/contact/nonmil.html
 *
 * Requires: JDK 1.8+
 *
 * Created with: JetBrains IntelliJ IDEA IDE http://www.jetbrains.com/idea/
 *
 * Version History:
 *  1.0 2009-04-13 initial release
 *  1.1 2011-11-09 drop + - and x suffixes. Too hard to maintain.
 */
package com.mindprod.repair;

import com.mindprod.commandline.CommandLine;
import com.mindprod.common18.EIO;
import com.mindprod.common18.Misc;
import com.mindprod.csv.CSVReader;
import com.mindprod.csv.CSVWriter;
import com.mindprod.filter.AllButSVNDirectoriesFilter;
import com.mindprod.filter.ExtensionListFilter;
import com.mindprod.htmlmacros.macro.Global;
import com.mindprod.htmlmacros.support.ConfigurationForMindprod;
import com.mindprod.hunkio.HunkIO;

import java.awt.Color;
import java.io.BufferedReader;
import java.io.EOFException;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.TreeMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import static java.lang.System.*;

/**
 * Extracts unnamed colour numbers from style sheets.
 * <p/>
 * Does NOT parse style sheets looking for name comments.
 * All name-assigning must be done to knowncolours.csv.
 * Does not bodify style sheets.
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.1 2011-11-09 drop + - and x suffixes. Too hard to maintain.
 * @see AnnotateColours
 * @since 2009-04-13
 */
public class ExtractColours
    {
    /**
     * how close colours have to be to be listed as close. Difference of 4 or less is considered close.
     */
    private static final int CLOSE = 4;

    private static final int FIRST_COPYRIGHT_YEAR = 2009;

    /**
     * undisplayed copyright notice
     */
    @SuppressWarnings( { "UnusedDeclaration" } )
    private static final String EMBEDDED_COPYRIGHT =
            "Copyright: (c) 2009-2017 Roedy Green, Canadian Mind Products, http://mindprod.com";

    /**
     * /**
     * regex to look for hex colour numbers in a style sheet
     */
    private static final Pattern COLOUR_PATTERN = Pattern.compile( "#\\p{XDigit}{6}" );

    /**
     * track down colours and their descriptions
     */
    private static final TreeMap<String, String> knownColours = new TreeMap<>();

    /**
     * name of file to read CSV colour/description pairs
     */
    private static File colourDescriptionFile;

    private static File sourceDir;

    /**
     * extract unknown colours from the style sheets on the command line
     *
     * @param args command line list of style sheets
     *
     * @throws IOException if trouble reading style sheets
     */
    private static void extractUnknownColours( final String[] args )
            throws IOException
        {
        out.println( "updating: " + colourDescriptionFile );
        CommandLine files = new CommandLine( args, new AllButSVNDirectoriesFilter(), new ExtensionListFilter( "css" ) );
        for ( File file : files )
            {
            final String contents = HunkIO.readEntireFile( file, HunkIO.UTF8 );
            final Matcher m = COLOUR_PATTERN.matcher( contents );
            while ( m.find() )
                {
                // chop lead #
                final String anotherColour = m.group( 0 ).substring( 1 );
                if ( !knownColours.containsKey( anotherColour ) )
                    {
                    err.println( "Warning: unnamed colour: " + anotherColour + " at offset " + m.start( 0 ) + " in "
                                 + file.toString() );
                    knownColours.put( anotherColour, "" );
                    }
                }
            }
        }

    /**
     * find close colours
     */
    private static void findCloseColours()
        {
        for ( String okey : knownColours.keySet() )
            {
            final Color oColor = new Color( Integer.parseInt( okey, 16 ) );
            final String odesc = knownColours.get( okey );
            for ( String ikey : knownColours.keySet() )
                {
                // don't compare with itself, don't compare both outer:inner and inner:outer
                if ( ikey.compareTo( okey ) <= 0 )
                    {
                    continue;
                    }
                final Color iColor = new Color( Integer.parseInt( ikey, 16 ) );
                final int dist = Math.abs( oColor.getRed() - iColor.getRed() )
                                 + Math.abs( oColor.getGreen() - iColor.getGreen() )
                                 + Math.abs( oColor.getBlue() - iColor.getBlue() );
                final String idesc = knownColours.get( ikey );
                // don't report close x11 colours
                if ( dist <= CLOSE )
                    {
                    out.println( "close colours: "
                                 + okey
                                 + " "
                                 + ( odesc.length() > 0 ? odesc : "unnamed" )
                                 + " vs "
                                 + ikey +
                                 " "
                                 + ( idesc.length() > 0 ? idesc : "unnamed" )
                                 + " : difference "
                                 + dist );
                    }
                }
            }
        }

