Update It's Walky ripper to work like DoA

Fixes #4

itswalky.php

@@ -1,57 +1,56 @@
 <?php
 // It's Walky
-// This one has directory indexes! Yay!
+// Based on the Dumbing of Age script
 
-// We basically just read the directories and filter out the thumbnails
-// This is actually generalized enough it could easily fit most WP sites
+// We start with the current day, then click the Previous link until we find
+// an image we've already saved before.
 
-// If running multiple times per day, the $years and $months can be changed
-// to only contain the current year/month
+$html = file_get_contents('http://www.itswalky.com/');
+preg_match('@img src="http://www.itswalky.com/wp-content/uploads/(.+\\.png)@', $html, $matches);
 
-$base = 'http://www.itswalky.com/wp-content/uploads/';
-$years = range(2012, date('Y'));
-$months = [1,12];
+if (empty($matches[1])) {
+    echo "No comic found on home page! :(\n";
+    return;
+}
 
 if (!is_dir('itswalky')) {
     mkdir('itswalky');
 }
 
-foreach ($years as $y) {
-    foreach ($months as $m) {
-        // Skip known nonexistent months
-        if ($y == 2012 && $m < 8) {
-            continue;
-        }
-
-        $dir = $base . sprintf('%d/%02d/', $y, $m);
-        $html = file_get_contents($dir);
-
-        preg_match_all('@<a href="([^/"]+)">@', $html, $matches);
-        foreach ($matches[1] as $file) {
-            // Remove thumbnails
-            if (preg_match('/-[0-9]+x[0-9]+\\.(png|gif)$/', $file)) {
-                continue;
-            }
-
-            // Remove non-comics for now
-            if (!preg_match('/^[0-9]{4}/', $file)) {
-                continue;
-            }
-
-            // Skip already downloaded images
-            if (is_file("itswalky/$file")) {
-                continue;
-            }
-
-            // Download image
-            echo "Downloading $file\n";
-            $url = $dir . $file;
-            $data = @file_get_contents($url);
-            if ($data) {
-                file_put_contents("itswalky/$file", $data);
-            }
-
-            usleep(5e5);
-        }
+// Download current page's comic, load previous comic webpage, repeat
+while (true) {
+    $filename = basename($matches[1]);
+    if (is_file('itswalky/' . $filename)) {
+        return;
+    }
+
+    echo "Downloading {$filename}\n";
+    $url = "http://www.itswalky.com/wp-content/uploads/{$matches[1]}";
+    $data = @file_get_contents($url);
+    if ($data) {
+        file_put_contents("itswalky/{$filename}", $data);
+    }
+
+    // Find previous page link
+    $regex = '@href="(http://www.itswalky.com/comic/[0-9a-zA-Z/-]+)" class="comic-nav-base comic-nav-previous"@';
+    preg_match($regex, $html, $prevMatch);
+
+    if (empty($prevMatch[1])) {
+        echo "No previous URL found!\n";
+        return;
     }
+
+    $html = @file_get_contents($prevMatch[1]);
+    if (!$html) {
+        echo "Failed to load previous page!\n";
+        return;
+    }
+
+    preg_match('@img src="http://www.itswalky.com/wp-content/uploads/(.+\\.png)@', $html, $matches);
+    if (empty($matches[1])) {
+        echo "No image found on page!\n";
+        return;
+    }
+
+    usleep(5e5);
 }