User:OrphanBot/libPearle2.pl

From Wikipedia, the free encyclopedia


### IMPORTANT ###

# This code is released into the public domain.

### RECENT CHANGES ###

# 30 Nov 2005: Created, based off of the  12 Nov 2005 version of Pearle Wisebot
# 15 Feb 2006: Modifed "retry" to work with any function that signals failure by dying, modified to use a simple exponential backoff formula
#              Simplified "limit" code, modified to take an optional parameter
#              Added "config" function as a clean interface to change internal parameters
#              Modified Wiki-access functions for use with the new "retry" function
#              Cleanup of boolean config vars to use standard Perl boolean conventions
# 28 Feb 2006: Added checkLogin bottleneck, option to allow editing while logged out
#              Added support for proxy servers
#  8 Mar 2006: Added support for getting a user's contributions
#              Added support for retrieving logs
#              Separated out some common regex parts into variables
# 29 Mar 2006: Added protection against Unicode in URLs
#              Made thrown exceptions consistent
#              Sanity-checking on postPage: talkpage without article, userpage or user talkpage without user
# 17 May 2005: Improved log retrieval
# 12 Jul 2007: Added timestamp to information retrieved from logs

# Errors thrown by this package always begin with a three-digit number
#     4xx: HTTP client errors
#     505: Server error: HTTP version not supported
#     509: Server error: Bandwidth exceeded
#
#     900: Unspecified internal error.
#     901: Library not initialized.  You didn't call Pearle::init() before calling this function.
#     902: Parameter error.  You made a function call, but forgot a mandatory parameter, or provided an invalid one.
#
#     920: Unexpected response.  The MediaWiki site returned something unexpected.
#     921: Unexpected logout.  The MediaWiki site logged us out unexpectedly.
#     922: Edit conflict.  Someone edited the article while we were.
#     923: Deleted article conflict.  Someone deleted the article while we were editing.

package Pearle;

use strict;
use warnings;

use Time::HiRes;

use utf8;

use LWP::UserAgent;
use HTTP::Cookies;
use HTTP::Request::Common qw(POST);
use HTML::Entities;

# Standard regex parts
$Pearle::regex_timestamp = '(\d\d):(\d\d), (\d\d?) (\w+) (\d\d\d\d)';                           # Match and capture a Wikipedia timestamp
$Pearle::regex_timestamp_nc = '\d\d:\d\d, \d\d? \w+ \d\d\d\d';                                          # Match a Wikipedia timestamp

#<a href="/w/index.php?title=User:Angel_dunn&action=edit" class="new" title="User:Angel dunn">
#<a href="/wiki/User:Jimbo_Wales" title="User:Jimbo Wales">
$Pearle::regex_pagelink = '<a href="[^"]*"(?: class="new"|) title="([^"]*)">';    # Match and capture any page
$Pearle::regex_redpagelink = '<a href="[^"]*" class="new" title="([^"]*)">';      # Match and capture nonexistant pages only
$Pearle::regex_bluepagelink = '<a href="[^"]*" title="([^"]*)">';                           # Match and capture existing pages only
$Pearle::regex_pagelink_nc = '<a href="[^"]*"(?: class="new"|) title="[^"]*">';   # Match any page
$Pearle::regex_redpagelink_nc = '<a href="[^"]*" class="new" title="[^"]*">';     # Match nonexistant pages only
$Pearle::regex_bluepagelink_nc = '<a href="[^"]*" title="[^"]*">';                          # Match existing pages only

# Standard MediaWiki namespaces
@Pearle::namespaces = ("", "Talk", "User", "User talk", "Wikipedia", "Wikipedia talk", "Image", "Image talk", "MediaWiki", "MediaWiki talk", "Template", "Template talk", "Help", "Help talk", "Category", "Category talk");

$Pearle::logfile = "";
$Pearle::_inited = 0;
$Pearle::username = "";
$Pearle::password = "";
$Pearle::speedLimit = 10;       # Seconds to wait by default when limit() is called
$Pearle::_speedMult = 1;        # Multiplier for default wait time if the wiki is being slow
$Pearle::roughMode = 0;         # Ignore most errors
$Pearle::nullOK = 0;            # Permit editing non-existent pages
$Pearle::sanityCheck = 0;       # Sanity checking on edits
$Pearle::silent = 0;            # Silent mode
$Pearle::quiet = 0;                     # Quiet mode
$Pearle::logoutOK = 0;          # Permit editing while logged out
$Pearle::proxy = undef;         # Proxy to use

# This must be the first function from the library called
sub init
{
        $Pearle::username = $_[0] or die("902 No username provided!\n");
        $Pearle::password = $_[1] or die("902 No password provided!\n");
        $Pearle::logfile = $_[2] or die("902 No logfile name provided!\n");
        $Pearle::cookies = $_[3] or die("902 No cookie file provided!\n");
        $Pearle::useragent = $_[4] or $Pearle::useragent = "PearleLib/0.2";
        

