Added new ripper for http://nhentai.net/

src/main/java/com/rarchives/ripme/ripper/rippers/NhentaiRipper.java

@@ -0,0 +1,171 @@
+package com.rarchives.ripme.ripper.rippers;
+
+import com.rarchives.ripme.ripper.AbstractHTMLRipper;
+import com.rarchives.ripme.ripper.DownloadThreadPool;
+import com.rarchives.ripme.utils.Http;
+import com.rarchives.ripme.utils.Utils;
+import org.jsoup.nodes.Document;
+import org.jsoup.nodes.Element;
+import org.jsoup.select.Elements;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class NhentaiRipper extends AbstractHTMLRipper {
+
+    // All sleep times are in milliseconds
+    private static final int IMAGE_SLEEP_TIME = 1500;
+
+    private String albumTitle;
+    private Document firstPage;
+
+    // Thread pool for finding direct image links from "image" pages (html)
+    private DownloadThreadPool nhentaiThreadPool = new DownloadThreadPool("nhentai");
+
+    @Override
+    public DownloadThreadPool getThreadPool() {
+        return nhentaiThreadPool;
+    }
+
+    public NhentaiRipper(URL url) throws IOException {
+        super(url);
+    }
+
+    @Override
+    public String getDomain() {
+        return "nhentai.net";
+    }
+
+    @Override
+    public String getHost() {
+        return "nhentai";
+    }
+
+    @Override
+    public String getAlbumTitle(URL url) throws MalformedURLException {
+        if (firstPage == null) {
+            try {
+                firstPage = Http.url(url).get();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+
+        String title = firstPage.select("#info > h1").text();
+        if (title == null) {
+            return getAlbumTitle(url);
+        }
+        return title;
+    }
+
+    @Override
+    public String getGID(URL url) throws MalformedURLException {
+        // Ex: https://nhentai.net/g/159174/
+        Pattern p = Pattern.compile("^https?://nhentai\\.net/g/(\\d+).*$");
+        Matcher m = p.matcher(url.toExternalForm());
+        if (m.matches()) {
+            // Return the text contained between () in the regex - 159174 in this case
+            return m.group(1);
+        }
+        throw new MalformedURLException("Expected nhentai.net URL format: " +
+                "nhentai.net/g/albumid - got " + url + " instead");
+    }
+
+    @Override
+    public Document getFirstPage() throws IOException {
+        if (firstPage == null) {
+            firstPage = Http.url(url).get();
+        }
+        return firstPage;
+    }
+
+    @Override
+    public List<String> getURLsFromPage(Document page) {
+        List<String> imageURLs = new ArrayList<String>();
+        Elements thumbs = page.select(".gallerythumb");
+        for (Element el : thumbs) {
+            String imageUrl = el.attr("href");
+            imageURLs.add("https://nhentai.net" + imageUrl);
+        }
+        return imageURLs;
+    }
+
+    @Override
+    public void downloadURL(URL url, int index) {
+        NHentaiImageThread t = new NHentaiImageThread(url, index, this.workingDir);
+        nhentaiThreadPool.addThread(t);
+        try {
+            Thread.sleep(IMAGE_SLEEP_TIME);
+        } catch (InterruptedException e) {
+            logger.warn("Interrupted while waiting to load next image", e);
+        }
+    }
+
+    private class NHentaiImageThread extends Thread {
+
+        private URL url;
+        private int index;
+        private File workingDir;
+
+        NHentaiImageThread(URL url, int index, File workingDir) {
+            super();
+            this.url = url;
+            this.index = index;
+            this.workingDir = workingDir;
+        }
+
+        @Override
+        public void run() {
+            fetchImage();
+        }
+
+        private void fetchImage() {
+            try {
+                //Document doc = getPageWithRetries(this.url);
+                Document doc = Http.url(this.url).get();
+
+                // Find image
+                Elements images = doc.select("#image-container > a > img");
+                if (images.size() == 0) {
+                    // Attempt to find image elsewise (Issue #41)
+                    images = doc.select("img#img");
+                    if (images.size() == 0) {
+                        logger.warn("Image not found at " + this.url);
+                        return;
+                    }
+                }
+                Element image = images.first();
+                String imgsrc = image.attr("src");
+                logger.info("Found URL " + imgsrc + " via " + images.get(0));
+
+                Pattern p = Pattern.compile("^https?://i.nhentai.net/galleries/\\d+/(.+)$");
+                Matcher m = p.matcher(imgsrc);
+                if (m.matches()) {
+                    // Manually discover filename from URL
+                    String savePath = this.workingDir + File.separator;
+                    if (Utils.getConfigBoolean("download.save_order", true)) {
+                        savePath += String.format("%03d_", index);
+                    }
+                    savePath += m.group(1);
+                    addURLToDownload(new URL(imgsrc), new File(savePath));
+                } else {
+                    // Provide prefix and let the AbstractRipper "guess" the filename
+                    String prefix = "";
+                    if (Utils.getConfigBoolean("download.save_order", true)) {
+                        prefix = String.format("%03d_", index);
+                    }
+                    addURLToDownload(new URL(imgsrc), prefix);
+                }
+            } catch (IOException e) {
+                logger.error("[!] Exception while loading/parsing " + this.url, e);
+            }
+        }
+
+    }
+}