Caching URL Infos

app/src/main/java/com/vitorpamplona/amethyst/model/LocalCache.kt

@@ -2,6 +2,7 @@ package com.vitorpamplona.amethyst.model
 
 import android.util.Log
 import androidx.lifecycle.LiveData
+import com.baha.url.preview.UrlInfoItem
 import com.fasterxml.jackson.databind.DeserializationFeature
 import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
 import com.vitorpamplona.amethyst.service.model.ReactionEvent
@@ -103,6 +104,8 @@ object LocalCache {
       it.addReply(note)
     }
 
+    UrlCachedPreviewer.preloadPreviewsFor(note)
+
     refreshObservers()
   }
 

app/src/main/java/com/vitorpamplona/amethyst/model/UrlCachedPreviewer.kt

@@ -0,0 +1,55 @@
+package com.vitorpamplona.amethyst.model
+
+import com.baha.url.preview.BahaUrlPreview
+import com.baha.url.preview.IUrlPreviewCallback
+import com.baha.url.preview.UrlInfoItem
+import com.vitorpamplona.amethyst.ui.components.imageExtension
+import com.vitorpamplona.amethyst.ui.components.isValidURL
+import com.vitorpamplona.amethyst.ui.components.noProtocolUrlValidator
+import com.vitorpamplona.amethyst.ui.components.videoExtension
+import java.util.concurrent.ConcurrentHashMap
+
+object UrlCachedPreviewer {
+  val cache = ConcurrentHashMap<String, UrlInfoItem>()
+
+  fun previewInfo(url: String, callback: IUrlPreviewCallback? = null) {
+    cache[url]?.let {
+      callback?.onComplete(it)
+      return
+    }
+
+    BahaUrlPreview(url, object : IUrlPreviewCallback {
+      override fun onComplete(urlInfo: UrlInfoItem) {
+        cache.put(url, urlInfo)
+        callback?.onComplete(urlInfo)
+      }
+
+      override fun onFailed(throwable: Throwable) {
+        callback?.onFailed(throwable)
+      }
+    }).fetchUrlPreview()
+  }
+
+  fun findUrlsInMessage(message: String): List<String> {
+    return message.split('\n').map { paragraph ->
+      paragraph.split(' ').filter { word: String ->
+        isValidURL(word) || noProtocolUrlValidator.matcher(word).matches()
+      }
+    }.flatten()
+  }
+
+  fun preloadPreviewsFor(note: Note) {
+    note.event?.content?.let {
+      findUrlsInMessage(it).forEach {
+        val removedParamsFromUrl = it.split("?")[0].toLowerCase()
+        if (imageExtension.matcher(removedParamsFromUrl).matches()) {
+          // Preload Images? Isn't this too heavy?
+        } else if (videoExtension.matcher(removedParamsFromUrl).matches()) {
+          // Do nothing for now.
+        } else {
+          previewInfo(it)
+        }
+      }
+    }
+  }
+}

app/src/main/java/com/vitorpamplona/amethyst/ui/components/UrlPreview.kt

@@ -31,6 +31,7 @@ import coil.compose.AsyncImage
 import com.baha.url.preview.BahaUrlPreview
 import com.baha.url.preview.IUrlPreviewCallback
 import com.baha.url.preview.UrlInfoItem
+import com.vitorpamplona.amethyst.model.UrlCachedPreviewer
 
 
 @Composable
@@ -41,7 +42,7 @@ fun UrlPreview(url: String, urlText: String, showUrlIfError: Boolean = true) {
 
   // Doesn't use a viewModel because of viewModel reusing issues (too many UrlPreview are created).
   LaunchedEffect(url) {
-    BahaUrlPreview(url, object : IUrlPreviewCallback {
+    UrlCachedPreviewer.previewInfo(url, object : IUrlPreviewCallback {
       override fun onComplete(urlInfo: UrlInfoItem) {
         if (urlInfo.allFetchComplete() && urlInfo.url == url)
           urlPreviewState = UrlPreviewState.Loaded(urlInfo)
@@ -52,7 +53,7 @@ fun UrlPreview(url: String, urlText: String, showUrlIfError: Boolean = true) {
       override fun onFailed(throwable: Throwable) {
         urlPreviewState = UrlPreviewState.Error("Error parsing preview for ${url}: ${throwable.message}")
       }
-    }).fetchUrlPreview()
+    })
   }
 
   Crossfade(targetState = urlPreviewState) { state ->

app/src/main/java/com/vitorpamplona/amethyst/ui/components/VideoView.kt

@@ -40,7 +40,6 @@ fun VideoView(videoUri: String) {
     }
   }
 
-  println("CCC"+exoPlayer.videoFormat?.width)
   AndroidView(
     modifier = Modifier
       .fillMaxWidth(),