        $Pearle::ua = LWP::UserAgent->new(timeout => 300);
        $Pearle::ua->agent($Pearle::useragent);
        $Pearle::ua->cookie_jar(HTTP::Cookies->new(file => $Pearle::cookies, autosave => 1));
        $Pearle::ua->cookie_jar->load();

        $Pearle::roughMode = "no";

        # Hot pipes
        $| = 1;
        
        $Pearle::_inited = 1;
}

sub config
{
        my %params = @_;
        $Pearle::speedLimit = $params{speedLimit} if(defined($params{speedLimit}));
        $Pearle::roughMode = $params{roughMode} if(defined($params{roughMode}));
        $Pearle::nullOK = $params{nullOK} if(defined($params{nullOK}));
        $Pearle::silent = $params{silent} if(defined($params{silent}));
        $Pearle::quiet = $params{quiet} if(defined($params{quiet}));
        $Pearle::logfile = $params{logfile} if(defined($params{logfile}));
        $Pearle::logoutOK = $params{logoutOK} if(defined($params{logoutOK}));
        $Pearle::sanityCheck = $params{sanityCheck} if(defined($params{sanityCheck}));
        
        if(exists($params{proxy}))
        {
                if(defined($params{proxy}))
                {
                        myPrint("Proxying: $params{proxy}\n");
                        myLog("Proxying: $params{proxy}\n");
                        $Pearle::ua->proxy('http', $params{proxy});
                        $Pearle::proxy = $params{proxy};
                }
                else
                {
                        myPrint("Not proxying\n");
                        myLog("Not proxying\n");
                        $Pearle::ua->no_proxy();
                        $Pearle::proxy = undef;
                }
        }
}

sub myLog
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

    open (LOG, ">>", $Pearle::logfile) 
        || die "900 Could not append to log!";
    print LOG $_[0];
    close (LOG);
}

sub myPrint
{
        return if($Pearle::silent);
        return if($Pearle::quiet);
        
        print @_;
}

sub myErrPrint
{
        return if($Pearle::silent);
        return if($Pearle::quiet);
        
        print STDERR @_;
}

# Rate-limiting.  Can be sensibly run even if libPearle isn't initialized
sub limit
{
        my ($i);
        $i = ($_[0] or ($Pearle::speedLimit * $Pearle::_speedMult));
        $i = 10 if($i < 10);

        # Rate-limiting to avoid hosing the wiki server
        # Min 30 sec unmarked
        # Min 10 sec marked
        # May be raised by retry() if load is heavy

        ### ATTENTION ###
        # Increasing the speed of the bot to faster than 1 edit every 10
        # seconds violates English Wikipedia rules as of April, 2005, and
        # will cause your bot to be banned.  So don't change $normalDelay
        # unless you know what you are doing.  Other sites may have
        # similar policies, and you are advised to check before using your
        # bot at the default speed.
        #################

        while ($i >= 0)
        {
                sleep (1);
                myErrPrint("Sleeping $i seconds...\r");
                $i--;
        }
        myErrPrint("                                   \r");
}

sub login 
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my $res = $Pearle::ua->post(
                "http://en.wikipedia.org/w/wiki.phtml?title=Special:Userlogin&action=submitlogin",
                Content => [
                        wpName         => $Pearle::username,
                        wpPassword     => $Pearle::password,
                        wpRemember     => 1,
                        wpLoginAttempt => 1
                ]
        );

        if( 302 == $res->code )
        {
                myPrint("Logged in as $Pearle::username\n");
                myLog("Logged in as $Pearle::username\n");
                # This may or may not actually work
                $Pearle::ua->cookie_jar->save();
                return 1;
        }
        else
        {
                myPrint("Login failed\n");
                myPrint("Code: ".$res->code."\n");
                myLog("Login failed\n");
                return 0;
        }
}

sub logout {
        my $res = $Pearle::ua->post(
                "http://en.wikipedia.org/w/wiki.phtml?title=Special:Userlogout",
        );

        return 1;
}

sub checkLogin
{
        my ($reply_text);
        $reply_text = $_[0];
        
        if ($reply_text !~ m/>My talk<\/a>/ and !($Pearle::logoutOK))
        {
                # We've lost our identity.
                myLog ("Wiki server is not recognizing me.\n");
                die ("921 Wiki server is not recognizing me.\n");
        }
}

# Make an HTTP request, performing basic error checking and handling.  Suitable for use with the "retry" function
sub httpRequest
{
        my ($request, $response, $attemptStartTime, $attemptEndTime);
        $request = $_[0];
        
        # Since not every server handles UTF-8 in URLs, and LWP doesn't escape them properly, escape every character > 255
        $request->uri(unicodeToUrl($request->uri()));
        
