/**
 * Module : Reporter.java Copyright : (c) 2012, Galois, Inc.
 *
 * Maintainer : Stability : Provisional Portability: Portable
 *
 * 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.
 *
 * @author Benjamin Jones <bjones@galois.com>
 */
package com.galois.fiveui;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.google.common.collect.Lists;
import com.googlecode.jatl.Html;

/**
 * Reporter is responsible for turning a list of results from a FiveUI run and
 * and generating various reports which summarize the results. The reports are
 * generated in HTML and returned as human readable strings by getSummaryPage(),
 * getURLPage(), and getRulePage(). The client is responsible for writing them
 * to .html files (or whatever).
 * 
 * @author bjones
 * 
 */
public class Reporter {

    /** see sortBy* and computeSummaryStats methods for map semantics */
    private final Map<String, List<Result>> _byURLMap;
    private final Map<String, List<Result>> _byRuleMap;
    private final Map<String, int[]> _passFailMap;
    private Map<String, String> _ruleNameToDesc;
    private static String GLOBAL_CSS = "h1 { font-size: 150%; }"
            + "h2 { font-size: 110%; }"
            + "li { margin: 5 0 0 0; }"
            + "table { border: 1px solid grey; cellpadding: 5%; width: 200px; }\n"
            + "td.pass-number{ text-align: right;color: green; }\n"
            + "td.fail-number{ text-align: right;color: red; }\n"
            + "td.text{ text-align: left; }\n" + "th { font-weight: bold; }\n"
            + "td, th { border: 1px solid grey; }\n"
            + ".hlRow { background: #EEEEEE; }\n"
            + ".regRow { background: #FFFFFF; }\n";

    /**
     * Construct a Reporter object. The constructor takes a list of results and
     * uses them to populate various maps used in reporting.
     * 
     * @param results
     *            a list of Result objects
     */
    public Reporter(List<Result> results) {
        this._byURLMap = sortByURL(results);
        this._byRuleMap = sortByRule(results);
        this._passFailMap = computeSummaryStats(results);
        this._ruleNameToDesc = extractRuleDesc(results);
    }

    /**
     * Build the HTML markup for a summary page based on the precomputed map
     * this._passFailMap.
     * 
     * @return String containing human-readable HTML representing a summary page
     */
    public String getSummary() {
        StringWriter summaryPage = new StringWriter();
        final Map<String, int[]> scopedMap = this._passFailMap;
        Html page = new Html(summaryPage);
        page = makeHead(page, "Summary of Results");
        page = new Html(page) {
            {
                h1().text("Headless Run Summary").end();
                p();
                ul();
                li().a().href("byURL.html").text("Results organized by URL")
                        .end().end();
                li().a().href("byRule.html").text("Results organized by Rule")
                        .end().end();
                end();
                end();
                p();
                div().id("stats");
                makeSummaryStats(scopedMap);
                end();
                end();
                endAll();
                done();
            }

            /**
             * Report statistics on the headless run. Note, "pass" means the URL
             * passed all tests in the ruleset, but "fail" can be reported for
             * the same test on multiple offenders in the page.
             */
            Html makeSummaryStats(Map<String, int[]> passFailMap) {
                int uniqueURLs = passFailMap.size();
                int[] passFailList;

                p();
                h3().text("Unique URLs: ");
                span().classAttr("number").text(String.valueOf(uniqueURLs))
                        .end();
                end().end();

                p();
                table().id("stats-table");
                tr();
                th().text("URL").end();
                th().text("Pass").end();
                th().text("Fail").end();
                end();
                int i = 0; // index for **alternate row highlighting**
                List<String> sortedKeys = Lists.newArrayList();
                sortedKeys.addAll(passFailMap.keySet());
                Collections.sort(sortedKeys);
                for (String key : sortedKeys) {
                    passFailList = passFailMap.get(key);
                    tr().classAttr(i % 2 == 0 ? "hlRow" : "regRow");
                    td().classAttr("text").a().href(key).text(key).end().end();
                    td().classAttr("pass-number")
                            .text(String.valueOf(passFailList[0])).end();
                    td().classAttr("fail-number")
                            .text(String.valueOf(passFailList[1])).end();
                    end();
                    i++;
                }
                end(); // end <table>
                return end(); // end <p>
            }
        };
        return summaryPage.getBuffer().toString();
    }

