1 files changed, 124 insertions, 0 deletions
diff --git a/src/main/kotlin/org/polyfrost/chatting/chat/ChatSpamBlock.kt b/src/main/kotlin/org/polyfrost/chatting/chat/ChatSpamBlock.kt
new file mode 100644
index 0000000..da5dde8
--- /dev/null
+++ b/src/main/kotlin/org/polyfrost/chatting/chat/ChatSpamBlock.kt
@@ -0,0 +1,124 @@
+package org.polyfrost.chatting.chat
+
+import org.polyfrost.chatting.config.ChattingConfig
+import com.google.gson.JsonObject
+import com.google.gson.JsonParser
+import java.text.Normalizer
+import net.minecraft.util.ChatComponentText
+import net.minecraft.util.EnumChatFormatting
+import net.minecraftforge.client.event.ClientChatReceivedEvent
+import net.minecraftforge.fml.common.eventhandler.SubscribeEvent
+
+object ChatSpamBlock {
+    /*
+    Made by @KTibow
+    Based off of Unspam (also by @KTibow)
+    Algorithm based off of https://paulgraham.com/spam.html
+    */
+    private val PLAYER_MESSAGE = Regex("^(\\[VIP\\+?\\] |\\[MVP\\+?\\+?\\] |)(\\w{2,16}): (.*)$")
+
+    @SubscribeEvent
+    fun onChat(event: ClientChatReceivedEvent) {
+        val message = event.message.unformattedText.replace(Regex("\u00A7."), "")
+        if (!PLAYER_MESSAGE.matches(message)) return
+
+        val (rank, player, content) = PLAYER_MESSAGE.matchEntire(message)!!.destructured
+
+        if (ChattingConfig.spamThreshold != 100) {
+            val tokens = tokenize(content)
+            val spamProb = findSpamProbability(tokens)
+            if (spamProb * 100 > ChattingConfig.spamThreshold) {
+                if (ChattingConfig.hideSpam) {
+                    event.isCanceled = true
+                } else {
+                    var newMessage =
+                        EnumChatFormatting.DARK_GRAY.toString() +
+                            EnumChatFormatting.STRIKETHROUGH.toString()
+                    if (!ChattingConfig.customChatFormatting) {
+                        newMessage += rank
+                    }
+                    newMessage += "$player${EnumChatFormatting.DARK_GRAY}: $content"
+                    event.message = ChatComponentText(newMessage)
+                }
+                return
+            }
+        }
+        if (ChattingConfig.customChatFormatting) {
+            val coloredPlayer = findRankColor(rank) + player + EnumChatFormatting.RESET.toString()
+            event.message = ChatComponentText("$coloredPlayer: $content")
+        }
+    }
+
+    private fun tokenize(message: String): MutableList<String> {
+        val strippedMessage =
+            Normalizer.normalize(message, Normalizer.Form.NFKC)
+                .replace(Regex("[^\\w\\s/]"), " ")
+                .lowercase()
+                .trim()
+        val tokens = strippedMessage.split(Regex("\\s+")).toMutableList()
+        if (tokens.size <= 2) {
+            tokens.add("TINY_LENGTH")
+        } else if (tokens.size <= 4) {
+            tokens.add("SMALL_LENGTH")
+        } else if (tokens.size <= 7) {
+            tokens.add("MEDIUM_LENGTH")
+        } else {
+            tokens.add("LONG_LENGTH")
+        }
+        if (message.replace(Regex("[\\w\\s]"), "").length > 2) {
+            tokens.add("SPECIAL_CHARS")
+        } else if (message.replace(Regex("[\\w\\s]"), "").isNotEmpty()) {
+            tokens.add("SPECIAL_CHAR")
+        } else {
+            tokens.add("LOW_SPECIAL_CHARS")
+        }
+        if (message.replace(Regex("[^A-Z]"), "").length >= message.length / 4) {
+            tokens.add("HIGH_CAPS")
+        } else {
+            tokens.add("LOW_CAPS")
+        }
+        return tokens
+    }
+
+    private fun findSpamProbability(tokens: MutableList<String>): Double {
+        val tokenProbs = mutableMapOf<String, Double>()
+        for (token in tokens) {
+            if (!spamInfoJson.has(token)) continue
+            val spamInToken = spamInfoJson.get(token).asJsonObject.get("spam").asDouble
+            val fineInToken = spamInfoJson.get(token).asJsonObject.get("fine").asDouble
+            tokenProbs[token] =
+                ((spamInToken / messageCountsJson.get("spam").asInt) /
+                    (fineInToken / messageCountsJson.get("fine").asInt +
+                        spamInToken / messageCountsJson.get("spam").asInt))
+        }
+        val spamProbs = tokenProbs.values.toMutableList()
+        val fineProbs = tokenProbs.values.map { 1 - it }.toMutableList()
+        val spamProbability = spamProbs.reduce { a, b -> a * b }
+        val fineProbability = fineProbs.reduce { a, b -> a * b }
+        return spamProbability / (spamProbability + fineProbability)
+    }
+
+    private fun findRankColor(rank: String): String {
+        println(rank)
+        return when (rank) {
+            "[VIP] ",
+            "[VIP+] " -> EnumChatFormatting.GREEN.toString()
+            "[MVP] ",
+            "[MVP+] " -> EnumChatFormatting.AQUA.toString()
+            "[MVP++] " -> EnumChatFormatting.GOLD.toString()
+            else -> EnumChatFormatting.GRAY.toString()
+        }
+    }
+
+    private fun getResourceAsText(path: String): String? =
+        object {}.javaClass.getResource(path)?.readText()
+    private val spamInfoJson: JsonObject
+    private val messageCountsJson: JsonObject
+
+    init {
+        // Load the file spamInfo.json from resources/
+        val spamInfo = getResourceAsText("/spamInfo.json")
+        spamInfoJson = JsonParser().parse(spamInfo).asJsonObject
+        messageCountsJson = JsonParser().parse(" { \"fine\": 668, \"spam\": 230 }").asJsonObject
+    }
+}