/*
 * [USPostageRates.java]
 *
 * Summary: Probe US post office to find the latest postage rates to post at http://mindprod.com/jgloss/postage.html.
 *
 * Copyright: (c) 2014-2017 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 2014-04-06 initial release
 *  1.1 2015-02-05 make date of probe track today's date.
 *                 New style probe. Tighten finder so will ignore the $400 entries.
 *                 N O L O N G E R W O R K S. now 2 pages of HTTPS:
 *  1.2 2016-06-22 Use downloaded files rather than web calculator.
 */
package com.mindprod.repair;

import com.mindprod.common18.BigDate;
import com.mindprod.common18.EIO;
import com.mindprod.common18.ST;
import com.mindprod.csv.CSVReader;
import com.mindprod.fastcat.FastCat;
import com.mindprod.filetransfer.Download;

import java.io.File;
import java.io.IOException;
import java.text.DecimalFormat;

import static java.lang.System.*;

/**
 * Probe US post office to find the latest postage rates to post at http://mindprod.com/jgloss/postage.html.
 * Trigger with E:\com\mindprod\repair\GrabPostageRates.exe
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.2 2016-06-22 Use downloaded files rather than web calculator.
 * @see CanadaPostageRates
 * @since 2014-04-06
 */
class USPostageRates
    {
    /**
     * format for display and input of sale amount
     */
    private static final DecimalFormat PRICEFORMAT =
            new DecimalFormat( "#,##0.00" );

    private static final double[] prices = new double[ 12 ];

    /**
     * cost of one basic US stamp, used for computing ratios
     */
    private static double usBaseRate;

    private static int lineCounter;

    private static void downloadFiles()
        {
        out.println( "Downloading rate files..." );
        if ( !Download.downloadOneFile( "https://www.usps.com/business/prices/m-fcm-eddm-retail.csv", "C:/temp/domestic.csv", false ) )
            {
            err.println( "Unable to download US domestic rates." );
            System.exit( 2 );
            }
        if ( !Download.downloadOneFile( "https://www.usps.com/business/prices/m-fcmi-letters.csv", "C:/temp/international.csv", false ) )
            {
            err.println( "Unable to download US international rates." );
            System.exit( 2 );
            }
        }

    private static void extractPrices()
        {
        try
            {
            CSVReader domestic = new CSVReader( EIO.getBufferedReader( new File( "C:/temp/domestic.csv" ), 32 * 1024, EIO.UTF8 ) );
            for ( int i = 0; i < 5; i++ )
                {
                domestic.skipToNextLine();
                }
            domestic.skip( 1 );
            prices[ 0 ] = domestic.getDouble();
            usBaseRate = prices[ 0 ];
            domestic.skipToNextLine();
            domestic.skip( 1 );
            prices[ 1 ] = domestic.getDouble();
            domestic.skipToNextLine();
            domestic.skip( 1 );
            prices[ 2 ] = domestic.getDouble();
            domestic.skipToNextLine();
            domestic.skip( 1 );
            prices[ 3 ] = domestic.getDouble();
            domestic.close();
            CSVReader international = new CSVReader( EIO.getBufferedReader( new File( "C:/temp/international.csv" ), 32 * 1024, EIO.UTF8 ) );
            for ( int i = 0; i < 5; i++ )
                {
                international.skipToNextLine();
                }
            // Canada is group 1, Britain in group 3
            international.skip( 1 );
            prices[ 4 ] = international.getDouble();
            international.skip( 1 );
            prices[ 8 ] = international.getDouble();
            international.skipToNextLine();
            international.skip( 1 );
            prices[ 5 ] = international.getDouble();
            international.skip( 1 );
            prices[ 9 ] = international.getDouble();
            international.skipToNextLine();
            international.skip( 1 );
            prices[ 6 ] = international.getDouble();
            international.skip( 1 );
            prices[ 10 ] = international.getDouble();
            international.skipToNextLine();
            international.skip( 1 );
            prices[ 7 ] = international.getDouble();
            international.skip( 1 );
            prices[ 11 ] = international.getDouble();
            international.close();
            }
        catch ( IOException e )
            {
            err.println( "USPS file format has changed." );
            System.exit( 2 );
            }
        }

