package com.mojang.blaze3d.platform;

import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import org.lwjgl.glfw.GLFW;

@Environment(EnvType.CLIENT)
public class TextInputManager {
	private final Window window;
	private boolean textInputEnabled;
	private boolean imeRequested;
	private volatile boolean imeStatusChanged = true;
	private boolean cachedIMEStatus;

	public TextInputManager(final Window window) {
		this.window = window;
	}

	public void setTextInputArea(final int x0, final int y0, final int x1, final int y1) {
		int guiScale = this.window.getGuiScale();
		GLFW.glfwSetPreeditCursorRectangle(this.window.handle(), x0 * guiScale, y0 * guiScale, (x1 - x0) * guiScale, (y1 - y0) * guiScale);
	}

	public void notifyIMEChanged() {
		this.imeStatusChanged = true;
	}

	public void tick() {
		if (this.textInputEnabled) {
			this.tickDuringTextInput();
		} else {
			this.tickOutsideTextInput();
		}
	}

	private boolean getIMEStatus() {
		if (this.imeStatusChanged) {
			this.imeStatusChanged = false;
			this.cachedIMEStatus = GLFW.glfwGetInputMode(this.window.handle(), 208903) == 1;
		}

		return this.cachedIMEStatus;
	}

	private void tickOutsideTextInput() {
		if (this.window.isFocused() && this.getIMEStatus()) {
			this.setIMEInputMode(false);
		}
	}

	private void tickDuringTextInput() {
		this.imeRequested = this.getIMEStatus();
	}

	public void startTextInput() {
		this.textInputEnabled = true;
		if (this.imeRequested) {
			this.setIMEInputMode(true);
		}
	}

	public void stopTextInput() {
		this.textInputEnabled = false;
	}

	public void onTextInputFocusChange(final boolean focused) {
		if (focused) {
			this.startTextInput();
		} else {
			this.stopTextInput();
		}
	}

	private void setIMEInputMode(final boolean value) {
		GLFW.glfwSetInputMode(this.window.handle(), 208903, GLX.glfwBool(value));
	}
}