Code/net/minecraft/client/gui/font/TextFieldHelper.java

package net.minecraft.client.gui.font;

import java.util.function.Consumer;
import java.util.function.Predicate;
import java.util.function.Supplier;
import net.minecraft.ChatFormatting;
import net.minecraft.Util;
import net.minecraft.client.Minecraft;
import net.minecraft.client.StringSplitter;
import net.minecraft.client.gui.screens.Screen;
import net.minecraft.util.Mth;
import net.minecraft.util.StringUtil;
import net.minecraftforge.api.distmarker.Dist;
import net.minecraftforge.api.distmarker.OnlyIn;

@OnlyIn(Dist.CLIENT)
public class TextFieldHelper {
    private final Supplier<String> getMessageFn;
    private final Consumer<String> setMessageFn;
    private final Supplier<String> getClipboardFn;
    private final Consumer<String> setClipboardFn;
    private final Predicate<String> stringValidator;
    private int cursorPos;
    private int selectionPos;

    public TextFieldHelper(
        Supplier<String> p_95137_, Consumer<String> p_95138_, Supplier<String> p_95139_, Consumer<String> p_95140_, Predicate<String> p_95141_
    ) {
        this.getMessageFn = p_95137_;
        this.setMessageFn = p_95138_;
        this.getClipboardFn = p_95139_;
        this.setClipboardFn = p_95140_;
        this.stringValidator = p_95141_;
        this.setCursorToEnd();
    }

    public static Supplier<String> createClipboardGetter(Minecraft p_95154_) {
        return () -> getClipboardContents(p_95154_);
    }

    public static String getClipboardContents(Minecraft p_95170_) {
        return ChatFormatting.stripFormatting(p_95170_.keyboardHandler.getClipboard().replaceAll("\\r", ""));
    }

    public static Consumer<String> createClipboardSetter(Minecraft p_95183_) {
        return p_95173_ -> setClipboardContents(p_95183_, p_95173_);
    }

    public static void setClipboardContents(Minecraft p_95156_, String p_95157_) {
        p_95156_.keyboardHandler.setClipboard(p_95157_);
    }

    public boolean charTyped(char p_95144_) {
        if (StringUtil.isAllowedChatCharacter(p_95144_)) {
            this.insertText(this.getMessageFn.get(), Character.toString(p_95144_));
        }

        return true;
    }

    public boolean keyPressed(int p_95146_) {
        if (Screen.isSelectAll(p_95146_)) {
            this.selectAll();
            return true;
        } else if (Screen.isCopy(p_95146_)) {
            this.copy();
            return true;
        } else if (Screen.isPaste(p_95146_)) {
            this.paste();
            return true;
        } else if (Screen.isCut(p_95146_)) {
            this.cut();
            return true;
        } else {
            TextFieldHelper.CursorStep textfieldhelper$cursorstep = Screen.hasControlDown() ? TextFieldHelper.CursorStep.WORD : TextFieldHelper.CursorStep.CHARACTER;
            if (p_95146_ == 259) {
                this.removeFromCursor(-1, textfieldhelper$cursorstep);
                return true;
            } else {
                if (p_95146_ == 261) {
                    this.removeFromCursor(1, textfieldhelper$cursorstep);
                } else {
                    if (p_95146_ == 263) {
                        this.moveBy(-1, Screen.hasShiftDown(), textfieldhelper$cursorstep);
                        return true;
                    }

                    if (p_95146_ == 262) {
                        this.moveBy(1, Screen.hasShiftDown(), textfieldhelper$cursorstep);
                        return true;
                    }

                    if (p_95146_ == 268) {
                        this.setCursorToStart(Screen.hasShiftDown());
                        return true;
                    }

                    if (p_95146_ == 269) {
                        this.setCursorToEnd(Screen.hasShiftDown());
                        return true;
                    }
                }

                return false;
            }
        }
    }

    private int clampToMsgLength(int p_95196_) {
        return Mth.clamp(p_95196_, 0, this.getMessageFn.get().length());
    }

    private void insertText(String p_95161_, String p_95162_) {
        if (this.selectionPos != this.cursorPos) {
            p_95161_ = this.deleteSelection(p_95161_);
        }

        this.cursorPos = Mth.clamp(this.cursorPos, 0, p_95161_.length());
        String s = new StringBuilder(p_95161_).insert(this.cursorPos, p_95162_).toString();
        if (this.stringValidator.test(s)) {
            this.setMessageFn.accept(s);
            this.selectionPos = this.cursorPos = Math.min(s.length(), this.cursorPos + p_95162_.length());
        }
    }

    public void insertText(String p_95159_) {
        this.insertText(this.getMessageFn.get(), p_95159_);
    }

    private void resetSelectionIfNeeded(boolean p_95164_) {
        if (!p_95164_) {
            this.selectionPos = this.cursorPos;
        }
    }

