/*
 * Copyright (C) 2007 Apple Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */

var count1 = output1.length;
var count2 = output2.length;

var itemTotals1 = {};
itemTotals1.length = count1;

var total1 = 0;
var categoryTotals1 = {};
var testTotalsByCategory1 = {};

var mean1 = 0;
var categoryMeans1 = {};
var testMeansByCategory1 = {};

var stdDev1 = 0;
var categoryStdDevs1 = {};
var testStdDevsByCategory1 = {};

var stdErr1 = 0;
var categoryStdErrs1 = {};
var testStdErrsByCategory1 = {};

var itemTotals2 = {};
itemTotals2.length = count2;

var total2 = 0;
var categoryTotals2 = {};
var testTotalsByCategory2 = {};

var mean2 = 0;
var categoryMeans2 = {};
var testMeansByCategory2 = {};

var stdDev2 = 0;
var categoryStdDevs2 = {};
var testStdDevsByCategory2 = {};

var stdErr2 = 0;
var categoryStdErrs2 = {};
var testStdErrsByCategory2 = {};

function initialize()
{
    itemTotals1 = {total: []};

    for (var i = 0; i < categories.length; i++) {
        var category = categories[i];
        itemTotals1[category] = [];
        categoryTotals1[category] = 0;
        testTotalsByCategory1[category] = {};
        categoryMeans1[category] = 0;
        testMeansByCategory1[category] = {};
        categoryStdDevs1[category] = 0;
        testStdDevsByCategory1[category] = {};
        categoryStdErrs1[category] = 0;
        testStdErrsByCategory1[category] = {};
    }

    for (var i = 0; i < tests.length; i++) {
        var test = tests[i];
        itemTotals1[test] = [];
        var category = test.replace(/-.*/, "");
        testTotalsByCategory1[category][test] = 0;
        testMeansByCategory1[category][test] = 0;
        testStdDevsByCategory1[category][test] = 0;
        testStdErrsByCategory1[category][test] = 0;
    }

    for (var i = 0; i < count1; i++) {
        itemTotals1["total"][i] = 0;
        for (var category in categoryTotals1) {
            itemTotals1[category][i] = 0;
            for (var test in testTotalsByCategory1[category]) {
                itemTotals1[test][i] = 0;
            }
        }
    }

    itemTotals2 = {total: []};

    for (var i = 0; i < categories.length; i++) {
        var category = categories[i];
        itemTotals2[category] = [];
        categoryTotals2[category] = 0;
        testTotalsByCategory2[category] = {};
        categoryMeans2[category] = 0;
        testMeansByCategory2[category] = {};
        categoryStdDevs2[category] = 0;
        testStdDevsByCategory2[category] = {};
        categoryStdErrs2[category] = 0;
        testStdErrsByCategory2[category] = {};
    }

    for (var i = 0; i < tests.length; i++) {
        var test = tests[i];
        itemTotals2[test] = [];
        var category = test.replace(/-.*/, "");
        testTotalsByCategory2[category][test] = 0;
        testMeansByCategory2[category][test] = 0;
        testStdDevsByCategory2[category][test] = 0;
        testStdErrsByCategory2[category][test] = 0;
    }

    for (var i = 0; i < count2; i++) {
        itemTotals2["total"][i] = 0;
        for (var category in categoryTotals2) {
            itemTotals2[category][i] = 0;
            for (var test in testTotalsByCategory2[category]) {
                itemTotals2[test][i] = 0;
            }
        }
    }

}

function computeItemTotals(output, itemTotals)
{
    for (var i = 0; i < output.length; i++) {
        var result = output[i];
        for (var test in result) {
            var time = result[test];
            var category = test.replace(/-.*/, "");
            itemTotals["total"][i] += time;
            itemTotals[category][i] += time;
            itemTotals[test][i] += time;
        }
    }
}

function computeTotals(output, categoryTotals, testTotalsByCategory)
{
    var total = 0;

    for (var i = 0; i < output.length; i++) {
        var result = output[i];
        for (var test in result) {
            var time = result[test];
            var category = test.replace(/-.*/, "");
            total += time;
            categoryTotals[category] += time;
            testTotalsByCategory[category][test] += time;
        }
    }

