1 package net.pterodactylus.sone.core
3 import com.google.common.base.Ticker
4 import com.google.common.cache.Cache
5 import com.google.common.cache.CacheBuilder
6 import freenet.keys.FreenetURI
7 import java.io.ByteArrayInputStream
8 import java.net.URLDecoder
9 import java.text.Normalizer
10 import java.util.concurrent.TimeUnit.MINUTES
11 import javax.imageio.ImageIO
12 import javax.inject.Inject
15 * [ElementLoader] implementation that uses a simple Guava [com.google.common.cache.Cache].
17 class DefaultElementLoader(private val freenetInterface: FreenetInterface, ticker: Ticker) : ElementLoader {
19 @Inject constructor(freenetInterface: FreenetInterface) : this(freenetInterface, Ticker.systemTicker())
21 private val loadingLinks: Cache<String, Boolean> = CacheBuilder.newBuilder().build<String, Boolean>()
22 private val failureCache: Cache<String, Boolean> = CacheBuilder.newBuilder().ticker(ticker).expireAfterWrite(30, MINUTES).build<String, Boolean>()
23 private val imageCache: Cache<String, LinkedElement> = CacheBuilder.newBuilder().build<String, LinkedElement>()
24 private val callback = object : FreenetInterface.BackgroundFetchCallback {
25 override fun shouldCancel(uri: FreenetURI, mimeType: String, size: Long): Boolean {
26 return !mimeType.startsWith("image/") || (size > 2097152)
29 override fun loaded(uri: FreenetURI, mimeType: String, data: ByteArray) {
30 if (!mimeType.startsWith("image/")) {
33 ByteArrayInputStream(data).use {
36 imageCache.get(uri.toString().decode().normalize()) { LinkedElement(uri.toString()) }
38 removeLoadingLink(uri)
41 override fun failed(uri: FreenetURI) {
42 failureCache.put(uri.toString().decode().normalize(), true)
43 removeLoadingLink(uri)
46 private fun removeLoadingLink(uri: FreenetURI) {
47 synchronized(loadingLinks) {
48 loadingLinks.invalidate(uri.toString().decode().normalize())
53 override fun loadElement(link: String): LinkedElement {
54 val normalizedLink = link.decode().normalize()
55 synchronized(loadingLinks) {
56 imageCache.getIfPresent(normalizedLink)?.run {
59 failureCache.getIfPresent(normalizedLink)?.run {
60 return LinkedElement(link, failed = true)
62 if (loadingLinks.getIfPresent(normalizedLink) == null) {
63 loadingLinks.put(normalizedLink, true)
64 freenetInterface.startFetch(FreenetURI(link), callback)
67 return LinkedElement(link, loading = true)
70 private fun String.decode() = URLDecoder.decode(this, "UTF-8")!!
71 private fun String.normalize() = Normalizer.normalize(this, Normalizer.Form.NFC)!!