Fix newline characters not rendering as line breaks

src/main/java/com/mitchej123/hodgepodge/config/FixesConfig.java

@@ -36,6 +36,14 @@ public class FixesConfig {
     @Config.DefaultBoolean(true)
     public static boolean fixChatWrappedColors;
 
+    @Config.Comment("Fix newline characters in chat messages not rendering as line breaks")
+    @Config.DefaultBoolean(true)
+    public static boolean fixChatNewlines;
+
+    @Config.Comment("Fix newline characters in drawString not rendering as line breaks")
+    @Config.DefaultBoolean(true)
+    public static boolean fixFontRendererNewlines;
+
     @Config.Comment("Prevents crash if server sends container with wrong itemStack size")
     @Config.DefaultBoolean(true)
     public static boolean fixContainerPutStacksInSlots;

src/main/java/com/mitchej123/hodgepodge/mixins/Mixins.java

@@ -608,6 +608,14 @@ public enum Mixins implements IMixins {
             .addClientMixins("minecraft.MixinGuiNewChat_FixColorWrapping")
             .setApplyIf(() -> FixesConfig.fixChatWrappedColors)
             .setPhase(Phase.EARLY)),
+    FIX_CHAT_NEWLINES(new MixinBuilder("Fix newline characters in chat messages not rendering as line breaks")
+            .addClientMixins("minecraft.MixinGuiNewChat_FixChatNewlines")
+            .setApplyIf(() -> FixesConfig.fixChatNewlines)
+            .setPhase(Phase.EARLY)),
+    FIX_FONT_RENDERER_NEWLINES(new MixinBuilder("Fix newline characters in drawString not rendering as line breaks")
+            .addClientMixins("minecraft.MixinFontRenderer_NewlineSupport")
+            .setApplyIf(() -> FixesConfig.fixFontRendererNewlines)
+            .setPhase(Phase.EARLY)),
     COMPACT_CHAT(new MixinBuilder()
             .addClientMixins("minecraft.MixinGuiNewChat_CompactChat")
             .setApplyIf(() -> TweaksConfig.compactChat)

src/main/java/com/mitchej123/hodgepodge/mixins/early/minecraft/MixinFontRenderer_NewlineSupport.java

@@ -0,0 +1,39 @@
+package com.mitchej123.hodgepodge.mixins.early.minecraft;
+
+import java.util.List;
+
+import net.minecraft.client.gui.FontRenderer;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+@Mixin(FontRenderer.class)
+public abstract class MixinFontRenderer_NewlineSupport {
+
+    @Shadow
+    public int FONT_HEIGHT;
+
+    @Shadow
+    public abstract List<String> listFormattedStringToWidth(String str, int wrapWidth);
+
+    @Shadow
+    private int renderString(String text, int x, int y, int color, boolean shadow) {
+        return 0;
+    }
+
+    @Inject(method = "renderString", at = @At("HEAD"), cancellable = true)
+    private void hodgepodge$handleNewlines(String text, int x, int y, int color, boolean shadow,
+            CallbackInfoReturnable<Integer> cir) {
+        if (text == null || text.indexOf('\n') < 0) return;
+
+        List<String> lines = this.listFormattedStringToWidth(text, Integer.MAX_VALUE);
+        int lastX = 0;
+        for (int i = 0; i < lines.size(); i++) {
+            lastX = this.renderString(lines.get(i), x, y + i * this.FONT_HEIGHT, color, shadow);
+        }
+        cir.setReturnValue(lastX);
+    }
+}

src/main/java/com/mitchej123/hodgepodge/mixins/early/minecraft/MixinGuiNewChat_FixChatNewlines.java

@@ -0,0 +1,46 @@
+package com.mitchej123.hodgepodge.mixins.early.minecraft;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import net.minecraft.client.gui.FontRenderer;
+import net.minecraft.client.gui.GuiNewChat;
+import net.minecraft.util.ChatComponentText;
+import net.minecraft.util.IChatComponent;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(GuiNewChat.class)
+public class MixinGuiNewChat_FixChatNewlines {
+
+    @Inject(method = "printChatMessageWithOptionalDeletion", at = @At("HEAD"), cancellable = true)
+    private void hodgepodge$splitNewlines(IChatComponent component, int id, CallbackInfo ci) {
+        String formatted = component.getFormattedText();
+        if (formatted.indexOf('\n') < 0) return;
+
+        List<IChatComponent> lines = hodgepodge$splitOnNewlines(formatted);
+        for (int i = 0; i < lines.size(); i++) {
+            ((GuiNewChat) (Object) this).printChatMessageWithOptionalDeletion(lines.get(i), i == 0 ? id : 0);
+        }
+        ci.cancel();
+    }
+
+    @Unique
+    private static List<IChatComponent> hodgepodge$splitOnNewlines(String formatted) {
+        String[] parts = formatted.split("\n", -1);
+        List<IChatComponent> lines = new ArrayList<>();
+        String carryFormat = "";
+
+        for (String part : parts) {
+            String fullLine = carryFormat + part;
+            lines.add(new ChatComponentText(fullLine));
+            carryFormat = FontRenderer.getFormatFromString(fullLine);
+        }
+
+        return lines;
+    }
+}