        $response = $Pearle::ua->request($request);

        # Monitor wiki server responsiveness
        $attemptStartTime = Time::HiRes::time();

        if ($response->is_success or $response->is_redirect)
        {
                return $response
        } 
        else 
        {
                myLog ("HTTP ERR (".$response->status_line.")\n".$response->content."\n");
                myPrint("HTTP ERR (".$response->status_line.")\n".$response->content."\n");
                # 50X HTTP errors mean there is a problem connecting to the wiki server.  Can be remedied by waiting and trying again
                if (500 <= $response->code and 504 >= $response->code)
                {
                        die("retry:".$response->status_line);
                }
                else
                {
                        # Unhandled HTTP response.  Waiting probably won't fix it
                        die ($response->status_line."\n");
                }
        }
        # Monitor wiki server responsiveness
        $attemptEndTime = Time::HiRes::time();

        if($request->method() eq "POST")
        {
                if (($attemptEndTime - $attemptStartTime) > 20)
                {
                        $Pearle::_speedMult = 60;

                        myPrint("Wikipedia is very slow.  Increasing minimum wait to " . $Pearle::speedLimit * $Pearle::_speedMult . " sec...\n");
                        myLog("Wikipedia is very slow.  Increasing minimum wait to " . $Pearle::speedLimit * $Pearle::_speedMult . " sec...\n");
                }

                # If the response time is between 10 and 20 seconds...
                elsif (($attemptEndTime - $attemptStartTime) > 10)
                {
                        $Pearle::_speedMult = 6;

                        myPrint("Wikipedia is somewhat slow.  Setting minimum wait to " . $Pearle::speedLimit * $Pearle::_speedMult . " sec...\n");
                        myLog("Wikipedia is somewhat slow.  Setting minimum wait to " . $Pearle::speedLimit * $Pearle::_speedMult . " sec...\n");
                }

                # If the response time is less than 10 seconds...
                else
                {
                        if ($Pearle::_speedMult != 1)
                        {
                                $Pearle::_speedMult = 1;

                                myPrint( "Returning to normal minimum wait time.\n");
                                myLog("Returning to normal minimum wait time.\n");
                        }
                }
        }
}

# Check out a page for editing.
sub getPage
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($target, $request, $response, $reply, $text, $text2,
        $editTime, $startTime, $attemptStartTime, $attemptFinishTime,
        $token, $targetSafe);

        $target = $_[0];

        if ($target =~ m/^\s*$/)
        {
                myLog("getPage: Null target.");
                die("902 getPage: Null target.");
        }

        $targetSafe = $target;
        $targetSafe =~ s/\&/%26/g;
        $targetSafe =~ s/\+/%2B/g;

        # Create a request-object
        myPrint("GET http://en.wikipedia.org/w/wiki.phtml?title=${targetSafe}&action=edit\n");
        myLog("GET http://en.wikipedia.org/w/wiki.phtml?title=${targetSafe}&action=edit\n");
        $request = HTTP::Request->new(GET => "http://en.wikipedia.org/w/wiki.phtml?title=${targetSafe}&action=edit");
        $response = startRetry(\&httpRequest, $request);

        $reply = $response->content;

        # This detects whether or not we're logged in.
        checkLogin($reply);

        # Check for blocking
        if($reply =~ /<h1 class="firstHeading">User is blocked<\/h1>/)
        {
                myLog("Blocked\n");
                die("900 Blocked");
        }
        
        $reply =~ m%<textarea\s+tabindex='1'\s+accesskey=","\s+name="wpTextbox1"\s+id="wpTextbox1"\s+rows='25'\s+cols='80'\s+>(.*?)</textarea>%s;
        $text = $1;

        $reply =~ m/value="(\d+)" name="wpEdittime"/;
        $editTime = $1;

        # Added 22 Aug 2005 to correctly handle articles that have
        # been undeleted
        $reply =~ m/value="(\d+)" name="wpStarttime"/;
        $startTime = $1;

        # Added 9 Mar 2005 after recent software change.
        $reply =~ m/value="([^"]+)" name="wpEditToken"/;
        $token = $1;
        ###

        if (($text =~ m/^\s*$/) and !$Pearle::nullOK)
        {
                myLog ("getPage($target): Null text!\n");
                myLog ("\n---\n$reply\n---\n");
                if ($Pearle::roughMode)
                {
                        return;
                }
                else
                {
                        die ("920 getPage($target): Null text!\n");
                }
        }

        if (($editTime =~ m/^\s*$/) and !$Pearle::nullOK)
        {
                myLog ("getPage($target): Null time!\n");
                myLog("\n---\n$reply\n---\n");
                die ("920 getPage($target): Null time!\n");
        }

        if (($text =~ m/>/) or ($text =~ m/</))
        {
                myPrint($text);
                myLog("\n---\n$text\n---\n");
                myLog ("getPage($target): Bad text suck!\n");
                die ("920 getPage($target): Bad text suck!\n");
        }

