function handleInput(action, active) {
    if (isGameOver) { if(active) location.reload(); return; }

    const relativeTick = currentTick - lastSentTick;

    if (action === "JUMP" && active) {
        if (player.grounded && !isCrouching) {
            player.vy = JUMP_POWER;
            player.grounded = false;
            inputLog.push({ t: relativeTick, act: "JUMP" });
        }
    }
    if (action === "DUCK") { isCrouching = active; }
}

// Event Listeners
window.addEventListener('keydown', (e) => {
    if (e.target.tagName === 'INPUT' || e.target.tagName === 'TEXTAREA') return;

    if (e.code === 'Space' || e.code === 'ArrowUp') handleInput("JUMP", true);
    if (e.code === 'ArrowDown' || e.code === 'KeyS') handleInput("DUCK", true);
});
window.addEventListener('keyup', (e) => {
    if (e.target.tagName === 'INPUT' || e.target.tagName === 'TEXTAREA') return;

    if (e.code === 'ArrowDown' || e.code === 'KeyS') handleInput("DUCK", false);
});
window.addEventListener('mousedown', (e) => {
    if (e.target === canvas && e.button === 0) handleInput("JUMP", true);
});

// Touch Logic
let touchStartY = 0;
window.addEventListener('touchstart', (e) => {
    if(e.target === canvas) { e.preventDefault(); touchStartY = e.touches[0].clientY; }
}, { passive: false });
window.addEventListener('touchend', (e) => {
    if(e.target === canvas) {
        e.preventDefault();
        const diff = e.changedTouches[0].clientY - touchStartY;
        if (diff < -30) handleInput("JUMP", true);
        else if (diff > 30) { handleInput("DUCK", true); setTimeout(() => handleInput("DUCK", false), 800); }
        else if (Math.abs(diff) < 10) handleInput("JUMP", true);
    }
});