MapDownloader module

Author: emyfops

common/src/main/kotlin/com/lambda/module/modules/player/MapDownloader.kt

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2025 Lambda
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.lambda.module.modules.player
+
+import com.lambda.event.events.TickEvent
+import com.lambda.event.listener.SafeListener.Companion.listen
+import com.lambda.module.Module
+import com.lambda.module.tag.ModuleTag
+import com.lambda.util.FolderRegister
+import com.lambda.util.FolderRegister.locationBoundDirectory
+import com.lambda.util.StringUtils.hash
+import com.lambda.util.player.SlotUtils.combined
+import com.lambda.util.world.entitySearch
+import net.minecraft.block.MapColor
+import net.minecraft.entity.decoration.ItemFrameEntity
+import net.minecraft.item.FilledMapItem
+import net.minecraft.item.map.MapState
+import java.awt.image.BufferedImage
+import javax.imageio.ImageIO
+
+object MapDownloader : Module(
+    name = "MapDownloader",
+    description = "Save map data to your computer",
+    defaultTags = setOf(ModuleTag.PLAYER),
+) {
+    init {
+        listen<TickEvent.Pre> {
+            val mapStates = entitySearch<ItemFrameEntity>(128.0)
+                .mapNotNull { FilledMapItem.getMapState(it.heldItemStack, world) } +
+                    player.combined.mapNotNull { FilledMapItem.getMapState(it, world) }
+
+            mapStates.forEach { map ->
+                val name = map.hash
+                val image = map.toBufferedImage()
+
+                val file = FolderRegister.maps.toFile().locationBoundDirectory().resolve("$name.png")
+                if (file.exists()) return@listen
+
+                ImageIO.write(image, "png", file)
+            }
+        }
+    }
+
+    private val MapState.hash: String
+        get() = colors.hash("SHA-256")
+
+    fun MapState.toBufferedImage(): BufferedImage {
+        val image = BufferedImage(128, 128, BufferedImage.TYPE_INT_ARGB)
+
+        repeat(128) { x ->
+            repeat(128) { y ->
+                val index = colors[x + y * 128].toInt()
+                val color = MapColor.getRenderColor(index)
+
+                val b = (color shr 16) and 0xFF
+                val g = (color shr 8) and 0xFF
+                val r = (color shr 0) and 0xFF
+
+                val argb = -0x1000000 or (r shl 16) or (g shl 8) or (b shl 0)
+                image.setRGB(x, y, argb)
+            }
+        }
+
+        return image
+    }
+}

common/src/main/kotlin/com/lambda/util/FolderRegister.kt

@@ -48,9 +48,10 @@ object FolderRegister : Loadable {
     val replay: Path = lambda.resolve("replay")
     val cache: Path = lambda.resolve("cache")
     val structure: Path = lambda.resolve("structure")
+    val maps: Path = lambda.resolve("maps")
 
     override fun load(): String {
-        val folders = listOf(lambda, config, packetLogs, replay, cache, structure)
+        val folders = listOf(lambda, config, packetLogs, replay, cache, structure, maps)
         val createdFolders = folders.mapNotNull {
             if (it.notExists()) {
                 it.createDirectories()

common/src/main/kotlin/com/lambda/util/StringUtils.kt

@@ -17,6 +17,8 @@
 
 package com.lambda.util
 
+import java.security.MessageDigest
+
 object StringUtils {
     /**
      * Returns a sanitized file path for both Unix and Linux systems
@@ -89,4 +91,32 @@ object StringUtils {
 
         return cost[len0 - 1]
     }
+
+    /**
+     * See [MessageDigest section](https://docs.oracle.com/en/java/javase/11/docs/specs/security/standard-names.html#messagedigest-algorithms) of the Java Security Standard Algorithm Names Specification
+     *
+     * @receiver        The string to hash
+     * @param algorithm The algorithm instance to use
+     *
+     * @return          The string representation of the hash
+     */
+    fun String.hash(algorithm: String): String =
+        MessageDigest
+            .getInstance(algorithm)
+            .digest(toByteArray())
+            .joinToString(separator = "") { "%02x".format(it) }
+
+    /**
+     * See [MessageDigest section](https://docs.oracle.com/en/java/javase/11/docs/specs/security/standard-names.html#messagedigest-algorithms) of the Java Security Standard Algorithm Names Specification
+     *
+     * @receiver        The byte array to hash
+     * @param algorithm The algorithm instance to use
+     *
+     * @return          The string representation of the hash
+     */
+    fun ByteArray.hash(algorithm: String): String =
+        MessageDigest
+            .getInstance(algorithm)
+            .digest(this)
+            .joinToString(separator = "") { "%02x".format(it) }
 }