        # Change ( " -> " ) etc
        # This function is from HTML::Entities.
        decode_entities($text);

        # This may or may not actually work
        $Pearle::ua->cookie_jar->save();

        return ($text, $editTime, $startTime, $token);
}


sub postPage
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($request, $response, $pageName, $textToPost, $summaryEntry,
        $editTime, $startTime, $actual, $expected, $date, $editToken,
        $minor, $pageNameSafe);

        $pageName = $_[0];
        $editTime = $_[1];
        $startTime = $_[2];
        $editToken = $_[3];
        $textToPost = $_[4];
        $summaryEntry = $_[5]; # Max 200 chars!
        $minor = $_[6];

        $summaryEntry = substr($summaryEntry, 0, 200);

        if ($pageName eq "")
        {
                myLog ("postPage(): Empty pageName.\n"); 
                die ("902 postPage(): Empty pageName.\n"); 
        }
        
        if(!defined($minor))
        {
                die "902 postPage(): Not enough parameters!\n";
        }

        if ($summaryEntry eq "")
        {
                $summaryEntry = "Automated editing.";
        }

        $pageNameSafe = $pageName;
        $pageNameSafe =~ s/\&/%26/g;
        $pageNameSafe =~ s/\+/%2B/g;

        if ($minor eq "yes")
        {
                $request = POST "http://en.wikipedia.org/w/wiki.phtml?title=${pageNameSafe}&action=submit",
                [wpTextbox1 => $textToPost,
                wpSummary => $summaryEntry,
                wpSave => "Save page",
                wpMinoredit => "on",
                wpEditToken => $editToken,
                wpStarttime => $startTime,
                wpEdittime => $editTime];
                # Optional: wpWatchthis
        }
        else
        {
                $request = POST "http://en.wikipedia.org/w/wiki.phtml?title=${pageNameSafe}&action=submit",
                [wpTextbox1 => $textToPost,
                wpSummary => $summaryEntry,
                wpSave => "Save page",
                wpEditToken => $editToken,
                wpStarttime => $startTime,
                wpEdittime => $editTime];
                # Optional: wpWatchthis, wpMinoredit
        }

        # ---
        ## If posts are failing, you can uncomment the below to see what
        ## HTTP request is being made.
        # myLog($request->as_string());
        # print $request->as_string();       $::speedLimit = 60 * 10;
        # print $::ua->request($request)->as_string;
        # ---

        myLog("POSTing...");
        myPrint("POSTing...");
        # Pass request to the user agent and get a response back
        $response = startRetry(\&httpRequest, $request);
        myLog("POSTed.\n");
        myPrint("POSTed.\n");


        if ($response->content =~ m/Please confirm that really want to recreate this article./)
        {
                myLog ($response->content."\n");
                die ("923 Deleted article conflict! See log!");
        }


        # Check the outcome of the response
        $response->code;
        if ($response->code != 302 and $response->code  != 200)
        {
                myLog ("postPage(${pageName}, $editTime)#1 - expected =! actual\n");
                myLog ($request->as_string());
                myLog ("EXPECTED: 302'\n");
                myLog ("  ACTUAL: '" . $response->status_line . "'\n");

                if ($Pearle::roughMode eq "yes")
                {
                        return();
                }
                else
                {
                        die ("920 postPage(${pageName}, $editTime)#1 - expected =! actual - see log\n");
                }
        }

        $expected = "http://en.wikipedia.org/wiki/${pageName}";
        $expected = Pearle::urlEncode($expected);

        $actual = $response->headers->header("Location");


        if (($expected ne $actual) and ($Pearle::roughMode ne "yes") 
            and !(($actual eq "") and ($response->code == 200)))
        {
                myLog ("postPage(${pageName}, $editTime)#2 - expected =! actual\n");
                myLog ("EXPECTED: '${expected}'\n");
                myLog ("  ACTUAL: '${actual}'\n");
                die ("920 postPage(${pageName}, $editTime)#2 - expected =! actual - see log\n");
        }


        if ($response->content =~ m/<h1 class="firstHeading">Edit conflict/)
        {
                myLog ("Edit conflict on '$pageName' at '$editTime'!\n");
                die ("922 Edit conflict on '$pageName' at '$editTime'!\n");
        }
        
        if($Pearle::sanityCheck and $pageName =~ /talk[ _]*:/i) # Check for accidental creation of a talkpage without a mainpage.  Only works with bots using the "monobook" skin.
        {
                # Monobook:<li id="ca-nstab-main" class="new"><a href="/w/index.php?title=Kjsahfjrf&action=edit">Article</a></li> 
                # Classic: <br /><a href="/w/index.php?title=Kjsahfjrf&action=edit" class="new" title="Kjsahfjrf">View article</a>
                if($response->content =~ /<li id="ca-nstab-[^"]" class="new">/)
                {
                        myLog ("postPage(${pageName}) - Talkpage without article!\n");
                        die ("920 postPage(${pageName}) - Talkpage without article!\n");
                }
        }
        
