adds support for secret emojis

2025-11-10 11:57:29 +01:00 · 2025-03-05 13:40:51 -05:00
parent 0580aef4a2
commit 7e2724ea31
7 changed files with 275 additions and 9 deletions
--- a/commons/src/main/java/com/vitorpamplona/amethyst/commons/emojicoder/EmojiCoder.kt
+++ b/commons/src/main/java/com/vitorpamplona/amethyst/commons/emojicoder/EmojiCoder.kt
@@ -0,0 +1,109 @@
+/**
+ * Copyright (c) 2024 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.emojicoder
+
+object EmojiCoder {
+    // Variation selectors block https://unicode.org/charts/nameslist/n_FE00.html
+    // VS1..=VS16
+    const val VARIATION_SELECTOR_START = 0xfe00
+    const val VARIATION_SELECTOR_END = 0xfe0f
+
+    // Variation selectors supplement https://unicode.org/charts/nameslist/n_E0100.html
+    // VS17..=VS256
+    const val VARIATION_SELECTOR_SUPPLEMENT_START = 0xe0100
+    const val VARIATION_SELECTOR_SUPPLEMENT_END = 0xe01ef
+
+    val toVariationArray =
+        Array<CharArray>(256) {
+            // converts to UTF-16. Always char[2] back
+            when (it) {
+                in 0..15 -> Character.toChars(VARIATION_SELECTOR_START + it)
+                in 16..255 -> Character.toChars(VARIATION_SELECTOR_SUPPLEMENT_START + it - 16)
+                else -> throw RuntimeException("This should never happen")
+            }
+        }
+
+    fun fromVariationSelector(codePoint: Int): Int? =
+        when (codePoint) {
+            in VARIATION_SELECTOR_START..VARIATION_SELECTOR_END -> codePoint - VARIATION_SELECTOR_START
+            in VARIATION_SELECTOR_SUPPLEMENT_START..VARIATION_SELECTOR_SUPPLEMENT_END -> codePoint - VARIATION_SELECTOR_SUPPLEMENT_START + 16
+            else -> null
+        }
+
+    fun isVariationChar(charCode: Int) =
+        charCode in VARIATION_SELECTOR_START..VARIATION_SELECTOR_END ||
+            charCode in VARIATION_SELECTOR_SUPPLEMENT_START..VARIATION_SELECTOR_SUPPLEMENT_END
+
+    @JvmStatic
+    fun isCoded(text: String): Boolean {
+        if (text.length <= 3) return false
+
+        if (!isVariationChar(text.codePointAt(text.length - 2))) {
+            return false
+        }
+
+        if (text.length > 4 && !isVariationChar(text.codePointAt(text.length - 4))) {
+            return false
+        }
+
+        return true
+    }
+
+    @JvmStatic
+    fun encode(
+        emoji: String,
+        text: String,
+    ): String {
+        val input = text.toByteArray(Charsets.UTF_8)
+        val out = CharArray(input.size * 2)
+        var outIdx = 0
+        for (i in 0 until input.size) {
+            val chars = toVariationArray[input[i].toInt() and 0xFF]
+            out[outIdx++] = chars[0]
+            out[outIdx++] = chars[1]
+        }
+        return emoji + String(out)
+    }
+
+    @JvmStatic
+    fun decode(text: String): String {
+        val decoded = mutableListOf<Int>()
+
+        var i = 0
+        while (i < text.length) {
+            val codePoint = text.codePointAt(i)
+            val byte = fromVariationSelector(codePoint)
+
+            if (byte == null && decoded.isNotEmpty()) {
+                break
+            } else if (byte == null) {
+                i += Character.charCount(codePoint) // Advance index by correct number of chars
+                continue
+            }
+
+            decoded.add(byte)
+            i += Character.charCount(codePoint) // Advance index by correct number of chars
+        }
+
+        val decodedArray = ByteArray(decoded.size) { decoded[it].toByte() }
+        return String(decodedArray, Charsets.UTF_8)
+    }
+}
--- a/commons/src/main/java/com/vitorpamplona/amethyst/commons/richtext/RichTextParser.kt
+++ b/commons/src/main/java/com/vitorpamplona/amethyst/commons/richtext/RichTextParser.kt
@@ -24,6 +24,7 @@ import android.util.Log
 import android.util.Patterns
 import com.linkedin.urls.detection.UrlDetector
 import com.linkedin.urls.detection.UrlDetectorOptions
+import com.vitorpamplona.amethyst.commons.emojicoder.EmojiCoder
 import com.vitorpamplona.quartz.experimental.inlineMetadata.Nip54InlineMetadata
 import com.vitorpamplona.quartz.nip02FollowList.ImmutableListOfLists
 import com.vitorpamplona.quartz.nip30CustomEmoji.CustomEmoji
@@ -160,6 +161,7 @@ class RichTextParser {
            imagesForPagerWithBase64.values.toImmutableList(),
            emojiMap.toImmutableMap(),
            segments,
+            tags,
        )
    }