    /**
     * main method, probes all the variants of mail from the USA
     *
     * @return html text to list the prices and descriptions
     */
    static String generateAllUSPrices()
        {
        downloadFiles();
        extractPrices();
        final String prelude1 = "<table class=\"standard\"><caption class=\"hidden\">American Postage Rates</caption> <colgroup><col\n" +
                                "style=\"text-align:right\"> <col style=\"text-align:right\"></colgroup>\n" +
                                "<thead><tr><th colspan=\"4\" style=\"text-align:center\">American Postage\n" +
                                "Rates</th></tr>\n" +
                                "<tr><th colspan=\"4\" style=\"text-align:center\"><!-- macro Revised ";
        final String prelude2 = BigDate.localToday().toString();
        final String prelude3 = " --></th></tr>\n" +
                                "<tr><th>Cost $USD</th>\n" +
                                "<th>Ratio</th>\n" +
                                "<th>Type</th>\n" +
                                "<th>Weight</th></tr></thead>\n" +
                                "<tbody>";
        final String postlude = "<tr><td>&nbsp;</td>\n" +
                                "<td>&nbsp;</td>\n" +
                                "<td><a class=\"gov\" href=\"https://ircalc.usps.com/\">Others</a></td>\n" +
                                "<td>&nbsp;</td></tr></tbody></table>";
        final FastCat sb = new FastCat( 20 );
        sb.append( prelude1, prelude2, prelude3 );
        sb.append( generateOneUSTableLine( "light letter within the USA", 0, 1 /* low/high weight */, prices[ 0 ] ) );
        sb.append( generateOneUSTableLine( "midweight letter within the USA", 1, 2, prices[ 1 ] ) );
        sb.append( generateOneUSTableLine( "overweight letter within the USA", 2, 3, prices[ 2 ] ) );
        sb.append( generateOneUSTableLine( "heavy letter within the USA", 3, 3.5, prices[ 3 ] ) );
        // find out cost of US letters to Canada
        sb.append( generateOneUSTableLine( "light letter to Canada", 0, 1 /*  low/high weight */, prices[ 4 ] ) );
        sb.append( generateOneUSTableLine( "midweight letter to Canada", 1, 2, prices[ 5 ] ) );
        sb.append( generateOneUSTableLine( "overweight letter to Canada", 2, 3, prices[ 6 ] ) );
        sb.append( generateOneUSTableLine( "heavy letter to Canada", 3, 3.5, prices[ 7 ] ) );
        // find out to US letters to Britain
        sb.append( generateOneUSTableLine( "light International letter. Rate varies by country. \n" +
                                           "England (group 3) shown", 0, 1 /*  low/high weight */, prices[ 8 ] ) );
        sb.append( generateOneUSTableLine( "midweight International letter. Rate varies by country. \n" +
                                           "England shown", 1, 2, prices[ 9 ] ) );
        sb.append( generateOneUSTableLine( "overweight International letter. Rate varies by country. \n" +
                                           "England shown", 2, 3, prices[ 10 ] ) );
        sb.append( generateOneUSTableLine( "heavy International letter. Rate varies by country. \n" +
                                           "England shown", 3, 3.5, prices[ 11 ] ) );
        sb.append( postlude );
        return sb.toSeparatedList( '\n' );
        }

    /**
     * @param desc   description e.g. light letter with the USA
     * @param fromOz low bound on weight
     * @param toOz   high bound on weight
     * @param price  without lead $
     *
     * @return HTML text
     */
    private static String generateOneUSTableLine( final String desc, final double fromOz, final double toOz, final double price )
        {
        // group lines by fours, alternating light/dark backgrounds
        final String css = ( lineCounter++ / 4 % 2 == 0 ) ? "stripe1" : "stripe2";
        final FastCat sb = new FastCat( 17 );
        sb.append( "<tr class=\"", css, "\">" );
        sb.append( "<td>$", PRICEFORMAT.format( price ), "</td>" );
        sb.append( "<td>", PRICEFORMAT.format( price / usBaseRate ), "</td>" );
        sb.append( "<td>", desc, "</td>" );
        sb.append( "<td>", tidyFormat( fromOz ), " to ", tidyFormat( toOz ), " ounces</td></tr>" );
        return sb.toString();
        }

    private static String tidyFormat( double d )
        {
        final String s = Double.toString( d );
        return ST.chopTrailingString( s, ".0" );
        }

    public static void main( String[] args ) throws IOException
        {
        out.println( generateAllUSPrices() );
        }
    }