        if($Pearle::sanityCheck and $pageName =~ /^user[ _]*talk[ _]*:/)        # Check for user talkpage for non-existant user
        {
                if($response->content !~ /User contributions/)
                {
                        myLog ("postPge(${pageName}) - User talkpage for non-existant user!\n");
                        die ("920 postPge(${pageName}) - User talkpage for non-existant user!\n");
                }
        }

        $Pearle::ua->cookie_jar->save();
        return ($response->content);
}


# Get a list of the names of articles in a given category.
sub getCategoryArticles
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($target, $request, $response, $reply, $articles, $article,
        @articles,      $targetSpace, $offset, $numberOfArticles, $url,
        @moreArticles);


        $target = $_[0];
        $offset = $_[1];

        # Need both _ and spaces for precise matching later
        $target =~ s/ /_/g;
        $targetSpace = $target;
        $targetSpace =~ s/_/ /g;

        unless ($target =~ m/^Category:/)
        {
                myLog ("getCategoryArticles(): Are you sure '$target' is a category?\n");
                die ("902 getCategoryArticles(): Are you sure '$target' is a category?\n");
        }

        if ($offset eq "")
        {
                $url = "http://en.wikipedia.org/wiki/${target}";
        }
        else
        {
                $url = "http://en.wikipedia.org/w/index.php?title=${target}&from=${offset}";
        }

        # Create a request-object
        if ($offset eq "")
        {
                myPrint("GET ${url}\n");
        }
        myLog("GET ${url}\n");
        $request = HTTP::Request->new(GET => "${url}");
        $response = startRetry(\&httpRequest, $request);

        $reply = $response->content;

        # This detects whether or not we're logged in.
        checkLogin($reply);

        $articles = $reply;
        $articles =~ s%^.*?<h2>Articles in category.*?</h2>%%s;
        $articles =~ s%<div class="printfooter">.*?$%%s;
        @articles = $articles =~ m%<li><a href="/wiki/(.*?)" title=%sg;

        if ($reply =~ m/<a\s+href=\"\/w\/index.php\?title=${target}\&from=(.*?)\"\s+title=\"${targetSpace}\">next 200<\/a>/s)
        {
                sleep (1); # Throttle GETs
                @moreArticles = getCategoryArticles($target, $1);
                @articles = (@articles, @moreArticles);
        }

        $Pearle::ua->cookie_jar->save();

        $numberOfArticles = @articles;

        if ($offset eq "")
        {
                myPrint("Got $numberOfArticles articles.\n");
                myLog ("Got $numberOfArticles articles.\n");
        }
        return decodeArray(@articles);
}

sub getCategoryImages
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($target, $from, $request, $response, $reply, $images, @images,
        $image, %imagesHash);


        $target = $_[0];
        $from = $_[1];

        unless ($target =~ m/^Category:/)
        {
                myLog ("getCategoryImages(): Are you sure '$target' is a category?\n");
                die ("902 getCategoryImages(): Are you sure '$target' is a category?\n");
        }

        # Create a request-object
        if(!defined($from))     # Default: Start at the beginning of a category
        {
                myPrint("GET http://en.wikipedia.org/wiki/${target}\n");
                myLog("GET http://en.wikipedia.org/wiki/${target}\n");
                $request = HTTP::Request->new(GET => "http://en.wikipedia.org/wiki/${target}");
        }
        else    # Start somewhere middle-ish
        {
                myPrint("GET http://en.wikipedia.org/w/wiki.phtml?title=${target}&from=$from\n");
                myLog("GET http://en.wikipedia.org/w/wiki.phtml?title=${target}&from=$from\n");
                $request = HTTP::Request->new(GET => "http://en.wikipedia.org/w/wiki.phtml?title=${target}\&from=$from");
        }
        $response = startRetry(\&httpRequest, $request);
        $reply = $response->content;

        # This detects whether or not we're logged in.
        checkLogin($reply);
#       unless ($reply =~ m%<a href="/wiki/User_talk:$Pearle::username">My talk</a>%)
#       {
#               # We've lost our identity.
#               myLog ("Wiki server is not recognizing me (2).\n---\n${reply}\n---\n");
#               die ("Wiki server is not recognizing me (2).\n");
#       }

        $images = $reply;
        $images =~ s/^.*?<table class="gallery"//s;
        $images =~ s/<div class="printfooter">.*?$//s;
        @images = $images =~ m/<a\s+href="\/wiki\/(.*?)"\s+title=\"Image:/g;