@@ -255,6 +257,8 @@ class RichTextParser {

        if (word.startsWith("#")) return parseHash(word, tags)

+        if (EmojiCoder.isCoded(word)) return SecretEmoji(word)
+
        if (word.contains("@")) {
            if (Patterns.EMAIL_ADDRESS.matcher(word).matches()) return EmailSegment(word)
        }
--- a/commons/src/main/java/com/vitorpamplona/amethyst/commons/richtext/RichTextParserSegments.kt
+++ b/commons/src/main/java/com/vitorpamplona/amethyst/commons/richtext/RichTextParserSegments.kt
@@ -21,17 +21,19 @@
 package com.vitorpamplona.amethyst.commons.richtext

 import androidx.compose.runtime.Immutable
+import com.vitorpamplona.quartz.nip02FollowList.ImmutableListOfLists
 import kotlinx.collections.immutable.ImmutableList
 import kotlinx.collections.immutable.ImmutableMap
 import kotlinx.collections.immutable.ImmutableSet

@Immutable
-data class RichTextViewerState(
+class RichTextViewerState(
    val urlSet: ImmutableSet<String>,
    val imagesForPager: ImmutableMap<String, MediaUrlContent>,
    val imageList: ImmutableList<MediaUrlContent>,
    val customEmoji: ImmutableMap<String, String>,
    val paragraphs: ImmutableList<ParagraphState>,
+    val tags: ImmutableListOfLists<String>,
 )

@Immutable
@@ -80,6 +82,10 @@ class EmailSegment(
    segment: String,
 ) : Segment(segment)

+class SecretEmoji(
+    segment: String,
+) : Segment(segment)
+
@Immutable
 class PhoneSegment(
    segment: String,
--- a/commons/src/test/java/com/vitorpamplona/amethyst/commons/emojicoder/EmojiCoderTest.kt
+++ b/commons/src/test/java/com/vitorpamplona/amethyst/commons/emojicoder/EmojiCoderTest.kt
@@ -0,0 +1,69 @@
+/**
+ * Copyright (c) 2024 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.emojicoder
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class EmojiCoderTest {
+    companion object {
+        val EMOJI_LIST = arrayOf("😀", "😂", "🥰", "😎", "🤔", "👍", "👎", "👏", "😅", "🤝", "🎉", "🎂", "🍕", "🌈", "🌞", "🌙", "🔥", "💯", "🚀", "👀", "💀", "🥹")
+
+        val testStrings =
+            arrayOf(
+                "Hello, World!",
+                "Testing 123",
+                "Special chars: !@#$%^&*()",
+                "Unicode: 你好，世界",
+                " ", // space only
+            )
+
+        val HELLO_WORLD = "\uD83D\uDE00\uDB40\uDD38\uDB40\uDD55\uDB40\uDD5C\uDB40\uDD5C\uDB40\uDD5F\uDB40\uDD1C\uDB40\uDD10\uDB40\uDD47\uDB40\uDD5F\uDB40\uDD62\uDB40\uDD5C\uDB40\uDD54\uDB40\uDD11"
+    }
+
+    @Test
+    fun testIsCoded() {
+        assertEquals(true, EmojiCoder.isCoded(HELLO_WORLD))
+    }
+
+    @Test
+    fun testEncode() {
+        assertEquals(HELLO_WORLD, EmojiCoder.encode("\uD83D\uDE00", "Hello, World!"))
+    }
+
+    @Test
+    fun testDecode() {
+        assertEquals("Hello, World!", EmojiCoder.decode(HELLO_WORLD))
+    }
+
+    @Test
+    fun testEncodeDecode() {
+        for (emoji in EMOJI_LIST) {
+            for (sentence in testStrings) {
+                val encoded = EmojiCoder.encode(emoji, sentence)
+                val decoded = EmojiCoder.decode(encoded)
+                assertEquals(sentence, decoded)
+                assertTrue("Failed sentence for emoji $emoji with sentence `$sentence`: `$encoded`", EmojiCoder.isCoded(encoded))
+            }
+        }
+    }
+}