From e619767b04ad57e4608f7bbf44325ce6391c597d Mon Sep 17 00:00:00 2001
From: MrLetsplay <mr@cringe-studios.com>
Date: Sun, 15 Oct 2023 19:46:28 +0200
Subject: [PATCH] Better TextField cursor

---
 src/kekengine/cpp/ui/uielements.cpp | 22 +++++++++++++++++++++-
 src/kekengine/cpp/util/utils.cpp    |  4 ++--
 src/kekengine/include/utils.h       | 18 ++++++++++++++++--
 3 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/src/kekengine/cpp/ui/uielements.cpp b/src/kekengine/cpp/ui/uielements.cpp
index 6d68dc8..4fb77bf 100644
--- a/src/kekengine/cpp/ui/uielements.cpp
+++ b/src/kekengine/cpp/ui/uielements.cpp
@@ -1,6 +1,7 @@
 #include "uielements.h"
 
 #include <GLFW/glfw3.h>
+#include <algorithm>
 #include <glm/gtc/type_ptr.hpp>
 #include <string>
 
@@ -239,8 +240,24 @@ void TextFieldElement::updateText(std::u32string newText) {
 	this->text = Unicode::convertU32ToStd(newText);
 	this->textElement->setText(this->text);
 
+	UIBounds bounds = getBounds();
 	TextMetrics m = textElement->text->getMetrics(0, newText.length() - cursorPos, textElement->sizePixels);
-	this->cursor->x = uiPx(m.width);
+	TextMetrics fullM = textElement->text->getMetrics(0, newText.length(), textElement->sizePixels);
+
+	// Set offset to keep cursor visible
+	float offsetX = -this->textElement->x.pixels;
+	float minOffsetX = std::max(m.width - bounds.w + 1, 0);
+	float maxOffsetX = m.width;
+
+	// Adjust offset to make sure the text field is always fully utilized (if possible)
+	float adjust = bounds.w - (fullM.width - offsetX);
+	std::cout << adjust << std::endl;
+	if(adjust > 0) offsetX -= adjust;
+
+	offsetX = clamp(offsetX, minOffsetX, maxOffsetX);
+
+	this->cursor->x = uiPx(m.width - offsetX);
+	this->textElement->x = uiPx(-offsetX);
 }
 
 UIElementType TextFieldElement::getType() {
@@ -310,6 +327,9 @@ void TextFieldElement::focusExit() {
 
 	Input::uncaptureKeyboardInput(capture);
 	capture = KEK_INVALID_ID;
+
+	cursorPos = 0;
+	updateText(Unicode::convertStdToU32(this->text));
 }
 
 void TextFieldElement::draw(UIPoint screenPos, glm::mat4 projection) {
diff --git a/src/kekengine/cpp/util/utils.cpp b/src/kekengine/cpp/util/utils.cpp
index f76103c..8b18312 100644
--- a/src/kekengine/cpp/util/utils.cpp
+++ b/src/kekengine/cpp/util/utils.cpp
@@ -16,13 +16,13 @@ float clamp(float value, float min, float max) {
 	return value;
 }
 
-float clampCyclic(int value, int min, int max) {
+int clampCyclic(int value, int min, int max) {
 	while(value > max) value -= (max - min);
 	while(value < min) value += (max - min);
 	return value;
 }
 
-float clamp(int value, int min, int max) {
+int clamp(int value, int min, int max) {
 	if(value > max) value = max;
 	if(value < min) value = min;
 	return value;
diff --git a/src/kekengine/include/utils.h b/src/kekengine/include/utils.h
index 1c88f2b..3b2859f 100644
--- a/src/kekengine/include/utils.h
+++ b/src/kekengine/include/utils.h
@@ -39,9 +39,23 @@ float clampCyclic(float value, float min, float max);
 
 float clamp(float value, float min, float max);
 
-float clampCyclic(int value, int min, int max);
+int clampCyclic(int value, int min, int max);
 
-float clamp(int value, int min, int max);
+int clamp(int value, int min, int max);
+
+template <typename T>
+T clamp(T value, T min, T max) {
+	if(value > max) value = max;
+	if(value < min) value = min;
+	return value;
+}
+
+template <typename T>
+T clampCyclic(T value, T min, T max) {
+	while(value > max) value -= (max - min);
+	while(value < min) value += (max - min);
+	return value;
+}
 
 enum class CubeFace {
 	FRONT,