        @images = grep {$_ =~ /^Image:/} @images;

        if($images =~ /&from=([^"]+)" title="Category:[^"]*">next 200/)
        {
                print "More: $1\n";
                @images = (@images, getCategoryImages($target, $1));
        }

        # Uniqify to prevent duplicates
        @images = uniquify(@images);

        $Pearle::ua->cookie_jar->save();
        return decodeArray(@images);
}



sub getSubcategories
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($target, $request, $response, $reply, $subcats, $subcat,
        @subcats, $attemptStartTime, $attemptFinishTime);

        $target = $_[0];

        unless ($target =~ m/^Category:/)
        {
                myLog ("getSubcategories(): Are you sure '$target' is a category?\n");
                die ("902 getSubcategories(): Are you sure '$target' is a category?\n");
        }

        # Create a request-object
        myPrint("GET http://en.wikipedia.org/wiki/${target}\n");
        myLog("GET http://en.wikipedia.org/wiki/${target}\n");
        $request = HTTP::Request->new(GET => "http://en.wikipedia.org/wiki/${target}");
        $response = startRetry(\&httpRequest, $request);
        $reply = $response->content;

        # This detects whether or not we're logged in.
        checkLogin($reply);

        $subcats = $reply;

        if ($subcats =~ m%^.*?<h2>Subcategories</h2>(.*?)<h2>Pages in category.*?</h2>.*?$%s)
        {
                $subcats =~ s%^.*?<h2>Subcategories</h2>(.*?)<h2>Pages in category.*?</h2>.*?$%$1%s;
        }
        else
        {
                return ();
        }

        @subcats = $subcats =~ m%<li><a href="/wiki/(.*?)" title=%sg;

        $Pearle::ua->cookie_jar->save();
        return decodeArray(@subcats);
}

# Get up to $max most recent articles edited by a user
sub getUserArticles
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($url, $request, $response, $reply, @contribs,
            $target, $namespace, $max, $offset);
        
        $target = $_[0];
        $max = $_[1];
        $offset = $_[2];
        $namespace = namespaceToNumber($_[3]);

        # Create a request-object
        if(defined($namespace))
        {
                $url = "http://en.wikipedia.org/w/index.php?title=Special%3AContributions&limit=${max}&offset=${offset}&target=${target}&namespace=$namespace";
        }
        else
        {
                $url = "http://en.wikipedia.org/w/index.php?title=Special%3AContributions&limit=${max}&offset=${offset}&target=${target}";
        }

        myPrint("GET $url\n");
        myLog("GET $url\n");
        $request = HTTP::Request->new(GET => "$url");
        $response = startRetry(\&httpRequest, $request);
        $reply = $response->content;

        # This detects whether or not we're logged in.
        checkLogin($reply);
                
        # Extract the contributions
        # <li>23:18, 6 March 2006 (<a href="/w/index.php?title=User_talk:OrphanBot&action=history" title="User talk:OrphanBot">
        while($reply =~ /<li>$Pearle::regex_timestamp_nc \($Pearle::regex_bluepagelink/g)
        {
                push @contribs, $1;
        }
        
        # Remove duplicates     
#       @contribs = uniquify(@contribs);
        return @contribs;
}

# Gets a list of (articles, actor, summary) tuples from the specified log (upload, delete, move, protect)
sub getLogArticles
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($url, $request, $response, $reply, @articles,
            $log, $max, $offset, $user);
        
        
        $log = $_[0];
        $max = $_[1] || 50;
        $offset = $_[2] || 0;
        $user = $_[3] || '';

        # Create a request-object
        # http://en.wikipedia.org/w/index.php?title=Special:Log&type=upload&user=&page=&limit=2000&offset=0
        $url = "http://en.wikipedia.org/w/index.php?title=Special%3ALog&limit=${max}&offset=${offset}&user=${user}&type=${log}";

        myPrint("GET $url\n");
        myLog("GET $url\n");
        $request = HTTP::Request->new(GET => "$url");
        $response = startRetry(\&httpRequest, $request);
        $reply = $response->content;