    return total;
}

function computeMeans(count, total, categoryTotals, categoryMeans, testTotalsByCategory, testMeansByCategory)
{
    var mean = total / count;
    for (var category in categoryTotals) {
        categoryMeans[category] = categoryTotals[category] / count;
        for (var test in testTotalsByCategory[category]) {
            testMeansByCategory[category][test] = testTotalsByCategory[category][test] / count;
        }
    }
    return mean;
}

function standardDeviation(mean, items)
{
    var deltaSquaredSum = 0;
    for (var i = 0; i < items.length; i++) {
        var delta = items[i] - mean;
        deltaSquaredSum += delta * delta;
    }
    variance = deltaSquaredSum / (items.length - 1);
    return Math.sqrt(variance);
}

function computeStdDevs(mean, itemTotals, categoryStdDevs, categoryMeans, testStdDevsByCategory, testMeansByCategory)
{
    var stdDev = standardDeviation(mean, itemTotals["total"]);
    for (var category in categoryStdDevs) {
        categoryStdDevs[category] = standardDeviation(categoryMeans[category], itemTotals[category]);
    }
    for (var category in categoryStdDevs) {
        for (var test in testStdDevsByCategory[category]) {
            testStdDevsByCategory[category][test] = standardDeviation(testMeansByCategory[category][test], itemTotals[test]);
        }
    }
    return stdDev;
}

function computeStdErrors(count, stdDev, categoryStdErrs, categoryStdDevs, testStdErrsByCategory, testStdDevsByCategory)
{
    var sqrtCount = Math.sqrt(count);
    
    var stdErr = stdDev / sqrtCount;
    for (var category in categoryStdErrs) {
        categoryStdErrs[category] = categoryStdDevs[category] / sqrtCount;
    }
    for (var category in categoryStdDevs) {
        for (var test in testStdErrsByCategory[category]) {
            testStdErrsByCategory[category][test] = testStdDevsByCategory[category][test] / sqrtCount;
        }
    }

    return stdErr;
}

var tDistribution = [NaN, NaN, 12.71, 4.30, 3.18, 2.78, 2.57, 2.45, 2.36, 2.31, 2.26, 2.23, 2.20, 2.18, 2.16, 2.14, 2.13, 2.12, 2.11, 2.10, 2.09, 2.09, 2.08, 2.07, 2.07, 2.06, 2.06, 2.06, 2.05, 2.05, 2.05, 2.04, 2.04, 2.04, 2.03, 2.03, 2.03, 2.03, 2.03, 2.02, 2.02, 2.02, 2.02, 2.02, 2.02, 2.02, 2.01, 2.01, 2.01, 2.01, 2.01, 2.01, 2.01, 2.01, 2.01, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.99, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.98, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.97, 1.96];
var tMax = tDistribution.length;
var tLimit = 1.96;

function tDist(n)
{
    if (n > tMax)
        return tLimit;
    return tDistribution[n];
}


function formatMean(meanWidth, mean, stdErr, count)
{
    var meanString = mean.toFixed(1).toString();
    while (meanString.length < meanWidth) {
        meanString = " " + meanString;
    }

    var error = "+/- " + ((tDist(count) * stdErr / mean) * 100).toFixed(1) + "% ";

    return meanString + "ms " + error;
}

function computeLabelWidth()
{
    var width = "Total".length;
    for (var category in categoryMeans1) {
        if (category.length + 2 > width)
            width = category.length + 2;
    }
    for (var i = 0; i < tests.length; i++) {
        var shortName = tests[i].replace(/^[^-]*-/, "");
        if (shortName.length + 4 > width)
            width = shortName.length + 4;
    }

    return width;
}

function computeMeanWidth(mean, categoryMeans, testMeansByCategory)
{
    var width = mean.toFixed(1).toString().length;
    for (var category in categoryMeans) {
        var candidate = categoryMeans[category].toFixed(1).toString().length;
        if (candidate > width)
            width = candidate;
        for (var test in testMeansByCategory[category]) {
            var candidate = testMeansByCategory[category][test].toFixed(1).toString().length;
            if (candidate > width)
                width = candidate;
        }
    }

