From 188ef3762d7c249a52abf1a1d9baa7c9fff797a0 Mon Sep 17 00:00:00 2001
From: Vitor Pamplona <vitor@vitorpamplona.com>
Date: Mon, 2 Oct 2023 17:31:34 -0400
Subject: [PATCH] Allows Base64 images on profiles.

---
 .../ui/components/RobohashAsyncImage.kt       | 105 +++++++++++++++---
 1 file changed, 92 insertions(+), 13 deletions(-)

diff --git a/app/src/main/java/com/vitorpamplona/amethyst/ui/components/RobohashAsyncImage.kt b/app/src/main/java/com/vitorpamplona/amethyst/ui/components/RobohashAsyncImage.kt
index 6da68fa4d..1e2a160d1 100644
--- a/app/src/main/java/com/vitorpamplona/amethyst/ui/components/RobohashAsyncImage.kt
+++ b/app/src/main/java/com/vitorpamplona/amethyst/ui/components/RobohashAsyncImage.kt
@@ -1,7 +1,13 @@
 package com.vitorpamplona.amethyst.ui.components
 
+import android.content.Context
+import android.graphics.BitmapFactory
+import android.net.Uri
 import androidx.compose.foundation.Image
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.Stable
+import androidx.compose.runtime.derivedStateOf
+import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
@@ -11,9 +17,19 @@ import androidx.compose.ui.graphics.FilterQuality
 import androidx.compose.ui.graphics.drawscope.DrawScope
 import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.platform.LocalContext
+import androidx.core.graphics.drawable.toDrawable
+import coil.ImageLoader
 import coil.compose.AsyncImage
 import coil.compose.AsyncImagePainter
 import coil.compose.rememberAsyncImagePainter
+import coil.decode.DataSource
+import coil.fetch.DrawableResult
+import coil.fetch.FetchResult
+import coil.fetch.Fetcher
+import coil.request.ImageRequest
+import coil.request.Options
+import com.vitorpamplona.amethyst.service.checkNotInMainThread
+import java.util.Base64
 
 @Composable
 fun RobohashAsyncImage(
@@ -67,19 +83,40 @@ fun RobohashFallbackAsyncImage(
     )
 
     if (model != null && loadProfilePicture) {
-        AsyncImage(
-            model = model,
-            contentDescription = contentDescription,
-            modifier = modifier,
-            placeholder = painter,
-            fallback = painter,
-            error = painter,
-            alignment = alignment,
-            contentScale = contentScale,
-            alpha = alpha,
-            colorFilter = colorFilter,
-            filterQuality = filterQuality
-        )
+        val isBase64 by remember {
+            derivedStateOf {
+                model.startsWith("data:image/jpeg;base64,")
+            }
+        }
+
+        if (isBase64) {
+            val painter = rememberAsyncImagePainter(
+                model = Base64Requester.imageRequest(context, model)
+            )
+
+            Image(
+                painter = painter,
+                contentDescription = null,
+                modifier = modifier,
+                alignment = alignment,
+                contentScale = contentScale,
+                colorFilter = colorFilter
+            )
+        } else {
+            AsyncImage(
+                model = model,
+                contentDescription = contentDescription,
+                modifier = modifier,
+                placeholder = painter,
+                fallback = painter,
+                error = painter,
+                alignment = alignment,
+                contentScale = contentScale,
+                alpha = alpha,
+                colorFilter = colorFilter,
+                filterQuality = filterQuality
+            )
+        }
     } else {
         Image(
             painter = painter,
@@ -118,3 +155,45 @@ fun RobohashAsyncImageProxy(
         loadProfilePicture = loadProfilePicture
     )
 }
+
+object Base64Requester {
+    fun imageRequest(context: Context, message: String): ImageRequest {
+        return ImageRequest
+            .Builder(context)
+            .data(message)
+            .fetcherFactory(Base64Fetcher.Factory)
+            .build()
+    }
+}
+
+@Stable
+class Base64Fetcher(
+    private val options: Options,
+    private val data: Uri
+) : Fetcher {
+
+    override suspend fun fetch(): FetchResult {
+        checkNotInMainThread()
+
+        val base64String = data.toString().removePrefix("data:image/jpeg;base64,")
+
+        val byteArray = Base64.getDecoder().decode(base64String)
+        val bitmap = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.size)
+
+        if (bitmap == null) {
+            throw Exception("Unable to load base64 $base64String")
+        }
+
+        return DrawableResult(
+            drawable = bitmap.toDrawable(options.context.resources),
+            isSampled = false,
+            dataSource = DataSource.MEMORY
+        )
+    }
+
+    object Factory : Fetcher.Factory<Uri> {
+        override fun create(data: Uri, options: Options, imageLoader: ImageLoader): Fetcher {
+            return Base64Fetcher(options, data)
+        }
+    }
+}