        # This detects whether or not we're logged in.
        checkLogin($reply);
                
        # Extract the articles
        #<li>19:55, 7 March 2006 <a href="/wiki/User:Jimbo_Wales" title="User:Jimbo Wales">Jimbo Wales</a> deleted "<a href="/w/index.php?title=Image:Justinsfriends.jpg&action=edit" class="new" title="Image:Justinsfriends.jpg">Image:Justinsfriends.jpg</a>"  <span class='comment'>(blatant copyvio)</span> </li>
        #<li>19:54, 7 March 2006 <a href="/wiki/User:MrD9" title="User:MrD9">MrD9</a> moved <a href="/w/index.php?title=Statsoft&redirect=no" title="Statsoft">Statsoft</a> to <a href="/wiki/StatSoft" title="StatSoft">StatSoft</a>  (<a href="/w/index.php?title=Special:Movepage&wpOldTitle=StatSoft&wpNewTitle=Statsoft&wpReason=revert&wpMovetalk=0" title="Special:Movepage">revert</a>)</li>
        #<li>19:53, 7 March 2006 <a href="/w/index.php?title=User:Biederman&action=edit" class="new" title="User:Biederman">Biederman</a> uploaded "<a href="/wiki/Image:Rockingham_Raymond_NH.PNG" title="Image:Rockingham Raymond NH.PNG">Image:Rockingham Raymond NH.PNG</a>"  <span class='comment'>(Changed Image:Rockingham_Portsmouth_NH.PNG to highlight Raymond )</span> </li>
        #<li>19:31, 7 March 2006 <a href="/wiki/User:Francs2000" title="User:Francs2000">Francs2000</a> protected <a href="/wiki/Manoeuvre.org" title="Manoeuvre.org">Manoeuvre.org</a>  <span class='comment'>({{deletedpage}} [edit=sysop:move=sysop])</span> </li>
        #<li>19:30, 7 March 2006 <a href="/wiki/User:Tony_Sidaway" title="User:Tony Sidaway">Tony Sidaway</a> unprotected <a href="/wiki/Will_McWhinney" title="Will McWhinney">Will McWhinney</a>  <span class='comment'>(This looks like the protection that time forgot.)</span> </li>


#       while($reply =~ /<li>$Pearle::regex_timestamp_nc ${Pearle::regex_pagelink}.*?<\/a> (?:deleted|moved|uploaded|protected|unprotected) "?${Pearle::regex_pagelink}.*?<\/a>"(?:\s*<span class='comment'>(.*)<\/span>|)/g)
        while($reply =~ /<li>($Pearle::regex_timestamp_nc) ${Pearle::regex_pagelink}.*?<\/a> \(${Pearle::regex_pagelink_nc}Talk<\/a> \| ${Pearle::regex_pagelink_nc}contribs<\/a>\) (?:deleted|moved|uploaded|protected|unprotected) "?${Pearle::regex_pagelink}.*?<\/a>"(?:\s*<span class="comment">(.*)<\/span>|)/g)
        {
                my $summary = $3 || '';
                push @articles, [$3, $2, $summary, $1];
        }
        @articles = uniquify_ref1(@articles);
        return @articles;
}

# Use the Special:Export interface to get the wikitext of one or more articles
sub Export
{
        my ($request, $response, $reply, $articles);
        
        $articles = join "\n", @_;
        
        $request = POST "http://en.wikipedia.org/w/index.php?title=Special:Export&action=submit", [action => 'submit', pages => $articles, curonly => 1];
        $response = startRetry(\&httpRequest, $request);
        $reply = $response->content;

        return $reply;
}

# Do a null edit to an article
sub nullEdit
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);

        my ($text, $articleName, $comment, $editTime, $startTime, $token);

        $articleName = $_[0];

        myPrint("nullEdit($articleName)\n");
        myLog ("nullEdit($articleName)\n");

        ($text, $editTime, $startTime, $token) = getPage($articleName);
        unless ($text eq "")
        {
                postPage ($articleName, $editTime, $startTime, $token, $text, "null edit");
        }
}

# Get the history of an article and parse the first 500 entries into a list of [link day month year] lists
sub parseHistory
{
    my ($pageName, $html, @lines, $line, $date, $hour, $minute, $day, $month, $year,
        $htmlCopy, $link, $user, @result);

    $pageName = $_[0];
        $pageName = escapeUrl($pageName);
        
    $html = getURL("http://en.wikipedia.org/w/index.php?title=${pageName}&action=history&limit=500");

    $htmlCopy = $html;

    $html =~ s%^.*?<ul id="pagehistory">%%s;
    $html =~ s%(.*?)</ul>.*$%$1%s;

    @lines = split ("</li>", $html);
    foreach $line (@lines)
    {
                $line =~ s/\n/ /g;

                if ($line =~ m/^\s*$/)
                {
                next;
                }
                ($user) = $line =~ /<span class='history-user'><a href=[^>]*>([^<]*)/;
                $line =~ s/<span class='history-user'>.*?$//;
                $line =~ s/^.*?Select a newer version for comparison//;
                $line =~ s/^.*?Select a older version for comparison//;
                $line =~ s/^.*?name="diff" \/>//;
                
                $line =~ m%<a href="(.*?)" title="(.*?)">$Pearle::regex_timestamp</a>%;
                $link = $1;
                $hour = $3;
                $minute = $4;
                $day = $5;
                $month = $6;
                $year = $7;

                push @result, [$link, $day, $month, $year, $user];
    }
    
    return (@result);
}


sub getURL #($target)
{
        die "901 Pearle library not initialized!\n" if(!$Pearle::_inited);
    # Read throttle!
    sleep (1);

    my ($request, $response, $reply, $url);
    