    public void moveBy(int p_232576_, boolean p_232577_, TextFieldHelper.CursorStep p_232578_) {
        switch (p_232578_) {
            case CHARACTER:
                this.moveByChars(p_232576_, p_232577_);
                break;
            case WORD:
                this.moveByWords(p_232576_, p_232577_);
        }
    }

    public void moveByChars(int p_169094_) {
        this.moveByChars(p_169094_, false);
    }

    public void moveByChars(int p_95151_, boolean p_95152_) {
        this.cursorPos = Util.offsetByCodepoints(this.getMessageFn.get(), this.cursorPos, p_95151_);
        this.resetSelectionIfNeeded(p_95152_);
    }

    public void moveByWords(int p_169096_) {
        this.moveByWords(p_169096_, false);
    }

    public void moveByWords(int p_95167_, boolean p_95168_) {
        this.cursorPos = StringSplitter.getWordPosition(this.getMessageFn.get(), p_95167_, this.cursorPos, true);
        this.resetSelectionIfNeeded(p_95168_);
    }

    public void removeFromCursor(int p_232573_, TextFieldHelper.CursorStep p_232574_) {
        switch (p_232574_) {
            case CHARACTER:
                this.removeCharsFromCursor(p_232573_);
                break;
            case WORD:
                this.removeWordsFromCursor(p_232573_);
        }
    }

    public void removeWordsFromCursor(int p_232580_) {
        int i = StringSplitter.getWordPosition(this.getMessageFn.get(), p_232580_, this.cursorPos, true);
        this.removeCharsFromCursor(i - this.cursorPos);
    }

    public void removeCharsFromCursor(int p_95190_) {
        String s = this.getMessageFn.get();
        if (!s.isEmpty()) {
            String s1;
            if (this.selectionPos != this.cursorPos) {
                s1 = this.deleteSelection(s);
            } else {
                int i = Util.offsetByCodepoints(s, this.cursorPos, p_95190_);
                int j = Math.min(i, this.cursorPos);
                int k = Math.max(i, this.cursorPos);
                s1 = new StringBuilder(s).delete(j, k).toString();
                if (p_95190_ < 0) {
                    this.selectionPos = this.cursorPos = j;
                }
            }

            this.setMessageFn.accept(s1);
        }
    }

    public void cut() {
        String s = this.getMessageFn.get();
        this.setClipboardFn.accept(this.getSelected(s));
        this.setMessageFn.accept(this.deleteSelection(s));
    }

    public void paste() {
        this.insertText(this.getMessageFn.get(), this.getClipboardFn.get());
        this.selectionPos = this.cursorPos;
    }

    public void copy() {
        this.setClipboardFn.accept(this.getSelected(this.getMessageFn.get()));
    }

    public void selectAll() {
        this.selectionPos = 0;
        this.cursorPos = this.getMessageFn.get().length();
    }

    private String getSelected(String p_95175_) {
        int i = Math.min(this.cursorPos, this.selectionPos);
        int j = Math.max(this.cursorPos, this.selectionPos);
        return p_95175_.substring(i, j);
    }

    private String deleteSelection(String p_95185_) {
        if (this.selectionPos == this.cursorPos) {
            return p_95185_;
        } else {
            int i = Math.min(this.cursorPos, this.selectionPos);
            int j = Math.max(this.cursorPos, this.selectionPos);
            String s = p_95185_.substring(0, i) + p_95185_.substring(j);
            this.selectionPos = this.cursorPos = i;
            return s;
        }
    }

    public void setCursorToStart() {
        this.setCursorToStart(false);
    }

    public void setCursorToStart(boolean p_95177_) {
        this.cursorPos = 0;
        this.resetSelectionIfNeeded(p_95177_);
    }

    public void setCursorToEnd() {
        this.setCursorToEnd(false);
    }

    public void setCursorToEnd(boolean p_95187_) {
        this.cursorPos = this.getMessageFn.get().length();
        this.resetSelectionIfNeeded(p_95187_);
    }

    public int getCursorPos() {
        return this.cursorPos;
    }

    public void setCursorPos(int p_169099_) {
        this.setCursorPos(p_169099_, true);
    }

    public void setCursorPos(int p_95180_, boolean p_95181_) {
        this.cursorPos = this.clampToMsgLength(p_95180_);
        this.resetSelectionIfNeeded(p_95181_);
    }

    public int getSelectionPos() {
        return this.selectionPos;
    }

    public void setSelectionPos(int p_169101_) {
        this.selectionPos = this.clampToMsgLength(p_169101_);
    }

    public void setSelectionRange(int p_95148_, int p_95149_) {
        int i = this.getMessageFn.get().length();
        this.cursorPos = Mth.clamp(p_95148_, 0, i);
        this.selectionPos = Mth.clamp(p_95149_, 0, i);
    }

    public boolean isSelecting() {
        return this.cursorPos != this.selectionPos;
    }

    @OnlyIn(Dist.CLIENT)
    public static enum CursorStep {
        CHARACTER,
        WORD;
    }
}