    /**
     * extract unknown colours from the style sheets on the command line
     *
     * @param args command line list of style sheets
     *
     * @throws IOException if trouble reading style sheets
     */
    private static void findUnusedColours( final String[] args )
            throws IOException
        {
        HashSet<String> inuse = new HashSet<>( 1000 );
        CommandLine files = new CommandLine( args, new AllButSVNDirectoriesFilter(), new ExtensionListFilter( "css" ) );
        for ( File file : files )
            {
            final String contents = HunkIO.readEntireFile( file, HunkIO.UTF8 );
            final Matcher m = COLOUR_PATTERN.matcher( contents );
            while ( m.find() )
                {
                // chop lead #
                final String anotherColour = m.group( 0 ).substring( 1 );
                inuse.add( anotherColour );
                }
            }
        for ( String colour : knownColours.keySet() )
            {
            if ( !inuse.contains( colour ) )
                {
                final String odesc = knownColours.get( colour );
                err.println( "Colour " + colour + " " + ( odesc.length() > 0 ? odesc : "unnamed" ) + " is not used in" +
                             " any of the style sheets." );
                }
            }
        }

    /**
     * read existing list of known colours
     *
     * @throws IOException if trouble reading CSV list of known colours
     */
    private static void readKnownColours() throws IOException
        {
        // O P E N
        final FileReader fr = new FileReader( colourDescriptionFile );
        final BufferedReader br = new BufferedReader( fr,
                24 * 1024
                /* 24K chars (48K bytes), 75% of allocation is optimal */ );
        // reader, separatorChar, quoteChar, commentChars, hideComments, trimQuoted, trimUnquoted,
        // allowMultipleLineFields
        final CSVReader r = new CSVReader( br,
                ',',
                '\"',
                "#",
                true,
                true
                /* trimQuoted */,
                true
                /* trimUnquoted */,
                false );
        final HashMap<String, String> dupDescDetector = new HashMap<>( 1000 );
        try
            {
            //noinspection InfiniteLoopStatement
            while ( true )
                {
                final String colour = r.get();
                if ( colour == null )
                    {
                    // bypass blank line., we have skipped to next line
                    continue;
                    }
                final String desc = r.get();
                if ( desc == null )
                    {
                    // bypass unnamed colour, we have skipped to next line
                    continue;
                    }
                // lookup by colour
                final String prevDesc = knownColours.put( colour, desc );
                if ( prevDesc != null )
                    {
                    err.println( "Error: Duplicate entry for colour number " + colour + " : " + desc + " : " +
                                 prevDesc );
                    }
                // lookup by desc
                final String prevColour = dupDescDetector.put( desc, colour );
                if ( prevColour != null && desc.length() > 0 )
                    {
                    err.println( "Warning: Duplicate entry for description " + desc + " : " + colour + " : " +
                                 prevColour );
                    }
                r.skipToNextLine();
                }
            }
        catch ( EOFException e )
            {
            r.close();
            }
        }

    /**
     * write out our new list of know colours, ready to have descriptions added. Will be sorted in RGB order.
     *
     * @throws IOException if trouble exporting data
     */
    private static void writeColours() throws IOException
        {
        // O P E N
        final PrintWriter prw = EIO.getPrintWriter( colourDescriptionFile, 24 * 1024, EIO.UTF8 );
        // writer, quoteLevel, separatorChar, quoteChar, commentChar, trim
        final CSVWriter w = new CSVWriter( prw, -1 /* extra space */, ',', '\"', '#', true );
        w.nl( "Canadian Mind Products Stylesheet Colours" );
        for ( Map.Entry<String, String> entry : knownColours.entrySet() )
            {
            // This code does not require an expensive get lookup to find the value.
            final String colourNumber = entry.getKey();
            final String desc = entry.getValue();
            w.put( colourNumber );
            w.put( desc );
            w.nl();
            } // end for
        w.close();
        }

    /**
     * Extracts lines in files that contain a given string.
     *
     * @param args style sheets to scan, e.g. E:\mindprod\mindprod.css
     */
    public static void main( String[] args )
        {
        Global.installConfiguration( new ConfigurationForMindprod() );
        // combine dirsWithMacros and dirsWithIncludes into dirsToProcess;
        sourceDir = new File( Global.configuration.getSourceDirWithSlashes() );
        colourDescriptionFile = new File( sourceDir, "repair/knowncolours.csv" );
        try
            {
            // read existing list of known colours
            readKnownColours();
            // extract unknown colours from the style sheets on the command line
            extractUnknownColours( args );
            // find colours defined in the csv file but not used in style sheets
            findUnusedColours( args );
            // find close colours
            findCloseColours();
            // write out our new list of know colours, ready to have descriptions added.
            writeColours();
            // generate code for inclusion into Palette.
            out.println( "Done" );
            }
        catch ( Exception e )
            {
            e.printStackTrace( err );
            err.println();
            }
        Misc.trackLastThread();
        System.exit( 0 );
        } // end main
    }