    /**
     * Build the HTML markup for a report page sorted by URL.
     * 
     * @return String containing human-readable HTML representing a report page
     */
    public String getByURL() {
        StringWriter byURLPage = new StringWriter();
        final Map<String, List<Result>> scopedMap = this._byURLMap;
        Html page = new Html(byURLPage);
        page = makeHead(page, "Results sorted by URL");
        page = new Html(page) {
            {
                body();
                h1().text("Results by URL").end();
                ol();
                List<String> sortedKeys = Lists.newArrayList();
                sortedKeys.addAll(scopedMap.keySet());
                Collections.sort(sortedKeys);
                for (String url : sortedKeys) {
                    li().h2().a().href(url).text(url).end().end();
                    ul();
                    int i = 0;
                    for (Result r : scopedMap.get(url)) {
                        String cAttr = i % 2 == 0 ? "hlRow" : "regRow";

                        // format an individual Result for this url:
                        li().classAttr(cAttr).b().text(r.getRuleName()).end();
                        resultToHtml(this, r, cAttr);
                        end();
                        i++;
                    }
                    end();
                    end();
                }
                endAll();
                done();
            }

        };
        return byURLPage.getBuffer().toString();
    }

    
    
    /**
     * Build the HTML markup for a report page sorted by rule name.
     * 
     * @return String containing human-readable HTML representing a report page
     */
    public String getByRule() {
        StringWriter byRulePage = new StringWriter();
        final Map<String, List<Result>> scopedMap = this._byRuleMap;
        final Map<String, String> scopedRuleNameToDesc = this._ruleNameToDesc;
        Html page = new Html(byRulePage);
        page = makeHead(page, "Results sorted by rule");
        page = new Html(page) {
            {
                h1().text("Results by Rule").end();
                ul();
                List<String> sortedKeys = new ArrayList<String>();
                sortedKeys.addAll(scopedMap.keySet());
                Collections.sort(sortedKeys);
                for (String rule : sortedKeys) {
                    li();
                    b().text(rule).end()
                            .text(": " + scopedRuleNameToDesc.get(rule));
                    ul();
                    int i = 0;
                    for (Result r : scopedMap.get(rule)) {
                        String cAttr = i % 2 == 0 ? "hlRow" : "regRow";
                        
                        li().classAttr(cAttr).b().text(r.getURL()).end();
                        resultToHtml(this, r, cAttr);
                        end();
                        i++;
                    }
                    end();
                    end();
                }
                endAll();
                done();
            }
        };
        return byRulePage.getBuffer().toString();
    }


    private void resultToHtml(Html html, Result r, String cAttr) {
        
        html.ul();
        html.li().b().text("Description:").end();
        html.text(r.getRuleDesc()).end();
        
        html.li().b().text("Message:").end();
        html.text(r.getMsg()).end();

        html.li().b().text("xpath:").end();
        html.text(r.getXpath()).end();
        
        html.li().b().text("Severity:").end();
        html.text(r.getType().toString()).end();
        
    	html.li().b().text("Browser:").end();
    	// unit tests use a null webdriver object
        if (null != r.getDriver()) {
        	html.text(r.getDriver().toString()).end();
        }
        
        html.li().b().text("Url:").end();
        html.a().href(r.getURL()).text(r.getURL()).end().end();

        html.end();
    }
    
    /**
     * Utility method to take all the reports and write them to standard file
     * names under a given directory.
     * 
     * @param dirName
     *            name of the directory where the reports should be written
     * @throws IOException
     */
    public void writeReportsToDir(String dirName) throws IOException {
        PrintWriter summaryFile = new PrintWriter(new FileWriter(dirName
                + File.separator + "summary.html"));
        PrintWriter byURLFile = new PrintWriter(new FileWriter(dirName
                + File.separator + "byURL.html"));
        PrintWriter byRuleFile = new PrintWriter(new FileWriter(dirName
                + File.separator + "byRule.html"));
        summaryFile.write(this.getSummary());
        summaryFile.close();
        byURLFile.write(this.getByURL());
        byURLFile.close();
        byRuleFile.write(this.getByRule());
        byRuleFile.close();
    }