    return width;
}

function pad(str, n)
{
    while (str.length < n) {
        str += " ";
    }
    return str;
}

function resultLine(labelWidth, indent, label, meanWidth1, mean1, stdErr1, meanWidth2, mean2, stdErr2)
{
    result = pad("", indent);    
    result += label + ": ";
    result = pad(result, labelWidth + 2);

    var t = (mean1 - mean2) / (Math.sqrt((stdErr1 * stdErr1) + (stdErr1 * stdErr2))); 
    var df = count1 + count2 - 2;

    var statisticallySignificant = (Math.abs(t) > tDist(df+1));
    var diff = mean2 - mean1;
    var percentage = 100 * diff / mean1;
    var isFaster = diff < 0;
    var probablySame = (percentage < 0.1) && !statisticallySignificant;

    var diffSummary;
    var diffDetail;

    if (probablySame) {
        diffSummary = "-";
        diffDetail = "";
    } else if (!statisticallySignificant) {
        diffSummary = "??";
        diffDetail =  "    not conclusive: might be " + Math.abs(percentage).toFixed(1).toString() + "% ";
        diffDetail += (isFaster ? "faster" : "*slower*");
    } else {
        diffSummary = Math.abs(percentage).toFixed(1).toString() + "% " + (isFaster ? "faster" : "*slower*");
        diffDetail = "    significant"; 
    }

    return result + pad(diffSummary, 16) + formatMean(meanWidth1, mean1, stdErr1, count1) + "  " + formatMean(meanWidth2, mean2, stdErr2, count2) + diffDetail;
}

function printOutput()
{
    var labelWidth = computeLabelWidth();
    var meanWidth1 = computeMeanWidth(mean1, categoryMeans1, testMeansByCategory1);
    var meanWidth2 = computeMeanWidth(mean2, categoryMeans2, testMeansByCategory2);

    print("\n");
    var header = "TEST";
    while (header.length < labelWidth)
        header += " ";
    header += "  COMPARISON            FROM                 TO             DETAILS";
    print(header);
    print("");
    print("=============================================================================");
    print("");
    print(resultLine(labelWidth, 0, "** TOTAL **", meanWidth1, mean1, stdErr1, meanWidth2, mean2, stdErr2));
    print("");
    print("=============================================================================");

    for (var category in categoryMeans1) {
        print("");
        print(resultLine(labelWidth, 2, category,
                         meanWidth1, categoryMeans1[category], categoryStdErrs1[category],
                         meanWidth2, categoryMeans2[category], categoryStdErrs2[category]));
        for (var test in testMeansByCategory1[category]) {
            var shortName = test.replace(/^[^-]*-/, "");
            print(resultLine(labelWidth, 4, shortName, 
                             meanWidth1, testMeansByCategory1[category][test], testStdErrsByCategory1[category][test],
                             meanWidth2, testMeansByCategory2[category][test], testStdErrsByCategory2[category][test]));
        }
    }
}

initialize();

computeItemTotals(output1, itemTotals1);
computeItemTotals(output2, itemTotals2);

total1 = computeTotals(output1, categoryTotals1, testTotalsByCategory1);
total2 = computeTotals(output2, categoryTotals2, testTotalsByCategory2);

mean1 = computeMeans(count1, total1, categoryTotals1, categoryMeans1, testTotalsByCategory1, testMeansByCategory1);
mean2 = computeMeans(count2, total2, categoryTotals2, categoryMeans2, testTotalsByCategory2, testMeansByCategory2);

stdDev1 = computeStdDevs(mean1, itemTotals1, categoryStdDevs1, categoryMeans1, testStdDevsByCategory1, testMeansByCategory1);
stdDev2 = computeStdDevs(mean2, itemTotals2, categoryStdDevs2, categoryMeans2, testStdDevsByCategory2, testMeansByCategory2);

stdErr1 = computeStdErrors(count1, stdDev1, categoryStdErrs1, categoryStdDevs1, testStdErrsByCategory1, testStdDevsByCategory1);
stdErr2 = computeStdErrors(count2, stdDev2, categoryStdErrs2, categoryStdDevs2, testStdErrsByCategory2, testStdDevsByCategory2);

printOutput();