    $url = $_[0];

    # Create a request-object
    myPrint("GET ${url}\n");
    myLog("GET ${url}\n");
    $request = HTTP::Request->new(GET => "${url}");
    $response = startRetry(\&httpRequest, $request);

        $reply = $response->content;
        
        # This may or may not actually work
        $Pearle::ua->cookie_jar->save();

        return ($reply);
}


# Retries a given function repeatedly, with an exponential backoff rate
# The function should throw an exception beginning with "retry:" (case insensitive) if the call should be retried
sub startRetry
{
        my ($call_fn, @args) = @_;
        return retry($Pearle::speedLimit, $call_fn, @args);
}

sub retry
{
        my ($call_fn, @args, $delay, @result, $result);
        
        ($delay, $call_fn, @args) = @_;
        
        if(wantarray())
        {
                @result = eval{ $call_fn->(@args) };
                if($@ =~ /^retry:/i)
                {
                        limit($delay);
                        @result = retry($delay * 2, $call_fn, @args);
                }
                elsif($@)
                {
                        die;
                }
                return @result;
        }
        else
        {
                $result = eval{ &{$call_fn}(@args) };
                if($@ =~ /^retry:/i)
                {
                        limit($delay);
                        $result = retry($delay * 2, $call_fn, @args);
                }
                elsif($@)
                {
                        die;
                }
                return $result;
        }
}


sub namespaceToNumber
{
        my $namespace = $_[0];
        my $i = 0;
        my $name;
        if(defined($namespace))
        {
                foreach $name (@Pearle::namespaces)
                {
                        return $i if(lc($name) eq lc($namespace));
                        $i++;
                }
        }
        else
        {
                return undef;
        }
}

sub numberToNamespace
{
        my $i = shift;
        if(defined($i))
        {
                return $Pearle::namespaces[$i];
        }
        else
        {
                return undef;
        }
}


# Translate from HTTP URL encoding to the native character set.
sub urlDecode
{
        my ($input);

        $input = $_[0];

        $input =~ s/\%([a-f|A-F|0-9][a-f|A-F|0-9])/chr(hex($1))/eg;

        return ($input);
}

# Basic escaping of special characters in a URL
sub escapeUrl
{
        my $input = shift;
        $input =~ s/%/%25/g;
        $input =~ s/&/%26/g;
        
        $input = unicodeToUrl($input);
        
        return $input;
}

# URL-escape any high-unicode chars in a string
sub unicodeToUrl
{
        my ($char, $input, $output);;
        
        $input = $_[0];

        foreach $char (split("",$input))
        {
                if(ord($char) > 255)
                {
                        $output .= uc(sprintf("%%%x%%%x", int(ord($char)/256), ord($char) & 0xFF));
                        # %HH%LL where HHLL is the hex code of $char
                }
                else
                {
                        $output .= $char;
                }
        }
        return $output;
}

# Translate from the native character set to the Wikipedia HTTP URL encoding.
sub urlEncode
{
        my ($char, $input, $output);

        $input = $_[0];

        foreach $char (split("",$input))
        {
                #       if ($char =~ m/[a-z|A-Z|0-9|\-_\.\!\~\*\'\(\)]/)

                # The below exclusions should conform to Wikipedia practice
                # (possibly non-standard)
                if ($char =~ m/[a-z|A-Z|0-9|\-_\.\/:]/)
                {
                        $output .= $char;
                }
                elsif ($char eq " ")
                {
                        $output .= "_";
                }
                else
                {
                        if(ord($char) > 255)
                        {
                                $output .= uc(sprintf("%%%x%%%x", int(ord($char)/256), ord($char) & 0xFF));
                                # %HH%LL where HHLL is the hex code of $char
                        }
                        else
                        {
                                $output .= uc(sprintf("%%%x", ord($char)));
                                # %HH where HH is the hex code of $char
                        }
                }
        }

        return ($output);
}

sub decodeArray
{
        return map {urlDecode($_)} @_;
}

# Remove duplicates from a list
sub uniquify
{
        my @list = @_;
        @list = sort @list;
        my $last = undef;
        my @new_list;
        my $item;
        
        foreach $item (@list)
        {
                push @new_list, $item if(!defined($last) or ($item ne $last));
                $last = $item;
        }
        return @new_list;
}

# Remove duplicates from a list of array references, grouping on the first subelement
sub uniquify_ref1
{
        my @list = @_;
        @list = sort {$a->[0] cmp $b->[0]} @list;
        my $last = undef;
        my @new_list;
        my $item;

        foreach $item (@list)
        {
                push @new_list, $item if(!defined($last) or ($item->[0] ne $last));
                $last = $item->[0];
        }
        return @new_list;
}

1;