    /** Private fields **/

    private Html makeHead(Html page, final String title) {
        return new Html(page) {
            {
                html();
                head();
                title().text(title).end();
                style().type("text/css").text(GLOBAL_CSS).end();
                end();
                body();
            }
        };
    }

    /**
     * Populate a Map<String, List<Result>> representing the results sorted by
     * URL.
     * 
     * @param results
     *            a list of results
     * @return a map representing the results sorted by URL.
     */
    private Map<String, List<Result>> sortByURL(List<Result> results) {
        /** map semantics: Map< url, [rule1, rule2, ...] > */
        Map<String, List<Result>> map = new HashMap<String, List<Result>>();
        String url;
        List<Result> list;
        for (Result r : results) {
            url = r.getURL();
            if (map.containsKey(url)) {
                list = map.get(url);
                list.add(r);
            } else {
                list = new ArrayList<Result>();
                list.add(r);
                map.put(url, list);
            }
        }
        return map;
    }

    /**
     * Populate a Map<String, List<Result>> representing the results sorted by
     * rule name.
     * 
     * @param results
     *            a list of results
     * @return a map representing the results sorted by rule name.
     */
    private Map<String, List<Result>> sortByRule(List<Result> results) {
        /** map semantics: Map< rule, [url1, url2, ...] > */
        Map<String, List<Result>> map = new HashMap<String, List<Result>>();
        String rule;
        List<Result> list;
        for (Result r : results) {
            rule = r.getRuleName();
            if (map.containsKey(rule)) {
                list = map.get(rule);
                list.add(r);
            } else {
                list = new ArrayList<Result>();
                list.add(r);
                map.put(rule, list);
            }
        }
        return map;
    }

    /**
     * Build a map of ruleName -> ruleDesc entries occurring in the given list
     * of results.
     * 
     * @param results
     *            a list of results
     * @return a map associating rule names to rule descriptions
     */
    private Map<String, String> extractRuleDesc(List<Result> results) {
        Map<String, String> assoc = new HashMap<String, String>();
        for (Result r : results)
            if (!assoc.containsKey(r.getRuleName()))
                assoc.put(r.getRuleName(), r.getRuleDesc());
        return assoc;
    }

    /**
     * Compute summary statistics from the results list. This includes number of
     * passes and fails for each URL checked.
     * 
     * @param results
     *            a list of results
     * @return a map representing the results sorted by rule name.
     */
    private Map<String, int[]> computeSummaryStats(List<Result> results) {
        /** passFailMap semantics: Map<url, {#pass, #fail}> */
        Map<String, int[]> passFailMap = new HashMap<String, int[]>();
        String url;
        int pass, fail;
        int[] passFailList;
        Pattern numberPassedPattern = Pattern.compile("passed ([0-9]+) tests");
        Matcher matcher;

        for (Result result : results) {
            pass = fail = 0;
            url = result.getURL();
            if (result.getType() == ResType.Pass) {
                // now we have to parse out how many tests passed
                matcher = numberPassedPattern.matcher(result.getMsg());
                if (matcher.find())
                    pass = Integer.parseInt(matcher.group(1)); // throws
                                                               // exception if
                                                               // parse fails
            } else if (result.getType() == ResType.Error) {
                // each error result corresponds to one test
                fail = 1;
            }

            if (passFailMap.containsKey(url)) {
                passFailList = passFailMap.get(url);
            } else {
                passFailList = new int[] { 0, 0 };
                passFailMap.put(url, passFailList);
            }
            passFailList[0] += pass;
            passFailList[1] += fail;
        }
        return passFailMap;
    }
}